Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Military Readiness Activities in the Atlantic Fleet Training and Testing Study Area, 19858-20077 [2025-07780]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 90, Number 89 (Friday, May 9, 2025)]
[Proposed Rules]
[Pages 19858-20077]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-07780]



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Vol. 90

Friday,

No. 89

May 9, 2025

Part III





Department of Commerce





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National Oceanic and Atmospheric Administration





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50 CFR Part 218





Takes of Marine Mammals Incidental to Specified Activities; Taking 
Marine Mammals Incidental to Military Readiness Activities in the 
Atlantic Fleet Training and Testing Study Area; Proposed Rule

Federal Register / Vol. 90, No. 89 / Friday, May 9, 2025 / Proposed 
Rules

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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 218

[Docket No. 250430-0074]
RIN 0648-BN17


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Military Readiness Activities in 
the Atlantic Fleet Training and Testing Study Area

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Proposed rule; proposed letters of authorization; request for 
comments.

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SUMMARY: NMFS has received a request from the U.S. Department of the 
Navy (including the U.S. Navy and the U.S. Marine Corps (Navy)) and on 
behalf of the U.S. Coast Guard (Coast Guard; hereafter, Navy and Coast 
Guard are collectively referred to as Action Proponents) for Incidental 
Take Regulations (ITR) and three associated Letters of Authorization 
(LOAs) pursuant to the Marine Mammal Protection Act (MMPA). The 
requested regulations would govern the authorization of take of marine 
mammals incidental to training and testing activities conducted in the 
Atlantic Fleet Training and Testing (AFTT) Study Area over the course 
of seven years from November 2025 through November 2032. NMFS requests 
comments on this proposed rule. NMFS will consider public comments 
prior to making any final decision on the promulgation of the requested 
ITR and issuance of the LOAs; agency responses to public comments will 
be summarized in the final rule, if issued. The Action Proponents' 
activities are considered military readiness activities pursuant to the 
MMPA, as amended by the National Defense Authorization Act for Fiscal 
Year 2004 (2004 NDAA).

DATES: Comments and information must be received no later than June 9, 
2025.

ADDRESSES: A plain language summary of this proposed rule is available 
at https://www.regulations.gov/docket/NOAA-NMFS-2024-0115. You may 
submit comments on this document, identified by NOAA-NMFS-2024-0115, by 
any of the following methods:
     Electronic Submission: Submit all electronic public 
comments via the Federal e-Rulemaking Portal. Visit https://www.regulations.gov and type NOAA-NMFS-2024-0115 in the Search box. 
Click on the ``Comment'' icon, complete the required fields, and enter 
or attach your comments.
     Mail: Submit written comments to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service, 1315 East-West Highway, Silver 
Spring, MD 20910-3225.
     Fax: (301) 713-0376; Attn: Jolie Harrison.
    Instructions: Comments sent by any other method, to any other 
address or individual, or received after the end of the comment period, 
may not be considered by NMFS. All comments received are a part of the 
public record and will generally be posted for public viewing on 
https://www.regulations.gov without change. All personal identifying 
information (e.g., name, address, etc.), confidential business 
information, or otherwise sensitive information submitted voluntarily 
by the sender will be publicly accessible. NMFS will accept anonymous 
comments (enter ``N/A'' in the required fields if you wish to remain 
anonymous). Attachments to electronic comments will be accepted in 
Microsoft Word, Excel, or Adobe PDF file formats only.
    A copy of the Action Proponents' Incidental Take Authorization 
(ITA) application and supporting documents, as well as a list of the 
references cited in this document, may be obtained online at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities. In case of problems 
accessing these documents, please call the contact listed below (see 
FOR FURTHER INFORMATION CONTACT).

FOR FURTHER INFORMATION CONTACT: Alyssa Clevenstine, Office of 
Protected Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Purpose and Need for Regulatory Action

    This proposed rule, if promulgated, would provide a framework under 
the authority of the MMPA (16 U.S.C. 1361 et seq.) to allow for the 
authorization of take of marine mammals incidental to the Action 
Proponents' training and testing activities (which qualify as military 
readiness activities) involving the use of active sonar and other 
transducers, air guns, and explosives (also referred to as ``in-water 
detonations''); pile driving and vibratory extraction; and vessel 
movement in the AFTT Study Area. The AFTT Study Area includes air and 
water space of the western Atlantic Ocean along the east coast of North 
America, the Gulf of America (formerly Gulf of Mexico), and portions of 
the Caribbean Sea, covering approximately 2.6 million square nautical 
miles (nmi\2\; 8.9 million square kilometers (km\2\)) of ocean area 
(see figure 1.1-1 of the rulemaking and LOA application (hereafter 
referred to as the application)). Please see the Legal Authority for 
the Proposed Action section for relevant definitions.

Legal Authority for the Proposed Action

    The MMPA prohibits the ``take'' of marine mammals, with certain 
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to 
allow, upon request, the incidental, but not intentional, taking of 
small numbers of marine mammals by U.S. citizens who engage in a 
specified activity (other than commercial fishing) within a specified 
geographical region if certain findings are made and either regulations 
are proposed or, if the taking is limited to harassment, a notice of a 
proposed authorization is provided to the public for review and the 
opportunity to submit comment.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s) and will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for taking for subsistence uses 
(where relevant). Further, NMFS must prescribe the permissible methods 
of taking; other ``means of effecting the least practicable adverse 
impact'' on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of the species or stocks for 
taking for certain subsistence uses (referred to in shorthand as 
``mitigation''); and requirements pertaining to the monitoring and 
reporting of the takings. The MMPA defines ``take'' to mean to harass, 
hunt, capture, or kill, or attempt to harass, hunt, capture, or kill 
any marine mammal. The Preliminary Analysis and Negligible Impact 
Determination section discusses the definition of ``negligible 
impact.''
    The 2004 NDAA (Pub. L. 108-136) amended section 101(a)(5) of the 
MMPA to remove the ``small numbers'' and ``specified geographical 
region'' provisions and amended the definition of ``harassment'' as 
applied to a ``military readiness activity'' to read as follows 
(section 3(18)(B) of the MMPA): (i) Any act that injures or has the 
significant potential to injure a marine mammal or marine mammal stock 
in the

[[Page 19859]]

wild (Level A Harassment); or (ii) Any act that disturbs or is likely 
to disturb a marine mammal or marine mammal stock in the wild by 
causing disruption of natural behavioral patterns, including, but not 
limited to, migration, surfacing, nursing, breeding, feeding, or 
sheltering, to a point where such behavioral patterns are abandoned or 
significantly altered (Level B Harassment). The 2004 NDAA also amended 
the MMPA establishing that ``[f]or military readiness activity . . . , 
a determination of `least practicable adverse impact' . . . shall 
include consideration of personnel safety, practicality of 
implementation, and impact on the effectiveness of the military 
readiness activity.'' On August 13, 2018, the NDAA for Fiscal Year 2019 
(2019 NDAA) (Pub. L. 115-232) amended the MMPA to allow incidental take 
regulations for military readiness activities to be issued for up to 7 
years.

Summary of Major Provisions Within the Proposed Rule

    The major provisions of this proposed rule are:
    (i) The proposed take of marine mammals by Level A harassment and/
or Level B harassment;
    (ii) The proposed take of marine mammals by mortality or serious 
injury (M/SI);
    (iii) The proposed use of defined powerdown and shutdown zones 
(based on activity);
    (iv) Proposed measures to reduce the likelihood of vessel strikes;
    (v) Proposed activity limitations in certain areas and times that 
are biologically important (i.e., for foraging, migration, 
reproduction) for marine mammals;
    (vi) The proposed implementation of a Notification and Reporting 
Plan (for dead, live stranded, or marine mammals struck by any vessel 
engaged in military readiness activities); and
    (vii) The proposed implementation of a robust monitoring plan to 
improve our understanding of the environmental effects resulting from 
the Action Proponents' training and testing activities.
    This proposed rule includes an adaptive management component that 
allows for timely modification of mitigation, monitoring, and/or 
reporting measures based on new information, when appropriate.

Summary of Request

    On May 28, 2024, NMFS received an application from the Action 
Proponents requesting authorization to take marine mammals, by Level A 
and Level B harassment, incidental to training and testing 
(characterized as military readiness activities) including the use of 
sonar and other transducers, in-water detonations, air guns, and impact 
and vibratory pile driving and extraction conducted within the AFTT 
Study Area. In addition, the Action Proponents are requesting 
authorization to take, by serious injury or mortality, a limited number 
of several marine mammal species from explosives during training 
exercises, ship shock trials, and vessel movement during military 
readiness activities conducted within the AFTT Study Area over the 7-
year period of the LOAs. In response to our comments and following 
information exchange, the Action Proponents submitted a final revised 
application on August 16, 2024, that we determined was adequate and 
complete on August 19, 2024. On October 8, 2024, the Action Proponents 
submitted an updated application to revise take estimates on a subset 
of Navy activities. On September 20, 2024, we published a notice of 
receipt (NOR) of application in the Federal Register (89 FR 77106), 
requesting comments and information related to the Action Proponents' 
request for 30 days. During the 30-day public comment period on the 
NOR, we did not receive any public comments. On January 21, 2025, the 
Action Proponents submitted an updated application that removed ship 
shock trials and estimated take associated with that activity in Key 
West and within the Virginia Capes (VACAPES) Range Complex and, on 
February 13, 2025, the Action Proponents submitted an updated 
application containing minor revisions.
    NMFS has previously promulgated incidental take regulations 
pursuant to the MMPA relating to similar military readiness activities 
in AFTT. NMFS published the first rule effective from January 22, 2009 
through January 22, 2014 (74 FR 4844, January 27, 2009), the second 
rule effective from November 14, 2013 through November 13, 2018 (78 FR 
73009, December 4, 2013), and the third rule effective from November 
14, 2018 through November 13, 2023 (83 FR 57076, November 14, 2018), 
which was subsequently amended, extending the effective date until 
November 13, 2025 (84 FR 70712, December 23, 2019) pursuant to the 2019 
NDAA. For this proposed rulemaking, the Action Proponents propose to 
conduct substantially similar training and testing activities within 
the AFTT Study Area that were conducted under previous rules.
    The Action Proponents' application reflects the most up-to-date 
compilation of training and testing activities deemed necessary to 
accomplish military readiness requirements. The types and numbers of 
activities included in the proposed rule account for fluctuations in 
training and testing to meet evolving or emergent military readiness 
requirements. These proposed regulations would cover military readiness 
activities in the AFTT Study Area that would occur for a 7-year period 
following the expiration of the existing MMPA authorization on November 
13, 2025.

Description of Proposed Activity

Overview

    The Action Proponents request authorization to take marine mammals 
incidental to conducting military readiness activities. The Action 
Proponents have determined that acoustic and explosives stressors are 
most likely to result in take of marine mammals that could rise to the 
level of harassment, and take by serious injury or mortality may result 
from vessel movement, explosive use, and ship shock trials. Detailed 
descriptions of these activities are provided in chapter 2 of the 2024 
AFTT Draft Supplemental Environmental Impact Statement (EIS)/Overseas 
EIS (OEIS) (2024 AFTT Draft Supplemental EIS/OEIS) (https://www.nepa.navy.mil/aftteis/) and in the Action Proponents' application 
(https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities) and are 
summarized here.
    The Navy's statutory mission is to organize, train, equip, and 
maintain combat-ready naval forces for the peacetime promotion of the 
national security interests and prosperity of the United States, and 
for prompt and sustained combat incident to operations essential to the 
prosecution of a naval campaign. These missions are mandated by Federal 
law (10 U.S.C. 8062 and 10 U.S.C. 8063), which requires the readiness 
of the naval forces of the United States. The Navy executes this 
responsibility by establishing and executing at-sea training and 
testing, often in designated operating areas (OPAREA) and testing and 
training ranges. The Navy must be able to access and utilize these 
areas and associated sea and air space to develop and maintain skills 
for conducting naval operations. The Navy's testing activities ensure 
naval forces are equipped with well-maintained systems that take 
advantage of the latest technological advances. The Navy's research and 
acquisition community conducts military readiness activities that 
involve testing. The Navy tests vessels, aircraft, weapons, combat 
systems, sensors, and

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related equipment, and conducts scientific research activities to 
achieve and maintain military readiness.
    The mission of the Coast Guard is to ensure the maritime safety, 
security, and stewardship of the United States. To advance this 
mission, the Coast Guard must ensure its personnel can qualify and 
train jointly with, and independently of, the Navy and other services 
in the effective and safe operational use of Coast Guard vessels, 
aircraft, and weapons under realistic conditions. These activities help 
ensure the Coast Guard can safely assist in the defense of the United 
States by protecting the United States' maritime safety, security, and 
natural resources in accordance with its national defense mission (14 
U.S.C. 102). Coast Guard training activities are described in more 
detail in appendix C of the 2024 AFTT Draft Supplemental EIS/OEIS and 
in the Action Proponents' application, and are summarized below.

Dates and Duration

    The specified activities would occur at any time during the 7-year 
period of validity of the regulations. The proposed number of military 
readiness activities are described in the Detailed Description of the 
Specified Activity section (table 4 through table 9).

Specified Geographical Region

    The AFTT Study Area includes areas of the western Atlantic Ocean 
along the east coast of North America, the Gulf of America, and 
portions of the Caribbean Sea, covering approximately 2.6 million 
nmi\2\ (8.9 million km\2\) of ocean area, oriented from the mean high 
tide line along the U.S. coast and extending east to 45-degree west 
longitude line, north to 65-degree north latitude line, and south to 
approximately the 20-degree north latitude line (figure 1). It also 
includes Navy and Coast Guard pierside locations and port transit 
channels, bays, harbors, inshore waterways (e.g., channels, rivers), 
and civilian ports where military readiness activities occur as well as 
vessel and aircraft transit routes between homeports and OPAREAs. New 
to the Study Area are inshore waters adjacent to the Gulf of America 
and changes to ship shock trial areas. The VACAPES and Key West ship 
shock trial areas were removed from the Study Area, the Gulf of America 
ship shock trial area was moved south, and the Jacksonville ship shock 
trial area expanded. The vast majority of military readiness activities 
occur within appropriately designated range complexes and testing 
ranges that fall within the confines of the Study Area. Please refer to 
figure 1.1-1 of the application for a color map of the AFTT Study Area 
and figure 2.1-1 through figure 2.1-5 for additional maps of the range 
complexes and testing ranges. A summary of the AFTT Range Complexes and 
Testing Ranges are provided in table 1, Inshore Areas are provided in 
table 2, and Ports and Piers are provided in table 3.
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                              Table 1--AFTT Study Area Training and Testing Ranges
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                 Name                       Basic location       Sea and undersea space         Air space
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Northeast Range Complexes............  750 miles along the      46,000 nmi\2\ of sea     29,000 nmi\2\ of
                                        coast from Maine to      and undersea space.      special use airspace.
                                        New Jersey.              Includes three
                                                                 OPAREAs: Boston,
                                                                 Narragansett Bay, and
                                                                 Atlantic City.
Naval Undersea Warfare Center          Includes the waters of   11,000 nmi\2\ of sea     Minimal testing occurs
 Division, Newport Testing Range.       Narragansett Bay,        and undersea space.      in airspace within the
                                        Rhode Island Sound,      Includes three           test area.
                                        Block Island Sound,      Restricted Areas:
                                        Buzzards Bay, Vineyard   Coddington Cove,
                                        Sound, and Long Island   Narragansett Bay, and
                                        Sound.                   Rhode Island Sound.
Virginia Capes Range Complex (VACAPES  250 miles along the      30,000 nmi\2\ of sea     30,000 nmi\2\ of
 RC).                                   coast from Delaware to   and undersea space.      special use airspace.
                                        North Carolina, from     Includes one OPAREA:
                                        the shoreline to 150     Virginia Capes.
                                        nmi seaward.
Navy Cherry Point Range Complex......  Off the coast of North   19,000 nmi\2\ of sea     19,000 nmi\2\ of
                                        and South Carolina,      and undersea space.      special use airspace.
                                        from the shoreline to    Includes one OPAREA:
                                        120 nmi seaward.         Navy Cherry Point.
Jacksonville Range Complex (JAX RC)..  520 miles along the      50,000 nmi\2\ of sea     64,000 nmi\2\ of
                                        coast from North         and undersea space.      special use airspace.
                                        Carolina to Florida,     Includes three
                                        from the shoreline to    OPAREAs: Charleston,
                                        roughly 250 nmi          Jacksonville and Cape
                                        seaward.                 Canaveral. Includes
                                                                 the Undersea Warfare
                                                                 Training Range.
Naval Surface Warfare Center,          Located adjacent to the  500 nmi\2\ of sea and    No associated special
 Carderock Division, South Florida      Port Everglades          undersea space.          use airspace.
 Ocean Measurement Facility Testing     entrance channel in
 Range (SFOMF).                         Fort Lauderdale,
                                        Florida; out to
                                        roughly 25 nmi from
                                        shore.
Key West Range Complex...............  Off the southwestern     8,000 nmi\2\ of sea and  23,000 nmi\2\ of
                                        coast of mainland        undersea space south     special use airspace.
                                        Florida and along the    of Key West. Includes
                                        southern Florida Keys,   one OPAREA: Key West.
                                        extending into the
                                        Gulf of America and
                                        the Straits of Florida.
Naval Surface Warfare Center, Panama   Off the panhandle of     23,000 nmi\2\ of sea     23,000 nmi\2\ of
 City Division Testing Area.            Florida and Alabama,     and undersea space.      special use airspace.
                                        extending from the       Includes two OPAREAs:
                                        shoreline 120 nmi        Panama City and
                                        seaward and includes     Pensacola.
                                        St. Andrew Bay.
Gulf Range Complex (Gulf RC).........  Includes geographically  20,000 nmi\2\ of sea     43,000 nmi\2\ of
                                        separated areas          and undersea space.      special use airspace.
                                        throughout the Gulf of   Includes four OPAREAs:
                                        America.                 Panama City,
                                                                 Pensacola, New
                                                                 Orleans, and Corpus
                                                                 Christi.
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Note: nmi = nautical mile, nmi\2\ = square nautical mile, areas and distances of locations, sea and undersea
  space, and airspace are approximations.


               Table 2--AFTT Study Area Inshore Locations
------------------------------------------------------------------------
             Name                      Associated inshore waters
------------------------------------------------------------------------
Northeast Range Complexes      Thames River, Narragansett Bay, Rhode
 Inshore.                       Island Sound, Block Island Sound.
Virginia Capes Range Complex   Lower Chesapeake Bay, James River and
 (VACAPES RC) Inshore.          tributaries, Broad Bay, York River.
Jacksonville Range Complex     Blount Island, Southeast Kings Bay,
 (JAX RC) Inshore.              Cooper River, St. Johns River, Port
                                Canaveral.
Key West Range Complex         Truman Harbor, Demolition Key.
 Inshore.
Gulf Range Complex (Gulf RC)   St. Andrew Bay, Atchafalaya Bay,
 Inshore.                       Atchafalaya River, Lake Borgne,
                                Pascagoula River, Mobile Bay.
------------------------------------------------------------------------
Note: The Gulf Range Complex Inshore includes geographically separated
  areas throughout the Gulf of America.


                Table 3--AFTT Study Area Ports and Piers
------------------------------------------------------------------------
                                                         Coast Guard
     Pierside locations          Civilian ports           locations
------------------------------------------------------------------------
Portsmouth Naval Shipyard    Bath, ME                Southwest Harbor,
                                                      ME
Naval Submarine Base New     Boston, MA              Boston, MA
 London
Naval Station Newport        Earle, NJ               Cape Cod, MA
Naval Station Norfolk        Delaware Bay, DE        New London, CT *
Joint Expeditionary Base     Hampton Roads, VA       New Haven CT *
 Little Creek Fort Story
Norfolk Naval Shipyard       Morehead City, NC       Newport, RI *
Naval Submarine Base Kings   Wilmington, NC          Montauk, NY
 Bay
Naval Station Mayport        Kings Bay, GA           Staten Island, NY *
Port Canaveral               Savannah, GA            Atlantic City, NJ
                             Mayport, FL             Chesapeake, VA
                             Port Canaveral, FL      Virginia Beach, VA
                                                      *
                             Tampa, FL               Portsmouth, VA*
                             Pascagoula, MS          Elizabeth City, NC
                             Gulfport, MS            Charleston, SC *
                             Beaumont, TX            Mayport, FL *
                             Corpus Christi, TX      Cape Canaveral, FL
                                                      *
                                                     Fort Pierce, FL *
                                                     Dania, FL *
                                                     Miami, FL *
                                                     Key West, FL *
                                                     St. Petersburg, FL
                                                      *
                                                     Pensacola, FL *
                                                     Opa Locka, FL
                                                     New Orleans, LA
                                                     Houston, TX
                                                     Corpus Christi, TX
------------------------------------------------------------------------
Note: CT: Connecticut; FL: Florida; GA: Georgia; LA: Louisiana; MA:
  Massachusetts; ME: Maine; MS: Mississippi; NC: North Carolina; NJ: New
  Jersey; NY: New York; RI: Rhode Island; SC: South Carolina; TX: Texas;
  VA: Virginia.

[[Page 19863]]

 
* Indicates Coast Guard cutter stations.

Detailed Description of the Specified Activity

    The Action Proponents propose to conduct military readiness 
activities within the AFTT Study Area and have been conducting military 
readiness activities in the Study Area for well over a century and with 
active sonar for over 70 years. The tempo and types of military 
readiness activities have fluctuated due to the introduction of new 
technologies, the evolving nature of international events, advances in 
warfighting doctrine and procedures, and changes in force structure 
(organization of vessels, weapons, and personnel). Such developments 
influenced the frequency, duration, intensity, and location of required 
military readiness activities.
Primary Mission Areas
    The Navy categorizes their activities into functional warfare areas 
called primary mission areas, while the Coast Guard categorizes their 
activities as operational mission programs. For the Navy, these 
activities generally fall into the following five primary mission areas 
(Coast Guard mission areas are discussed below). The Navy mission areas 
with activities that may result in incidental take of marine mammals 
(and stressors associated with training and testing activities within 
those mission areas) include the following:
    (i) Amphibious warfare (in-water detonations);
    (ii) Anti-submarine warfare (sonar and other transducers, in-water 
detonations);
    (iii) Expeditionary warfare (in-water detonations, pile driving and 
extraction);
    (iv) Mine warfare (sonar and other transducers, in-water 
detonations);
    (v) Surface warfare (in-water detonations); and
    (vi) Other (sonar and other transducers, air guns, vessel 
movement).
    Most Navy activities conducted in AFTT are categorized under one of 
these primary mission areas; activities that do not fall within one of 
these areas are listed as ``other activities.'' In addition, ship shock 
(in-water detonations) trials, a specific Navy testing activity related 
to vessel evaluation, would be conducted. The testing community also 
categorizes most, but not all, of its testing activities under these 
primary mission areas. The testing community has three additional 
categories of activities: vessel evaluation (inclusive of ship shock 
trials), unmanned systems (i.e., unmanned surface vehicles (USVs), 
unmanned underwater vehicles (UUVs)), and acoustic and oceanographic 
science and technology.
    The Action Proponents describe and analyze the effects of their 
activities within the application (see the 2024 AFTT Draft Supplemental 
EIS/OEIS for additional details). In their assessment, the Action 
Proponents concluded that sonar and other transducers, underwater 
detonations, air guns, and pile driving/extraction were the stressors 
most likely to result in impacts on marine mammals that could rise to 
the level of harassment (and serious injury or mortality by explosives 
or by vessel movement) as defined under the MMPA. Therefore, the Action 
Proponents' application provides their assessment of potential effects 
from these stressors in terms of the primary warfare mission areas in 
which they would be conducted.
    The Coast Guard has four major national defense missions:
    (i) Maritime intercept operations;
    (ii) Deployed port operations/security and defense;
    (iii) Peacetime engagement; and
    (iv) Environmental defense operations (which includes oil and 
hazardous substance response).
    The Coast Guard manages 6 major operational mission programs with 
11 statutory missions, which includes defense readiness. As part of the 
Coast Guard's defense mission, Title 14 U.S.C. 1 states the Coast Guard 
is ``at all times an armed force of the United States.'' As part of the 
Joint Forces, the Coast Guard maintains its readiness to carry out 
military operations in support of the policies and objectives of the 
U.S. government. As an armed force, the Coast Guard trains and operates 
in the joint military arena at any time and functions as a specialized 
service under the Navy in time of war or when directed by the 
President. Coast Guard service members are trained to respond 
immediately to support military operations and national security. 
Federal law created the framework for the relationship between the Navy 
and the Coast Guard (10 U.S.C. 101; 14 U.S.C. 2(7); 22 U.S.C.; 50 
U.S.C.). To meet these statutory requirements and effectively carry out 
these missions, the Coast Guard's air and surface units train using 
realistic scenarios, including training with the Navy in their primary 
mission areas. Every Coast Guard unit is trained to support all 
statutory missions and, thus, trained to meet all mission requirements, 
which includes their defense mission requirements. Since all Coast 
Guard's missions entail the deployment of cutters or boats and either 
fixed-wing or rotary aircraft, the Coast Guard training requirements 
for one mission generally overlaps with the training requirements of 
other missions. Thus, when the Coast Guard is training for its defense 
mission, the same skill sets are utilized for its other statutory 
missions.
    The Coast Guard's defense mission does not involve low- or mid-
frequency active sonar (LFAS or MFAS), missiles, in-water detonations, 
pile driving and extraction, or air guns that would result in 
harassment of marine mammals. For additional information on all 
activities in the Coast Guard's mission programs see appendix C of the 
2024 AFTT Draft Supplemental EIS/OEIS.
    Below, we provide additional detail for each of the applicable 
primary mission areas.
Amphibious Warfare--
    The mission of amphibious warfare is to project military power from 
the sea to the shore (i.e., attack a threat on land by a military force 
embarked on ships) through the use of naval firepower and expeditionary 
landing forces. Amphibious warfare operations include Navy and Marine 
Corps small unit reconnaissance or raid missions to large-scale 
amphibious exercises involving multiple ships and aircraft combined 
into a strike group.
    Amphibious warfare training ranges from individual, crew, and small 
unit events to large task force exercises. Individual and crew training 
include amphibious vehicles and naval gunfire support training. Such 
training includes shore assaults, boat raids, airfield or port 
seizures, reconnaissance, and disaster relief. Large-scale amphibious 
exercises involve ship-to-shore maneuvers, naval fire support such as 
shore bombardment, air strikes, and attacks on targets that are near 
friendly forces.
    Testing of guns, munitions, aircraft, ships, and amphibious vessels 
and vehicles used in amphibious warfare are often integrated into 
training activities and, in most cases, the systems are used in the 
same manner in which they are used for training activities. Amphibious 
warfare tests, when integrated with training activities or conducted 
separately as full operational evaluations on existing amphibious 
vessels and vehicles following maintenance, repair, or modernization, 
may be conducted independently or in conjunction with other amphibious 
ship and aircraft activities. Testing is performed to ensure effective 
ship-to-

[[Page 19864]]

shore coordination and transport of personnel, equipment, and supplies. 
Tests may also be conducted periodically on other systems, vessels, and 
aircraft intended for amphibious operations to assess operability and 
to investigate efficacy of new technologies.
Anti-Submarine Warfare--
    The mission of anti-submarine warfare is to locate, neutralize, and 
defeat hostile submarine forces that threaten Navy forces. Anti-
submarine warfare is based on the principle that surveillance and 
attack aircraft, ships, and submarines all search for hostile 
submarines. These forces operate together or independently to gain 
early warning and detection and to localize, track, target, and attack 
submarine threats.
    Anti-submarine warfare training addresses basic skills such as 
detecting and classifying submarines, as well as evaluating sounds to 
distinguish between enemy submarines and friendly submarines, ships, 
and marine life. More advanced training integrates the full spectrum of 
anti-submarine warfare from detecting and tracking a submarine to 
attacking a target using either exercise torpedoes (i.e., torpedoes 
that do not contain a warhead) or simulated weapons. These integrated 
anti-submarine warfare training exercises are conducted in coordinated, 
at-sea training events involving submarines, ships, and aircraft.
    Testing of anti-submarine warfare systems is conducted to develop 
new technologies and assess weapon performance and operability with new 
systems and platforms, such as unmanned systems. Testing uses ships, 
submarines, and aircraft to demonstrate capabilities of torpedoes, 
missiles, countermeasure systems, and underwater surveillance and 
communications systems. Tests may be conducted as part of a large-scale 
fleet training event involving submarines, ships, fixed-wing aircraft, 
and helicopters. These integrated training events offer opportunities 
to conduct research and acquisition activities and to train aircrew in 
the use of new or newly enhanced systems during a large-scale, complex 
exercise.
Expeditionary Warfare--
    The mission of expeditionary warfare is to provide security and 
surveillance in the littoral (at the shoreline), riparian (along a 
river), or coastal environments. Expeditionary warfare is wide ranging 
and includes defense of harbors, operation of remotely operated 
vehicles, defense against swimmers, and boarding/seizure operations.
    Expeditionary warfare training activities include Navy, Marine 
Corps, and Coast Guard underwater construction team training, dive and 
salvage operations, and insertion/extraction via air, surface, and 
subsurface platforms.
Mine Warfare--
    The mission of mine warfare is to detect, classify, and avoid or 
neutralize (disable) mines to protect U.S. ships and submarines, and to 
maintain free access to ports and shipping lanes. Mine warfare training 
for the Navy and Coast Guard falls into two primary categories: mine 
detection and classification, and mine countermeasure and 
neutralization. Mine warfare also includes offensive mine laying to 
gain control of or deny the enemy access to sea space. Naval mines can 
be laid by ships, submarines, UUVs, or aircraft.
    Mine warfare neutralization training includes exercises in which 
aircraft, ships, submarines, underwater vehicles, unmanned vehicles, or 
marine mammal detection systems search for mine shapes. Personnel train 
to destroy or disable mines by attaching underwater explosives to or 
near the mine or using remotely operated vehicles to destroy the mine.
    Mine warfare testing is similar to training but focuses on the 
development of mine warfare systems to improve sonar, laser, and 
magnetic detectors intended to hunt, locate, and record the positions 
of mines for avoidance or subsequent neutralization. Mine detection and 
classification testing involves the use of air, surface, and subsurface 
platforms using a variety of systems to locate and identify objects 
underwater. Mine countermeasure and neutralization testing includes the 
use of air, surface, and subsurface platforms to evaluate the 
effectiveness of tracking devices, countermeasure and neutralization 
systems, and explosive munitions to neutralize mine threats. Most 
neutralization tests use mine shapes, or non-explosive practice mines, 
to evaluate a new or enhanced capability; however, a small percentage 
require the use of high-explosive mines to evaluate and confirm 
effectiveness of various systems.
Surface Warfare--
    The mission of surface warfare is to obtain control of sea space 
from which naval forces may operate and entails offensive action 
against other surface and subsurface targets while also defending 
against enemy forces. In surface warfare, aircraft use cannons, air-to-
surface missiles, and other precision-guided munitions; ships employ 
torpedoes, naval guns, and surface-to-surface missiles; and submarines 
attack surface ships using torpedoes.
    Surface warfare training includes Navy and Coast Guard surface-to-
surface gunnery and missile exercises, air-to-surface gunnery, bombing, 
and missile exercises, submarine torpedo launch events, other munitions 
against surface targets, and amphibious operations in a contested 
environment.
    Testing of weapons used in surface warfare is conducted to develop 
new technologies and to assess weapon performance and operability with 
new systems and platforms, such as unmanned systems. Tests include 
various air-to-surface guns and missiles, surface-to-surface guns and 
missiles, and bombing tests. Testing events may be integrated into 
training activities to test aircraft or aircraft systems in the 
delivery of ordnance on a surface target. In most cases the tested 
systems are used in the same manner in which they are used for training 
activities.
Overview of Training Activities Within the Study Area
    The Action Proponents routinely train in the AFTT Study Area in 
preparation for national defense missions. Training activities and 
exercises covered in this proposed rule are briefly described below and 
in more detail within appendix A (Activity Descriptions) of the 2024 
AFTT Draft Supplemental EIS/OEIS. The description, annual number of 
activities, and location of each training activity are provided by 
stressor category in table 4, table 5, and table 6. Each training 
activity described meets a requirement that can be traced ultimately to 
requirements set forth by the National Command Authority.
    Within the Navy, a major training exercise (MTE) is comprised of 
multiple ``unit-level'' exercises conducted by several units operating 
together while commanded and controlled by a single commander (these 
units are collectively referred to as carrier and expeditionary strike 
groups). These exercises typically employ an exercise scenario 
developed to train and evaluate the strike group in tactical naval 
tasks. In a MTE, most of the operations and activities being directed 
and coordinated by the strike group commander are identical in nature 
to the operations conducted during individual, crew, and smaller unit-
level training events. However, in MTEs, these disparate training tasks 
are conducted in concert rather than in isolation. Some integrated or 
coordinated anti-submarine warfare exercises are similar in that they 
are composed of several unit-level exercises

[[Page 19865]]

but are generally on a smaller scale than a MTE, are shorter in 
duration, use fewer assets, and use fewer hours of hull-mounted sonar 
per exercise. Coordinated training exercises involve multiple units 
working together to meet unit-level training requirements, whereas 
integrated training exercises involve multiple units working together 
for deployment. Coordinated exercises involving the use of sonar are 
presented under the category of anti-submarine warfare. The anti-
submarine warfare portions of these exercises are considered together 
in coordinated activities for the sake of acoustic modeling. When other 
training objectives are being met, those activities are described via 
unit-level training in each of the relevant primary mission areas.
    With a smaller fleet of approximately 250 cutters, Coast Guard 
activities are not as extensive as Navy activities due to differing 
mission requirements. However, the Coast Guard does train with the Navy 
and conducts some of the same training as the Navy. The Coast Guard 
does not conduct any exercises similar in scale to Navy MTEs/integrated 
exercises, and the use of mid- or low-frequency sonar, missiles, and 
underwater detonations are examples of actions that are not a part of 
the Coast Guard's mission requirements. Coast Guard training generally 
occurs close to the vessel homeport or close to shore, on established 
Navy testing and training ranges, or in transit to a scheduled patrol/
mission. There are approximately 1,600 Coast Guard vessels (cutters up 
to 418 feet (ft; 127.4 meters (m)) and boats less than 65 ft (19.8 m)), 
and the largest cutters would be underway for 3 to 4 months, whereas 
the smaller cutters would be underway from a few days to 4 weeks. The 
busiest regions for the Coast Guard are the Gulf of America due to the 
number of busy commercial ports, and Hampton Roads due to many of the 
cutters being based at facilities in that area.
    The MTEs and integrated/coordinated training activities analyzed 
for this request are Navy-led exercises in which the Coast Guard may 
participate and described in table 4. For additional information on 
these activities, see table 1.3-1 of the application and appendix A 
(Activity Descriptions) of the 2024 AFTT Draft Supplemental EIS/OEIS. 
Table 5 describes the proposed Navy training activities analyzed within 
the AFTT Study Area while table 6 describes the proposed Coast Guard 
training activities analyzed within the AFTT Study Area. In addition to 
participating in Navy-led exercises, Coast Guard training activities 
include unit-level activities conducted independently of, and not in 
coordination with, the Navy.

                  Table 4--Major Training Exercises and Integrated/Coordinated Training Activities Analyzed Within the AFTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                         Typical  hull-
        Training type           Exercise group      Description         Scale           Duration     Location (range      Exercise       mounted  sonar
                                                                                                         complex)         examples         per event
--------------------------------------------------------------------------------------------------------------------------------------------------------
Major Training Exercise......  Large Integrated  Larger-scale,     Greater than 6   Generally        Jacksonville     COMPTUEX.......  <500 hours.
                                ASW.              longer duration   surface ASW      greater than     Range Complex,
                                                  integrated ASW    units (up to     10 days.         Navy Cherry
                                                  exercises.        30 with the                       Point Range
                                                                    largest                           Complex,
                                                                    exercises), 2                     Virginia Capes
                                                                    or more                           Range Complex.
                                                                    submarines,
                                                                    multiple ASW
                                                                    aircraft.
Major Training Exercise......  Medium            Medium-scale,     Approximately 3- Generally 4-10   Jacksonville     Sustainment/     100-300 hours.
                                Integrated ASW.   medium duration   8 surface ASW    days.            Range Complex,   Task Force
                                                  integrated ASW    units, at                         Navy Cherry      Exercise.
                                                  exercises.        least 1                           Point Range
                                                                    submarine,                        Complex,
                                                                    multiple ASW                      Virginia Capes
                                                                    aircraft.                         Range Complex.
Integrated/Coordinated         Small Integrated  Small-scale,      Approximately 3- Generally less   Jacksonville     SWATT, NUWTAC..  50-100 hours.
 Training.                      ASW.              short duration    6 surface ASW    than 5 days.     Range Complex,
                                                  integrated ASW    units, 2                          Navy Cherry
                                                  exercises.        dedicated                         Point Range
                                                                    submarines, 2-                    Complex,
                                                                    6 ASW aircraft.                   Virginia Capes
                                                                                                      Range Complex.
Integrated/Coordinated         Medium            Medium-scale,     Approximately 2- Generally 3-10   Jacksonville     ASW Tactical     <100 hours.
 Training.                      Coordinated ASW.  medium            4 surface ASW    days.            Range Complex,   Development
                                                  duration,         units,                            Navy Cherry      Exercise.
                                                  coordinated ASW   possibly a                        Point Range
                                                  exercises.        submarine, 2-5                    Complex,
                                                                    ASW aircraft.                     Virginia Capes
                                                                                                      Range Complex.
Integrated/Coordinated         Small             Small-scale,      Approximately 2- Generally 2-4    Jacksonville     ARG/MEU          <50 hours.
 Training.                      Coordinated ASW.  short duration,   4 surface ASW    days.            Range Complex,   COMPTUEX.
                                                  coordinated ASW   units,                            Navy Cherry
                                                  exercises.        possibly a                        Point Range
                                                                    submarine, 1-2                    Complex,
                                                                    ASW aircraft.                     Virginia Capes
                                                                                                      Range Complex.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: ASW: anti-submarine warfare; COMPTUEX: Composite Training Unit Exercise; SWATT: Surface Warfare Advanced Tactical Training Exercise; NUWTAC: Navy
  Undersea Warfare Training Assessment Course; ARG/MEU: Amphibious Ready Group/Marine Expeditionary Unit.


[[Page 19866]]


                                                         Table 5--Proposed Navy Training Activities Analyzed Within the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                   Number of    Number of
     Stressor category          Activity type          Activity name                        Description                          Source bin        activities   activities        Location
                                                                                                                                                     1-year       7-year
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic..................  Major Training         Composite Training     Aircraft carrier and carrier air wing integrate  LFH, MFM, MFH, MF1,            2-3           17  Jacksonville Range
                             Exercise--Large        Unit Exercise.         with surface and submarine and Coast Guard       MF1C, Broadband (MF                              Complex, Navy
                             Integrated ASW.                               units in a challenging multi-threat              to HF).                                          Cherry Point Range
                                                                           operational environment that certifies them                                                       Complex, Virginia
                                                                           ready to deploy.                                                                                  Capes Range
                                                                                                                                                                             Complex.
Acoustic..................  Major Training         Sustainment/Task       Aircraft carrier and carrier air wing            LFH, MFM, MFH, MF1,              2           14  Jacksonville Range
                             Exercise--Medium       Force Exercise.        integrates with surface and submarine units in   MF1C, Broadband (MF                              Complex, Navy
                             Integrated ASW.                               a challenging multi-threat operational           to HF).                                          Cherry Point Range
                                                                           environment to maintain ability to deploy.                                                        Complex, Virginia
                                                                                                                                                                             Capes Range
                                                                                                                                                                             Complex.
Acoustic..................  Small Integrated ASW   Navy Undersea Warfare  Multiple ships, aircraft, and submarines         LFH, MFM, MFH, MF1,              2           14  Jacksonville Range
                             Training.              Training Assessment    integrate the use of their sensors, including    MF1C, Broadband (MF                              Complex, Navy
                                                    Course.                sonobuoys, to search for, detect, classify,      to HF).                                          Cherry Point Range
                                                                           localize, and track a threat submarine.                                                           Complex, Virginia
                                                                                                                                                                             Capes Range
                                                                                                                                                                             Complex.
Acoustic..................  Small Integrated ASW   Surface Warfare        Multiple ships and aircraft coordinate the use   LFH, MFM, MFH, MF1,              2           14  Jacksonville Range
                             Training.              Advanced Tactical      of sensors, including sonobuoys, to search,      MF1C, Broadband (MF                              Complex, Navy
                                                    Training.              detect, and track a threat submarine. Surface    to HF).                                          Cherry Point Range
                                                                           Warfare Advanced Tactical Training (SWATT)                                                        Complex, Virginia
                                                                           exercises are not dedicated anti-submarine                                                        Capes Range
                                                                           warfare exercises and involve multiple warfare                                                    Complex.
                                                                           areas.
Acoustic..................  Medium Coordinated     Tactical Development   Multiple ships, aircraft, and submarines         MFM, MFH, MF1, MF1C,             1            7  Jacksonville Range
                             ASW Training.          Exercise.              coordinate their efforts to search for,          Broadband (MF to HF).                            Complex.
                                                                           detect, and track submarines with the use of
                                                                           all sensors. Anti-Submarine Warfare Tactical
                                                                           Development Exercise is a dedicated anti-
                                                                           submarine warfare exercise.
Acoustic..................  Medium Coordinated     Tactical Development   Multiple ships, aircraft, and submarines         MFM, MFH, MF1, MF1C,             1            7  Virginia Capes Range
                             ASW Training.          Exercise.              coordinate their efforts to search for,          Broadband (MF to HF).                            Complex.
                                                                           detect, and track submarines with the use of
                                                                           all sensors. Anti-Submarine Warfare Tactical
                                                                           Development Exercise is a dedicated anti-
                                                                           submarine warfare exercise.
Acoustic..................  Small Coordinated ASW  Group Sail...........  Surface ships, Coast Guard Cutters, and          MFM, MFH, MF1, MF1C,             5           35  Jacksonville Range
                             Training.                                     helicopters integrate to search for, detect,     Broadband (MF to HF).                            Complex.
                                                                           and track threat submarines. Group Sails are
                                                                           not dedicated anti-submarine warfare exercises
                                                                           and involve multiple warfare areas.
Acoustic..................  Small Coordinated ASW  Group Sail...........  Surface ships, Coast Guard Cutters, and          MFM, MFH, MF1, MF1C,             4           28  Navy Cherry Point
                             Training.                                     helicopters integrate to search for, detect,     Broadband (MF to HF).                            Range Complex.
                                                                           and track threat submarines. Group Sails are
                                                                           not dedicated anti-submarine warfare exercises
                                                                           and involve multiple warfare areas.
Acoustic..................  Small Coordinated ASW  Group Sail...........  Surface ships, Coast Guard Cutters, and          MFM, MFH, MF1, MF1C,             5           35  Virginia Capes Range
                             Training.                                     helicopters integrate to search for, detect,     Broadband (MF to HF).                            Complex.
                                                                           and track threat submarines. Group Sails are
                                                                           not dedicated anti-submarine warfare exercises
                                                                           and involve multiple warfare areas.
Acoustic..................  Small Coordinated ASW  Amphibious Ready       Amphibious Ready Group exercises are conducted   LFH, MFM, MFH, MF1,              1            7  Navy Cherry Point
                             Training.              Group Marine           to validate the Marine Expeditionary Unit's      Broadband (MF to HF).                            Range Complex.
                                                    Expeditionary Unit     readiness for deployment and include small
                                                    Composite Training     boat raids; visit, board, search, and seizure
                                                    Unit Exercise.         training; helicopter and mechanized amphibious
                                                                           raids; and non-combatant evacuation
                                                                           operations.
Explosive.................  Amphibious Warfare...  Amphibious Operations  Navy and Marine Corps forces conduct operations  E1, E2, E3, E6, E9,             45          315  Navy Cherry Point
                                                    in a Contested         in coastal and offshore waterways against air,   E10.                                             Range Complex.
                                                    Environment.           surface, and subsurface threats.

[[Page 19867]]

 
Explosive.................  Amphibious Warfare...  Amphibious Operations  Navy and Marine Corps forces conduct operations  E1, E2, E3, E6, E9,             12           84  Virginia Capes Range
                                                    in a Contested         in coastal and offshore waterways against air,   E10.                                             Complex.
                                                    Environment.           surface, and subsurface threats.
Acoustic..................  Anti-Submarine         Anti-Submarine         Helicopter crews search for, track, and detect   MFM, MFH, HFH,                  14           98  Jacksonville Range
                             Warfare.               Warfare Torpedo        submarines. Recoverable air launched torpedoes   Broadband (MF to HF).                            Complex.
                                                    Exercise--Helicopter.  are employed against submarine targets.
Acoustic..................  Anti-Submarine         Anti-Submarine         Helicopter crews search for, track, and detect   MFM, MFH, HFH,                   4           28  Virginia Capes Range
                             Warfare.               Warfare Torpedo        submarines. Recoverable air launched torpedoes   Broadband (MF to HF).                            Complex.
                                                    Exercise--Helicopter.  are employed against submarine targets.
Acoustic..................  Anti-Submarine         Anti-Submarine         Maritime patrol aircraft crews search for,       MFM, HFH, Broadband             14           98  Jacksonville Range
                             Warfare.               Warfare Torpedo        track, and detect submarines. Recoverable air    (MF to HF).                                      Complex.
                                                    Exercise--Maritime     launched torpedoes are employed against
                                                    Patrol Aircraft.       submarine targets.
Acoustic..................  Anti-Submarine         Anti-Submarine         Maritime patrol aircraft crews search for,       MFM, HFH, Broadband              4           28  Virginia Capes Range
                             Warfare.               Warfare Torpedo        track, and detect submarines. Recoverable air    (MF to HF).                                      Complex.
                                                    Exercise--Maritime     launched torpedoes are employed against
                                                    Patrol Aircraft.       submarine targets.
Acoustic..................  Anti-Submarine         Anti-Submarine         Surface ship crews search for, track, and        MF1, HFH, Broadband             16          112  Jacksonville Range
                             Warfare.               Warfare Torpedo        detect submarines. Exercise torpedoes are used   (MF to HF).                                      Complex.
                                                    Exercise--Ship.        during this exercise.
Acoustic..................  Anti-Submarine         Anti-Submarine         Surface ship crews search for, track, and        MF1, HFH, Broadband              5           35  Virginia Capes Range
                             Warfare.               Warfare Torpedo        detect submarines. Exercise torpedoes are used   (MF to HF).                                      Complex.
                                                    Exercise--Ship.        during this exercise.
Acoustic..................  Anti-Submarine         Anti-Submarine         Submarine crews search for, track, and detect    HFH, Broadband (MF to           12           84  Jacksonville Range
                             Warfare.               Warfare Torpedo        submarines. Exercise torpedoes are used during   HF).                                             Complex.
                                                    Exercise--Submarine.   this exercise.
Acoustic..................  Anti-Submarine         Anti-Submarine         Submarine crews search for, track, and detect    HFH, Broadband (MF to            6           42  Northeast Range
                             Warfare.               Warfare Torpedo        submarines. Exercise torpedoes are used during   HF).                                             Complexes.
                                                    Exercise--Submarine.   this exercise.
Acoustic..................  Anti-Submarine         Anti-Submarine         Submarine crews search for, track, and detect    HFH, Broadband (MF to            2           14  Virginia Capes Range
                             Warfare.               Warfare Torpedo        submarines. Exercise torpedoes are used during   HF).                                             Complex.
                                                    Exercise--Submarine.   this exercise.
Acoustic..................  Anti-Submarine         Anti-Submarine         Helicopter crews search for, track, and detect   MFM, MFH.............            3           21  Gulf Range Complex.
                             Warfare.               Warfare Tracking       submarines.
                                                    Exercise--Helicopter.
Acoustic..................  Anti-Submarine         Anti-Submarine         Helicopter crews search for, track, and detect   MFM, MFH.............          370        2,590  Jacksonville Range
                             Warfare.               Warfare Tracking       submarines.                                                                                       Complex.
                                                    Exercise--Helicopter.
Acoustic..................  Anti-Submarine         Anti-Submarine         Helicopter crews search for, track, and detect   MFM, MFH.............           12           84  Navy Cherry Point
                             Warfare.               Warfare Tracking       submarines.                                                                                       Range Complex.
                                                    Exercise--Helicopter.
Acoustic..................  Anti-Submarine         Anti-Submarine         Helicopter crews search for, track, and detect   MFM, MFH.............           24          168  Other AFTT Areas.
                             Warfare.               Warfare Tracking       submarines.
                                                    Exercise--Helicopter.
Acoustic..................  Anti-Submarine         Anti-Submarine         Helicopter crews search for, track, and detect   MFM, MFH.............            8           56  Virginia Capes Range
                             Warfare.               Warfare Tracking       submarines.                                                                                       Complex.
                                                    Exercise--Helicopter.
Acoustic..................  Anti-Submarine         Anti-Submarine         Maritime patrol aircraft crews search for,       LFM, LFH, MFM........          475        3,325  Jacksonville Range
                             Warfare.               Warfare Tracking       track, and detect submarines.                                                                     Complex.
                                                    Exercise--Maritime
                                                    Patrol Aircraft.
Acoustic..................  Anti-Submarine         Anti-Submarine         Maritime patrol aircraft crews search for,       LFM, LFH, MFM........           35          245  Navy Cherry Point
                             Warfare.               Warfare Tracking       track, and detect submarines.                                                                     Range Complex.
                                                    Exercise--Maritime
                                                    Patrol Aircraft.
Acoustic..................  Anti-Submarine         Anti-Submarine         Maritime patrol aircraft crews search for,       LFM, LFH, MFM........           80          560  Northeast Range
                             Warfare.               Warfare Tracking       track, and detect submarines.                                                                     Complexes.
                                                    Exercise--Maritime
                                                    Patrol Aircraft.
Acoustic..................  Anti-Submarine         Anti-Submarine         Maritime patrol aircraft crews search for,       LFM, LFH, MFM........          155        1,085  Virginia Capes Range
                             Warfare.               Warfare Tracking       track, and detect submarines.                                                                     Complex.
                                                    Exercise--Maritime
                                                    Patrol Aircraft.
Acoustic..................  Anti-Submarine         Anti-Submarine         Surface ship crews search for, track, and        MFH, MF1, MF1C,                  5           35  Gulf Range Complex.
                             Warfare.               Warfare Tracking       detect submarines. Exercise torpedoes may be     Broadband (MF to HF).
                                                    Exercise--Ship.        used during this event.

[[Page 19868]]

 
Acoustic..................  Anti-Submarine         Anti-Submarine         Surface ship crews search for, track, and        MFH, MF1, MF1C,                290        2,030  Jacksonville Range
                             Warfare.               Warfare Tracking       detect submarines. Exercise torpedoes may be     Broadband (MF to HF).                            Complex.
                                                    Exercise--Ship.        used during this event.
Acoustic..................  Anti-Submarine         Anti-Submarine         Surface ship crews search for, track, and        MFH, MF1, MF1C,                 33          231  Navy Cherry Point
                             Warfare.               Warfare Tracking       detect submarines. Exercise torpedoes may be     Broadband (MF to HF).                            Range Complex.
                                                    Exercise--Ship.        used during this event.
Acoustic..................  Anti-Submarine         Anti-Submarine         Surface ship crews search for, track, and        MFH, MF1, MF1C,                  5           35  Northeast Range
                             Warfare.               Warfare Tracking       detect submarines. Exercise torpedoes may be     Broadband (MF to HF).                            Complexes.
                                                    Exercise--Ship.        used during this event.
Acoustic..................  Anti-Submarine         Anti-Submarine         Surface ship crews search for, track, and        MFH, MF1, MF1C,                 55          385  Other AFTT Areas.
                             Warfare.               Warfare Tracking       detect submarines. Exercise torpedoes may be     Broadband (MF to HF).
                                                    Exercise--Ship.        used during this event.
Acoustic..................  Anti-Submarine         Anti-Submarine         Surface ship crews search for, track, and        MFH, MF1, MF1C,                120          840  Virginia Capes Range
                             Warfare.               Warfare Tracking       detect submarines. Exercise torpedoes may be     Broadband (MF to HF).                            Complex.
                                                    Exercise--Ship.        used during this event.
Acoustic..................  Anti-Submarine         Anti-Submarine         Submarine crews search for, track, and detect    LFH, MFH, HFH........           13           91  Jacksonville Range
                             Warfare.               Warfare Tracking       submarines.                                                                                       Complex.
                                                    Exercise--Submarine.
Acoustic..................  Anti-Submarine         Anti-Submarine         Submarine crews search for, track, and detect    LFH, MFH, HFH........            1            7  Navy Cherry Point
                             Warfare.               Warfare Tracking       submarines.                                                                                       Range Complex.
                                                    Exercise--Submarine.
Acoustic..................  Anti-Submarine         Anti-Submarine         Submarine crews search for, track, and detect    LFH, MFH, HFH........           18          126  Northeast Range
                             Warfare.               Warfare Tracking       submarines.                                                                                       Complexes.
                                                    Exercise--Submarine.
Acoustic..................  Anti-Submarine         Anti-Submarine         Submarine crews search for, track, and detect    LFH, MFH, HFH........           46          308  Other AFTT Areas.
                             Warfare.               Warfare Tracking       submarines.
                                                    Exercise--Submarine.
Acoustic..................  Anti-Submarine         Anti-Submarine         Submarine crews search for, track, and detect    LFH, MFH, HFH........            6           42  Virginia Capes Range
                             Warfare.               Warfare Tracking       submarines.                                                                                       Complex.
                                                    Exercise--Submarine.
Acoustic..................  Expeditionary Warfare  Port Damage Repair...  Navy and Coast Guard Expeditionary forces train  Pile driving.........            4           28  Gulfport, MS.
                                                                           to repair critical port facilities.
Acoustic..................  Mine Warfare.........  Airborne Mine          Helicopter aircrew detect mines using towed or   HFH..................          290        2,030  Gulf Range Complex.
                                                    Countermeasures--Min   laser mine detection systems.
                                                    e Detection.
Acoustic..................  Mine Warfare.........  Airborne Mine          Helicopter aircrew detect mines using towed or   HFH..................          275        1,925  Jacksonville Range
                                                    Countermeasures--Min   laser mine detection systems.                                                                     Complex.
                                                    e Detection.
Acoustic..................  Mine Warfare.........  Airborne Mine          Helicopter aircrew detect mines using towed or   HFH..................          187        1,309  Key West Range
                                                    Countermeasures--Min   laser mine detection systems.                                                                     Complex.
                                                    e Detection.
Acoustic..................  Mine Warfare.........  Airborne Mine          Helicopter aircrew detect mines using towed or   HFH..................          321        2,247  Navy Cherry Point
                                                    Countermeasures--Min   laser mine detection systems.                                                                     Range Complex.
                                                    e Detection.
Acoustic..................  Mine Warfare.........  Airborne Mine          Helicopter aircrew detect mines using towed or   HFH..................        1,420        9,940  Virginia Capes Range
                                                    Countermeasures--Min   laser mine detection systems.                                                                     Complex.
                                                    e Detection.
Acoustic..................  Mine Warfare.........  Civilian Port          Coast Guard and Navy Maritime security           MFH, HFM, HFH........          0-1            4  Boston, MA;
                                                    Defense--Homeland      personnel train to protect civilian ports and                                                     Beaumont, TX;
                                                    Security Anti-         harbors against enemy efforts to interfere                                                        Corpus Christi, TX;
                                                    Terrorism/Force        with access to those ports.                                                                       Delaware Bay, DE;
                                                    Protection Exercises.                                                                                                    Earle, NJ; Hampton
                                                                                                                                                                             Roads, VA; Kings
                                                                                                                                                                             Bay, GA; Mayport,
                                                                                                                                                                             FL; Morehead City,
                                                                                                                                                                             NC; Port Canaveral,
                                                                                                                                                                             FL; Savannah, GA;
                                                                                                                                                                             Tampa, FL;
                                                                                                                                                                             Wilmington, NC.

[[Page 19869]]

 
Acoustic and Explosive....  Mine Warfare.........  Mine Countermeasures-- Ship, small boat, and helicopter crews locate    HFM, E4..............         * 66        * 462  Gulf Range Complex.
                                                    Mine Neutralization--  and disable mines using remotely operated
                                                    Remotely Operated      underwater vehicles. All events include
                                                    Vehicles.              acoustic sources, only a fraction involve
                                                                           explosives.
Acoustic and Explosive....  Mine Warfare.........  Mine Countermeasures-- Ship, small boat, and helicopter crews locate    HFM, E4..............           36          252  Jacksonville Range
                                                    Mine Neutralization--  and disable mines using remotely operated                                                         Complex.
                                                    Remotely Operated      underwater vehicles. All events include
                                                    Vehicles.              acoustic sources, only a fraction involve
                                                                           explosives.
Acoustic and Explosive....  Mine Warfare.........  Mine Countermeasures-- Ship, small boat, and helicopter crews locate    HFM, E4..............           10           70  Key West Range
                                                    Mine Neutralization--  and disable mines using remotely operated                                                         Complex.
                                                    Remotely Operated      underwater vehicles. All events include
                                                    Vehicles.              acoustic sources, only a fraction involve
                                                                           explosives.
Acoustic and Explosive....  Mine Warfare.........  Mine Countermeasures-- Ship, small boat, and helicopter crews locate    HFM, E4..............         * 36        * 252  Navy Cherry Point
                                                    Mine Neutralization--  and disable mines using remotely operated                                                         Range Complex.
                                                    Remotely Operated      underwater vehicles. All events include
                                                    Vehicles.              acoustic sources, only a fraction involve
                                                                           explosives.
Acoustic and Explosive....  Mine Warfare.........  Mine Countermeasures-- Ship, small boat, and helicopter crews locate    HFM, E4..............        * 315      * 2,205  Virginia Capes Range
                                                    Mine Neutralization--  and disable mines using remotely operated                                                         Complex.
                                                    Remotely Operated      underwater vehicles. All events include
                                                    Vehicles.              acoustic sources, only a fraction involve
                                                                           explosives.
Acoustic..................  Mine Warfare.........  Mine Countermeasures-- Ship crews detect and avoid mines while          HFH..................           22        * 462  Gulf Range Complex.
                                                    Ship Sonar.            navigating restricted areas or channels using
                                                                           active sonar.
Acoustic..................  Mine Warfare.........  Mine Countermeasures-- Ship crews detect and avoid mines while          HFH..................           53          252  Jacksonville Range
                                                    Ship Sonar.            navigating restricted areas or channels using                                                     Complex.
                                                                           active sonar.
Acoustic..................  Mine Warfare.........  Mine Countermeasures-- Ship crews detect and avoid mines while          HFH..................           53           70  Virginia Capes Range
                                                    Ship Sonar.            navigating restricted areas or channels using                                                     Complex.
                                                                           active sonar.
Explosive.................  Mine Warfare.........  Mine Neutralization    Personnel disable threat mines using explosive   E6...................         * 96        * 672  Gulf Range Complex.
                                                    Explosive Ordnance     charges.
                                                    Disposal.
Explosive.................  Mine Warfare.........  Mine Neutralization    Personnel disable threat mines using explosive   E5, E6...............        * 100        * 700  Jacksonville Range
                                                    Explosive Ordnance     charges.                                                                                          Complex.
                                                    Disposal.
Explosive.................  Mine Warfare.........  Mine Neutralization    Personnel disable threat mines using explosive   E5, E6, E7...........         * 30        * 210  Key West Range
                                                    Explosive Ordnance     charges.                                                                                          Complex.
                                                    Disposal.
Explosive.................  Mine Warfare.........  Mine Neutralization    Personnel disable threat mines using explosive   E5...................        * 176      * 1,232  Key West Range
                                                    Explosive Ordnance     charges.                                                                                          Complex Inshore.
                                                    Disposal.
Explosive.................  Mine Warfare.........  Mine Neutralization    Personnel disable threat mines using explosive   E6...................         * 86        * 602  Navy Cherry Point
                                                    Explosive Ordnance     charges.                                                                                          Range Complex.
                                                    Disposal.
Explosive.................  Mine Warfare.........  Mine Neutralization    Personnel disable threat mines using explosive   E5, E6, E7...........        * 325      * 2,275  Virginia Capes Range
                                                    Explosive Ordnance     charges.                                                                                          Complex.
                                                    Disposal.
Acoustic..................  Mine Warfare.........  Submarine Mine Laying  Submarine crews or UUVs deploy exercise mobile   MFM, HFL, HFM, VHFL..            2           14  Jacksonville Range
                                                                           mines or mines.                                                                                   Complex.
Acoustic..................  Mine Warfare.........  Surface Ship Object    Ship crews detect and avoid mines while          MF1K.................           76          532  Jacksonville Range
                                                    Detection.             navigating restricted areas or channels using                                                     Complex.
                                                                           active sonar.
Acoustic..................  Mine Warfare.........  Surface Ship Object    Ship crews detect and avoid mines while          MF1K.................          162        1,134  Virginia Capes Range
                                                    Detection.             navigating restricted areas or channels using                                                     Complex.
                                                                           active sonar.
Explosive.................  Surface Warfare......  Bombing Exercise Air-  Fixed-wing aircrew deliver bombs against         E9, E10..............         * 47        * 329  Gulf Range Complex.
                                                    to-Surface.            surface targets.
Explosive.................  Surface Warfare......  Bombing Exercise Air-  Fixed-wing aircrew deliver bombs against         E9, E10..............        * 260       1,820*  Jacksonville Range
                                                    to-Surface.            surface targets.                                                                                  Complex.
Explosive.................  Surface Warfare......  Bombing Exercise Air-  Fixed-wing aircrew deliver bombs against         E9, E10, E12.........        * 272      * 1,904  Virginia Capes Range
                                                    to-Surface.            surface targets.                                                                                  Complex.
Explosive.................  Surface Warfare......  Gunnery Exercise       Small boat crews fire medium-caliber guns at     E1...................        * 404      * 2,828  Virginia Capes Range
                                                    Surface-to-Surface     surface targets.                                                                                  Complex.
                                                    Boat Medium-Caliber.

[[Page 19870]]

 
Explosive.................  Surface Warfare......  Gunnery Exercise       Surface ship crews fire large-caliber guns at    E3, E5...............          * 8         * 56  Gulf Range Complex.
                                                    Surface-to-Surface     surface targets.
                                                    Ship Large-Caliber.
Explosive.................  Surface Warfare......  Gunnery Exercise       Surface ship crews fire large-caliber guns at    E3, E5...............         * 46        * 322  Jacksonville Range
                                                    Surface-to-Surface     surface targets.                                                                                  Complex.
                                                    Ship Large-Caliber.
Explosive.................  Surface Warfare......  Gunnery Exercise       Surface ship crews fire large-caliber guns at    E3, E5...............         * 34        * 238  Navy Cherry Point
                                                    Surface-to-Surface     surface targets.                                                                                  Range Complex.
                                                    Ship Large-Caliber.
Explosive.................  Surface Warfare......  Gunnery Exercise       Surface ship crews fire large-caliber guns at    E3, E5...............          * 9         * 63  Other AFTT Areas.
                                                    Surface-to-Surface     surface targets.
                                                    Ship Large-Caliber.
Explosive.................  Surface Warfare......  Gunnery Exercise       Surface ship crews fire large-caliber guns at    E3, E5...............         * 63         *441  Virginia Capes Range
                                                    Surface-to-Surface     surface targets.                                                                                  Complex.
                                                    Ship Large-Caliber.
Explosive.................  Surface Warfare......  Integrated Live Fire   Naval forces defend against a swarm of surface   E10..................            2           14  Jacksonville Range
                                                    Exercise.              threats (ships or small boats) with bombs,                                                        Complex.
                                                                           missiles, rockets, and small-, medium- and
                                                                           large-caliber guns.
Explosive.................  Surface Warfare......  Integrated Live Fire   Naval forces defend against a swarm of surface   E10..................            2           14  Virginia Capes Range
                                                    Exercise.              threats (ships or small boats) with bombs,                                                        Complex.
                                                                           missiles, rockets, and small-, medium- and
                                                                           large-caliber guns.
Explosive.................  Surface Warfare......  Missile Exercise Air-  Helicopter aircrew fire both precision-guided    E3...................           10           70  Gulf Range Complex.
                                                    to-Surface--Rocket.    and unguided rockets at surface targets.
Explosive.................  Surface Warfare......  Missile Exercise Air-  Helicopter aircrew fire both precision-guided    E3...................          115          805  Jacksonville Range
                                                    to-Surface--Rocket.    and unguided rockets at surface targets.                                                          Complex.
Explosive.................  Surface Warfare......  Missile Exercise Air-  Helicopter aircrew fire both precision-guided    E3...................           15          105  Navy Cherry Point
                                                    to-Surface--Rocket.    and unguided rockets at surface targets.                                                          Range Complex.
Explosive.................  Surface Warfare......  Missile Exercise Air-  Helicopter aircrew fire both precision-guided    E3...................          100          700  Virginia Capes Range
                                                    to-Surface--Rocket.    and unguided rockets at surface targets.                                                          Complex.
Explosive.................  Surface Warfare......  Missile Exercise Air-  Fixed-wing and helicopter aircrew fire air-to-   E6, E8, E9...........           81          567  Jacksonville Range
                                                    to-Surface.            surface missiles at surface targets.                                                              Complex.
Explosive.................  Surface Warfare......  Missile Exercise Air-  Fixed-wing and helicopter aircrew fire air-to-   E6...................            8           56  Key West Range
                                                    to-Surface.            surface missiles at surface targets.                                                              Complex.
Explosive.................  Surface Warfare......  Missile Exercise Air-  Fixed-wing and helicopter aircrew fire air-to-   E6...................           72          504  Navy Cherry Point
                                                    to-Surface.            surface missiles at surface targets.                                                              Range Complex.
Explosive.................  Surface Warfare......  Missile Exercise Air-  Fixed-wing and helicopter aircrew fire air-to-   E6, E8, E9...........           83          581  Virginia Capes Range
                                                    to-Surface.            surface missiles at surface targets.                                                              Complex.
Explosive.................  Surface Warfare......  Missile Exercise       Surface ship crews defend against surface        E6, E9...............           19          133  Jacksonville Range
                                                    Surface-to-Surface.    threats (ships or small boats) and engage them                                                    Complex.
                                                                           with missiles.
Explosive.................  Surface Warfare......  Missile Exercise       Surface ship crews defend against surface        E6, E9...............           15          105  Virginia Capes Range
                                                    Surface-to-Surface.    threats (ships or small boats) and engage them                                                    Complex.
                                                                           with missiles.
Acoustic and Explosive....  Surface Warfare......  Sinking Exercise.....  Aircraft, ship, cutter, and submarine crews      HFH, E5, E8, E9, E11.            1            7  SINKEX Box.
                                                                           deliberately sink a seaborne target, usually a
                                                                           decommissioned ship made environmentally safe
                                                                           for sinking according to U.S. Environmental
                                                                           Protection Agency standards, with a variety of
                                                                           ordnance.
Acoustic..................  Other Training         Submarine Navigation.  Submarine crews operate sonar for navigation     MFH..................           29          203  Jacksonville Range
                             Activities.                                   and detection while transiting into and out of                                                    Complex.
                                                                           port during reduced visibility.
Acoustic..................  Other Training         Submarine Navigation.  Submarine crews operate sonar for navigation     MFH..................          169        1,183  Northeast Range
                             Activities.                                   and detection while transiting into and out of                                                    Complexes.
                                                                           port during reduced visibility.

[[Page 19871]]

 
Acoustic..................  Other Training         Submarine Navigation.  Submarine crews operate sonar for navigation     MFH..................           84          588  Virginia Capes Range
                             Activities.                                   and detection while transiting into and out of                                                    Complex, Virginia
                                                                           port during reduced visibility.                                                                   Capes Range Complex
                                                                                                                                                                             Inshore.
Acoustic..................  Other Training         Submarine Sonar        Maintenance of submarine sonar and other system  MFH..................            4           28  Jacksonville Range
                             Activities.            Maintenance and        checks are conducted pierside or at sea.                                                          Complex.
                                                    Systems Checks.
Acoustic..................  Other Training         Submarine Sonar        Maintenance of submarine sonar and other system  MFH..................            2           14  Port Canaveral, FL.
                             Activities.            Maintenance and        checks are conducted pierside or at sea.
                                                    Systems Checks.
Acoustic..................  Other Training         Submarine Sonar        Maintenance of submarine sonar and other system  MFH..................            2           14  NSB Kings Bay.
                             Activities.            Maintenance and        checks are conducted pierside or at sea.
                                                    Systems Checks.
Acoustic..................  Other Training         Submarine Sonar        Maintenance of submarine sonar and other system  MFH..................           66          462  Northeast Range
                             Activities.            Maintenance and        checks are conducted pierside or at sea.                                                          Complexes.
                                                    Systems Checks.
Acoustic..................  Other Training         Submarine Sonar        Maintenance of submarine sonar and other system  MFH..................           66          462  NSB New London.
                             Activities.            Maintenance and        checks are conducted pierside or at sea.
                                                    Systems Checks.
Acoustic..................  Other Training         Submarine Sonar        Maintenance of submarine sonar and other system  MFH..................           12           84  Other AFTT Areas.
                             Activities.            Maintenance and        checks are conducted pierside or at sea.
                                                    Systems Checks.
Acoustic..................  Other Training         Submarine Sonar        Maintenance of submarine sonar and other system  MFH..................           34          238  Virginia Capes Range
                             Activities.            Maintenance and        checks are conducted pierside or at sea.                                                          Complex.
                                                    Systems Checks.
Acoustic..................  Other Training         Submarine Sonar        Maintenance of submarine sonar and other system  MFH..................           34          238  NS Norfolk.
                             Activities.            Maintenance and        checks are conducted pierside or at sea.
                                                    Systems Checks.
Acoustic..................  Other Training         Submarine Under Ice    Submarine crews operate sonar while transiting   HFH..................            3           21  Jacksonville Range
                             Activities.            Certification.         under ice. Ice conditions are simulated during                                                    Complex.
                                                                           training and certification events.
Acoustic..................  Other Training         Submarine Under Ice    Submarine crews operate sonar while transiting   HFH..................            3           21  Navy Cherry Point
                             Activities.            Certification.         under ice. Ice conditions are simulated during                                                    Range Complex.
                                                                           training and certification events.
Acoustic..................  Other Training         Submarine Under Ice    Submarine crews operate sonar while transiting   HFH..................            9           63  Northeast Range
                             Activities.            Certification.         under ice. Ice conditions are simulated during                                                    Complexes.
                                                                           training and certification events.
Acoustic..................  Other Training         Submarine Under Ice    Submarine crews operate sonar while transiting   HFH..................            9           63  Virginia Capes Range
                             Activities.            Certification.         under ice. Ice conditions are simulated during                                                    Complex.
                                                                           training and certification events.
Acoustic..................  Other Training         Surface Ship Sonar     Maintenance of surface ship sonar and other      MF1, MF1K............           50          350  Jacksonville Range
                             Activities.            Maintenance and        system checks are conducted pierside or at                                                        Complex.
                                                    Systems Checks.        sea.
Acoustic..................  Other Training         Surface Ship Sonar     Maintenance of surface ship sonar and other      MF1, MF1K............           50          350  NS Mayport.
                             Activities.            Maintenance and        system checks are conducted pierside or at
                                                    Systems Checks.        sea.
Acoustic..................  Other Training         Surface Ship Sonar     Maintenance of surface ship sonar and other      MF1, MF1K............          120          840  Navy Cherry Point
                             Activities.            Maintenance and        system checks are conducted pierside or at                                                        Range Complex.
                                                    Systems Checks.        sea.
Acoustic..................  Other Training         Surface Ship Sonar     Maintenance of surface ship sonar and other      MF1, MF1K............          175        1,225  NS Norfolk.
                             Activities.            Maintenance and        system checks are conducted pierside or at
                                                    Systems Checks.        sea.
Acoustic..................  Other Training         Surface Ship Sonar     Maintenance of surface ship sonar and other      MF1, MF1K............           18          126  Other AFTT Areas.
                             Activities.            Maintenance and        system checks are conducted pierside or at
                                                    Systems Checks.        sea.
Acoustic..................  Other Training         Surface Ship Sonar     Maintenance of surface ship sonar and other      MF1, MF1K............          175        1,225  Virginia Capes Range
                             Activities.            Maintenance and        system checks are conducted pierside or at                                                        Complex.
                                                    Systems Checks.        sea.
Acoustic..................  Other Training         Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            10           70  Gulf Range Complex.
                             Activities.            Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.

[[Page 19872]]

 
Acoustic..................  Other Training         Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            22          154  Jacksonville Range
                             Activities.            Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,                                      Complex.
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.
Acoustic..................  Other Training         Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            10           70  Navy Cherry Point
                             Activities.            Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,                                      Range Complex.
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.
Acoustic..................  Other Training         Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            12           84  Northeast Range
                             Activities.            Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,                                      Complexes.
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.
Acoustic..................  Other Training         Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            32          224  Virginia Capes Range
                             Activities.            Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,                                      Complex.
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.
Acoustic..................  Other Training         Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            21          147  Virginia Capes Range
                             Activities.            Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,                                      Complex Inshore.
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: AFTT: Atlantic Fleet Training and Testing; DE: Delaware; FL: Florida; GA: Georgia; JEB: Joint Expeditionary Base; MA: Massachusetts; MS: Mississippi; NC: North Carolina; NJ: New Jersey;
  NS: Naval Station; NSB: Naval Submarine Base; SINKEX: Sinking Exercise; TX: Texas; VA: Virginia. The Gulf Range Complex includes geographically separated areas throughout the Gulf of
  America.
* Only a small subset of these activities include explosive ordnance.


                                                      Table 6--Proposed Coast Guard Training Activities Analyzed Within the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                   Number of    Number of
     Stressor category          Activity type          Activity name                        Description                          Source bin        activities   activities        Location
                                                                                                                                                     1-year       7-year
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Explosive.................  Surface Warfare......  Gunnery Exercise       Surface ship crews fire large-caliber guns at    E3...................         * 29          203  Gulf Range complex.
                                                    Surface-to-Surface     surface targets.
                                                    Ship Large-Caliber.
Explosive.................  Surface Warfare......  Gunnery Exercise       Surface ship crews fire large-caliber guns at    E3...................           15          105  Jacksonville Range
                                                    Surface-to-Surface     surface targets.                                                                                  Complex.
                                                    Ship Large-Caliber.
Explosive.................  Surface Warfare......  Gunnery Exercise       Surface ship crews fire large-caliber guns at    E3...................           10           70  Navy Cherry Point
                                                    Surface-to-Surface     surface targets.                                                                                  Range Complex.
                                                    Ship Large-Caliber.
Explosive.................  Surface Warfare......  Gunnery Exercise       Surface ship crews fire large-caliber guns at    E3...................         * 15          105  Northeast Range
                                                    Surface-to-Surface     surface targets.                                                                                  Complexes.
                                                    Ship Large-Caliber.

[[Page 19873]]

 
Explosive.................  Surface Warfare......  Gunnery Exercise       Surface ship crews fire large-caliber guns at    E3...................         * 20          140  Virginia Capes Range
                                                    Surface-to-Surface     surface targets.                                                                                  Complex.
                                                    Ship Large-Caliber.
Acoustic..................  Surface Warfare......  Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            10           70  Gulf Range Complex.
                                                    Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.
Acoustic..................  Surface Warfare......  Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            10           70  Jacksonville Range
                                                    Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,                                      Complex.
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.
Acoustic..................  Surface Warfare......  Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            10           70  Navy Cherry Point
                                                    Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,                                      Range Complex.
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.
Acoustic..................  Surface Warfare......  Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            20          140  Virginia Capes Range
                                                    Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,                                      Complex.
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.
Acoustic..................  Surface Warfare......  Unmanned Underwater    Unmanned underwater vehicle certification        MFH, HFL, HFM, VHFL,            20          140  Virginia Capes Range
                                                    Vehicle Training--     involves training with unmanned platforms to     VHFM, VHFH,                                      Complex Inshore.
                                                    Certification and      ensure submarine crew proficiency. Tactical      Broadband (MF to
                                                    Development.           development involves training with various       HF), Broadband (HF
                                                                           payloads, for multiple purposes to ensure that   to VHF).
                                                                           the systems can be employed effectively in an
                                                                           operational environment.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: The Gulf Range Complex includes geographically separated areas throughout the Gulf of America.
* Only a small subset of these activities include explosive ordnance.


[[Page 19874]]

Overview of Testing Activities Within the Study Area
    While this proposed rule includes an evaluation of proposed 
training activities by both the Navy and Coast Guard, all testing 
activities evaluated in this proposed rule would only be conducted by 
the Navy. The Navy's research and acquisition community engages in a 
broad spectrum of testing activities, some of which ultimately support 
both Action Proponents. These activities include, but are not limited 
to, basic and applied scientific research and technology development; 
testing, evaluation, and maintenance of systems (e.g., missiles, radar, 
and sonar) and platforms (e.g., surface ships, submarines, and 
aircraft); and acquisition of systems and platforms to support Navy 
missions and give a technological edge over adversaries. The individual 
commands within the research and acquisition community included in the 
application are Naval Air Systems Command (NAVAIR), Naval Sea Systems 
Command (NAVSEA), and the Office of Naval Research (ONR).
    The Action Proponents operate in an ever-changing strategic, 
tactical, financially-constrained, and time-constrained environment. 
Testing activities occur in response to emerging science or fleet 
operational needs. For example, future Navy studies to develop a better 
understanding of ocean currents may be designed based on advancements 
made by non-government researchers not yet published in the scientific 
literature. Similarly, future but yet unknown Navy and Coast Guard 
operations within a specific geographic area may require development of 
modified Navy assets to address local conditions. Such modifications 
must be tested in the field to ensure they meet fleet needs and 
requirements. Accordingly, generic descriptions of some of these 
activities are the best that can be articulated in a long-term, 
comprehensive document.
    Some testing activities are similar to training activities 
conducted by the fleet (e.g., both the fleet and the research and 
acquisition community fire torpedoes). While the firing of a torpedo 
might look identical to an observer, the difference is in the purpose 
of the firing. The fleet might fire the torpedo to practice the 
procedures for such a firing, whereas the research and acquisition 
community might be assessing a new torpedo guidance technology or 
testing it to ensure the torpedo meets performance specifications and 
operational requirements.
    NAVAIR testing activities support its mission to provide full life 
cycle support of naval aviation aircraft, weapons, and systems to be 
operated by the Navy and Coast Guard. NAVAIR activities closely follow 
Navy primary mission areas, such as the testing of airborne mine 
warfare and anti-submarine warfare weapons and systems. NAVAIR 
activities include, but are not limited to, the testing of new aircraft 
platforms, weapons, and systems that have not yet been integrated into 
the Navy fleet and Coast Guard. In addition to testing new platforms 
and weapon systems, most aircraft and weapon systems that have been 
integrated into the fleet also require follow-on testing throughout 
their lifecycle in conjunction with maintenance and upgrades, such as 
software revisions, to ensure that they function as designed. While 
these types of activities do not fall within one of the fleet primary 
mission areas, most NAVAIR testing activities can be easily correlated 
to fleet training activities. Some testing activities may be conducted 
in different locations and in a different manner than similar fleet 
training activities and, therefore, the analysis for those events and 
the potential environmental effects may differ. Table 7 summarizes the 
proposed testing activities for NAVAIR analyzed within the AFTT Study 
Area.

[[Page 19875]]



                                                         Table 7--Proposed NAVAIR Testing Activities Analyzed Within the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                   Number of    Number of
     Stressor category          Activity type          Activity name                        Description                          Source bin        activities   activities        Location
                                                                                                                                                     1-year       7-year
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic..................  Anti-Submarine         Anti-Submarine         The test evaluates the sensors and systems used  LFM, LFH, MFM, HFM...           15          105  Gulf Range Complex.
                             Warfare.               Warfare Tracking       by fixed-wing aircraft to detect and track
                                                    Test (Fixed-Wing).     submarines and to ensure that aircraft systems
                                                                           used to deploy the tracking systems perform to
                                                                           specifications and meet operational
                                                                           requirements.
Acoustic..................  Anti-Submarine         Anti-Submarine         The test evaluates the sensors and systems used  LFM, LFH, MFM, HFM...           19          133  Jacksonville Range
                             Warfare.               Warfare Tracking       by fixed-wing aircraft to detect and track                                                        Complex.
                                                    Test (Fixed-Wing).     submarines and to ensure that aircraft systems
                                                                           used to deploy the tracking systems perform to
                                                                           specifications and meet operational
                                                                           requirements.
Acoustic..................  Anti-Submarine         Anti-Submarine         The test evaluates the sensors and systems used  LFM, LFH, MFM, HFM...           12           84  Key West Range
                             Warfare.               Warfare Tracking       by fixed-wing aircraft to detect and track                                                        Complex.
                                                    Test (Fixed-Wing).     submarines and to ensure that aircraft systems
                                                                           used to deploy the tracking systems perform to
                                                                           specifications and meet operational
                                                                           requirements.
Acoustic..................  Anti-Submarine         Anti-Submarine         The test evaluates the sensors and systems used  LFM, LFH, MFM, HFM...           15          105  Navy Cherry Point
                             Warfare.               Warfare Tracking       by fixed-wing aircraft to detect and track                                                        Range Complex.
                                                    Test (Fixed-Wing).     submarines and to ensure that aircraft systems
                                                                           used to deploy the tracking systems perform to
                                                                           specifications and meet operational
                                                                           requirements.
Acoustic..................  Anti-Submarine         Anti-Submarine         The test evaluates the sensors and systems used  LFM, LFH, MFM, HFM...           45          315  Northeast Range
                             Warfare.               Warfare Tracking       by fixed-wing aircraft to detect and track                                                        Complexes.
                                                    Test (Fixed-Wing).     submarines and to ensure that aircraft systems
                                                                           used to deploy the tracking systems perform to
                                                                           specifications and meet operational
                                                                           requirements.
Acoustic..................  Anti-Submarine         Anti-Submarine         The test evaluates the sensors and systems used  LFM, LFH, MFM, HFM...           25          175  SINKEX Box.
                             Warfare.               Warfare Tracking       by fixed-wing aircraft to detect and track
                                                    Test (Fixed-Wing).     submarines and to ensure that aircraft systems
                                                                           used to deploy the tracking systems perform to
                                                                           specifications and meet operational
                                                                           requirements.
Acoustic..................  Anti-Submarine         Anti-Submarine         The test evaluates the sensors and systems used  LFM, LFH, MFM, HFM...           25          175  Virginia Capes Range
                             Warfare.               Warfare Tracking       by fixed-wing aircraft to detect and track                                                        Complex.
                                                    Test (Fixed-Wing).     submarines and to ensure that aircraft systems
                                                                           used to deploy the tracking systems perform to
                                                                           specifications and meet operational
                                                                           requirements.
Acoustic..................  Anti-Submarine         Anti-Submarine         This event is similar to the training event      HFH..................        20-43          209  Jacksonville Range
                             Warfare.               Warfare Torpedo Test.  torpedo exercise. Test evaluates anti-                                                            Complex.
                                                                           submarine warfare systems onboard rotary-wing
                                                                           and fixed-wing aircraft and the ability to
                                                                           search for, detect, classify, localize, track,
                                                                           and attack a submarine or similar target.
Acoustic..................  Anti-Submarine         Anti-Submarine         This event is similar to the training event      HFH..................       40-121          523  Virginia Capes Range
                             Warfare.               Warfare Torpedo Test.  torpedo exercise. Test evaluates anti-                                                            Complex.
                                                                           submarine warfare systems onboard rotary-wing
                                                                           and fixed-wing aircraft and the ability to
                                                                           search for, detect, classify, localize, track,
                                                                           and attack a submarine or similar target.
Acoustic..................  Anti-Submarine         Anti-Submarine         This event is similar to the training event      MFM, MFH.............            6           42  Gulf Range Complex.
                             Warfare.               Warfare Tracking       anti-submarine tracking exercise-helicopter.
                                                    Test (Rotary-Wing).    The test evaluates the sensors and systems
                                                                           used to detect and track submarines and to
                                                                           ensure that helicopter systems used to deploy
                                                                           the tracking systems perform to
                                                                           specifications.
Acoustic..................  Anti-Submarine         Anti-Submarine         This event is similar to the training event      MFM, MFH.............           23          161  Jacksonville Range
                             Warfare.               Warfare Tracking       anti-submarine tracking exercise-helicopter.                                                      Complex.
                                                    Test (Rotary-Wing).    The test evaluates the sensors and systems
                                                                           used to detect and track submarines and to
                                                                           ensure that helicopter systems used to deploy
                                                                           the tracking systems perform to
                                                                           specifications.

[[Page 19876]]

 
Acoustic..................  Anti-Submarine         Anti-Submarine         This event is similar to the training event      MFM, MFH.............           27          189  Key West Range
                             Warfare.               Warfare Tracking       anti-submarine tracking exercise-helicopter.                                                      Complex.
                                                    Test (Rotary-Wing).    The test evaluates the sensors and systems
                                                                           used to detect and track submarines and to
                                                                           ensure that helicopter systems used to deploy
                                                                           the tracking systems perform to
                                                                           specifications.
Acoustic..................  Anti-Submarine         Anti-Submarine         This event is similar to the training event      MFM, MFH.............          110          770  Northeast Range
                             Warfare.               Warfare Tracking       anti-submarine tracking exercise-helicopter.                                                      Complexes.
                                                    Test (Rotary-Wing).    The test evaluates the sensors and systems
                                                                           used to detect and track submarines and to
                                                                           ensure that helicopter systems used to deploy
                                                                           the tracking systems perform to
                                                                           specifications.
Acoustic..................  Anti-Submarine         Anti-Submarine         This event is similar to the training event      MFM, MFH.............          280        1,960  Virginia Capes Range
                             Warfare.               Warfare Tracking       anti-submarine tracking exercise-helicopter.                                                      Complex.
                                                    Test (Rotary-Wing).    The test evaluates the sensors and systems
                                                                           used to detect and track submarines and to
                                                                           ensure that helicopter systems used to deploy
                                                                           the tracking systems perform to
                                                                           specifications.
Acoustic..................  Anti-Submarine         Kilo Dip Test........  Functional check of a helicopter deployed        MFH..................            6           42  Gulf Range Complex.
                             Warfare.                                      dipping sonar system prior to conducting a
                                                                           testing or training event using the dipping
                                                                           sonar system.
Acoustic..................  Anti-Submarine         Kilo Dip Test........  Functional check of a helicopter deployed        MFH..................            6           42  Jacksonville Range
                             Warfare.                                      dipping sonar system prior to conducting a                                                        Complex.
                                                                           testing or training event using the dipping
                                                                           sonar system.
Acoustic..................  Anti-Submarine         Kilo Dip Test........  Functional check of a helicopter deployed        MFH..................            6           42  Key West Range
                             Warfare.                                      dipping sonar system prior to conducting a                                                        Complex.
                                                                           testing or training event using the dipping
                                                                           sonar system.
Acoustic..................  Anti-Submarine         Kilo Dip Test........  Functional check of a helicopter deployed        MFH..................            4           28  Northeast Range
                             Warfare.                                      dipping sonar system prior to conducting a                                                        Complexes.
                                                                           testing or training event using the dipping
                                                                           sonar system.
Acoustic..................  Anti-Submarine         Kilo Dip Test........  Functional check of a helicopter deployed        MFH..................           40          280  Virginia Capes Range
                             Warfare.                                      dipping sonar system prior to conducting a                                                        Complex.
                                                                           testing or training event using the dipping
                                                                           sonar system.
Acoustic and Explosive....  Anti-Submarine         Sonobuoy Lot           Sonobuoys are deployed from surface vessels and  LFM, LFH, MFM, HFM           * 186      * 1,302  Key West Range
                             Warfare.               Acceptance Test.       aircraft to verify the integrity and             E1, E3.                                          Complex.
                                                                           performance of a lot or group of sonobuoys in
                                                                           advance of delivery to the fleet for
                                                                           operational use.
Acoustic..................  Mine Warfare.........  Airborne Dipping       A mine-hunting dipping sonar system that is      HFH..................           32          224  NSWC Panama City
                                                    Sonar Minehunting      deployed from a helicopter and uses high-                                                         Testing Range.
                                                    Test.                  frequency sonar for the detection and
                                                                           classification of bottom and moored mines.
Acoustic..................  Mine Warfare.........  Airborne Dipping       A mine-hunting dipping sonar system that is      HFH..................           40          280  Virginia Capes Range
                                                    Sonar Minehunting      deployed from a helicopter and uses high-                                                         Complex.
                                                    Test.                  frequency sonar for the detection and
                                                                           classification of bottom and moored mines.
Explosive.................  Mine Warfare.........  Airborne Mine          A test of the airborne mine neutralization       E4...................         * 27        * 189  NSWC Panama City
                                                    Neutralization         system evaluates the system's ability to                                                          Testing Range.
                                                    System Test.           detect and destroy mines from an airborne mine
                                                                           countermeasures capable helicopter. The
                                                                           airborne mine neutralization system uses up to
                                                                           four unmanned underwater vehicles equipped
                                                                           with high-frequency sonar, video cameras, and
                                                                           explosive and non-explosive neutralizers.

[[Page 19877]]

 
Explosive.................  Mine Warfare.........  Airborne Mine          A test of the airborne mine neutralization       E4...................         * 25        * 175  Virginia Capes Range
                                                    Neutralization         system evaluates the system's ability to                                                          Complex.
                                                    System Test.           detect and destroy mines from an airborne mine
                                                                           countermeasures capable helicopter. The
                                                                           airborne mine neutralization system uses up to
                                                                           four unmanned underwater vehicles equipped
                                                                           with high-frequency sonar, video cameras, and
                                                                           explosive and non-explosive neutralizers.
Acoustic..................  Mine Warfare.........  Airborne Minehunting   A mine-hunting system made up of sonobuoys is    MFM..................           26          182  NSWC Panama City
                                                    Test--Sonobuoy.        deployed from a helicopter. A field of                                                            Testing Range.
                                                                           sonobuoys, using high-frequency sonar, is used
                                                                           for detection and classification of bottom and
                                                                           moored mines.
Acoustic..................  Mine Warfare.........  Airborne Minehunting   A mine-hunting system made up of sonobuoys is    MFM..................           12           84  Virginia Capes Range
                                                    Test--Sonobuoy.        deployed from a helicopter. A field of                                                            Complex.
                                                                           sonobuoys, using high-frequency sonar, is used
                                                                           for detection and classification of bottom and
                                                                           moored mines.
Explosive.................  Surface Warfare......  Air-to-Surface         This event is similar to the training event      E1...................           55          385  Jacksonville Range
                                                    Gunnery Test.          gunnery exercise air-to-surface. Fixed-wing                                                       Complex.
                                                                           and rotary-wing aircrew evaluate new or
                                                                           enhanced aircraft guns against surface
                                                                           maritime targets to test that the gun, gun
                                                                           ammunition, or associated systems meet
                                                                           required specifications or to train aircrew in
                                                                           the operation of a new or enhanced weapons
                                                                           system.
Explosive.................  Surface Warfare......  Air-to-Surface         This event is similar to the training event      E1...................          140          980  Virginia Capes Range
                                                    Gunnery Test.          gunnery exercise air-to-surface. Fixed-wing                                                       Complex.
                                                                           and rotary-wing aircrew evaluate new or
                                                                           enhanced aircraft guns against surface
                                                                           maritime targets to test that the gun, gun
                                                                           ammunition, or associated systems meet
                                                                           required specifications or to train aircrew in
                                                                           the operation of a new or enhanced weapons
                                                                           system.
Explosive.................  Surface Warfare......  Air-to-Surface         This event is similar to the training event      E9...................            5           35  Gulf Range Complex.
                                                    Missile Test.          missile exercise air-to-surface. Test may
                                                                           involve both fixed-wing and rotary-wing
                                                                           aircraft launching missiles at surface
                                                                           maritime targets to evaluate the weapons
                                                                           system or as part of another systems
                                                                           integration test.
Explosive.................  Surface Warfare......  Air-to-Surface         This event is similar to the training event      E6...................         * 29        * 203  Jacksonville Range
                                                    Missile Test.          missile exercise air-to-surface. Test may                                                         Complex.
                                                                           involve both fixed-wing and rotary-wing
                                                                           aircraft launching missiles at surface
                                                                           maritime targets to evaluate the weapons
                                                                           system or as part of another systems
                                                                           integration test.
Explosive.................  Surface Warfare......  Air-to-Surface         This event is similar to the training event      E6...................        * 117        * 819  Virginia Capes Range
                                                    Missile Test.          missile exercise air-to-surface. Test may                                                         Complex.
                                                                           involve both fixed-wing and rotary-wing
                                                                           aircraft launching missiles at surface
                                                                           maritime targets to evaluate the weapons
                                                                           system or as part of another systems
                                                                           integration test.
Explosive.................  Surface Warfare......  Rocket Test..........  Rocket tests are conducted to evaluate the       E3...................           19          133  Jacksonville Range
                                                                           integration, accuracy, performance, and safe                                                      Complex.
                                                                           separation of guided and unguided 2.75-inch
                                                                           rockets fired from a hovering or forward
                                                                           flying helicopter or tilt rotor aircraft.
Explosive.................  Surface Warfare......  Rocket Test..........  Rocket tests are conducted to evaluate the       E3...................         * 35        * 245  Virginia Capes Range
                                                                           integration, accuracy, performance, and safe                                                      Complex.
                                                                           separation of guided and unguided 2.75-inch
                                                                           rockets fired from a hovering or forward
                                                                           flying helicopter or tilt rotor aircraft.

[[Page 19878]]

 
Acoustic..................  Other Testing          Undersea Range System  Following installation of a Navy underwater      MFM, HFM.............         4-20           76  Jacksonville Range
                             Activities.            Test.                  warfare training and testing range, tests of                                                      Complex.
                                                                           the nodes (components of the range) will be
                                                                           conducted to include node surveys and testing
                                                                           of node transmission functionality.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: NAVAIR: Naval Air Systems Command; NSWC: Naval Surface Warfare Center. The Gulf Range Complex includes geographically separated areas throughout the Gulf of America.
* Only a small subset of these activities include explosive ordnance.


[[Page 19879]]

    NAVSEA activities are aligned with its mission of new ship 
construction, life cycle management, and weapon systems development. 
NAVSEA activities include pierside and at-sea testing of vessel 
systems, including sonar, acoustic countermeasures, radars, launch 
systems, weapons, unmanned systems, and radio equipment; tests to 
determine how the vessel or Coast Guard Cutter performs at sea (sea 
trials); developmental and operational test and evaluation programs for 
new technologies and systems; and testing on all vessels and systems 
that have undergone overhaul or maintenance. In the application, 
pierside testing at Navy contractor shipyards would consist only of 
system testing. At-sea test firing of shipboard weapon systems, 
including guns, torpedoes, and missiles, is also conducted. Testing 
activities are conducted throughout the life of a vessel, from 
construction to verification of performance and mission capabilities, 
and further to deactivation from the fleet. Table 8 summarizes the 
proposed testing activities for the NAVSEA analyzed within the AFTT 
Study Area.
    One ship of each new class (or major upgrade) of combat ships 
constructed for the Navy typically undergoes an at-sea ship shock 
trial. A ship shock trial consists of a series of underwater 
detonations that send shock waves through the ship's hull to simulate 
near misses during combat. A shock trial allows the Navy to assess the 
survivability of the hull and ship's systems in a combat environment as 
well as the capability of the ship to protect the crew.

[[Page 19880]]



                                                         Table 8--Proposed NAVSEA Testing Activities Analyzed Within the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                   Number of    Number of
     Stressor category          Activity type          Activity name                        Description                          Source bin        activities   activities        Location
                                                                                                                                                     1-year       7-year
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic..................  Anti-Submarine         Anti-Submarine         Ships and their supporting platforms (e.g.,      MFH, MF1.............          1-2           11  Gulf Range Complex.
                             Warfare.               Warfare Mission        rotary-wing aircraft and unmanned aerial
                                                    Package Testing.       systems) detect, localize, and prosecute
                                                                           submarines.
Acoustic..................  Anti-Submarine         Anti-Submarine         Ships and their supporting platforms (e.g.,      MFH, MF1.............            2           14  Jacksonville Range
                             Warfare.               Warfare Mission        rotary-wing aircraft and unmanned aerial                                                          Complex.
                                                    Package Testing.       systems) detect, localize, and prosecute
                                                                           submarines.
Acoustic..................  Anti-Submarine         Anti-Submarine         Ships and their supporting platforms (e.g.,      MFH, MF1.............          1-2           11  Northeast Range
                             Warfare.               Warfare Mission        rotary-wing aircraft and unmanned aerial                                                          Complexes.
                                                    Package Testing.       systems) detect, localize, and prosecute
                                                                           submarines.
Acoustic..................  Anti-Submarine         At-Sea Sonar Testing.  At-sea testing to ensure systems are fully       MFL, MFM, MFH, MF1,            7-9           49  Gulf Range Complex;
                             Warfare.                                      functional in an open ocean environment.         MF1K, HFL, HFM, HFH,                             Jacksonville Range
                                                                                                                            Broadband (LF to                                 Complex; Navy
                                                                                                                            HF), Broadband (LF                               Cherry Point Range
                                                                                                                            to MF), Broadband                                Complex; Northeast
                                                                                                                            (MF to HF).                                      Range Complexes;
                                                                                                                                                                             SFOMF; Virginia
                                                                                                                                                                             Capes Range
                                                                                                                                                                             Complex.
Acoustic..................  Anti-Submarine         At-Sea Sonar Testing.  At-sea testing to ensure systems are fully       MFL, MFM, MFH, MF1,           7-14           77  Gulf Range Complex.
                             Warfare.                                      functional in an open ocean environment.         MF1K, HFL, HFM, HFH,
                                                                                                                            Broadband (LF to
                                                                                                                            HF), Broadband (LF
                                                                                                                            to MF), Broadband
                                                                                                                            (MF to HF).
Acoustic..................  Anti-Submarine         At-Sea Sonar Testing.  At-sea testing to ensure systems are fully       MFL, MFM, MFH, MF1,              4           28  Jacksonville Range
                             Warfare.                                      functional in an open ocean environment.         MF1K, HFL, HFM, HFH,                             Complex.
                                                                                                                            Broadband (LF to
                                                                                                                            HF), Broadband (LF
                                                                                                                            to MF), Broadband
                                                                                                                            (MF to HF).
Acoustic..................  Anti-Submarine         At-Sea Sonar Testing.  At-sea testing to ensure systems are fully       MFL, MFM, MFH, MF1,              2           14  Navy Cherry Point
                             Warfare.                                      functional in an open ocean environment.         MF1K, HFL, HFM, HFH,                             Range Complex.
                                                                                                                            Broadband (LF to
                                                                                                                            HF), Broadband (LF
                                                                                                                            to MF), Broadband
                                                                                                                            (MF to HF).
Acoustic..................  Anti-Submarine         At-Sea Sonar Testing.  At-sea testing to ensure systems are fully       MFL, MFM, MFH, MF1,           8-15           84  Northeast Range
                             Warfare.                                      functional in an open ocean environment.         MF1K, HFL, HFM, HFH,                             Complexes.
                                                                                                                            Broadband (LF to
                                                                                                                            HF), Broadband (LF
                                                                                                                            to MF), Broadband
                                                                                                                            (MF to HF).

[[Page 19881]]

 
Acoustic..................  Anti-Submarine         At-Sea Sonar Testing.  At-sea testing to ensure systems are fully       MFL, MFM, MFH, MF1,          16-22           58  Virginia Capes Range
                             Warfare.                                      functional in an open ocean environment.         MF1K, HFL, HFM, HFH,                             Complex.
                                                                                                                            Broadband (LF to
                                                                                                                            HF), Broadband (LF
                                                                                                                            to MF), Broadband
                                                                                                                            (MF to HF).
Acoustic..................  Anti-Submarine         At-Sea Sonar Testing.  At-sea testing to ensure systems are fully       MFL, MFM, MFH, MF1,              2           14  SFOMF.
                             Warfare.                                      functional in an open ocean environment.         MF1K, HFL, HFM, HFH,
                                                                                                                            Broadband (LF to
                                                                                                                            HF), Broadband (LF
                                                                                                                            to MF), Broadband
                                                                                                                            (MF to HF).
Acoustic..................  Anti-Submarine         Pierside Sonar         Pierside testing to ensure systems are fully     MFM, MFH, HFM, HFH,           5-10           64  NSB New London; Gulf
                             Warfare.               Testing.               functional in a controlled pierside              Broadband (MF to HF).                            Range Complex
                                                                           environment prior to at-sea test activities                                                       Inshore;
                                                                           and complete any required troubleshooting.                                                        Jacksonville Range
                                                                                                                                                                             Complex; NSB Kings
                                                                                                                                                                             Bay; Newport, RI;
                                                                                                                                                                             NS Norfolk;
                                                                                                                                                                             Northeast Range
                                                                                                                                                                             Complexes; Port
                                                                                                                                                                             Canaveral, FL;
                                                                                                                                                                             Virginia Capes
                                                                                                                                                                             Range Complex.
Acoustic..................  Anti-Submarine         Pierside Sonar         Pierside testing to ensure systems are fully     MFM, MFH, HFM, HFH,          10-20          110  Bath, ME.
                             Warfare.               Testing.               functional in a controlled pierside              Broadband (MF to HF).
                                                                           environment prior to at-sea test activities
                                                                           and complete any required troubleshooting.
Acoustic..................  Anti-Submarine         Pierside Sonar         Pierside testing to ensure systems are fully     MFM, MFH, HFM, HFH,          10-18           94  NS Mayport.
                             Warfare.               Testing.               functional in a controlled pierside              Broadband (MF to HF).
                                                                           environment prior to at-sea test activities
                                                                           and complete any required troubleshooting.
Acoustic..................  Anti-Submarine         Pierside Sonar         Pierside testing to ensure systems are fully     MFM, MFH, HFM, HFH,          63-84          455  NS Norfolk.
                             Warfare.               Testing.               functional in a controlled pierside              Broadband (MF to HF).
                                                                           environment prior to at-sea test activities
                                                                           and complete any required troubleshooting.
Acoustic..................  Anti-Submarine         Pierside Sonar         Pierside testing to ensure systems are fully     MFM, MFH, HFM, HFH,          10-20          110  Pascagoula, MS.
                             Warfare.               Testing.               functional in a controlled pierside              Broadband (MF to HF).
                                                                           environment prior to at-sea test activities
                                                                           and complete any required troubleshooting.
Acoustic..................  Anti-Submarine         Pierside Sonar         Pierside testing to ensure systems are fully     MFM, MFH, HFM, HFH,          16-24          152  Portsmouth Naval
                             Warfare.               Testing.               functional in a controlled pierside              Broadband (MF to HF).                            Shipyard.
                                                                           environment prior to at-sea test activities
                                                                           and complete any required troubleshooting.
Acoustic..................  Anti-Submarine         Surface Ship Sonar     Pierside and at-sea testing of ship systems      LFL, MFM, MF1, MF1K,             1            7  Jacksonville Range
                             Warfare.               Testing/Maintenance.   occurs periodically following major              Broadband (MF to HF).                            Complex.
                                                                           maintenance periods and for routine
                                                                           maintenance.
Acoustic..................  Anti-Submarine         Surface Ship Sonar     Pierside and at-sea testing of ship systems      LFL, MFM, MF1, MF1K,             4           28  Virginia Capes Range
                             Warfare.               Testing/Maintenance.   occurs periodically following major              Broadband (MF to HF).                            Complex.
                                                                           maintenance periods and for routine
                                                                           maintenance.
Acoustic and Explosive....  Anti-Submarine         Torpedo (Explosive)    Air, surface, or submarine crews employ          MFM, MFH, MF1, HFH,            1-5           17  Gulf Range Complex;
                             Warfare.               Testing.               explosive and non-explosive torpedoes against    Broadband (MF to                                 Jacksonville Range
                                                                           artificial targets.                              HF), E8, E11.                                    Complex; Key West
                                                                                                                                                                             Range Complex; Navy
                                                                                                                                                                             Cherry Point Range
                                                                                                                                                                             Complex; Northeast
                                                                                                                                                                             Range Complexes;
                                                                                                                                                                             Virginia Capes
                                                                                                                                                                             Range Complex.

[[Page 19882]]

 
Acoustic..................  Anti-Submarine         Torpedo (Non-          Air, surface, or submarine crews employ non-     MFL, MFM, MFH, MF1,          13-17           82  Gulf Range Complex;
                             Warfare.               Explosive) Testing.    explosive torpedoes against targets,             HFM, HFH, VHFH,                                  Jacksonville Range
                                                                           submarines, or surface vessels.                  Broadband (LF to                                 Complex; Key West
                                                                                                                            HF), Broadband (MF                               Range Complex; Navy
                                                                                                                            to HF).                                          Cherry Point Range
                                                                                                                                                                             Complex; Northeast
                                                                                                                                                                             Range Complexes;
                                                                                                                                                                             SFOMF; Virginia
                                                                                                                                                                             Capes Range
                                                                                                                                                                             Complex.
Acoustic..................  Anti-Submarine         Torpedo (Non-          Air, surface, or submarine crews employ non-     MFL, MFM, MFH, MF1,             30          210  NUWC Newport Testing
                             Warfare.               Explosive) Testing.    explosive torpedoes against targets,             HFM, HFH, VHFH,                                  Range.
                                                                           submarines, or surface vessels.                  Broadband (LF to
                                                                                                                            HF), Broadband (MF
                                                                                                                            to HF).
Explosive.................  Mine Warfare.........  Mine Countermeasure    Air, surface, and subsurface vessels neutralize  E4...................        18-45          315  Gulf Range Complex.
                                                    and Neutralization     threat mines and mine-like objects.
                                                    Testing.
Explosive.................  Mine Warfare.........  Mine Countermeasure    Air, surface, and subsurface vessels neutralize  E4...................      * 24-48        * 288  Virginia Capes Range
                                                    and Neutralization     threat mines and mine-like objects.                                                               Complex.
                                                    Testing.
Acoustic..................  Mine Warfare.........  Mine Countermeasure    Vessels and associated aircraft conduct mine     MFH, HFM, HFH........           15          105  Gulf Range Complex.
                                                    Mission Package        countermeasure operations.
                                                    Testing.
Acoustic..................  Mine Warfare.........  Mine Countermeasure    Vessels and associated aircraft conduct mine     MFH, HFM, HFH........            8           56  Jacksonville Range
                                                    Mission Package        countermeasure operations.                                                                        Complex.
                                                    Testing.
Acoustic..................  Mine Warfare.........  Mine Countermeasure    Vessels and associated aircraft conduct mine     MFH, HFM, HFH........           11           77  NSWC Panama City
                                                    Mission Package        countermeasure operations.                                                                        Testing Range.
                                                    Testing.
Acoustic..................  Mine Warfare.........  Mine Countermeasure    Vessels and associated aircraft conduct mine     MFH, HFM, HFH........            2           14  SFOMF.
                                                    Mission Package        countermeasure operations.
                                                    Testing.
Acoustic..................  Mine Warfare.........  Mine Countermeasure    Vessels and associated aircraft conduct mine     MFH, HFM, HFH........            3           21  Virginia Capes Range
                                                    Mission Package        countermeasure operations.                                                                        Complex.
                                                    Testing.
Acoustic..................  Mine Warfare.........  Mine Detection and     Air, surface, and subsurface vessels and         HFH..................          0-1            1  Jacksonville Range
                                                    Classification         systems detect and classify mines and mine-                                                       Complex, NSWC
                                                    Testing.               like objects. Vessels also assess their                                                           Panama City Testing
                                                                           potential susceptibility to mines and mine-                                                       Range, Port
                                                                           like objects.                                                                                     Canaveral, FL.
Acoustic..................  Mine Warfare.........  Mine Detection and     Air, surface, and subsurface vessels and         HFH..................          0-1            4  Jacksonville Range
                                                    Classification         systems detect and classify mines and mine-                                                       Complex.
                                                    Testing.               like objects. Vessels also assess their
                                                                           potential susceptibility to mines and mine-
                                                                           like objects.
Acoustic..................  Mine Warfare.........  Mine Detection and     Air, surface, and subsurface vessels and         HFH..................      286-287        2,005  NSWC Panama City
                                                    Classification         systems detect and classify mines and mine-                                                       Testing Range.
                                                    Testing.               like objects. Vessels also assess their
                                                                           potential susceptibility to mines and mine-
                                                                           like objects.
Acoustic and Explosive....  Acoustic and           Acoustic and           Research using active transmissions from         LFM, Broadband (LF to          0-1            1  Gulf Range Complex;
                             Oceanographic          Oceanographic          sources deployed from ships, aircraft, and       HF), E7.                                         Jacksonville Range
                             Science and            Research.              unmanned underwater vehicles. Research sources                                                    Complex; Key West
                             Technology.                                   can be used as proxies for current and future                                                     Range Complex.
                                                                           Navy systems.
Acoustic..................  Other Testing          Acoustic and           Research using active transmissions from         LFM, Broadband (LF to            3           21  Northeast Range
                             Activities.            Oceanographic          sources deployed from ships, aircraft, and       HF).                                             Complexes.
                                                    Research.              unmanned underwater vehicles. Research sources
                                                                           can be used as proxies for current and future
                                                                           Navy systems.
Acoustic and Explosive....  Other Testing          Acoustic and           Research using active transmissions from         LFM, Broadband (LF to        * 0-1          * 3  Key West Range
                             Activities.            Oceanographic          sources deployed from ships, aircraft, and       HF), E7.                                         Complex.
                                                    Research.              unmanned underwater vehicles. Research sources
                                                                           can be used as proxies for current and future
                                                                           Navy systems.

[[Page 19883]]

 
Acoustic..................  Other Testing          Acoustic and           Research using active transmissions from         LFM, Broadband (LF to          0-1            2  Other AFTT Areas.
                             Activities.            Oceanographic          sources deployed from ships, aircraft, and       HF).
                                                    Research.              unmanned underwater vehicles. Research sources
                                                                           can be used as proxies for current and future
                                                                           Navy systems.
Acoustic..................  Other Testing          Acoustic Component     Various surface vessels, moored equipment, and   LFL, MFL, MFH, HFM,             33          231  SFOMF.
                             Activities.            Testing.               materials are tested to evaluate performance     HFH, VHFH, Broadband
                                                                           in the marine environment.                       (LF to HF),
                                                                                                                            Broadband (MF to HF).
Acoustic..................  Other Testing          Acoustic Component     Various surface vessels, moored equipment, and   LFL, MFL, MFH, HFM,              1            7  Jacksonville Range
                             Activities.            Testing.               materials are tested to evaluate performance     HFH, VHFH, Broadband                             Complex.
                                                                           in the marine environment.                       (LF to HF),
                                                                                                                            Broadband (MF to HF).
Acoustic..................  Other Testing          Countermeasure         Countermeasure testing involves the testing of   MFM, MFH, HFH, VHFH,         16-20          116  Gulf Range Complex;
                             Activities.            Testing.               systems that will detect, localize, track, and   Broadband (LF to                                 Jacksonville Range
                                                                           engage incoming weapons, including marine        HF), Broadband (MF                               Complex; Key West
                                                                           vessel targets and airborne missiles. Testing    to HF).                                          Range Complex; Navy
                                                                           includes surface ship torpedo defense systems,                                                    Cherry Point Range
                                                                           marine vessel stopping payloads, and airborne                                                     Complex; Northeast
                                                                           decoys against air targets.                                                                       Range Complexes;
                                                                                                                                                                             Virginia Capes
                                                                                                                                                                             Range Complex; JEB
                                                                                                                                                                             Little Creek Fort
                                                                                                                                                                             Story.
Acoustic..................  Other Testing          Countermeasure         Countermeasure testing involves the testing of   MFM, MFH, HFH, VHFH,          8-10           63  Gulf Range Complex.
                             Activities.            Testing.               systems that will detect, localize, track, and   Broadband (LF to
                                                                           engage incoming weapons, including marine        HF), Broadband (MF
                                                                           vessel targets and airborne missiles. Testing    to HF).
                                                                           includes surface ship torpedo defense systems,
                                                                           marine vessel stopping payloads, and airborne
                                                                           decoys against air targets.
Acoustic..................  Other Testing          Countermeasure         Countermeasure testing involves the testing of   MFM, MFH, HFH, VHFH,             6           42  NUWC Newport Testing
                             Activities.            Testing.               systems that will detect, localize, track, and   Broadband (LF to                                 Range.
                                                                           engage incoming weapons, including marine        HF), Broadband (MF
                                                                           vessel targets and airborne missiles. Testing    to HF).
                                                                           includes surface ship torpedo defense systems,
                                                                           marine vessel stopping payloads, and airborne
                                                                           decoys against air targets.
Acoustic..................  Other Testing          Countermeasure         Countermeasure testing involves the testing of   MFM, MFH, HFH, VHFH,          6-10           13  Virginia Capes Range
                             Activities.            Testing.               systems that will detect, localize, track, and   Broadband (LF to                                 Complex.
                                                                           engage incoming weapons, including marine        HF), Broadband (MF
                                                                           vessel targets and airborne missiles. Testing    to HF).
                                                                           includes surface ship torpedo defense systems,
                                                                           marine vessel stopping payloads, and airborne
                                                                           decoys against air targets.
Acoustic..................  Other Testing          Insertion/Extraction.  Testing of submersibles capable of inserting     LFH, HFM, Broadband        501-502        3,514  Key West Range
                             Activities.                                   and extracting personnel and payloads into       (LF to MF).                                      Complex; NSWC
                                                                           denied areas from strategic distances.                                                            Panama City Testing
                                                                                                                                                                             Range.
Explosive.................  Other Testing          Line Charge Testing..  Surface vessels deploy line charges to test the  E4...................            4           28  NSWC Panama City
                             Activities.                                   capability to safely clear an area for                                                            Testing Range.
                                                                           expeditionary forces.
Acoustic and Explosive....  Other Testing          Semi-Stationary        Semi-stationary equipment (e.g., hydrophones)    AG230, HFH, HFM,            * 8-14         * 74  NSB New London;NS
                             Activities.            Equipment Testing.     is deployed to determine functionality.          Broadband (LF),                                  Mayport; NS
                                                                                                                            Broadband (LF to                                 Norfolk; Port
                                                                                                                            HF), Broadband (MF                               Canaveral, FL;
                                                                                                                            to HF), MFM, VHFH,                               Virginia Capes
                                                                                                                            VHFM, E4.                                        Range Complex
                                                                                                                                                                             Inshore; Key West
                                                                                                                                                                             Range Complex
                                                                                                                                                                             Inshore.

[[Page 19884]]

 
Acoustic and Explosive....  Other Testing          Semi-Stationary        Semi-stationary equipment (e.g., hydrophones)    AG230, HFH, HFM,                 4           28  Newport, RI.
                             Activities.            Equipment Testing.     is deployed to determine functionality.          Broadband (LF),
                                                                                                                            Broadband (LF to
                                                                                                                            HF), Broadband (MF
                                                                                                                            to HF), MFM, VHFH,
                                                                                                                            VHFM, E4.
Acoustic and Explosive....  Other Testing          Semi-Stationary        Semi-stationary equipment (e.g., hydrophones)    AG230, HFH, HFM,                30          210  NSWC Panama City
                             Activities.            Equipment Testing.     is deployed to determine functionality.          Broadband (LF),                                  Testing Range.
                                                                                                                            Broadband (LF to
                                                                                                                            HF), Broadband (MF
                                                                                                                            to HF), MFM, VHFH,
                                                                                                                            VHFM, E4.
Acoustic and Explosive....  Other Testing          Semi-Stationary        Semi-stationary equipment (e.g., hydrophones)    AG230, HFH, HFM,         * 155-173      * 1,139  NUWC Newport Testing
                             Activities.            Equipment Testing.     is deployed to determine functionality.          Broadband (LF),                                  Range.
                                                                                                                            Broadband (LF to
                                                                                                                            HF), Broadband (MF
                                                                                                                            to HF), MFM, VHFH,
                                                                                                                            VHFM, E4.
Acoustic..................  Other Testing          Towed Equipment        Surface vessels or unmanned surface vehicles     MFM, Broadband (LF)..        43-49          319  NUWC Newport Testing
                             Activities.            Testing.               deploy and tow equipment to determine                                                             Range.
                                                                           functionality of towed systems.
Explosive.................  Surface Warfare......  Gun Testing--Large-    Surface crews test large-caliber guns to defend  E3, E5...............       * 1-15         * 20  Jacksonville Range
                                                    Caliber.               against surface targets. Demonstration of                                                         Complex; Virginia
                                                                           large-caliber guns including the MK 45 5-inch                                                     Capes Range
                                                                           gun and MK 41 Vertical Launch Systems using                                                       Complex.
                                                                           surface to air missiles.
Explosive.................  Surface Warfare......  Gun Testing--Large-    Surface crews test large-caliber guns to defend  E3, E5...............          1-2           11  Gulf Range Complex.
                                                    Caliber.               against surface targets. Demonstration of
                                                                           large-caliber guns including the MK 45 5-inch
                                                                           gun and MK 41 Vertical Launch Systems using
                                                                           surface to air missiles.
Explosive.................  Surface Warfare......  Gun Testing--Large-    Surface crews test large-caliber guns to defend  E3, E5...............        * 2-4         * 23  Jacksonville Range
                                                    Caliber.               against surface targets. Demonstration of                                                         Complex.
                                                                           large-caliber guns including the MK 45 5-inch
                                                                           gun and MK 41 Vertical Launch Systems using
                                                                           surface to air missiles.
Explosive.................  Surface Warfare......  Gun Testing--Large-    Surface crews test large-caliber guns to defend  E3, E5...............          1-2           11  Northeast Range
                                                    Caliber.               against surface targets. Demonstration of                                                         Complexes.
                                                                           large-caliber guns including the MK 45 5-inch
                                                                           gun and MK 41 Vertical Launch Systems using
                                                                           surface to air missiles.
Explosive.................  Surface Warfare......  Gun Testing--Large-    Surface crews test large-caliber guns to defend  E3, E5...............         * 15        * 105  NSWC Panama City
                                                    Caliber.               against surface targets. Demonstration of                                                         Testing Range.
                                                                           large-caliber guns including the MK 45 5-inch
                                                                           gun and MK 41 Vertical Launch Systems using
                                                                           surface to air missiles.

[[Page 19885]]

 
Explosive.................  Surface Warfare......  Missile and Rocket     Missile and rocket testing includes various      E6, E7, E8, E10......       * 6-18         * 49  Gulf Range Complex;
                                                    Testing.               missiles or rockets fired from submarines and                                                     Jacksonville Range
                                                                           surface combatants. Testing of the launching                                                      Complex; Navy
                                                                           system and ship defense is performed.                                                             Cherry Point Range
                                                                                                                                                                             Complex; Virginia
                                                                                                                                                                             Capes Range
                                                                                                                                                                             Complex.
Explosive.................  Surface Warfare......  Missile and Rocket     Missile and rocket testing includes various      E6, E7, E8, E10......      * 20-30         * 78  Virginia Capes Range
                                                    Testing.               missiles or rockets fired from submarines and                                                     Complex.
                                                                           surface combatants. Testing of the launching
                                                                           system and ship defense is performed.
Acoustic..................  Unmanned Systems.....  Unmanned Underwater    Testing involves the production or upgrade of    LFL, MFL, MFM, MFH,        208-209        1,459  NSWC Panama City
                                                    Vehicle Testing.       unmanned underwater vehicles. This may include   HFM, HFH, VHFH,                                  Testing Range.
                                                                           testing of mine detection capabilities,          Broadband (LF to
                                                                           evaluating the basic functions of individual     HF), Broadband (MF
                                                                           platforms, or complex events with multiple       to HF).
                                                                           vehicles.
Acoustic..................  Unmanned Systems.....  Unmanned Underwater    Testing involves the production or upgrade of    LFL, MFL, MFM, MFH,            138          966  NUWC Newport Testing
                                                    Vehicle Testing.       unmanned underwater vehicles. This may include   HFM, HFH, VHFH,                                  Range.
                                                                           testing of mine detection capabilities,          Broadband (LF to
                                                                           evaluating the basic functions of individual     HF), Broadband (MF
                                                                           platforms, or complex events with multiple       to HF).
                                                                           vehicles.
Acoustic..................  Unmanned Systems.....  Unmanned Underwater    Testing involves the production or upgrade of    LFL, MFL, MFM, MFH,              1            7  SFOMF.
                                                    Vehicle Testing.       unmanned underwater vehicles. This may include   HFM, HFH, VHFH,
                                                                           testing of mine detection capabilities,          Broadband (LF to
                                                                           evaluating the basic functions of individual     HF), Broadband (MF
                                                                           platforms, or complex events with multiple       to HF).
                                                                           vehicles.
Acoustic..................  Vessel Evaluation....  In-Port Maintenance    Each combat system is tested to ensure they are  MF1..................            2            4  NS Mayport; NS
                                                    Testing.               functioning in a technically acceptable manner                                                    Norfolk.
                                                                           and are operationally ready to support at-sea
                                                                           testing.
Acoustic..................  Vessel Evaluation....  In-Port Maintenance    Each combat system is tested to ensure they are  MF1..................            2           14  NS Mayport.
                                                    Testing.               functioning in a technically acceptable manner
                                                                           and are operationally ready to support at-sea
                                                                           testing.
Acoustic..................  Vessel Evaluation....  In-Port Maintenance    Each combat system is tested to ensure they are  MF1..................            4           28  NS Norfolk.
                                                    Testing.               functioning in a technically acceptable manner
                                                                           and are operationally ready to support at-sea
                                                                           testing.
Acoustic..................  Vessel Evaluation....  Signature Analysis     Surface ship and submarine testing of            LFM, LFH, MFM, HFM,            0-1            4  Hampton Roads, VA.
                                                    Operations.            electromagnetic, acoustic, optical, and radar    Broadband (LF).
                                                                           signature measurements.
Acoustic..................  Vessel Evaluation....  Signature Analysis     Surface ship and submarine testing of            LFM, LFH, MFM, HFM,          79-94          579  SFOMF.
                                                    Operations.            electromagnetic, acoustic, optical, and radar    Broadband (LF).
                                                                           signature measurements.
Explosive.................  Vessel Evaluation....  Small Ship Shock       Underwater detonations are used to test new      E16..................          0-2            5  Jacksonville Range
                                                    Trial.                 ships or major upgrades.                                                                          Complex; Gulf Range
                                                                                                                                                                             Complex.
Acoustic..................  Vessel Evaluation....  Submarine Sea Trials-- Submarine weapons and sonar systems are tested   MFL, MFH, HFM, HFH,            3-7           22  Gulf Range Complex;
                                                    Weapons System         at-sea to meet the integrated combat system      Broadband (LF to HF).                            Jacksonville Range
                                                    Testing.               certification requirements.                                                                       Complex; NSB Kings
                                                                                                                                                                             Bay; Northeast
                                                                                                                                                                             Range Complexes;
                                                                                                                                                                             Port Canaveral, FL;
                                                                                                                                                                             Virginia Capes
                                                                                                                                                                             Range Complex.
Acoustic..................  Vessel Evaluation....  Submarine Sea Trials-- Submarine weapons and sonar systems are tested   MFL, MFH, HFM, HFH,            2-4           28  Northeast Range
                                                    Weapons System         at-sea to meet the integrated combat system      Broadband (LF to HF).                            Complexes.
                                                    Testing.               certification requirements.
Acoustic..................  Vessel Evaluation....  Submarine Sea Trials-- Submarine weapons and sonar systems are tested   MFL, MFH, HFM, HFH,              1            6  Northeast Range
                                                    Weapons System         at-sea to meet the integrated combat system      Broadband (LF to HF).                            Complexes Inshore.
                                                    Testing.               certification requirements.

[[Page 19886]]

 
Acoustic..................  Vessel Evaluation....  Submarine Sea Trials-- Submarine weapons and sonar systems are tested   MFL, MFH, HFM, HFH,            2-4           28  Virginia Capes Range
                                                    Weapons System         at-sea to meet the integrated combat system      Broadband (LF to HF).                            Complex.
                                                    Testing.               certification requirements.
Acoustic and Explosive....  Vessel Evaluation....  Surface Warfare        Tests the capabilities of shipboard sensors to   HFH, E3, E5, E6, E7,       * 17-76        * 206  Jacksonville Range
                                                    Testing.               detect, track, and engage surface targets.       E8.                                              Complex; Virginia
                                                                           Testing may include ships defending against                                                       Capes Range
                                                                           surface targets using explosive and non-                                                          Complex.
                                                                           explosive rounds, gun system structural test
                                                                           firing and demonstration of the response to
                                                                           Call for Fire against land-based targets
                                                                           (simulated by sea-based locations).
Acoustic..................  Vessel Evaluation....  Surface Warfare        Tests the capabilities of shipboard sensors to   HFH..................          0-2            6  Gulf Range Complex.
                                                    Testing.               detect, track, and engage surface targets.
                                                                           Testing may include ships defending against
                                                                           surface targets using non-explosive rounds,
                                                                           gun system structural test firing and
                                                                           demonstration of the response to Call for Fire
                                                                           against land-based targets (simulated by sea-
                                                                           based locations).
Acoustic and Explosive....  Vessel Evaluation....  Surface Warfare        Tests the capabilities of shipboard sensors to   HFH, E3, E5, E6, E7,         * 4-6         * 37  Jacksonville Range
                                                    Testing.               detect, track, and engage surface targets.       E8.                                              Complex.
                                                                           Testing may include ships defending against
                                                                           surface targets using explosive and non-
                                                                           explosive rounds, gun system structural test
                                                                           firing and demonstration of the response to
                                                                           Call for Fire against land-based targets
                                                                           (simulated by sea-based locations).
Acoustic and Explosive....  Vessel Evaluation....  Surface Warfare        Tests the capabilities of shipboard sensors to   HFH, E3, E5, E6, E7,         * 5-7         * 42  Virginia Capes Range
                                                    Testing.               detect, track, and engage surface targets.       E8.                                              Complex.
                                                                           Testing may include ships defending against
                                                                           surface targets using explosive and non-
                                                                           explosive rounds, gun system structural test
                                                                           firing and demonstration of the response to
                                                                           Call for Fire against land-based targets
                                                                           (simulated by sea-based locations).
Acoustic and Explosive....  Vessel Evaluation....  Undersea Warfare       Ships demonstrate capability of countermeasure   MFM, MFH, MF1, HFM,           6-24          105  Jacksonville Range
                                                    Testing.               systems and underwater surveillance, weapons     HFH, Broadband (LF                               Complex; Navy
                                                                           engagement and communications systems. This      to HF), E4.                                      Cherry Point Range
                                                                           tests ships ability to detect, track, and                                                         Complex; Northeast
                                                                           engage undersea targets.                                                                          Range Complexes;
                                                                                                                                                                             SFOMF; Virginia
                                                                                                                                                                             Capes Range
                                                                                                                                                                             Complex.
Acoustic and Explosive....  Vessel Evaluation....  Undersea Warfare       Ships demonstrate capability of countermeasure   MFM, MFH, MF1, HFM,          * 4-6         * 30  Jacksonville Range
                                                    Testing.               systems and underwater surveillance, weapons     HFH, Broadband (LF                               Complex.
                                                                           engagement and communications systems. This      to HF), E4.
                                                                           tests ships ability to detect, track, and
                                                                           engage undersea targets.
Acoustic..................  Vessel Evaluation....  Vessel Signature       Surface ship, submarine, and auxiliary system    MFM, HFM, HFH........          1-4            9  Jacksonville Range
                                                    Evaluation.            signature assessments. This may include                                                           Complex; Virginia
                                                                           electronic, radar, acoustic, infrared and                                                         Capes Range
                                                                           magnetic signatures.                                                                              Complex.
Acoustic..................  Vessel Evaluation....  Vessel Signature       Surface ship, submarine, and auxiliary system    MFM, HFM, HFH........          0-1            2  Gulf Range Complex.
                                                    Evaluation.            signature assessments. This may include
                                                                           electronic, radar, acoustic, infrared and
                                                                           magnetic signatures.
Acoustic..................  Vessel Evaluation....  Vessel Signature       Surface ship, submarine, and auxiliary system    MFM, HFM, HFH........          1-3            6  Hampton Roads, VA.
                                                    Evaluation.            signature assessments. This may include
                                                                           electronic, radar, acoustic, infrared and
                                                                           magnetic signatures.

[[Page 19887]]

 
Acoustic..................  Vessel Evaluation....  Vessel Signature       Surface ship, submarine, and auxiliary system    MFM, HFM, HFH........          0-1            3  NUWC Newport Testing
                                                    Evaluation.            signature assessments. This may include                                                           Range.
                                                                           electronic, radar, acoustic, infrared and
                                                                           magnetic signatures.
Acoustic..................  Vessel Evaluation....  Vessel Signature       Surface ship, submarine, and auxiliary system    MFM, HFM, HFH........          0-1            3  SFOMF.
                                                    Evaluation.            signature assessments. This may include
                                                                           electronic, radar, acoustic, infrared and
                                                                           magnetic signatures.
Acoustic..................  Vessel Evaluation....  Vessel Signature       Surface ship, submarine, and auxiliary system    MFM, HFM, HFH........          0-1            4  Virginia Capes Range
                                                    Evaluation.            signature assessments. This may include                                                           Complex.
                                                                           electronic, radar, acoustic, infrared and
                                                                           magnetic signatures.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: FL: Florida; GA: Georgia; JEB: Joint Expeditionary Base; LA: Louisiana; MS: Mississippi; NS: Naval Station; NSB: Naval Submarine Base; NSWC: Naval Surface Warfare Center; NUWC: Naval
  Undersea Warfare Center; RI: Rhode Island; SFOMF: South Florida Ocean Measurement Facility; VA: Virginia. The Gulf Range Complex and Gulf Range Complex Inshore includes geographically
  separated areas throughout the Gulf of America.
* Only a small subset of these activities include explosive ordnance.


[[Page 19888]]

    The ONR, as the Department of the Navy's science and technology 
provider, provides technology solutions for Navy and Marine Corps 
needs. The ONR's mission, defined by law, is to plan, foster, and 
encourage scientific research in recognition of its paramount 
importance as related to the maintenance of future naval power and the 
preservation of national security. The ONR manages the Navy's basic, 
applied, and advanced research to foster transition from science and 
technology to higher levels of research, development, test, and 
evaluation. The ONR is also a parent organization for the Naval 
Research Laboratory, which operates as the Navy's corporate research 
laboratory and conducts a broad multidisciplinary program of scientific 
research and advanced technological development. Testing activities 
conducted by the ONR and the Naval Research Laboratory include 
activities such as acoustic and oceanographic research, UUV research, 
and next generation mine countermeasures research. Table 9 summarizes 
the proposed testing activities for the ONR analyzed within the AFTT 
Study Area.

[[Page 19889]]



                                                          Table 9--Proposed ONR Testing Activities Analyzed Within the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                   Number of    Number of
     Stressor category          Activity type          Activity name                        Description                          Source bin        activities   activities        Location
                                                                                                                                                     1-year       7-year
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Acoustic and Explosive....  Acoustic and           Acoustic and           Research using active transmissions from         LFM, LFH, MFM, MFH,        * 12-15         * 93  Gulf Range Complex;
                             Oceanographic          Oceanographic          sources deployed from ships, aircraft, and       HFM, HFH, E1, E3,                                Jacksonville Range
                             Science and            Research.              unmanned vehicles. Research sources can be       3S3, AG232.                                      Complex; Northeast
                             Technology.                                   used as proxies for current and future Navy                                                       Range Complexes;
                                                                           systems.                                                                                          Virginia Capes
                                                                                                                                                                             Range Complex.
Acoustic..................  Acoustic and           Mine Countermeasure    Test involves the use of broadband acoustic      MFH..................          4-5           35  Gulf Range Complex;
                             Oceanographic          Technology Research.   sources on unmanned underwater vehicles.                                                          Jacksonville Range
                             Science and                                                                                                                                     Complex; Northeast
                             Technology.                                                                                                                                     Range Complexes;
                                                                                                                                                                             Virginia Capes
                                                                                                                                                                             Range Complex.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: The Gulf Range Complex includes geographically separated areas throughout the Gulf of America.
* Only a small subset of these activities include explosive ordnance.


[[Page 19890]]

Vessel Movement
    Vessels used as part of the proposed activities include both 
surface and sub-surface operations of both manned and unmanned vessels 
(USVs, UUVs). Navy vessels include ships, submarines, and boats ranging 
in size from small, 22 ft (7 m) rigid hull inflatable boats to aircraft 
carriers with lengths up to 1,092 ft (333 m). Unmanned systems may 
include vehicles ranging from 4-16 ft (1.2-4.9 m) but typical size of 
USVs is 36-328 ft (11-100 m), while UUVs are 33-98 ft (10-30 m) in 
length. The Marine Corps operates small boats from 10-50 ft (3-15.2 m) 
in length and include small unit riverine craft, rigid hull inflatable 
boats and amphibious combat vehicles. Coast Guard vessels range in size 
from small boats between 13 and 65 ft (3.9 to 19.8 m) to large cutters 
with lengths up to 418 ft (127.4 m).
    Large ships greater than 65 ft (19.8 m) generally operate at speeds 
in the range of 10 to 15 knots (kn; 18.5 to 27.8 km per hour (km/hr)) 
for fuel conservation. Submarines generally operate at lower speeds in 
transit and even lower speeds for certain tactical maneuvers. Small 
craft (considered in this proposed rule to be less than 60 ft (18 m) in 
length) have much more variable speeds (dependent on the mission). 
While these speeds are representative of most events, some vessels need 
to temporarily operate outside of these parameters. For example, to 
produce the required relative wind speed over the flight deck, an 
aircraft carrier vessel group engaged in flight operations must adjust 
its speed through the water accordingly. Conversely, there are other 
instances such as launch and recovery of a small rigid hull inflatable 
boat, vessel boarding, search and seizure training events, or retrieval 
of a target when vessels will be stopped or moving slowly ahead to 
maintain steerage. Additionally, there are specific events including 
high speed tests of newly constructed vessels. High speed ferries may 
also be used to support Navy testing in Narragansett Bay.
    The number of vessels used in the Study Area varies based on 
military readiness requirements, deployment schedules, annual budgets, 
and other unpredictable factors. Most military readiness activities 
involve the use of vessels. These activities could be widely dispersed 
throughout the Study Area, but would typically be conducted near naval 
ports, piers, and range areas. Activities involving vessel movements 
occur intermittently and are variable in duration, ranging from a few 
hours to multiple weeks.
    Action Proponent vessel traffic would be concentrated near Naval 
Station Norfolk in Norfolk, Virginia and Naval Station Mayport in 
Jacksonville, Florida. There is no seasonal differentiation in vessel 
use. Large vessel movement primarily occurs with the majority of the 
traffic flowing between the installations and the OPAREAs and/or 
testing and training ranges. Support craft would be more concentrated 
in the coastal waters in the areas of naval installations, ports, and 
ranges.
    The number of testing activities that include the use of vessels is 
around 12 percent lower than the number of training activities, but 
testing activities are more likely to include the use of larger 
unmanned vessels. In addition, testing often occurs jointly with a 
training event so it is likely that the testing activity would be 
conducted from a vessel that was also conducting a training activity. 
Vessel movement in conjunction with testing activities could occur 
throughout the Study Area, but would typically be conducted near naval 
ports, piers, and within range complexes.
    Additionally, a variety of smaller craft will be operated within 
the Study Area. Small craft types, sizes, and speeds vary. During 
military readiness activities, speeds generally range from 10 to 14 kn 
(18.5 to 25.9 km/hr); however, vessels can and will, on occasion, 
operate within the entire spectrum of their specific operational 
capabilities. In all cases, the vessels/craft will be operated in a 
safe manner consistent with the local conditions.
Foreign Navies
    Foreign militaries may participate in U.S. Navy training or testing 
activities in the AFTT Study Area. The Navy does not consider these 
foreign military activities as part of the ``specified activity'' under 
the MMPA, and NMFS defers to the applicant to describe the scope of its 
request for an authorization.
    The participation of foreign navies varies from year to year but 
overall is infrequent compared with Navy's total training and testing 
activities. When foreign militaries are participating in a U.S. Navy-
led exercise or event, foreign military use of sonar and explosives, 
when combined with the U.S. Navy's use of sonar and explosives, would 
not result in exceedance of the analyzed levels (within each Navy 
Acoustic Effects Model (NAEMO) modeled sonar and explosive bin) used 
for estimating predicted impacts, which formed the basis of our 
acoustic impacts effects analysis that was used to estimate take in 
this proposed rule. Please see the Proposed Mitigation Measures section 
and Proposed Reporting section of this proposed rule for information 
about mitigation and reporting related to foreign navy activities in 
the AFTT Study Area.
Standard Operating Procedures
    For training and testing to be effective, Action Proponent 
personnel must be able to safely use their sensors, platforms, weapons, 
and other devices to their optimum capabilities and as intended for use 
in missions and combat operations. The Action Proponents have developed 
standard operating procedures through decades of experience to provide 
for safety and mission success. Because they are essential to safety 
and mission success, standard operating procedures are part of the 
Proposed Action and are considered in the environmental analysis for 
applicable resources (see chapter 3 (Affected Environment and 
Environmental Consequences) of the 2024 AFTT Draft Supplemental EIS/
OEIS). Standard operating procedures recognized as providing a benefit 
to public safety or environmental resources are described in appendix A 
(Activity Descriptions) of the 2024 AFTT Draft Supplemental EIS/OEIS. 
While standard operating procedures are designed for the safety of 
personnel and equipment and to ensure the success of training and 
testing activities, their implementation often yields additional 
benefits on environmental, socioeconomic, public health and safety, and 
cultural resources.
    Because standard operating procedures are essential to safety and 
mission success, the Action Proponents consider them to be part of the 
proposed activities and have included them in the environmental 
analysis. Standard operating procedures that are recognized as 
providing a potential secondary benefit on marine mammals during 
training and testing activities are noted below.
    (i) Vessel safety;
    (ii) Weapons firing safety;
    (iii) Target deployment safety;
    (iv) Towed in-water device safety;
    (v) Pile driving safety; and
    (vi) Coastal zones.
    Standard operating procedures (which are implemented regardless of 
their secondary benefits) are different from mitigation measures (which 
are designed entirely for the purpose of avoiding or reducing impacts). 
Information on mitigation measures is provided in the Proposed 
Mitigation Measures section below. Additional information on standard 
operating procedures is discussed in more detail in appendix A 
(Activity Descriptions) of

[[Page 19891]]

the 2024 AFTT Draft Supplemental EIS/OEIS.

Description of Stressors

    The Action Proponents use a variety of sensors, platforms, weapons, 
and other devices, and military readiness activities using these 
systems may introduce sound and energy into the environment. The 
proposed military readiness activities were evaluated to identify 
specific components that would act as stressors by having direct or 
indirect impacts on marine mammals and their habitat. This analysis 
included identification of the spatial variation of the identified 
stressors. The following subsections describe the acoustic and 
explosive stressors for marine mammals and their habitat within the 
AFTT Study Area. Each description contains a list of activities that 
may generate the stressor. Stressor/resource interactions that were 
determined to have negligible (as defined for the purposes of the NEPA 
analyses) or impacts that do not rise to the level of take under the 
MMPA (i.e., vessel, aircraft, or weapons noise) were not carried 
forward for analysis in the application. NMFS reviewed the Action 
Proponents' analysis and conclusions on de minimis sources (i.e., those 
that are not likely to result in the take of marine mammals) and finds 
them complete and supportable (see section 3.7.4 of the technical 
report ``Quantifying Acoustic Impacts on Marine Mammals and Sea 
Turtles: Methods and Analytical Approach for Phase IV Training and 
Testing'' (U.S. Department of the Navy, 2024)).
Acoustic Stressors
    Acoustic stressors include acoustic signals emitted into the water 
for a specific purpose, such as sonar, other transducers (devices that 
convert energy from one form to another--in this case, into sound 
waves), and air guns, as well as incidental sources of broadband sound 
produced as a byproduct of vessel movement, aircraft transits, use of 
weapons or other deployed objects, vibratory pile extraction, and 
vibratory and impact pile driving. Explosives also produce broadband 
sound but are characterized separately from other acoustic sources due 
to their unique hazardous characteristics. Characteristics of each of 
these sound sources are described in the following sections.
    To better organize and facilitate the analysis of approximately 300 
sources of underwater sound used for training and testing by the Action 
Proponents, including sonars and other transducers, air guns, and 
explosives, a series of source classifications, or source bins, were 
used. The acoustic source classification bins do not include the 
broadband noise produced incidental to pile driving, vessel and 
aircraft transits, and weapons firing. Noise produced from vessel, 
aircraft, and weapons firing activities are not carried forward because 
those activities were found to have de minimis or no acoustic impacts, 
as stated above. Of note, the source bins used in this analysis have 
been revised from previous (Phase III) acoustic modeling to more 
efficiently group similar sources and use the parameters of the bin for 
propagation, making a comparison to previous bins impossible in most 
cases as some sources are modeled at different propagation parameters. 
For example, in previous analyses, non-impulsive narrowband sound 
sources were grouped into bins that were defined by their acoustic 
properties (i.e., frequency, source level, beam pattern, duty cycle) 
or, in some cases, their purpose or application. In the current 
analysis, these sources are binned based only on their acoustic 
properties and not on their purpose or application. As such, sources 
that previously fell into a single ``purpose-based'' bin now, in many 
cases, fall into multiple bins while sources with similar acoustic 
parameters that were previously sorted into separate bins due to 
different purposes now share a bin. Therefore, the acoustic source bins 
used in the current analysis do not represent a one-for-one replacement 
with previous bins, making direct comparison not possible in most 
cases.
    The use of source classification bins provides the following 
benefits:
    (i) Allows new sensors or munitions to be used under existing 
authorizations as long as those sources fall within the parameters of a 
``bin'';
    (ii) Improves efficiency of source utilization data collection and 
reporting requirements anticipated under the MMPA authorizations;
    (iii) Ensures that impacts are not underestimated, as all sources 
within a given class are modeled as the most impactful source (highest 
source level, longest duty cycle, or largest net explosive weight) 
within that bin;
    (iv) Allows analyses to be conducted in a more efficient manner, 
without any compromise of analytical results; and
    (v) Provides a framework to support the reallocation of source 
usage (hours/explosives) between different source bins, as long as the 
total numbers of takes remain within the overall analyzed and 
authorized limits. This flexibility is required to support evolving 
training and testing requirements, which are linked to real world 
events.
Sonar and Other Transducers--
    Active sonar and other transducers emit non-impulsive sound waves 
into the water to detect objects, navigate safely, and communicate. 
Passive sonars differ from active sound sources in that they do not 
emit acoustic signals; rather, they only receive acoustic information 
about the environment, or listen. In this proposed rule, the terms 
sonar and other transducers will be used to indicate active sound 
sources unless otherwise specified.
    The Action Proponents employ a variety of sonars and other 
transducers to obtain and transmit information about the undersea 
environment. Some examples are mid-frequency hull-mounted sonars used 
to find and track enemy submarines; high-frequency small object 
detection sonars used to detect mines; high-frequency underwater modems 
used to transfer data over short ranges; and extremely high-frequency 
(greater than 200 kilohertz (kHz)) Doppler sonars used for navigation, 
like those used on commercial and private vessels. The characteristics 
of these sonars and other transducers, such as source level (SL), beam 
width, directivity, and frequency, depend on the purpose of the source. 
Higher frequencies can carry more information or provide more 
information about objects off which they reflect, but attenuate more 
rapidly. Lower frequencies attenuate less rapidly, so they may detect 
objects over a longer distance, but with less detail.
    Propagation of sound produced underwater is highly dependent on 
environmental characteristics such as bathymetry, seafloor type, water 
depth, temperature, and salinity. The sound received at a particular 
location will be different than near the source due to the interaction 
of many factors, including propagation loss; how the sound is 
reflected, refracted, or scattered; the potential for reverberation; 
and interference due to multi-path propagation. In addition, absorption 
greatly affects the distance over which higher-frequency sounds 
propagate. The effects of these factors are explained in appendix D 
(Acoustic and Explosive Impacts Supporting Information) of the 2024 
AFTT Draft Supplemental EIS/OEIS. Because of the complexity of 
analyzing sound propagation in the ocean environment, the Action 
Proponents rely on acoustic models in their environmental analyses that 
consider sound source characteristics and varying ocean conditions 
across the AFTT Study Area. For additional information on how 
propagation is accounted for, see the technical report

[[Page 19892]]

``Quantifying Acoustic Impacts on Marine Mammals and Sea Turtles: 
Methods and Analytical Approach for Phase IV Training and Testing'' 
(U.S. Navy, 2024).
    The sound sources and platforms typically used in military 
readiness activities analyzed in the application are described in 
appendix A (Activity Descriptions) of the 2024 AFTT Draft Supplemental 
EIS/OEIS. Sonars and other transducers used to obtain and transmit 
information underwater during military readiness activities generally 
fall into several categories of use described below.
Anti-Submarine Warfare
    Sonar used during anti-submarine warfare training and testing would 
impart the greatest amount of acoustic energy of any category of sonar 
and other transducers analyzed in this proposed rule. Types of sonars 
used to detect potential enemy vessels include hull-mounted, towed, 
line array, sonobuoy, helicopter dipping, and torpedo sonars. In 
addition, acoustic targets and decoys (countermeasures) may be deployed 
to emulate the sound signatures of vessels or repeat received signals.
    Most anti-submarine warfare sonars are mid-frequency (1-10 kHz) 
because mid-frequency sound balances sufficient resolution to identify 
targets with distance over which threats can be identified. However, 
some sources may use higher or lower frequencies. Duty cycles can vary 
widely, from rarely used to continuously active. Anti-submarine warfare 
sonars can be wide-ranging in a search mode or highly directional in a 
track mode.
    Most anti-submarine warfare activities involving submarines or 
submarine targets would occur in waters greater than 600 ft (182.9 m) 
deep due to safety concerns about running aground at shallower depths. 
Sonars used for anti-submarine warfare activities would typically be 
used beyond 12 nmi (22.2 km) from shore. Exceptions include use of 
dipping sonar by helicopters, pierside testing and maintenance of 
systems while in port, and system checks while transiting to or from 
port.
Mine Warfare, Object Detection, and Imaging
    Sonars used to locate mines and other small objects, as well as 
those used in imaging (e.g., for hull inspections or imaging of the 
seafloor), are typically high-frequency or very high-frequency. Higher 
frequencies allow for greater resolution and, due to their greater 
attenuation, are most effective over shorter distances. Mine detection 
sonar can be deployed (towed or vessel hull-mounted) at variable depths 
on moving platforms (ships, helicopters, or unmanned vehicles) to sweep 
a suspected mined area. Hull-mounted anti-submarine sonars can also be 
used in an object detection mode known as ``Kingfisher'' mode. Sonars 
used for imaging are usually used in close proximity to the area of 
interest, such as pointing downward near the seafloor.
    Mine detection sonar use would be concentrated in areas where 
practice mines are deployed, typically in water depths less than 200 ft 
(60.9 m), and at established training or testing minefields or 
temporary minefields close to strategic ports and harbors. Kingfisher 
mode on vessels is most likely to be used when transiting to and from 
port. Sound sources used for imaging would be used throughout the AFTT 
Study Area.
Navigation and Safety
    Similar to commercial and private vessels, the Action Proponents' 
vessels employ navigational acoustic devices, including speed logs, 
Doppler sonars for ship positioning, and fathometers. These may be in 
use at any time for safe vessel operation. These sources are typically 
highly directional to obtain specific navigational data.
Communication
    Sound sources used to transmit data (such as underwater modems), 
provide location (pingers), or send a single brief release signal to 
seafloor-mounted devices (acoustic release) may be used throughout the 
AFTT Study Area. These sources typically have low duty cycles and are 
usually only used when it is necessary to send a detectable acoustic 
message.
Classification of Sonar and Other Transducers
    Sonars and other transducers are grouped into bins based on their 
acoustic properties. Sonars and other transducers are now grouped into 
bins based on the frequency or bandwidth, source level, duty-cycle, and 
three-dimensional beam coverage. Unless stated otherwise, a reference 
distance of decibel (dB) microPascal ([mu]Pa) at 1 m (3.3 ft) is used 
for sonar and other transducers.
    (i) Frequency of the non-impulsive acoustic source:
    a. Low-frequency sources operate below 1 kHz;
    b. Mid-frequency sources operate at or above 1 kHz, up to and 
including 10 kHz;
    c. High-frequency sources operate above 10 kHz, up to and including 
100 kHz; and
    d. Very high-frequency sources operate above 100 kHz but below 200 
kHz.
    (ii) Sound pressure level (SPL):
    a. Greater than 160 dB referenced to 1 microPascal (re 1 [mu]Pa), 
but less than 185 dB re 1 [mu]Pa;
    b. Equal to 185 dB re 1 [mu]Pa and up to 205 dB re 1 [mu]Pa; and
    c. Greater than 205 dB re 1 [mu]Pa.
    Active sonar and other transducer use that was quantitatively 
analyzed in the Study Area are shown in table 10.

                                                      Table 10--Sonar and Other Transducers Quantitatively Analyzed in the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                              Navy       Coast Guard   Coast Guard
             Source type                   Source category             Description             Unit        Navy training   training 7-    training     training 7-   Navy testing   Navy testing
                                                                                                              annual       year total      annual      year total       annual      7-year total
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Broadband............................  LF.....................  <205 dB.................  H                            -             -             -             -         206-252         1,580
Broadband............................  LF to MF...............  <205 dB.................  H                            -             -             -             -     1,501-1,503        10,519
Broadband............................  LF to HF...............  <205 dB.................  C                            -             -             -             -       791-1,020         5,101
Broadband............................  LF to HF...............  <205 dB.................  H                            -             -             -             -     2,367-2,571        16,356
Broadband............................  MF to HF...............  <205 dB.................  C                          133           931             -             -               -             -
Broadband............................  MF to HF...............  <205 dB.................  H                      935-951         6,595           280         1,960     2,749-2,950        19,308
Broadband............................  HF to VHF..............  <205 dB.................  H                           10            70             -             -               -             -
Low-frequency acoustic...............  LFL....................  160 dB to 185 dB........  H                            -             -             -             -           1,969        13,783
Low-frequency acoustic...............  LFM....................  185 dB to 205 dB........  C                            -             -             -             -             360         2,520
Low-frequency acoustic...............  LFM....................  185 dB to 205 dB........  H                          746         5,219             -             -     5,386-6,106        39,862
Low-frequency acoustic...............  LFH....................  >205 dB.................  C                  1,920-2,020        13,760             -             -     6,078-6,084        42,588

[[Page 19893]]

 
Low-frequency acoustic...............  LFH....................  >205 dB.................  H                          144         1,008             -             -         414-479         3,101
Mid-frequency acoustic...............  MFL....................  160 dB to 185 dB........  H                            -             -             -             -     3,238-3,582        22,336
Mid-frequency acoustic...............  MFM....................  185 dB to 205 dB........  C                  6,825-6,964        48,196             -             -   16,017-16,040       111,849
Mid-frequency acoustic...............  MFM....................  185 dB to 205 dB........  H                            2            14             -             -     3,081-3,509        23,012
Mid-frequency acoustic...............  MFH....................  >205 dB.................  H                  2,343-2,466        16,794             -             -     7,203-7,943        52,542
High-frequency acoustic..............  HFL....................  160 dB to 185 dB........  H                          169         1,183             -             -              96           672
High-frequency acoustic..............  HFM....................  185 dB to 205 dB........  C                            -             -             -             -       860-1,660         8,420
High-frequency acoustic..............  HFM....................  185 dB to 205 dB........  H                  1,253-1,255         8,777           210         1,470     4,125-4,489        29,941
High-frequency acoustic..............  HFH....................  >205 dB.................  C                          138           966             -             -     1,621-1,858        11,684
High-frequency acoustic..............  HFH....................  >205 dB.................  H                  3,892-3,940        27,436             -             -     3,779-4,580        28,383
Very high-frequency acoustic.........  VHFL...................  160 dB to 185 dB........  H                           12            84             -             -               -             -
Very high-frequency acoustic.........  VHFM...................  185 dB to 205 dB........  H                          918         6,426             -             -             120           840
Very high-frequency acoustic.........  VHFH...................  >205 dB.................  C                            -             -             -             -          69-103           520
Very high-frequency acoustic.........  VHFH...................  >205 dB.................  H                          579         4,051           140           980           5,584       -39,088
Hull-mounted surface ship sonar......  MF1C...................  Hull-mounted surface      H                      661-722         4,811             -             -           1,139         7,974
                                                                 ship sonar with duty
                                                                 cycle >80% (previously
                                                                 MF11).
Hull-mounted surface ship sonar......  MF1K...................  Hull-mounted surface      H                          280         1,957             -             -             108           759
                                                                 ship sonar in
                                                                 Kingfisher mode.
Hull-mounted surface ship sonar......  MF1....................  Hull-mounted surface      H                  3,498-3,870        25,602             -             -     1,102-1,390         8,464
                                                                 ship sonar.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: < = less than, C = count, dB = decibel, H = hours; - = not applicable.

Air Guns--
    Air guns are essentially stainless steel tubes charged with high-
pressure air via a compressor. An impulsive sound is generated when the 
air is almost instantaneously released into the surrounding water. 
Small air guns with capacities up to 60 cubic inches (in\3\) would be 
used during testing activities in various offshore areas in the AFTT 
Study Area.
    Generated impulses would have short durations, typically a few 
hundred milliseconds, with dominant frequencies below 1 kHz. The root-
mean-square (RMS) SPL and peak pressure (SPL peak) at a distance 1 m 
(3.3 ft) from the air gun would be approximately 215 dB re 1 [mu]Pa and 
227 dB re 1 [mu]Pa, respectively, if operated at the full capacity of 
60 in\3\. The size of the air gun chamber can be adjusted, which would 
result in lower SPLs and sound exposure level (SEL) per shot. The air 
gun and non-explosive impulsive sources that were quantitatively 
analyzed in the Study Area are shown in table 11.

  Table 11--Testing Air Gun and Non-Explosive Impulsive Sources Quantitatively Analyzed in the AFTT Study Area
----------------------------------------------------------------------------------------------------------------
     Source class category           Description        Unit         Testing annual        Testing 7-year total
----------------------------------------------------------------------------------------------------------------
NEI............................  Non-explosive       C                          192-240                    1,488
                                  impulsive.
AG.............................  Air gun...........  C                      4,400-5,400                   33,800
----------------------------------------------------------------------------------------------------------------
Note: C: count.

Pile Driving--
    Impact and vibratory pile driving and extraction would occur during 
Expeditionary Warfare, Port Damage Repair training in Gulfport, MS. The 
pile driving method, pile type and size, and assumptions for acoustic 
impact analysis are presented in table 12. This training activity would 
occur up to four times per year. Training events are typically 5 days 
each, for a total of 20 days per year. The training would involve the 
installation and extraction of 27-inch (0.69 m) steel sheets, 
installation of timber or plastic round 16-inch (0.41 m) piles using 
impact (impulsive) and vibratory (non-impulsive) methods, and the 
extraction of timber or plastic round 16-inch piles. When training 
events are complete, all piles and sheets are extracted using vibratory 
or dead pull methods. Crews would extract up to 12 piles in a 24-hour 
period.

[[Page 19894]]



                       Table 12--Port Damage Repair Training Piles Quantitatively Analyzed and Associated Underwater Sound Levels
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                       SEL  (single
                                                        Number of       Number of     Peak SPL  (dB  strike;  dB re 1   RMS SPL  (dB
             Method              Pile size and type   piles  annual   piles 7-year    re 1 [mu]Pa)        [mu]Pa2       re 1 [mu]Pa)       Reference
                                                                          total                         [middot]s)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Impact.........................  16-inch timber or               80             560             180               160             170  Caltrans (2020)--
                                  plastic round.                                                                                        Ballena Isle
                                                                                                                                        Marina.
Vibratory......................  16-inch timber or              160           1,120  ..............  ................             162  Caltrans (2020)--
                                  plastic round.                                                                                        Norfolk Naval
                                                                                                                                        Station.
Vibratory......................  27-inch steel                  240           1,680  ..............  ................             159  Naval Facilities
                                  sheet.                                                                                                Engineering
                                                                                                                                        Command
                                                                                                                                        Southwest
                                                                                                                                        (2020).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Impact method is for installation only.

    Only one hammer would be used at any given point in time; there 
would not be any instances where multiple piles would be driven 
simultaneously. All piles and sheets would be extracted using the 
vibratory hammer. Timber or plastic piles would also be extracted using 
a dead pull method.
    Impact pile driving would involve the use of an impact hammer with 
both it and the pile held in place by a crane. When the pile driving 
starts, the hammer part of the mechanism is raised up and allowed to 
fall, transferring energy to the top of the pile. The pile is thereby 
driven into the sediment by a repeated series of these hammer blows. 
Each blow results in an impulsive sound emanating from the length of 
the pile into the water column as well as from the bottom of the pile 
through the sediment. Broadband impulsive signals are produced by 
impact pile driving methods, with most of the acoustic energy 
concentrated below 1,000 hertz (Hz) (Hildebrand, 2009). For the 
purposes of this analysis, the Action Proponents assume the impact pile 
driver would generally operate on average 60 strikes per pile.
    Vibratory installation and extraction would involve the use of a 
vibratory hammer suspended from the crane and attached to the top of a 
pile. The pile is then vibrated by hydraulic motors rotating eccentric 
weights in the mechanism, causing a rapid up and down vibration in the 
pile, driving the pile into the sediment. During extraction, the 
vibration causes the sediment particles in contact with the pile to 
lose frictional grip on the pile. The crane slowly lifts the vibratory 
driver and pile until the pile is free of the sediment. In some cases, 
the crane may be able to lift the pile and vibratory driver without 
vibrations from the driver (dead pull), in which case no noise would be 
introduced into the water. Vibratory driving and extraction create 
broadband, continuous, non-impulsive noise at low source levels, for a 
short duration with most of the energy dominated by lower frequencies. 
Port Damage Repair training would occur in shallow water, and sound 
would be transmitted on direct paths through the water, be reflected at 
the water surface or bottom, or travel through seafloor substrate. Soft 
substrates such as sand would absorb or attenuate the sound more 
readily than hard substrates (rock), which may reflect the acoustic 
wave. The predicted sound levels produced by pile driving by method, 
pile size, and type for Port Damage Repair training are presented in 
table 12.
    In addition to underwater noise, the installation and extraction of 
piles also results in airborne noise in the environment, denoted dBA. 
dBA is an A-weighted decibel level that represents the relative 
loudness of sounds as perceived by the human ear. A-weighting gives 
more value to frequencies in the middle of human hearing and less value 
to frequencies at the edges as compared to a flat or unweighted decibel 
level. Impact pile driving creates in-air impulsive sound about 100 dBA 
re 20 [mu]Pa at a range of 15 m for 24-inch (0.61 m) steel piles 
(Illingworth and Rodkin, 2016). During vibratory extraction, the three 
aspects that generate airborne noise are the crane, the power plant, 
and the vibratory extractor. The average sound level recorded in air 
during vibratory extraction was about 85 dBA re 20 [mu]Pa (94 dB re 20 
[mu]Pa) within a range of 32.8-49.2 ft (10-15 m) (Illingworth and 
Rodkin, 2015).
Explosive Stressors
    This section describes the characteristics of explosions during 
military readiness activities. The activities analyzed in the 
application that use explosives are described in appendix A (Activity 
Descriptions) of the 2024 AFTT Draft Supplemental EIS/OEIS, and 
terminology and metrics used when describing explosives in the 
application are in appendix D (Acoustic and Explosive Impacts 
Supporting Information) of the 2024 AFTT Draft Supplemental EIS/OEIS.
    The near-instantaneous rise from ambient to an extremely high peak 
pressure is what makes an explosive shock wave potentially damaging. 
Farther from an explosive, the peak pressures decay and the explosive 
waves propagate as an impulsive, broadband sound. Several parameters 
influence the effect of an explosive: the weight of the explosive 
warhead, the type of explosive material, the boundaries and 
characteristics of the propagation medium, and the detonation depth in 
water. The net explosive weight (NEW), the explosive power of a charge 
expressed as the equivalent weight of trinitrotoluene (commonly 
referred to as TNT), accounts for the first two parameters.
Explosions in Water--
    Explosive detonations during military readiness activities are 
associated with high-explosive munitions, including, but not limited to 
bombs, missiles, rockets, naval gun shells, torpedoes, mines, 
demolition charges, and explosive sonobuoys. Explosive detonations 
during military readiness activities involving the use of high-
explosive munitions, including bombs, missiles, and naval gun shells, 
would occur in the air or near the water's surface. Explosive 
detonations associated with torpedoes and explosive sonobuoys would 
occur in the water column; mines and demolition charges would be 
detonated in the water column or on the ocean floor. The Coast Guard 
usage of explosives is limited to medium- and large-caliber munitions 
used during gunnery exercises. Most detonations would occur in waters 
greater than 200 ft (60.9 m) in depth and greater than 3 nmi (5.6 km) 
from shore, although mine warfare, demolition, and some testing 
detonations would occur in shallow water close to shore.
    To better organize and facilitate the analysis of explosives used 
by the Action Proponents during military readiness activities that 
would detonate in water or at the water surface, explosive 
classification bins were

[[Page 19895]]

developed. The use of explosive classification bins provides the same 
benefits as described for acoustic source classification bins in the 
Sonar and Other Transducers section. Explosives detonated in water are 
binned by NEW. Table 13 shows explosives use that was quantitatively 
analyzed in the Study Area. A range of annual use indicates that 
occurrence is anticipated to vary annually, consistent with the 
variation in the number of annual activities described in chapter 2 
(Description of Proposed Action and Alternatives) of the 2024 AFTT 
Draft Supplemental EIS/OEIS. The 7-year total takes that variability 
into account.

                         Table 13--Explosive Sources Quantitatively Analyzed Proposed for Use Underwater or at the Water Surface
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                            Coast Guard     Coast Guard
       Bin          Net  explosive    Example  explosive   Navy training   Navy training     training       training 7-    Navy testing    Navy testing
                        weight              source            annual          7-year          annual           year           annual          7-year
--------------------------------------------------------------------------------------------------------------------------------------------------------
E1...............          0.1-0.25  Medium-caliber                3,002          21,014               -               -           1,825          12,775
                                      projectile.
E2...............         >0.25-0.5  LAW rocket.........              60             420               -               -               -               -
E3...............          >0.5-2.5  2.75-inch rocket...           5,078          35,546             180           1,260     1,069-1,971           8,705
E4...............            >2.5-5  Mine neutralization              82             574               -               -     2,893-4,687          30,889
                                      charge.
E5...............             >5-10  Large-caliber                 1,109           7,763               -               -     1,268-1,860          11,540
                                      projectile.
E6...............            >10-20  Hellfire missile...             508           3,556               -               -           17-25             125
E7...............            >20-60  Demo block/shaped                10              70               -               -            8-22              62
                                      charge.
E8...............           >60-100  Maverick missile...              20             140               -               -           10-13              41
E9...............          >100-250  500 lb bomb........             138             966               -               -               5              35
E10..............          >250-500  Harpoon missile....              71             497               -               -               4              28
E11..............          >500-675  Torpedo............               1               7               -               -             1-2               8
E12..............        >675-1,000  2,000 lb bomb......              20             140               -               -               -               -
E16..............     >7,250-14,500  Small ship shock                  -               -               -               -             0-6              15
                                      trial.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: > = greater than, lb = pound, - = not applicable.

    Propagation of explosive pressure waves in water is highly 
dependent on environmental characteristics such as bathymetry, seafloor 
type, water depth, temperature, and salinity, which affect how the 
pressure waves are reflected, refracted, or scattered; the potential 
for reverberation; and interference due to multi-path propagation. In 
addition, absorption greatly affects the distance over which higher-
frequency components of explosive broadband noise can propagate. 
Appendix D (Acoustic and Explosive Impacts Supporting Information) of 
the 2024 AFTT Draft Supplemental EIS/OEIS explains the characteristics 
of explosive detonations and how the above factors affect the 
propagation of explosive energy in the water. Because of the complexity 
of analyzing sound propagation in the ocean environment, the Action 
Proponents rely on acoustic models in their environmental analyses that 
consider sound source characteristics and varying ocean conditions 
across the Study Area.
Vessel Strike
    NMFS also considered the likelihood that vessel movement during 
military readiness activities could result in an incidental, but 
intentional, strike of a marine mammal in the AFTT Study Area, which 
has the potential to result in serious injury or mortality. Vessel 
strikes are not specific to any specific military readiness activity 
but rather, a limited, sporadic, and incidental result of the Action 
Proponents' vessel movement during military readiness activities within 
the Study Area. Vessel strikes from commercial, recreational, and 
military vessels are known to seriously injure and occasionally kill 
cetaceans (Abramson et al., 2011; Berman-Kowalewski et al., 2010; 
Calambokidis, 2012, Crum et al., 2019, Douglas et al., 2008, Laggner, 
2009, Lammers et al., 2003, Van der Hoop et al., 2012, Van der Hoop et 
al., 2013), although reviews of the literature on vessel strikes mainly 
involve collisions between commercial vessels and whales (Jensen and 
Silber, 2003, Laist et al., 2001). Vessel speed, size, and mass are all 
important factors in determining both the potential likelihood and 
impacts of a vessel strike to marine mammals (Blondin et al., 2025; 
Conn and Silber, 2013; Garrison et al., 2025; Gende et al., 2011; 
Redfern et al., 2019; Silber et al., 2010; Szesciorka et al., 2019; 
Vanderlaan and Taggart, 2007; Wiley et al., 2016). For large vessels, 
speed and angle of approach can influence the severity of a strike.
    The Action Proponents' vessels transit at speeds that are optimal 
for fuel conservation or to meet training and testing requirements. 
From unpublished Navy data, average median speed for large Navy ships 
in the other Navy ranges from 2011-2015 varied from 10 to 15 kn (18.5 
to 27.8 km/hr) depending on ship class and geographic location (i.e., 
slower speeds close to the coast). Similar patterns are anticipated in 
the AFTT Study Area. A full description of the Action Proponents' 
vessels proposed for use during military readiness activities can be 
found in chapter 2 (Description of Proposed Action and Alternatives) of 
the 2024 AFTT Draft Supplemental EIS/OEIS.
    While these speeds for large Navy vessels are representative of 
most events, some of the Action Proponents' vessels may need to 
temporarily operate outside of these parameters. For example, to 
produce the required relative wind speed over the flight deck, an 
aircraft carrier engaged in flight operations must adjust its speed 
through the water accordingly. There are a few specific events, 
including high speed tests of newly constructed vessels, where the 
Action Proponents' vessel would operate at higher speeds. High speed 
ferries may also be used to support Navy testing in Narragansett Bay. 
By comparison, there are other instances when the Action Proponents 
vessel would be stopped or moving slowly ahead to maintain steerage, 
such as launch and recovery of a small rigid hull inflatable boat; 
vessel boarding, search, and seizure training events; or retrieval of a 
target.
    Large Navy vessels (greater than 65 ft (19.8 m)) and Coast Guard 
vessels within the offshore areas of range complexes and testing ranges 
operate differently from commercial vessels, which may reduce potential 
vessel strikes of large whales. Surface ships operated by or for the 
Navy have multiple personnel assigned to stand watch at all times, when 
a ship or surfaced submarine is moving through the water (underway). A 
primary duty of personnel standing watch on surface ships is to detect 
and report all objects and disturbances sighted in the water that may 
indicate a threat to the vessel

[[Page 19896]]

and its crew, such as debris, a periscope, surfaced submarine, or 
surface disturbance. Per vessel safety requirements, personnel standing 
watch also report any marine mammals sighted in the path of the vessel 
as a standard collision avoidance procedure. All vessels proceed at a 
safe speed so they can take proper and effective action to avoid a 
collision with any sighted object or disturbance and can stop within a 
distance appropriate to the prevailing circumstances and conditions. As 
described in the Standard Operating Procedures section, the Action 
Proponents utilize Lookouts to avoid collisions, and Lookouts are 
trained to spot marine mammals so that vessels may change course or 
take other appropriate action to avoid collisions. Despite the 
precautions, should a vessel strike occur, NMFS anticipates that it 
would likely result in incidental take in the form of serious injury 
and/or mortality, though it is possible that it could result in non-
serious injury (Level A harassment). Accordingly, for the purposes of 
this analysis, NMFS assumes that any vessel strike would result in 
serious injury or mortality.
    Proposed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Proposed 
Mitigation Measures section, Proposed Monitoring section, and Proposed 
Reporting section).

Description of Marine Mammals in the Area of Specified Activities

    Marine mammal species and their associated stocks that have the 
potential to occur in the AFTT Study Area are presented in table 14 
along with each stock's Endangered Species Act (ESA) and MMPA statuses, 
abundance estimate and associated coefficient of variation (CV) value, 
minimum abundance estimate, potential biological removal (PBR), annual 
M/SI, and potential occurrence in the AFTT Study Area. The Action 
Proponents request authorization to take individuals of 41 species (81 
stocks) by Level A and Level B harassment incidental to military 
readiness activities from the use of sonar and other transducers, in-
water detonations, air guns, pile driving/extraction, and vessel 
movement in the AFTT Study Area. Of note, the 2019 AFTT Final Rule (84 
FR 70712, December 23, 2019) refers to the Northern Gulf of America 
stock of Bryde's whales (Balaenoptera edeni). These whales were 
subsequently described as a new species, Rice's whale (Balaenoptera 
ricei) (Rosel et al., 2021), and NMFS refers to them as Rice's whale 
throughout this rulemaking. Currently, the North Atlantic right whale 
(NARW; Eubalaena glacialis) has critical habitat designated under the 
ESA in the AFTT Study Area, and the Rice's whale has proposed ESA-
designated critical habitat in the AFTT Study Area (see Critical 
Habitat section below).
    Sections 3 and 4 of the application summarize available information 
regarding status and trends, distribution and habitat preferences, and 
behavior and life history of the potentially affected species. NMFS 
fully considered all of this information, and we refer the reader to 
these descriptions, instead of reprinting the information. Additional 
information regarding population trends and threats may be found in 
NMFS' Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments), and 
more general information about these species (e.g., physical and 
behavioral descriptions) may be found on NMFS' website (https://www.fisheries.noaa.gov/find-species). Additional information on the 
general biology and ecology of marine mammals is included in the 2024 
AFTT Draft Supplemental EIS/OEIS.
    Table 14 incorporates the best available science, including data 
from the U.S. Atlantic and Gulf of Mexico Marine Mammal Stock 
Assessment Report (Hayes et al., 2024) (now referred to as the Gulf of 
America; see https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments), and 2024 draft SAR, as 
well as monitoring data from the Navy's marine mammal research efforts 
(note, the application includes information from the 2022 final SAR but 
does not include information from the 2023 final SAR and 2024 draft SAR 
as they were not available at the time of application submission).

[[Page 19897]]



                                                                  Table 14--Marine Mammal Occurrence in the AFTT Study Area \1\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                             Stock  abundance
                                                                               ESA/ MMPA      (CV, Nmin, most                                                Occurrence in    Occurrence in port
           Common name              Scientific name           Stock             status;      recent  abundance     PBR     Annual M/     Occurrence in        associated         and  pierside
                                                                            strategic  (Y/      survey) \3\                  SI \4\     range complexes     inshore waters         locations
                                                                                N) \2\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                     Order Artiodactyla--Cetacea--Mysticeti (baleen whales)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Family Balaenidae:
    North Atlantic Right Whale    Eubalaena glacialis  Western............  E, D, Y         372 (0, 367, 2023)       0.73       14.8  Northeast RC, NUWC  Northeast RC        Civilian Ports:
     \5\.                                                                                                                              Division Newport    Inshore,            Boston, MA,
                                                                                                                                       Testing Range,      Jacksonville RC     Earle, NJ,
                                                                                                                                       VACAPES RC, Navy    Inshore.            Delaware Bay, DE,
                                                                                                                                       Cherry Point RC,                        Hampton Roads,
                                                                                                                                       JAX RC, SFOMF,                          VA, Morehead
                                                                                                                                       Key West RC                             City, NC,
                                                                                                                                       (extralimital),                         Wilmington, NC,
                                                                                                                                       NSWC Panama City                        Kings Bay, GA,
                                                                                                                                       Division Testing                        Savannah, GA,
                                                                                                                                       Range                                   Mayport, FL, Port
                                                                                                                                       (extralimital),                         Canaveral, FL
                                                                                                                                       Gulf RC                                 (extralimital);
                                                                                                                                       (extralimital),                         Coast Guard
                                                                                                                                       SINKEX Box, Other                       Stations: Boston,
                                                                                                                                       AFTT Areas.                             MA, Virginia
                                                                                                                                                                               Beach, VA,
                                                                                                                                                                               Charleston, SC,
                                                                                                                                                                               Mayport, FL, Cape
                                                                                                                                                                               Canaveral, FL
                                                                                                                                                                               (extralimital).
Family Balaenopteridae
 (rorquals):
    Blue Whale..................  Balaenoptera         Western North        E, D, Y         UNK (UNK, 402, See        0.8          0  Northeast RC, NUWC  N/A...............  N/A.
                                   musculus.            Atlantic.                            SAR) \6\.                                 Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SINKEX
                                                                                                                                       Box, Other AFTT
                                                                                                                                       Areas.
    Bryde's Whale...............  Balaenoptera edeni.  Primary............  (7 8)           ..................  .........  .........  Other AFTT Areas..  N/A...............  N/A.
    Fin Whale...................  Balaenoptera         Western North        E, D, Y         6,802 (0.24,               11       2.05  Northeast RC,
                                   physalus.            Atlantic.                            5,573, 2021).                             VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, Key West
                                                                                                                                       RC, Gulf RC
                                                                                                                                       (extralimital),
                                                                                                                                       NSWC Panama City
                                                                                                                                       Testing Range
                                                                                                                                       (extralimital),
                                                                                                                                       SINKEX Box, Other
                                                                                                                                       AFTT Areas.
    Fin Whale...................  Balaenoptera         Gulf of St.          ..............  ..................  .........  .........  Other AFTT Areas..
                                   physalus.            Lawrence.
    Fin Whale...................  Balaenoptera         West Greenland.....  ..............  ..................  .........  .........  Other AFTT Areas..
                                   physalus.
    Humpback Whale..............  Megaptera            Gulf of Maine......  -, -, N         1,396 (0, 1380,            22      12.15  Northeast RC, NUWC  Northeast RC        Civilian Ports:
                                   novaeangliae.                                             2016).                                    Division, Newport   Inshore, VACAPES    Boston, MA,
                                                                                                                                       Testing Range,      Inshore,            Earle, NJ,
                                                                                                                                       VACAPES RC, Navy    Jacksonville RC     Delaware Bay, DE,
                                                                                                                                       Cherry Point RC,    Inshore.            Hampton Roads,
                                                                                                                                       JAX RC, SFOMF,                          VA, Morehead
                                                                                                                                       Key West RC, NSWC                       City, NC,
                                                                                                                                       Panama City                             Wilmington, NC;
                                                                                                                                       Division Testing                        Coast Guard
                                                                                                                                       Range, Gulf RC,                         Stations: Boston,
                                                                                                                                       SINKEX Box, Other                       MA, Newport, RI,
                                                                                                                                       AFTT Areas.                             Virginia Beach,
                                                                                                                                                                               VA, Charleston,
                                                                                                                                                                               SC, Mayport, FL,
                                                                                                                                                                               Cape Canaveral,
                                                                                                                                                                               FL, Fort Pierce,
                                                                                                                                                                               FL, Dania, FL,
                                                                                                                                                                               Miami, FL, Key
                                                                                                                                                                               West, FL, St.
                                                                                                                                                                               Petersburg, FL,
                                                                                                                                                                               Pensacola, FL,
                                                                                                                                                                               New Orleans, LA,
                                                                                                                                                                               Corpus Christi,
                                                                                                                                                                               TX.

[[Page 19898]]

 
    Minke Whale.................  Balaenoptera         Canadian East Coast  -, -, N         21,968 (0.31,             170        9.4  Northeast RC, NUWC  Northeast RC        Civilian Ports:
                                   acutorostrata.                                            17,002, 2021).                            Division Newport    Inshore, VACAPES    Boston, MA,
                                                                                                                                       Testing Range,      Inshore,            Earle, NJ,
                                                                                                                                       VACAPES RC, Navy    Jacksonville RC     Delaware Bay, DE,
                                                                                                                                       Cherry Point RC,    Inshore.            Hampton Roads,
                                                                                                                                       JAX RC, SFOMF,                          VA, Morehead
                                                                                                                                       Key West RC, NSWC                       City, NC,
                                                                                                                                       Panama City                             Wilmington, NC,
                                                                                                                                       Division Testing                        Kings Bay, GA,
                                                                                                                                       Range, Gulf RC,                         Savannah, GA;
                                                                                                                                       SINKEX Box, Other                       Coast Guard
                                                                                                                                       AFTT Areas.                             Stations: Boston,
                                                                                                                                                                               MA, Newport, RI,
                                                                                                                                                                               Virginia Beach,
                                                                                                                                                                               VA, Charleston,
                                                                                                                                                                               SC, Mayport, FL,
                                                                                                                                                                               Cape Canaveral,
                                                                                                                                                                               FL, Fort Pierce,
                                                                                                                                                                               FL, Dania, FL,
                                                                                                                                                                               Miami, FL, Key
                                                                                                                                                                               West, FL, St.
                                                                                                                                                                               Petersburg, FL,
                                                                                                                                                                               Pensacola, FL,
                                                                                                                                                                               New Orleans, LA,
                                                                                                                                                                               Corpus Christi,
                                                                                                                                                                               TX.
    Minke Whale.................  Balaenoptera         West Greenland.....  (\9\)           ..................  .........  .........  Other AFTT Areas..
                                   acutorostrata.
    Rice's Whale................  Balaenoptera ricei.  Northern Gulf of     E, -, Y         51 (0.5, 34, 2018)        0.1   \10\ 0.5  Gulf RC, Key West   Gulf RC Inshore...  Civilian Ports:
                                                        America.                                                                       RC, NSWC Panama                         Tampa, FL,
                                                                                                                                       City Testing                            Beaumont, TX,
                                                                                                                                       Range.                                  Corpus Christi,
                                                                                                                                                                               TX.
    Sei Whale...................  Balaenoptera         Nova Scotia........  E, D, Y         6,292 (1.02,              6.2        0.6  Northeast RC, NUWC  N/A...............  N/A.
                                   borealis.                                                 3,098, 2021).                             Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, Gulf RC,
                                                                                                                                       SINKEX Box, Other
                                                                                                                                       AFTT Areas.
    Sei Whale...................  Balaenoptera         Labrador Sea.......  (\11\)          ..................  .........  .........  Other AFTT Areas..
                                   borealis.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      Odontoceti (toothed whales, dolphins, and porpoises)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Family Physeteridae:
    Sperm Whale.................  Physeter             North Atlantic.....  E, D, Y         5,895 (0.29,             9.28        0.2  Northeast RC, NUWC  N/A...............  N/A.
                                   macrocephalus.                                            4,639, 2021).                             Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, Gulf RC,
                                                                                                                                       SINKEX Box, Other
                                                                                                                                       AFTT Areas.
    Sperm Whale.................  Physeter             Northern Gulf of     E, D, Y         1,180 (0.22, 983,           2        9.6  Gulf, NSWC Panama   N/A...............  N/A.
                                   macrocephalus.       America.                             2018).                                    City Testing
                                                                                                                                       Range.
    Sperm Whale.................  Physeter             Puerto Rico and      E, D, Y         UNK (UNK, UNK, See        UNK        UNK  Other AFTT Areas..  N/A...............  N/A.
                                   macrocephalus.       U.S. Virgin                          SAR).
                                                        Islands.
Family Kogiidae:
    Dwarf Sperm Whale...........  Kogia sima.........  Northern Gulf of     -, -, N         336 (0.35, 253,           2.5         31  Gulf RC...........  N/A...............  N/A.
                                                        America \12\.                        2018).
    Dwarf Sperm Whale...........  Kogia sima.........  Western North        -, -, N         9,474 (0.36,               57        UNK  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic \13\.                       7,080, 2021).                             Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Pygmy Sperm Whale...........  Kogia breviceps....  Northern Gulf of     -, -, N         336 (0.35, 253,           2.5         31  Gulf RC...........  N/A...............  N/A.
                                                        America \12\.                        2018).

[[Page 19899]]

 
    Pygmy Sperm Whale...........  Kogia breviceps....  Western North        -, -, N         9,474 (0.36,               57        UNK  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic \13\.                       7,080, 2021).                             Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
Family Ziphiidae (beaked
 whales):
    Blainville's Beaked Whale...  Mesoplodon           Northern Gulf of     -, -, N         98 (0.46, 68,             0.7        5.2  Gulf RC...........  N/A...............  N/A.
                                   densirostris.        America.                             2018).
    Blainville's Beaked Whale...  Mesoplodon           Western North        -, -, N         2,936 (0.26,               24          0  Northeast RC, NUWC  N/A...............  N/A.
                                   densirostris.        Atlantic \14\.                       2,374, 2021).                             Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Goose-Beaked Whale..........  Ziphius cavirostris  Northern Gulf of     -, -, N         18 (0.75, 10,             0.1        5.2  Gulf RC...........  N/A...............  N/A.
                                                        America.                             2018).
    Goose-Beaked Whale..........  Ziphius cavirostris  Puerto Rico and      -, -, Y         UNK (UNK, UNK, N/         UNK        UNK  Other AFTT Areas..  N/A...............  N/A.
                                                        U.S. Virgin                          A).
                                                        Islands.
    Goose-Beaked Whale..........  Ziphius cavirostris  Western North        -, -, N         4,260 (0.24,               38        0.2  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            3,817, 2021).                             Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Other AFTT Areas.
    Gervais' Beaked Whale.......  Mesoplodon           Northern Gulf of     -, -, N         20 (0.98, 10,             0.1        5.2  Gulf RC...........  N/A...............  N/A.
                                   europaeus.           America.                             2018).
    Gervais' Beaked Whale.......  Mesoplodon           Western North        -, -, N         8,595 (0.24,               70          0  Northeast RC, NUWC  N/A...............  N/A.
                                   europaeus.           Atlantic \15\.                       7,022, 2021).                             Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Northern Bottlenose Whale...  Hyperoodon           Western North        -, -, N         UNK (UNK, UNK,            UNK          0  Other AFTT Areas..  N/A...............  N/A.
                                   ampullatus.          Atlantic.                            2016).
    Sowerby's Beaked Whale......  Mesoplodon bidens..  Western North        -, -, N         492 (0.50, 340,           3.4          0  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            2021).                                    Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    True's Beaked Whale.........  Mesoplodon mirus...  Western North        -, -, N         4,480 (0.34,               34        0.2  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            3,391, 2021).                             Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, Gulf RC,
                                                                                                                                       Other AFTT Areas.
Family Delphinidae:
    Atlantic Spotted Dolphin....  Stenella frontalis.  Northern Gulf of     -, -, N         21,506 (0.26,             166         36  Gulf RC, Other      N/A...............  N/A.
                                                        America.                             17,339, 2018).                            AFTT Areas.
    Atlantic Spotted Dolphin....  Stenella frontalis.  Puerto Rico and      -, -, Y         UNK (UNK, UNK, N/         UNK        UNK  Other AFTT Areas..  N/A...............  N/A.
                                                        U.S. Virgin                          A).
                                                        Islands.
    Atlantic Spotted Dolphin....  Stenella frontalis.  Western North        -, -, N         31,506 (0.28,             250          0  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            25,042, 2021).                            Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Atlantic White-Sided Dolphin  Lagenorhynchus       Western North        -, -, N         93,233 (0.71,             544         28  Northeast RC,       N/A...............  Civilian Ports:
                                   acutus.              Atlantic.                            54,443, 2021).                            VACAPES RC, Other                       Boston, MA; Coast
                                                                                                                                       AFTT Areas.                             Guard Stations:
                                                                                                                                                                               Boston, MA.
    Bottlenose Dolphin..........  Tursiops truncatus.  Biscayne Bay.......  -, -, N         241 (0.04, 233,           2.3          1  Other AFTT Areas..  N/A...............  N/A.
                                                                                             2019).

[[Page 19900]]

 
    Tamanend's bottlenose         Tursiops erebennus.  Western North        -, -, Y         2,541 (0.46,               18        0.2  JAX RC............  JAX RC Inshore....  Civilian Ports:
     dolphin.                                           Atlantic, Central                    1,760, 2021).                                                                     Port Canaveral,
                                                        Florida Coastal.                                                                                                       FL.
    Bottlenose Dolphin..........  Tursiops truncatus.  Central GA           -, -, N         UNK (UNK, UNK,            UND        0.4  Other AFTT Areas..  N/A...............  N/A.
                                                        Estuarine.                           2008-2009).
    Bottlenose Dolphin..........  Tursiops truncatus.  Charleston           -, -, Y         UNK (UNK, UNK,            UND        2.2  Other AFTT Areas..  JAX RC Inshore....  N/A.
                                                        Estuarine.                           2005-2006).
    Bottlenose Dolphin..........  Tursiops truncatus.  Gulf of America      Y               ..................  .........  .........  Gulf RC...........  Gulf RC Inshore...  N/A.
                                                        Bay, Sound, and
                                                        Estuaries \16\.
    Bottlenose Dolphin..........  Tursiops truncatus.  Gulf of America      -, -, N         16,407 (0.17,             114        9.2  Gulf RC...........  Gulf RC Inshore...  N/A.
                                                        Eastern Coastal.                     14,199, 2018).
    Bottlenose Dolphin..........  Tursiops truncatus.  Gulf of America      -, -, N         11,543 (0.19,              89         28  Gulf RC...........  Gulf RC Inshore...  N/A.
                                                        Northern Coastal.                    9,881, 2018).
    Bottlenose Dolphin..........  Tursiops truncatus.  Northern Gulf of     -, -, N         7,462 (0.31,               58         32  Gulf RC...........  N/A...............  N/A.
                                                        America Oceanic.                     5,769, 2018).
    Bottlenose Dolphin..........  Tursiops truncatus.  Gulf of America      -, -, N         20,759 (0.13,             167         36  Gulf RC...........  Gulf RC Inshore...  Civilian Ports:
                                                        Western Coastal.                     18,585, 2018).                                                                    Beaumont, TX,
                                                                                                                                                                               Corpus Christi,
                                                                                                                                                                               TX, Pascagoula,
                                                                                                                                                                               MS; Coast Guard
                                                                                                                                                                               Stations: Corpus
                                                                                                                                                                               Christi, TX.
    Bottlenose Dolphin..........  Tursiops truncatus.  Florida Bay........  -, -, N         UNK (UNK, UNK,            UNK        0.2  Other AFTT Areas..  N/A...............  N/A.
                                                                                             2003).
    Bottlenose Dolphin..........  Tursiops truncatus.  Indian River Lagoon  -, -, Y         1,032 (0.03,               10        5.7  Other AFTT Areas..  JAX RC Inshore....  Civilian Ports:
                                                        Estuarine.                           1,004, 2016-2017).                                                                Port Canaveral,
                                                                                                                                                                               FL.
    Bottlenose Dolphin..........  Tursiops truncatus.  Jacksonville         -, -, Y         UNK (UNK, UNK, n/         UNK          2  JAX RC............  JAX RC Inshore....  Civilian Ports:
                                                        Estuarine.                           a).                                                                               Port Canaveral,
                                                                                                                                                                               FL.
    Bottlenose Dolphin..........  Tursiops truncatus.  MS Sound, Lake       -, -, Y         1,265 (0.35, 947,         8.5         59  Gulf RC...........  Gulf Inshore......  N/A.
                                                        Borgne, Bay                          2018).
                                                        Boudreau.
    Tamanend's bottlenose         Tursiops erebennus.  Western North        -, -, Y         3,619 (0.35,               27        0.2  Other AFTT Areas..  JAX RC Inshore....  Civilian Ports:
     Dolphin.                                           Atlantic, Northern                   2,711, 2021).                                                                     Kings Bay, GA,
                                                        Florida Coastal.                                                                                                       Savannah, GA.
    Bottlenose Dolphin..........  Tursiops truncatus.  Northern GA/         -, -, Y         UNK (UNK, UNK, See        UNK        1.5  Other AFTT Areas..  JAX RC Inshore....  N/A.
                                                        Southern SC                          SAR).
                                                        Estuarine.
    Bottlenose Dolphin..........  Tursiops truncatus.  Northern Gulf of     -, -, N         63,280 (0.11,             556         65  Gulf RC...........  N/A...............  N/A.
                                                        America                              57,917, 2018).
                                                        Continental Shelf.
    Bottlenose Dolphin..........  Tursiops truncatus.  Western North        -, -, Y         6,639 (0.41,               48  12.2-21.5  VACAPES RC, Navy    VACAPES RC Inshore  Civilian Ports:
                                                        Atlantic, Northern                   4,759, 2016).                             Cherry Point RC,                        Earle, NJ,
                                                        Migratory Coastal.                                                             JAX RC, Key West                        Delaware Bay, DE,
                                                                                                                                       RC, Other AFTT                          Hampton Roads,
                                                                                                                                       Areas.                                  VA, Morehead
                                                                                                                                                                               City, NC; Coast
                                                                                                                                                                               Guard Stations:
                                                                                                                                                                               Virginia Beach,
                                                                                                                                                                               VA.
    Bottlenose Dolphin..........  Tursiops truncatus.  Northern NC          -, -, Y         823 (0.06, 782,           7.8     7.2-30  Other AFTT Areas..  N/A...............  Civilian Ports:
                                                        Estuarine.                           2017).                                                                            Morehead City,
                                                                                                                                                                               NC, Wilmington,
                                                                                                                                                                               NC.
    Bottlenose Dolphin..........  Tursiops truncatus.  Northern SC          -, -, N         453 (0.28, 359,           3.6        0.5  Other AFTT Areas..  JAX RC Inshore....  N/A.
                                                        Estuarine.                           2016).
    Bottlenose Dolphin..........  Tursiops truncatus.  Nueces Bay, Corpus   -, -, Y         58 (0.61, UNK,            UND        0.2  Gulf RC...........  N/A...............  Civilian Ports:
                                                        Christi.                             1992).                                                                            Corpus Christi,
                                                                                                                                                                               TX.
    Bottlenose Dolphin..........  Tursiops truncatus.  Sabine Lake........  -, -, N         122 (0.19, 104,           0.9          0  Gulf RC...........  N/A...............  Civilian Ports:
                                                                                             2017).                                                                            Beaumont, TX.

[[Page 19901]]

 
    Tamanend's bottlenose         Tursiops erebennus.  Western North        -, -, Y         9,121 (0.28,               73    0.2-0.6  Other AFTT Areas..  JAX RC Inshore....  Civilian Ports:
     Dolphin.                                           Atlantic South                       7,261, 2021).                                                                     Kings Bay, GA,
                                                        Carolina/Georgia                                                                                                       Savannah, GA.
                                                        Coastal.
    Bottlenose Dolphin..........  Tursiops truncatus.  Southern GA          -, -, N         UNK (UNK, UNK,            UND        0.1  Other AFTT Areas..  JAX RC Inshore....  Civilian Ports:
                                                        Estuarine System.                    2008-2009).                                                                       Kings Bay, GA,
                                                                                                                                                                               Savannah, GA.
    Bottlenose Dolphin..........  Tursiops truncatus.  Western North        -, -, Y         3,751 (0.6, 2,353,         24     0-18.3  Navy Cherry Point   JAX RC Inshore....  Civilian Ports:
                                                        Atlantic, Southern                   2016).                                    RC, JAX RC, Key                         Hampton Roads,
                                                        Migratory Coastal.                                                             West RC, Other                          VA, Morehead
                                                                                                                                       AFTT Areas.                             City, NC,
                                                                                                                                                                               Wilmington, NC,
                                                                                                                                                                               Kings Bay, GA,
                                                                                                                                                                               Savannah, GA;
                                                                                                                                                                               Coast Guard
                                                                                                                                                                               Stations:
                                                                                                                                                                               Virginia Beach,
                                                                                                                                                                               VA.
    Bottlenose Dolphin..........  Tursiops truncatus.  Southern NC          -, -, Y         UNK (UNK, UNK,            UND        0.4  Other AFTT Areas..  N/A...............  Civilian Ports:
                                                        Estuarine System.                    2017).                                                                            Morehead City,
                                                                                                                                                                               NC, Wilmington,
                                                                                                                                                                               NC.
    Bottlenose Dolphin..........  Tursiops truncatus.  Western North        -, -, N         64,587 (0.24,             507         28  Northeast RC, NUWC  N/A...............  Civilian Ports:
                                                        Atlantic Offshore                    52,801, 2021).                            Division Newport                        Morehead City,
                                                        \17\.                                                                          Testing Range,                          NC, Wilmington,
                                                                                                                                       VACAPES RC, Navy                        NC.
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, Other
                                                                                                                                       AFTT Areas.
    Bottlenose Dolphin..........  Tursiops truncatus.  Puerto Rico and      -, -, Y         UNK (UNK, UNK, N/         UNK        UNK  Other AFTT Areas..  N/A...............  N/A.
                                                        U.S. Virgin                          A).
                                                        Islands.
    Bottlenose Dolphin..........  Tursiops truncatus.  Apalachee Bay......  -, -, Y         491 (0.39, UNK,           UND          0  Gulf RC...........  N/A...............  N/A.
                                                                                             1993).
    Bottlenose Dolphin..........  Tursiops truncatus.  Barataria Bay        -, -, Y         2,071 (0.06,               18         35  Gulf RC...........  N/A...............  N/A.
                                                        Estuarine System.                    1,971, 2019).
    Bottlenose Dolphin..........  Tursiops truncatus.  Calcasieu Lake.....  -, -, Y         0 (N/A, N/A, 1992)        UND        0.2  Gulf RC...........  N/A...............  N/A.
    Bottlenose Dolphin..........  Tursiops truncatus.  Caloosahatchee       -, -, Y         0 (N/A, N/A, 1985)        UND        0.4  Gulf RC...........  N/A...............  N/A.
                                                        River.
    Bottlenose Dolphin..........  Tursiops truncatus.  Choctawhatchee Bay.  -, -, Y         179 (0.04, UNK,           UND        0.4  Gulf RC...........  N/A...............  N/A.
                                                                                             2007).
    Bottlenose Dolphin..........  Tursiops truncatus.  Chokoloskee Bay,     -, -, Y         UNK (N/A, UNK, N/         UND        0.2  Gulf RC...........  N/A...............  N/A.
                                                        Ten Thousand                         A).
                                                        Islands, Gullivan
                                                        Bay.
    Bottlenose Dolphin..........  Tursiops truncatus.  Copano Bay, Aransas  -, -, Y         55 (0.82, UNK,            UND        0.6  Gulf RC...........  N/A...............  Civilian Ports:
                                                        Bay, San Antonio                     1992).                                                                            Corpus Christi,
                                                        Bay, Redfish Bay,                                                                                                      TX.
                                                        Espiritu Santo Bay.
    Bottlenose Dolphin..........  Tursiops truncatus.  Estero Bay.........  -, -, Y         UNK (N/A, UNK, N/         UND        0.4  Gulf RC...........  N/A...............  N/A.
                                                                                             A).
    Bottlenose Dolphin..........  Tursiops truncatus.  Florida Keys.......  -, -, Y         UNK (N/A, UNK, N/         UND        0.2  Gulf RC...........  Key West Range      N/A.
                                                                                             A).                                                           Complex Inshore.
    Bottlenose Dolphin..........  Tursiops truncatus.  Galveston Bay, East  -, -, N         842 (0.08, 787,           6.3          1  Gulf RC...........  N/A...............  N/A.
                                                        Bay, Trinity Bay.                    2016).
    Bottlenose Dolphin..........  Tursiops truncatus.  Laguna Madre.......  -, -, Y         80 (1.57, UNK,            UND        0.8  Gulf RC...........  N/A...............  N/A.
                                                                                             1992).
    Bottlenose Dolphin..........  Tursiops truncatus.  Matagorda Bay, Tres  -, -, Y         61 (0.45, UNK,            UND        0.4  Gulf RC...........  N/A...............  N/A.
                                                        Palacios Bay,                        1992).
                                                        Lavaca Bay.
    Bottlenose Dolphin..........  Tursiops truncatus.  Mobile and           -, -, Y         122 (0.34, UNK,           UND         16  Gulf RC...........  N/A...............  N/A.
                                                        Bonsecour Bays.                      1993).
    Bottlenose Dolphin..........  Tursiops truncatus.  MS River Delta.....  -, -, N         1,446 (0.19,               11        9.2  Gulf RC...........  N/A...............  N/A.
                                                                                             1,238, 2018).
    Bottlenose Dolphin..........  Tursiops truncatus.  Pensacola and East   -, -, Y         33 (0.8, UNK,             UND        0.4  Gulf RC...........  N/A...............  N/A.
                                                        Bays.                                1993).
    Bottlenose Dolphin..........  Tursiops truncatus.  Perdido Bay........  -, -, Y         0 (N/A, N/A, 1993)        UND        0.8  Gulf RC...........  N/A...............  N/A.
    Bottlenose Dolphin..........  Tursiops truncatus.  Pine Island Sound,   -, -, Y         826 (0.09, UNK,           UND          1  Gulf RC...........  N/A...............  N/A.
                                                        Charlotte Harbor,                    2006).
                                                        Gasparilla Sound,
                                                        Lemon Bay.
    Bottlenose Dolphin..........  Tursiops truncatus.  Sarasota Bays......  -, -, N         158 (0.27, 126,             1        0.2  Gulf RC...........  N/A...............  N/A.
                                                                                             2015).

[[Page 19902]]

 
    Bottlenose Dolphin..........  Tursiops truncatus.  St. Andrew Bay.....  -, -, N         199 (0.09, 185,           1.5        0.2  Gulf RC...........  Gulf Inshore......  N/A.
                                                                                             2016).
    Bottlenose Dolphin..........  Tursiops truncatus.  St. Joseph Bay.....  -, -, N         142 (0.17, 123,             1        UNK  Gulf RC...........  N/A...............  N/A.
                                                                                             2011).
    Bottlenose Dolphin..........  Tursiops truncatus.  St. Joseph Sound,    -, -, Y         UNK (N/A, UNK, N/         UND        0.8  Gulf RC...........  N/A...............  N/A.
                                                        Clearwater Harbor.                   A).
    Bottlenose Dolphin..........  Tursiops truncatus.  St. Vincent Sound,   -, -, Y         439 (0.14, UNK,           UND        0.2  Gulf RC...........  N/A...............  N/A.
                                                        Apalachicola Bay,                    2007).
                                                        St. George Sound.
    Bottlenose Dolphin..........  Tursiops truncatus.  Tampa Bay..........  -, -, Y         UNK (N/A, UNK, N/         UND          3  Gulf RC...........  N/A...............  Civilian Ports:
                                                                                             A).                                                                               Tampa, FL.
    Bottlenose Dolphin..........  Tursiops truncatus.  Terrebonne and       -, -, N         3,870 (0.15,               27        0.2  Gulf RC...........  N/A...............  N/A.
                                                        Timbalier Bays                       3,426, 2016).
                                                        Estuarine System.
    Bottlenose Dolphin..........  Tursiops truncatus.  Vermillion Bay,      -, -, Y         0 (N/A, N/A, 1992)        UND          0  Gulf RC...........  Gulf Inshore......  N/A.
                                                        West Cote Blanche
                                                        Bay, Atchafalaya
                                                        Bay.
    Bottlenose Dolphin..........  Tursiops truncatus.  Waccasassa Bay,      -, -, Y         UNK (N/A, UNK, N/         UND        0.4  Gulf RC...........  N/A...............  N/A.
                                                        Withlacoochee Bay,                   A).
                                                        Crystal Bay.
    Bottlenose Dolphin..........  Tursiops truncatus.  West Bay...........  -, -, N         37 (0.05, 35,             0.3          0  Gulf RC...........  N/A...............  N/A.
                                                                                             2015).
    Bottlenose Dolphin..........  Tursiops truncatus.  Whitewater Bay.....  -, -, Y         UNK (N/A, UNK, N/         UND          0  Gulf RC...........  N/A...............  N/A.
                                                                                             A).
    Clymene Dolphin.............  Stenella clymene...  Northern Gulf of     -, -, Y         513 (1.03, 250,           2.5        8.4  Gulf RC, Other      N/A...............  N/A.
                                                        America.                             2018).                                    AFTT Areas.
    Clymene Dolphin.............  Stenella clymene...  Western North        -, -, N         21,778 (0.72,             126          0  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            12,622, 2021).                            Division, Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Common Dolphin..............  Delphinus delphis..  Western North        -, -, N         93,100 (0.56,           1,452        414  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            59,897, 2021).                            Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    False Killer Whale..........  Pseudorca            Northern Gulf of     -, -, N         494 (0.79, 276,           2.8        2.2  Gulf RC, Other      N/A...............  N/A.
                                   crassidens.          America.                             2018).                                    AFTT Areas.
    False Killer Whale..........  Pseudorca            Western North        -, -, N         1,298 (0.72, 775,         7.6          0  NUWC Division,      N/A...............  N/A.
                                   crassidens.          Atlantic.                            2021).                                    Newport Testing
                                                                                                                                       Range, VACAPES
                                                                                                                                       RC, Navy Cherry
                                                                                                                                       Point RC, JAX RC,
                                                                                                                                       SFOMF, Key West
                                                                                                                                       RC, NSWC Panama
                                                                                                                                       City Division
                                                                                                                                       Testing Range,
                                                                                                                                       Gulf RC, Other
                                                                                                                                       AFTT Areas.
    Fraser's Dolphin............  Lagenodelphis hosei  Northern Gulf of     -, -, N         213 (1.03, 104,             1        UNK  Gulf RC...........  N/A...............  N/A.
                                                        America.                             2018).

[[Page 19903]]

 
    Fraser's Dolphin............  Lagenodelphis hosei  Western North        -, -, N         UNK (UNK, UNK,            UNK          0  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            2021).                                    Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Killer Whale................  Orcinus orca.......  Northern Gulf of     -, -, N         267 (0.75, 152,           1.5        UNK  Gulf RC...........  N/A...............  N/A.
                                                        America.                             2018).
    Killer Whale................  Orcinus orca.......  Western North        -, -, N         UNK (UNK, UNK,            UNK          0  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            2016).                                    Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Long-Finned Pilot Whale.....  Globicephala melas.  Western North        -, -, N         39,215 (0.30,             306        5.7  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            30,627, 2021).                            Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Melon-Headed Whale..........  Peponocephala        Northern Gulf of     -, -, N         1,749 (0.68,               10        9.5  Gulf RC...........  N/A...............  N/A.
                                   electra.             America.                             1,039, 2018).
    Melon-Headed Whale..........  Peponocephala        Western North        -, -, N         UNK (UNK, UNK,            UNK          0  Northeast RC, NUWC  N/A...............  N/A.
                                   electra.             Atlantic.                            2021).                                    Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Pantropical Spotted Dolphin.  Stenella attenuata.  Northern Gulf of     -, -, N         37,195 (0.24,             304        241  Gulf RC...........  N/A...............  N/A.
                                                        America.                             30,377, 2018).
    Pantropical Spotted Dolphin.  Stenella attenuata.  Western North        -, D, N         2,757 (0.50,               19          0  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            1,856, 2021).                             Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Pygmy Killer Whale..........  Feresa attenuata...  Northern Gulf of     -, -, N         613 (1.15, 283,           2.8        1.6  Gulf RC...........  N/A...............  N/A.
                                                        America.                             2018).
    Pygmy Killer Whale..........  Feresa attenuata...  Western North        -, -, N         UNK (UNK, UNK,            UNK          0  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            2021).                                    Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Risso's Dolphin.............  Grampus griseus....  Northern Gulf of     -, -, N         1,974 (0.46,               14        5.3  Gulf RC...........  N/A...............  N/A.
                                                        America.                             1,368, 2018).

[[Page 19904]]

 
    Risso's Dolphin.............  Grampus griseus....  Western North        -, -, N         44,067 (0.19,             307         18  Northeast RC, NUWC  N/A...............  N/A.
                                                        Atlantic.                            30,662, 2021).                            Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Rough-Toothed Dolphin.......  Steno bredanensis..  Northern Gulf of     -, -, N         UNK (N/A, UNK,            UND         39  Gulf RC...........  N/A...............  N/A.
                                                        America.                             2018).
    Rough-Toothed Dolphin.......  Steno bredanensis..  Western North        -, -, N         UNK (UNK, UNK,            UND          0  Navy Cherry Point   N/A...............  N/A.
                                                        Atlantic.                            2021).                                    RC, JAX RC,
                                                                                                                                       SFOMF, Key West
                                                                                                                                       RC, NSWC Panama
                                                                                                                                       City Division
                                                                                                                                       Testing Range,
                                                                                                                                       Gulf RC, Other
                                                                                                                                       AFTT Areas.
    Short-Finned Pilot Whale....  Globicephala         Northern Gulf of     -, -, N         1,321 (0.43, 934,         7.5        3.9  Gulf RC...........  N/A...............  N/A.
                                   macrorhynchus.       America.                             2018).
    Short-Finned Pilot Whale....  Globicephala         Puerto Rico and      -, -, Y         UNK (UNK, UNK, N/         UNK        UNK  Other AFTT Areas..  N/A...............  N/A.
                                   macrorhynchus.       U.S. Virgin                          A).
                                                        Islands.
    Short-Finned Pilot Whale....  Globicephala         Western North        -, -, Y         18,726 (0.33,             143        218  Northeast RC, NUWC  N/A...............  N/A.
                                   macrorhynchus.       Atlantic.                            14,292, 2021).                            Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Spinner Dolphin.............  Stenella             Northern Gulf of     -, -, Y         2,991 (0.54,               20        113  Gulf RC...........  N/A...............  N/A.
                                   longirostris.        America.                             1,954, 2018).
    Spinner Dolphin.............  Stenella             Puerto Rico and      -, -, Y         UNK (UNK, UNK, N/         UNK        UNK  Other AFTT Areas..  N/A...............  N/A.
                                   longirostris.        U.S. Virgin                          A).
                                                        Islands.
    Spinner Dolphin.............  Stenella             Western North        -, D, N         3,181 (0.65,               19          0  Northeast RC, NUWC  N/A...............  N/A.
                                   longirostris.        Atlantic.                            1,930, 2021).                             Division, Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
    Striped Dolphin.............  Stenella             Northern Gulf of     -, -, Y         1,817 (0.56,               12         13  Gulf RC...........  N/A...............  N/A.
                                   coeruleoalba.        America.                             1,172, 2018).
    Striped Dolphin.............  Stenella             Western North        -, -, N         48,274 (0.29,             529          0  Northeast RC, NUWC  N/A...............  N/A.
                                   coeruleoalba.        Atlantic.                            38,040, 2021).                            Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.

[[Page 19905]]

 
    White-Beaked Dolphin........  Lagenorhynchus       Western North        -, -, N         536,016 (0.31,          4,153          0  Northeast RC, NUWC  N/A...............  N/A.
                                   albirostris.         Atlantic.                            415,344, 2016).                           Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC,
                                                                                                                                       JAX RC, SFOMF,
                                                                                                                                       Key West RC, NSWC
                                                                                                                                       Panama City
                                                                                                                                       Division Testing
                                                                                                                                       Range, Gulf RC,
                                                                                                                                       Other AFTT Areas.
Family Phocoenidae (porpoises):
    Harbor Porpoise.............  Phocoena phocoena..  Gulf of Maine/Bay    -, -, N         85,765 (0.53,             649      142.4  Northeast RC, NUWC  Northeast RC        Civilian Ports:
                                                        of Fundy.                            56,420, 2021).                            Division Newport    Inshore, VACAPES    Boston, MA,
                                                                                                                                       Testing Range,      RC Inshore, JAX     Earle, NJ,
                                                                                                                                       VACAPES RC, Navy    RC Inshore.         Delaware Bay, DE,
                                                                                                                                       Cherry Point RC.                        Hampton Roads,
                                                                                                                                                                               VA; Coast Guard
                                                                                                                                                                               Stations: Boston,
                                                                                                                                                                               MA, Virginia
                                                                                                                                                                               Beach, VA.
    Harbor Porpoise.............  Phocoena phocoena..  Greenland..........  (18 19 20)      ..................  .........  .........  Other AFTT Areas..
    Harbor Porpoise.............  Phocoena phocoena..  Gulf of St.          (18 19 20)      ..................  .........  .........  Other AFTT Areas..
                                                        Lawrence.
    Harbor Porpoise.............  Phocoena phocoena..  Newfoundland.......  (18 19 20)      ..................  .........  .........  Other AFTT Areas..
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                   Order Carnivora--Pinnipedia
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Family Phocidae (earless seals):
    Gray Seal...................  Halichoerus grypus.  Western North        -, -, N         27,911 (0.20,             756      4,491  Northeast RC, NUWC  Northeast RC        Civilian Ports:
                                                        Atlantic.                            23,624, 2021).                            Division Newport    Inshore, VACAPES    Boston, MA,
                                                                                                                                       Testing Range,      RC Inshore, JAX     Earle, NJ,
                                                                                                                                       VACAPES RC, Navy    RC Inshore.         Delaware Bay, DE,
                                                                                                                                       Cherry Point RC.                        Hampton Roads,
                                                                                                                                                                               VA, Morehead
                                                                                                                                                                               City, NC; Coast
                                                                                                                                                                               Guard Stations:
                                                                                                                                                                               Boston, MA,
                                                                                                                                                                               Virginia Beach,
                                                                                                                                                                               VA.
    Harbor Seal.................  Phoca vitulina.....  Western North        -, -, N         61,336 (0.08,           1,729        339  Northeast RC, NUWC  Northeast RC        Civilian Ports:
                                                        Atlantic.                            57,637, 2018).                            Division Newport    Inshore, VACAPES    Boston, MA,
                                                                                                                                       Testing Range,      RC Inshore, JAX     Earle, NJ,
                                                                                                                                       VACAPES RC, Navy    RC Inshore.         Delaware Bay, DE,
                                                                                                                                       Cherry Point RC.                        Hampton Roads,
                                                                                                                                                                               VA, Morehead
                                                                                                                                                                               City, NC; Coast
                                                                                                                                                                               Guard Stations:
                                                                                                                                                                               Boston, MA,
                                                                                                                                                                               Virginia Beach,
                                                                                                                                                                               VA.
    Harp Seal...................  Pagophilus           Western North        -, -, N         7.6M (UNK, 7.1M,      426,000    178,573  Northeast RC, NUWC  N/A...............  N/A.
                                   groenlandicus.       Atlantic.                            2019).                                    Division Newport
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC.
    Hooded Seal.................  Cystophora cristata  Western North        -, -, N         UNK (UNK, UNK, n/         UNK      1,680  Northeast RC, NUWC  N/A...............  Civilian Ports:
                                                        Atlantic.                            a).                                       Division Newport                        Boston, MA.
                                                                                                                                       Testing Range,
                                                                                                                                       VACAPES RC, Navy
                                                                                                                                       Cherry Point RC.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: %: percent; AFTT: Atlantic Fleet Training and Testing; CV: coefficient of variation; EEZ: Exclusive Economic Zone; EIS: Environmental Impact Statement; ESA: Endangered Species Act; JAX:
  Jacksonville; Min.: minimum; MMPA: Marine Mammal Protection Act; NMFS: National Marine Fisheries Service; NSWC: Naval Surface Warfare Center; NUWC: Naval Undersea Warfare Center; RC: Range
  Complex; SAR: Stock Assessment Report; SFOMF: Naval Surface Warfare Center, Carderock Division, South Florida Ocean Measurement Facility Testing Range; U.S.: United States; USFWS: U.S. Fish
  and Wildlife Service; VACAPES: Virginia Capes. Marine mammals in the Gulf of America are named in the most recent SARs (Hayes et al., 2024) with reference to the formerly named ``Gulf of
  Mexico.'' This Notice refers to these marine mammal stocks as Northern Gulf of America stocks. The geographical location of the stocks remains the same.
\1\ Information on the classification of marine mammal species can be found on the web page for The Society for Marine Mammalogy's Committee on Taxonomy (https://marinemammalscience.org/science-and-publications/list-marine-mammal-species-subspecies/).
\2\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed under the ESA or designated as depleted
  under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality exceeds PBR or which is determined to be declining and likely to be listed under
  the ESA within the foreseeable future. Any species or stock listed under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\3\ NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region. CV is coefficient of
  variation; Nmin is the minimum estimate of stock abundance.
\4\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial fisheries, vessel strike). Annual M/SI
  often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV associated with estimated mortality due to commercial fisheries is presented in some
  cases.
\5\ NMFS uses ``credible interval'' to characterize the uncertainty as opposed to CV for North Atlantic right whales (Hayes et al., 2024).
\6\ Photo-ID catalog count of 402 recognizable blue whale individuals from the Gulf of St. Lawrence is considered a minimum population estimate for the western North Atlantic stock (Waring et
  al., 2010). An additional 39 (0.64) were documented in the summer of 2016 for Central Virginia to Bay of Fundy (Waring et al., 2010).
\7\ The West Greenland stock of fin whales is not managed by NMFS and, therefore, does not have an associated Stock Assessment Report. Abundance and a 95% confidence interval were presented in
  Heide-Jorgensen et al. (2010a).
\8\ The Gulf of St. Lawrence stock of fin whales is not managed by NMFS and, therefore, does not have an associated Stock Assessment Report. Abundance and 95% confidence interval were
  presented in Ramp et al. (2014).
\9\ The West Greenland stock of minke whales is not managed by NMFS and, therefore, does not have an associated Stock Assessment Report. Abundance and 95% confidence interval were presented in
  Heide-Jorgensen et al. (2010b).
\10\ Total M/SI is a minimum estimate and does not include Fisheries M/SI.
\11\ The Labrador Sea stock of sei whales is not managed by NMFS and, therefore, does not have an associated Stock Assessment Report. Information was obtained in Prieto et al. (2014).

[[Page 19906]]

 
\12\ Because Kogia sima and K. breviceps are difficult to differentiate at sea, the reported abundance estimates for the Western North Atlantic stock are for both species of Kogia combined.
\13\ Because Kogia sima and K. breviceps are difficult to differentiate at sea, the reported abundance estimates for the Northern Gulf of America stock are for both species of Kogia combined.
\14\ Estimate includes undifferentiated Mesoplodon species.
\15\ Estimate includes Gervais' and Blainville's beaked whales.
\16\ There are 32 stocks within the bottlenose dolphin Gulf of America Bay, Sound, and Estuaries strategic stock and there are no stock-specific SARs available at this time.
\17\ Estimate may include sightings of the coastal form.
\18\ Harbor porpoises in the Gulf of St. Lawrence are not managed by NMFS and have no associated Stock Assessment Report.
\19\ Harbor porpoises in Newfoundland are not managed by NMFS and have no associated Stock Assessment Report.
\20\ Harbor porpoises in Greenland are not managed by NMFS and have no associated Stock Assessment Report.


[[Page 19907]]

Species Not Included in the Analysis

    The species carried forward for analysis (and described in table 
14) are those likely to be found in the AFTT Study Area based on the 
most recent data available and do not include species that may have 
once inhabited or transited the area but have not been sighted in 
recent years (e.g., species which were extirpated from factors such as 
19th and 20th century commercial exploitation). Several species that 
may be present in the northwestern Atlantic Ocean have an extremely low 
probability of presence in the AFTT Study Area. These species are 
considered extralimital (not anticipated to occur in the Study Area) or 
rare (occur in the Study Area sporadically, but sightings are rare). 
These extralimital species include the bowhead whale (Balaena 
mysticetus), beluga whale (Delphinapterus leucas), narwhal (Monodon 
monoceros), ringed seal (Pusa hispida), and bearded seal (Erignathus 
barbatus). Bowhead whales are likely to be found only in the Labrador 
Current open ocean area but, in 2012 and 2014, the same bowhead whale 
was observed in Cape Cod Bay, which represents the southernmost record 
of this species in the western North Atlantic. In June 2014, a beluga 
whale was observed in several bays and inlets of Rhode Island and 
Massachusetts (Swaintek, 2014). This sighting likely represents an 
extralimital beluga whale occurrence in the Northeast United States 
Continental Shelf Large Marine Ecosystem. Narwhals prefer cold Arctic 
waters, and there is no stock of narwhal that occurs in the U.S. EEZ in 
the Atlantic Ocean; however, populations from Hudson Strait and Davis 
Strait may extend into the AFTT Study Area at its northwest extreme and 
those that winter in Hudson Strait likely occur in smaller numbers.
    In addition to the species listed above, several stocks that did 
not overlap areas in or near modeled activities in the AFTT Study Area 
were not analyzed. These stocks include the West Greenland and Gulf of 
St. Lawrence stocks of fin whale; the West Greenland stock of minke 
whale; the Labrador Sea stock of sei whale; and the Gulf of St. 
Lawrence, Newfoundland, and Greenland stocks of harbor porpoise. NMFS 
agrees with the Action Proponents' assessment that these species are 
unlikely to occur in the AFTT Study Area, and they are not discussed 
further. Further, neither NMFS nor Navy anticipates take of the Puerto 
Rico/U.S. Virgin Islands stock of sperm whale, as U.S. Navy training 
activities in the Vieques Naval Training Range ceased in 2003.
    Three species of marine mammals, walrus (Odobenus rosmarus), West 
Indian manatee (Trichechus manatus), and polar bear (Ursus maritimus), 
occur in the AFTT Study Area, but are managed by the U.S. Fish and 
Wildlife Service (U.S. FWS), and thus are not considered further in 
this document.
    Below, we consider additional information about the marine mammals 
in the area of the specified activities that informs our analysis, such 
as identifying known areas of important habitat or behaviors, or where 
Unusual Mortality Events (UME) have been designated.

Critical Habitat

    Currently, only the NARW has ESA-designated critical habitat in the 
AFTT Study Area. However, NMFS has recently published a proposed rule 
proposing new ESA-designated critical habitat for the Rice's whale (88 
FR 47453, July 24, 2023).
North Atlantic Right Whale
    On February 26, 2016, NMFS issued a final rule (81 FR 4838) to 
replace the critical habitat for NARW with two new areas. The areas now 
designated as critical habitat contain approximately 29,763 nmi\2\ 
(102,084 km\2\) of marine habitat in the Gulf of Maine and Georges Bank 
region (Unit 1), essential for NARW foraging and off the Southeast U.S. 
coast (Unit 2), including the coast of North Carolina, South Carolina, 
Georgia, and Florida, which are key areas essential for calving. These 
two ESA-designated critical habitats were established to replace three 
smaller previously ESA-designated critical habitats (Cape Cod Bay/
Massachusetts Bay/Stellwagen Bank, Great South Channel, and the coastal 
waters of Georgia and Florida in the southeastern United States) that 
had been designated by NMFS in 1994 (59 FR 28805, June 3, 1994). Two 
additional areas in Canadian waters, Grand Manan Basin and Roseway 
Basin, were identified and designated as critical habitat under 
Canada's endangered species law (section 58 (5) of the Species at Risk 
Act (SARA), S. C. 2002, c. 29) and identified in Final Recovery 
Strategy for the NARW, posted June 2009 on the SARA Public Registry.
    Unit 1 encompasses the Gulf of Maine and Georges Bank region 
including the large embayments of Cape Cod Bay and Massachusetts Bay 
and deep underwater basins, as well as state waters, except for inshore 
areas, bays, harbors, and inlets, from Maine through Massachusetts in 
addition to Federal waters, all of which are key areas (see figure 4.1-
1 of the application). It also does not include waters landward of the 
72 COLREGS lines (33 CFR part 80). The essential physical and 
biological features of foraging habitat for NARW are: (1) The physical 
oceanographic conditions and structures of the Gulf of Maine and 
Georges Bank region that combine to distribute and aggregate Calanus 
finmarchicus for right whale foraging, namely prevailing currents and 
circulation patterns, bathymetric features (basins, banks, and 
channels), oceanic fronts, density gradients, and temperature regimes; 
(2) low flow velocities in Jordan, Wilkinson, and Georges Basins that 
allow diapausing C. finmarchicus to aggregate passively below the 
convective layer so that the copepods are retained in the basins; (3) 
late stage C. finmarchicus in dense aggregations in the Gulf of Maine 
and Georges Bank region; and (4) diapausing C. finmarchicus in 
aggregations in the Gulf of Maine and Georges Bank region.
    Unit 2 consists of all marine waters from Cape Fear, North 
Carolina, southward to approximately 27 nmi below Cape Canaveral, 
Florida, within the area bounded on the west by the shoreline and the 
72 COLREGS lines, and on the east by rhumb lines connecting the 
specific points described below (see figure 4.1-2 of the application). 
The essential physical and biological features correlated with the 
distribution of NARW in the southern critical habitat area provide an 
optimum environment for calving. These are: (1) Calm sea surface 
conditions of Force 4 or less on the Beaufort Wind Scale; (2) sea 
surface temperatures from a minimum of 44.6 [deg]F (7 [deg]C), and 
never more than 62.6 [deg]F (17 [deg]C); and (3) water depths of 19.7 
to 91.9 ft (6 to 28 m), where these features simultaneously co-occur 
over contiguous areas of at least 231 nmi\2\ (792.3 km\2\) of ocean 
waters during the months of November through April. For example, the 
bathymetry of the inner and nearshore middle shelf area minimizes the 
effect of strong winds and offshore waves, limiting the formation of 
large waves and rough water. The average temperature of critical 
habitat waters is cooler during the time right whales are present due 
to a lack of influence by the Gulf Stream and cool freshwater runoff 
from coastal areas. The water temperatures may provide an optimal 
balance between offshore waters that are too warm for nursing mothers 
to tolerate, yet not too cool for calves that may only have minimal 
fatty insulation. Reproductive females and calves are expected to be 
concentrated in the critical habitat from December through April.

[[Page 19908]]

Rice's Whale
    On August 23, 2021, NMFS published a final rule that revised the 
listing of Rice's whales under the ESA to reflect the change in the 
scientifically accepted taxonomy and nomenclature of this species (86 
FR 47022). Prior to this revision, the Rice's whale was listed in 2019 
under the ESA as an endangered subspecies of the Bryde's whale (Gulf of 
America subspecies (referred to as the Gulf of Mexico subspecies in 86 
FR 47022)). The 2019 listing rule indicated that, with a total 
abundance of approximately 100 individuals, small population size and 
restricted range are the most serious threats to this species (84 FR 
15446, April 15, 2019). However, other threats such as energy 
exploration, development, and production; oil spills and oil spill 
responses; vessel collision; fishing gear entanglement; and 
anthropogenic noise were also identified as threats that contribute to 
the risk of extinction.
    The specific occupied areas proposed for designation as critical 
habitat for the Rice's whale contain approximately 28,270.65 mi\2\ 
(73,220.65 km\2\) of continental shelf and slope associated waters 
between 100 m and 400 m (328 ft and 1,312 ft) isobaths within the Gulf 
of America spanning from the U.S. EEZ boundary off the southwestern 
coast of Texas, to the boundary between the South Atlantic Fishery 
Management Council and the Gulf Fishery Management Council off the 
southeastern coast of Florida.
    In the final listing rule, NMFS stated that critical habitat was 
not determinable at the time of the listing, because sufficient 
information was not currently available on the geographical area 
occupied by the species (84 FR 15446, April 15, 2019). On July 24, 
2023, NMFS published a proposed rule describing the proposed critical 
habitat designation, including supporting information on Rice's whale 
biology, distribution, and habitat use, and the methods used to develop 
the proposed designation (88 FR 47453). The physical and biological 
features essential to the conservation of the species identified in the 
proposed rule are:
    (i) Sufficient density, quality, abundance, and accessibility of 
small demersal and vertically migrating prey species, including 
scombriformes, stomiiformes, myctophiformes, and myopsida;
    (ii) Marine water with:
    A. Elevated productivity,
    B. Bottom temperatures of 50-66.2 [deg]F (10-19 [deg]C), and
    C. Levels of pollutants that do not preclude or inhibit any 
demographic function; and
    (iii) Sufficiently quiet conditions for normal use and occupancy, 
including intraspecific communication, navigation, and detection of 
prey, predators, and other threats.

Biologically Important Areas

    LaBrecque et al. (2015) identified Biologically Important Areas 
(BIAs) within U.S. waters of the East Coast and Gulf of America, which 
represent areas and times in which cetaceans are known to concentrate 
in areas of known importance for activities related to reproduction, 
feeding, and migration, or areas where small and resident populations 
are known to occur. Unlike ESA critical habitat, these areas are not 
formally designated pursuant to any statute or law, but are a 
compilation of the best available science intended to inform impact and 
mitigation analyses. An interactive map of the BIAs is available here: 
https://oceannoise.noaa.gov/biologically-important-areas. In some 
cases, additional, or newer, information regarding known feeding, 
breeding, or migratory areas may be available, and is included below.
    On the East Coast, 19 of the 24 identified BIAs fall within or 
overlap with the AFTT Study Area: 10 feeding (2 for minke whale, 1 for 
sei whale, 3 for fin whale, 3 for NARW, and 1 for humpback), 1 
migration (NARW), 2 reproduction (NARW), and 6 small and resident 
population (1 for harbor porpoise and 5 for bottlenose dolphin). 
Figures 4.1-1 through 4.1-14 of the application illustrate how these 
BIAs overlap with OPAREAs on the East Coast. In the Gulf of America, 4 
of the 12 identified BIAs for small and resident populations overlap 
the AFTT Study Area (1 for Rice's (Bryde's) whale and 3 for bottlenose 
dolphin). Figures 4.1-9 through 4.1-13 of the application illustrates 
how these BIAs overlap with OPAREAs in the Gulf of America.
Large Whales Feeding BIAs--East Coast
    Two minke whale feeding BIAs are located in the northeast Atlantic 
from March through November in waters less than 200 m (656 ft) in the 
southern and southwestern section of the Gulf of Maine including 
Georges Bank, the Great South Channel, Cape Cod Bay and Massachusetts 
Bay, Stellwagen Bank, Cape Anne, and Jeffreys Ledge (LaBrecque et al., 
2015a; LaBrecque et al., 2015b). LaBrecque et al. (2015b) delineated a 
feeding area for sei whales in the northeast Atlantic between the 25-m 
(82-ft) contour off coastal Maine and Massachusetts to the 200-m (656-
ft) contour in central Gulf of Maine, including the northern shelf 
break area of Georges Bank. The feeding area also includes the southern 
shelf break area of Georges Bank from 100-2,000 m (328-6,562 ft) and 
the Great South Channel. Feeding activity is concentrated from May 
through November with a peak in July and August. LaBrecque et al. 
(2015b) identified three feeding areas for fin whales in the North 
Atlantic within the AFTT Study Area: (1) June to October in the 
northern Gulf of Maine, (2) year-round in the southern Gulf of Maine, 
and (3) March to October east of Montauk Point. LaBrecque et al. 
(2015b) delineated a humpback whale feeding area in the Gulf of Maine, 
Stellwagen Bank, and Great South Channel.
North Atlantic Right Whale BIAs--East Coast and Additional Information
    LaBrecque et al. (2015b) identified three seasonal NARW feeding 
areas BIAs located in or near the AFTT Study Area (1) February to April 
on Cape Cod Bay and Massachusetts Bay, (2) April to June in the Great 
South Channel and on the northern edge of Georges Bank, and (3) June to 
July and October to December on Jeffreys Ledge in the western Gulf of 
Maine. A mating BIA was identified in the central Gulf of Maine (from 
November through January), a calving BIA in the southeast Atlantic 
(from mid-November to late April), and the migratory corridor area BIA 
along the U.S. East Coast between the NARW southern calving grounds and 
northern feeding areas (see figures 4.1-1 through 4.1-14 of the 
application for how these BIAs overlap with Navy OPAREAs).
    In addition to the BIAs described above, an area south of Martha's 
Vineyard and Nantucket, primarily along the western side of Nantucket 
Shoals, was recently described as an important feeding area (Kraus et 
al., 2016; O'Brien et al., 2022, Quintano-Rizzo et al., 2021). Its 
importance as a foraging habitat is well established (Leiter et al., 
2017; Estabrook et al., 2022; O'Brien et al., 2022). Nantucket Shoals' 
unique oceanographic and bathymetric features, including a persistent 
tidal front, help sustain year-round elevated phytoplankton biomass and 
aggregate zooplankton prey for NARW (White et al., 2020; Quintana-Rizzo 
et al., 2021). O'Brien et al. (2022) hypothesize that NARW southern New 
England habitat use has increased in recent years (i.e., over the last 
decade) as a result of either, or a combination of, a northward shift 
in prey distribution (thus increasing local prey availability) or a 
decline in prey in other abandoned feeding areas (e.g., Gulf of Maine), 
both induced by climate change. Pendleton et al. (2022) characterize 
southern New

[[Page 19909]]

England as a ``waiting room'' for NARW in the spring, providing 
sufficient, although sub-optimal, prey choices while NARW wait for C. 
finmarchicus supplies in Cape Cod Bay (and other primary foraging 
grounds like the Great South Channel) to optimize as seasonal primary 
and secondary production progresses. Throughout the year, southern New 
England provides opportunities for NARW to capitalize on C. 
finmarchicus blooms or alternative prey (e.g., Pseudocalanus elongatus 
and Centropages species, found in greater concentrations than C. 
finmarchicus in winter), although likely not to the extent provided 
seasonally in more well-understood feeding habitats like Cape Cod Bay 
in late spring or the Great South Channel (O'Brien et al., 2022). 
Although extensive data gaps, highlighted in a recent report by the 
National Academy of Sciences (NAS) (2023), have prevented development 
of a thorough understanding of NARW foraging ecology in the Nantucket 
Shoals region, it is clear that the habitat was historically valuable 
to the species based on historical whaling records, and observations 
over the last decade confirm the area's importance as a feeding 
habitat.
Harbor Porpoise BIA--East Coast
    LaBrecque et al. (2015b) identified a small and resident population 
BIA for harbor porpoise in the Gulf of Maine (see figure 4.1-14 of the 
application). From July to September, harbor porpoises are concentrated 
in waters less than 150 m (492 ft) deep in the northern Gulf of Maine 
and southern Bay of Fundy. During fall (October to December) and spring 
(April to June), harbor porpoises are widely dispersed from New Jersey 
to Maine, with lower densities farther north and south (LaBrecque et 
al., 2015b).
Bottlenose Dolphin BIA--East Coast
    LaBrecque et al. (2015b) identified nine small and resident 
bottlenose dolphin population areas within estuarine areas along the 
east coast of the U.S. (see figure 4.1-11 of the application). These 
areas include estuarine and nearshore areas extending from Pamlico 
Sound, North Carolina down to Florida Bay, Florida (LaBrecque et al., 
2015b). The Northern North Carolina Estuarine System, Southern North 
Carolina Estuarine System, and Charleston Estuarine System populations 
partially overlap with nearshore portions of the Navy Cherry Point 
Range Complex and Jacksonville Estuarine System Populations partially 
overlaps with nearshore portions of the Jacksonville Range Complex. The 
Southern Georgia Estuarine System Population area also overlaps with 
the Jacksonville Range Complex, specifically within Naval Submarine 
Base Kings Bay, Kings Bay, Georgia and includes estuarine and 
intercoastal waterways from Altamaha Sound, to the Cumberland River 
(LaBrecque et al., 2015b). The remaining four BIAs are outside but 
adjacent to the AFTT Study Area boundaries.
Bottlenose Dolphin BIA--Gulf of America
    LaBrecque et al. (2015) also described 11 year-round BIAs for small 
and resident estuarine stocks of bottlenose dolphin that primarily 
inhabit inshore waters of bays, sounds, and estuaries (BSE) in the Gulf 
of America (see figures 4.1-12 and 4.1-13 in the application). Of the 
11 BIAs identified for the BSE bottlenose dolphins in the Gulf of 
America, three overlap with the Gulf Range Complex (Aransas Pass Area, 
Texas; Mississippi Sound Area, Mississippi; and St. Joseph Bay Area, 
Florida), while eight are located adjacent to the AFTT Study Area 
boundaries.
Rice's (Previously Bryde's) Whale BIA--Gulf of America
    The Rice's (previously Bryde's) whale is a very small population 
that is genetically distinct from Bryde's whales and not genetically 
diverse within the Gulf of America (Rosel and Wilcox, 2014; Rosel et 
al., 2021). Further, the species is typically observed only within a 
narrowly circumscribed area within the eastern Gulf of America. 
Therefore, this area is described as a year-round BIA by LaBrecque et 
al. (2015). Previous survey effort covered all oceanic waters of the 
U.S. Gulf of America, and whales were observed only between 
approximately the 100- and 300-m (328- and 984-ft) isobaths in the 
eastern Gulf of America from the head of the De Soto Canyon (south of 
Pensacola, Florida) to northwest of Tampa Bay, Florida (Maze-Foley and 
Mullin, 2006; Waring et al., 2016; Rosel and Wilcox, 2014; Rosel et 
al., 2016). Rosel et al. (2016) expanded this description by stating 
that, due to the depth of some sightings, the area is more 
appropriately defined to the 400-m (1,312-ft) isobath and westward to 
Mobile Bay, Alabama, in order to provide some buffer around the deeper 
sightings and to include all sightings in the northeastern Gulf of 
America. Since then, passive acoustic detections of Rice's whale have 
occurred in the north central and western Gulf of America (Soldevilla 
et al., 2022; Soldevilla et al., 2024), although the highest densities 
of Rice's whales have been confined to the northeastern Gulf of America 
core habitat. The number of individuals that occur in the central and 
western Gulf of America and nature of their use of this area is poorly 
understood. Soldevilla et al. (2022) suggest that more than one 
individual was present on at least one occasion, as overlapping calls 
of different call subtypes were recorded in that instance, but also 
state that call detection rates suggest that either multiple 
individuals are typically calling or that individual whales are 
producing calls at higher rates in the central and western Gulf of 
America. Soldevilla et al. (2024) provide further evidence that Rice's 
whale habitat encompasses all 100-400 m (328-1,312 ft) depth waters 
encircling the entire Gulf of America, including Mexican waters (as 
described in the proposed critical habitat designation (88 FR 47453, 
July 24, 2023)), but they also note that further research is needed to 
understand the density of whales in these areas, seasonal changes in 
whale density, and other aspects of habitat usage.

National Marine Sanctuaries

    Under Title III of the Marine Protection, Research, and Sanctuaries 
Act of 1972 (also known as the National Marine Sanctuaries Act (NMSA)), 
NOAA can establish as national marine sanctuaries (NMS) areas of the 
marine environment with special conservation, recreational, ecological, 
historical, cultural, archaeological, scientific, educational, or 
aesthetic qualities. Sanctuary regulations prohibit destroying, causing 
the loss of, or injuring any sanctuary resource managed under the law 
or regulations for that sanctuary (15 CFR part 922). NMS are managed on 
a site-specific basis, and each sanctuary has site-specific 
regulations. Most, but not all sanctuaries have site-specific 
regulatory exemptions from the prohibitions for certain military 
activities. Separately, section 304(d) of the NMSA requires Federal 
agencies to consult with the Office of National Marine Sanctuaries 
whenever their Proposed Activities are likely to destroy, cause the 
loss of, or injure a sanctuary resource. There are five designated NMSs 
and one proposed NMS within the AFTT Study Area (see section 6.1.3 of 
the 2024 AFTT Draft Supplemental EIS/OEIS). Two of these sanctuaries, 
Flower Garden Banks NMS in the Gulf of America and Monitor NMS off of 
North Carolina, do not inform our assessment of impacts to marine 
mammals and their habitat.
    Three NMSs and one proposed NMS within the AFTT Study Area are

[[Page 19910]]

associated with features that inform our assessment of impacts to 
marine mammals and their habitat: Gerry E. Studds Stellwagen Bank NMS, 
Gray's Reef NMS, Florida Keys NMS, and Hudson Canyon Proposed NMS. 
Stellwagen Bank NMS sits at the mouth of Massachusetts Bay, 3 miles 
(mi; 4.8 km) south of Cape Ann, 3 mi (4.8 km) north of Cape Cod and 25 
mi (40.2 km) due east of Boston and provides feeding and nursery 
grounds for marine mammals including NARW, humpback, sei, and fin 
whales. The Stellwagen Bank NMS is within critical habitat for the NARW 
for foraging (Unit 1). Gray's Reef NMS is 19 mi (30.6 km) east of 
Sapelo Island Georgia, in the South Atlantic Bight (the offshore area 
between Cape Hatteras, North Carolina and Cape Canaveral, Florida) and 
is within the designated critical habitat for NARW calving in the 
southeast (Unit 2). Florida Keys NMS protects 2,900 nmi\2\ (9,947 
km\2\) of waters surrounding the Florida Keys, from south of Miami 
westward to encompass the Dry Tortugas, excluding Dry Tortugas National 
Park and supports a resident group of bottlenose dolphin (Florida Bay 
Population BIA). The Office of National Marine Sanctuaries is in the 
process of designating the Hudson Canyon NMS off the coast of New York 
and New Jersey. Hudson Canyon is the largest submarine canyon along the 
U.S. Atlantic coast and is one of the largest in the world. Beginning 
approximately 100 mi (160.9 km) southeast of New York City, the canyon 
extends about 350 mi (563.3 km) seaward, reaches depths of 2-2.5 mi 
(3.2-4.0 km), and is up to 7.5 mi (12.1 km) wide. Hudson Canyon is 
considered an ecological hotspot due to its size and diversity of 
structures, including steep slopes, firm outcrops for invertebrates, 
diverse sediments, flux of nutrients, and areas of upwelling that 
support marine mammals and provides habitat for a range of endangered 
and protected species, including sperm whales.

Unusual Mortality Events

    An Unusual Mortality Event (UME) is defined under section 410(6) of 
the MMPA as a stranding that is unexpected; involves a significant die-
off of any marine mammal population; and demands immediate response. 
Three UMEs with ongoing investigations in the AFTT Study Area that 
inform our analysis are discussed below. The 2022 Maine Pinniped UME 
has closed, and the 2018 Northeast Pinniped UME is non-active and 
pending closure.
North Atlantic Right Whale (2017-Present)
    Beginning in 2017, elevated mortalities in NARW were documented in 
Canada and the United States and necessitated an UME be declared. The 
whales impacted by the UME include dead, injured, and sick individuals, 
who represent more than 20 percent of the population, which is a 
significant impact on an endangered species where deaths are outpacing 
births. Additionally, research demonstrates that only about one third 
of right whale deaths are documented. The preliminary cause of 
mortality, serious injury, and morbidity (sublethal injury and illness) 
in most of these whales is from entanglements or vessel strikes. 
Endangered NARW are approaching extinction. There are approximately 372 
individuals remaining, including fewer than 70 reproductively active 
females. Human impacts continue to threaten the survival of this 
species. The many individual whales involved in the UME are a 
significant setback to the recovery of this endangered species.
    Since 2017, dead, seriously injured, sublethally injured, or ill 
NARW along the United States and Canadian coasts have been documented, 
necessitating a UME declaration and investigation. The leading category 
for the cause of death for this ongoing UME is ``human interaction,'' 
specifically from entanglements or vessel strikes. As of January 2, 
2025, there have been 41 confirmed mortalities (dead, stranded, or 
floating) and 39 seriously injured free-swimming whales for a total of 
80 whales. The UME also considers animals with sublethal injury or 
illness (i.e., ``morbidity''; n = 71) bringing the total number of 
whales in the UME to 151. More information about the NARW UME is 
available online at https://www.fisheries.noaa.gov/national/marine-life-distress/2017-2025-north-atlantic-right-whale-unusual-mortality-event.
Humpback Whale (2017-Present)
    Since January 2016, elevated humpback whale mortalities have 
occurred along the Atlantic coast from Maine to Florida. This event was 
declared a UME in April 2017. Partial or full necropsy examinations 
have been conducted on approximately half of the 244 known cases (as of 
February 6, 2025). Of the whales examined (approximately 90), about 40 
percent had evidence of human interaction either from vessel strike or 
entanglement. While a portion of the whales have shown evidence of pre-
mortem vessel strike, this finding is not consistent across all whales 
examined, and more research is needed. NOAA is consulting with 
researchers that are conducting studies on the humpback whale 
populations, and these efforts may provide information on changes in 
whale distribution and habitat use that could provide additional 
insight into how these vessel interactions occurred. More information 
is available at: https://www.fisheries.noaa.gov/national/marine-life-distress/2016-2025-humpback-whale-unusual-mortality-event-along-atlantic-coast.
Minke Whale (2017-Present)
    Elevated minke whale mortalities detected along the Atlantic coast 
from Maine through South Carolina resulted in the declaration of an on-
going UME in 2017. As of February 10, 2025, a total of 198 minke whales 
have stranded during this UME. Full or partial necropsy examinations 
were conducted on more than 60 percent of the whales. Preliminary 
findings show evidence of human interactions or infectious disease, but 
these findings are not consistent across all of the minke whales 
examined, so more research is needed. More information is available at: 
https://www.fisheries.noaa.gov/national/marine-life-distress/2017-2025-minke-whale-unusual-mortality-event-along-atlantic-coast.
Phocid Seals (2018-2020, 2022)
    Harbor and gray seals have experienced two UMEs since 2018, 
although one was recently closed (2022 Pinniped UME in Maine) and 
closure of the other, described here, is pending. Beginning in July 
2018, elevated numbers of harbor seal and gray seal mortalities 
occurred across Maine, New Hampshire, and Massachusetts. Additionally, 
stranded seals have shown clinical signs as far south as Virginia, 
although not in elevated numbers, therefore the UME investigation 
encompassed all seal strandings from Maine to Virginia. A total of 
3,152 reported strandings (of all species) occurred from July 1, 2018, 
through March 13, 2020. Full or partial necropsy examinations were 
conducted on some of the seals and samples were collected for testing. 
Based on tests conducted thus far, the main pathogen found in the seals 
is phocine distemper virus. NMFS is performing additional testing to 
identify any other factors that may be involved in this UME, which is 
pending closure. Information on this UME is available online at: 
https://www.fisheries.noaa.gov/new-england-mid-atlantic/marine-life-distress/2018-2020-pinniped-unusual-mortality-event-along.

[[Page 19911]]

Deepwater Horizon Oil Spill

    In 2010, the BP-operated Macondo well blowout and explosion aboard 
the Deepwater Horizon drilling rig (also known as the Deepwater Horizon 
explosion, oil spill, and response; hereafter referred to as the DWH 
oil spill) caused oil, natural gas, and other substances to flow into 
the Gulf of America for 87 days before the well was sealed. Total oil 
discharge was estimated at 3.19 million barrels (134 million gallons), 
resulting in the largest marine oil spill in history (DWH Natural 
Resource Damage Assessment (NRDA) Trustees, 2016). In addition, the 
response effort involved extensive application of dispersants at the 
seafloor and at the surface, and controlled burning of oil at the 
surface was also used extensively as a response technique. The oil, 
dispersant, and burn residue compounds present ecological challenges in 
the region.
    At its maximum extent, oil covered over 15,444 mi\2\ (40,000 km\2\) 
of ocean. Cumulatively, over the course of the spill, oil was detected 
on over 43,243 mi\2\ (112,000 km\2\) of ocean. Currents, winds, and 
tides carried these surface oil slicks to shore, fouling more than 
1,304.9 mi (2,100 km) of shoreline, including beaches, bays, estuaries, 
and marshes from eastern Texas to the Florida Panhandle. In addition, 
some lighter oil compounds evaporated from the slicks, exposing air-
breathing organisms like marine mammals to noxious fumes at the sea 
surface.
    DWH oil was found to cause problems with the regulation of stress 
hormone secretion from adrenal cells and kidney cells, which will 
affect an animal's ability to regulate body functions and respond 
appropriately to stressful situations, thus leading to reduced fitness. 
Bottlenose dolphins living in habitats contaminated with DWH oil showed 
signs of adrenal dysfunction, and dead, stranded dolphins from areas 
contaminated with DWH oil had smaller adrenal glands (Schwacke et al., 
2014a; Venn-Watson et al., 2015b). Other factors were ruled out as a 
primary cause for the high prevalence of adverse health effects, 
reproductive failures, and disease in stranded animals. When all of the 
data were considered together, the DWH oil spill was determined to be 
the only reasonable cause for the full suite of observed adverse health 
effects.
    Due to the difficulty of investigating marine mammals in pelagic 
environments and across the entire region impacted by the event, the 
injury assessment focused on health assessments conducted on bottlenose 
dolphins in nearshore habitats and used these populations as case 
studies for extrapolating to coastal and oceanic populations that 
received similar or worse exposure to DWH oil, with appropriate 
adjustments made for differences in behavior, anatomy, physiology, life 
histories, and population dynamics among species. Investigators then 
used a population modeling approach to capture the overlapping and 
synergistic relationships among the metrics for injury, and to quantify 
the entire scope of DWH marine mammal injury to populations into the 
future, expressed as ``lost cetacean years'' due to the DWH oil spill 
(which represents years lost due to premature mortality as well as the 
resultant loss of reproductive output). This approach allowed for 
consideration of long-term impacts resulting from immediate losses and 
reproductive failures in the few years following the spill, as well as 
expected persistent impacts on survival and reproduction for exposed 
animals well into the future (Takeshita et al., 2017; Smith et al., 
2022). For a more detailed overview of the injury quantification for 
these stocks and their post-DWH population trajectory, please see 
Schwacke et al. (2017) and Marques et al. (2023), and for full details 
of the overall injury quantification, see DWH Marine Mammal Injury 
Quantification Team (MMIQT) (2015).
    The results of the quantification exercise for each affected shelf 
and oceanic stock, and for northern and western coastal stocks of 
bottlenose dolphin, are presented in table 15. This is likely a 
conservative estimate of impacts, because: (1) Shelf and oceanic 
species experienced long exposures (up to 90 days) to very high 
concentrations of fresh oil and a diverse suite of response activities, 
while estuarine dolphins were not exposed until later in the spill 
period and to weathered oil products at lower water concentrations; (2) 
oceanic cetaceans dive longer and to deeper depths, and it is possible 
that the types of lung injuries observed in estuarine dolphins may be 
more severe for oceanic cetaceans; and (3) cetaceans in deeper waters 
were exposed to very high concentrations of volatile gas compounds at 
the water's surface near the wellhead. No analysis was performed for 
Fraser's dolphins or killer whales; although they are present in the 
Gulf of America, sightings are rare and there were no historical 
sightings in the oil spill footprint during the surveys used in the 
quantification process. These stocks were likely injured, but no 
information was available on which to base a quantification effort at 
that time.

                                         Table 15--Summary of Modeled Effects of the Deepwater Horizon Oil Spill
                                                                [DWH NRDA Trustees, 2016]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                            Percent of
                                                            Percent of      Percent of      Percent of      population      Percent of
                                                            population      population     females with    with adverse       maximum        Years to
            Common name                     Stock         exposed to oil    killed (95     reproductive   health effects    population     recovery (95
                                                            (95 percent     percent CI)     failure (95     (95 percent    reduction (95   percent CI) *
                                                                CI)                         percent CI)         CI)         percent CI)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rice's whale (formerly Bryde's      Northern Gulf of         48 (23-100)       17 (7-24)      22 (10-31)       18 (7-28)             -22              69
 whale).                             America.
Sperm whale.......................  Northern Gulf of          16 (11-23)         6 (2-8)        7 (3-10)         6 (2-9)              -7              21
                                     America.
Kogia spp.........................  Multiple............       15 (8-29)         5 (2-7)        7 (3-10)         6 (2-9)              -6              11
Beaked whales.....................  Multiple............       12 (7-22)         4 (2-6)         5 (3-8)         4 (2-7)              -6              10
Bottlenose dolphin................  Northern Gulf of           10 (5-10)         3 (1-5)         5 (2-6)         4 (1-6)              -4             N/A
                                     America, Oceanic.
Bottlenose dolphin................  Gulf of America,         82 (55-100)      38 (26-58)      37 (17-53)      30 (11-47)     -50 (32-73)      39 (23-76)
                                     Northern Coastal.

[[Page 19912]]

 
Bottlenose dolphin................  Gulf of America,          23 (16-32)         1 (1-2)       10 (5-15)        8 (3-13)        -5 (3-9)             N/A
                                     Western Coastal.
Shelf dolphins **.................  Multiple............       13 (9-19)         4 (2-6)         6 (3-8)         5 (2-7)              -3             N/A
Clymene dolphin...................  Northern Gulf of            7 (3-15)         2 (1-4)         3 (2-5)         3 (1-4)              -3             N/A
                                     America.
False killer whale................  Northern Gulf of           18 (7-48)         6 (3-9)        8 (4-12)        7 (3-11)              -9              42
                                     America.
Melon-headed whale................  Northern Gulf of           15 (6-36)         5 (2-7)        7 (3-10)         6 (2-9)              -7              29
                                     America.
Pantropical spotted dolphin.......  Northern Gulf of          20 (15-26)        7 (3-10)        9 (4-13)        7 (3-11)              -9              39
                                     America.
Pygmy killer whale................  Northern Gulf of           15 (7-33)         5 (2-8)        7 (3-10)         6 (2-9)              -7              29
                                     America.
Risso's dolphin...................  Northern Gulf of            8 (5-13)         3 (1-4)         3 (2-5)         3 (1-4)              -3             N/A
                                     America.
Rough-toothed dolphin.............  Northern Gulf of         41 (16-100)       14 (6-20)       19 (9-26)       15 (6-23)             -17              54
                                     America.
Short-finned pilot whale..........  Northern Gulf of             6 (4-9)         2 (1-3)        3 (1-40)         2 (1-3)              -3             N/A
                                     America.
Spinner dolphin...................  Northern Gulf of          47 (24-91)       16 (7-23)      21 (10-30)       17 (6-27)             -23             105
                                     America.
Striped dolphin...................  Northern Gulf of           13 (8-22)         5 (2-7)         6 (3-9)         5 (2-8)              -6              14
                                     America.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Table modified from the DWH NRDA Trustees (2016). CI = confidence interval, No CI was calculated for population reduction or years to recovery for
  shelf or oceanic stocks. Marine mammals in the Gulf of America are named in DWH NRDA Trustees (2016) with reference to the formerly named ``Gulf of
  Mexico.'' This Notice refers to these marine mammal stocks as Northern Gulf of America stocks. The geographical location of the stocks remains the
  same.
* It is not possible to calculate years to recovery for stocks with maximum population reductions of less than or equal to 5 percent.
** Shelf dolphins includes Atlantic spotted dolphins and the shelf stock of bottlenose dolphins (20-200 m water depth). These two species were combined
  because the abundance estimate used in population modeling was derived from aerial surveys and the species could not generally be distinguished from
  the air.

    However, a recent study by Frasier et al. (2024), using a widely-
spaced passive acoustic monitoring array, found that of eight groups 
monitored from 2010-2020, seven groups experienced long-term density 
declines, including beaked whales (up to 83 percent), small delphinids 
(up to 43 percent), and sperm whales (up to 31 percent). These measured 
density declines exceed model-predicted changes and do not suggest 
recovery trends for affected species to date (Frasier et al., 2024). 
Population consequences of 15 cetacean taxonomic units in pelagic and 
continental shelf waters (not including killer whales, false killer 
whales, and Fraser's dolphins) were assessed by Marques et al. (2023), 
who found that the DWH oil spill had the greatest population impacts on 
spinner dolphins, striped dolphins, sperm whales, oceanic bottlenose 
dolphins, and Kogia species. The number of lost cetacean years was 
highest for the shelf bottlenose dolphin population (32,584 years) and 
pantropical spotted dolphin population (31,372 years) (Marques et al., 
2023).

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Not all marine mammal species have equal 
hearing capabilities (e.g., Richardson et al., 1995, Wartzok and 
Ketten, 1999, Au and Hastings, 2008). To reflect this, Southall et al. 
(2007), Southall et al. (2019) recommended that marine mammals be 
divided into hearing groups based on directly measured (behavioral or 
auditory evoked potential techniques) or estimated hearing ranges 
(e.g., behavioral response data, anatomical modeling). NMFS (2024) 
generalized hearing ranges were chosen based on the approximately 65-dB 
threshold from the composite audiograms, previous analysis in NMFS 
(2018), and/or data from Southall et al. (2007) and Southall et al. 
(2019). We note that the names of two hearing groups and the 
generalized hearing ranges of all marine mammal hearing groups have 
been recently updated (NMFS, 2024) as reflected below in table 16.

                 Table 16--Marine Mammal Hearing Groups
                              [NMFS, 2024]
------------------------------------------------------------------------
            Hearing group                 Generalized hearing range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen   7 Hz to 36 ** kHz.
 whales).

[[Page 19913]]

 
High-frequency (HF) cetaceans          150 Hz to 160 kHz.
 (dolphins, toothed whales, beaked
 whales, bottlenose whales).
Very High-frequency (VHF) cetaceans    200 Hz to 165 kHz.
 (true porpoises, Kogia, river
 dolphins, Cephalorhynchid,
 Lagenorhynchus cruciger & L.
 australis).
Phocid pinnipeds (PW) (underwater)     40 Hz to 90 kHz.
 (true seals).
Otariid pinnipeds (OW) (underwater)    60 Hz to 68 kHz.
 (sea lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
  composite (i.e., all species within the group), where individual
  species' hearing ranges are typically not as broad. Generalized
  hearing range chosen based on the ~65-dB threshold from composite
  audiogram, previous analysis in NMFS (2018), and/or data from Southall
  et al. (2007) and Southall et al. (2019). Additionally, animals are
  able to detect very loud sounds above and below that ``generalized''
  hearing range.
** The Action Proponents split the LF functional hearing group into LF
  and VLF based on Houser et al., (2024) while NMFS Updated Technical
  Guidance (NMFS, 2024) does not include these data. NMFS is aware these
  data and data collected during a final field season by Houser et al.
  (in prep) have implications for the generalized hearing range for low-
  frequency cetaceans and their weighting function, however, as
  described in the 2024 Updated Technical Guidance, it is premature for
  us to propose any changes to our current Updated Technical Guidance.
  Mysticete hearing data is identified as a special circumstance that
  could merit reevaluating the acoustic criteria for low-frequency
  cetaceans in the 2024 Updated Technical Guidance once the data from
  the final field season is published. Therefore, we anticipate that
  once the data are published, it will likely necessitate updating this
  document (i.e., likely after the data gathered in the summer 2024
  field season and associated analysis are published).

    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2024) for a review of available information.
    The Navy adjusted these hearing groups using data from recent 
hearing measurements in minke whales (Houser et al., 2024). These data 
support separating mysticetes (the LF cetacean marine mammal hearing 
group in table 16) into two hearing groups, which the Navy designates 
as ``very low-frequency (VLF) cetaceans'' and ``low-frequency (LF) 
cetaceans,'' which follows the recommendations of Southall et al. 
(2019a). Within the Navy's adjusted hearing groups, the VLF cetacean 
group contains the larger mysticetes (blue, fin, right, and bowhead 
whales) and the LF cetacean group contains the mysticete species not 
included in the VLF group (e.g., minke, humpback, gray, pygmy right 
whales). Although there have been no direct measurements of hearing 
sensitivity in the larger mysticetes included in Navy's VLF hearing 
group, an audible frequency range of approximately 10 Hz to 30 kHz has 
been estimated from measured vocalization frequencies, observed 
responses to playback of sounds, and anatomical analyses of the 
auditory system. The upper frequency limit of hearing in Navy's LF 
hearing group has been estimated in a minke whale from direct 
measurements of auditory evoked potentials (Houser et al., 2024).

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    This section provides a discussion of the ways in which components 
of the specified activity may impact marine mammals and their habitat. 
The Estimated Take of Marine Mammals section later in this document 
includes a quantitative analysis of the number of individuals that are 
expected to be taken by this activity. The Preliminary Analysis and 
Negligible Impact Determination section considers the content of this 
section, the Estimated Take of Marine Mammals section, and the Proposed 
Mitigation Measures section, to draw conclusions regarding the likely 
impacts of these activities on the reproductive success or survivorship 
of individuals and whether those impacts on individuals are likely to 
adversely affect the species through effects on annual rates of 
recruitment or survival.
    The Action Proponents have requested authorization for the take of 
marine mammals that may occur incidental to training and testing 
activities in the AFTT Study Area. The Action Proponents analyzed 
potential impacts to marine mammals from acoustic and explosive sources 
and from vessel use in the application. NMFS carefully reviewed the 
information provided by the Action Proponents and concurs with their 
synthesis of science, along with independently reviewing applicable 
scientific research and literature and other information to evaluate 
the potential effects of the Action Proponents' activities on marine 
mammals, which are presented in this section (see appendix D in the 
2024 AFTT Draft Supplemental EIS/OEIS for additional information).
    Other potential impacts to marine mammals from training and testing 
activities in the AFTT Study Area were analyzed in the 2024 AFTT Draft 
Supplemental EIS/OEIS, in consultation with NMFS as a cooperating 
agency, and determined to be unlikely to result in marine mammal take. 
Therefore, the Action Proponents have not requested authorization for 
take of marine mammals incidental to other components of their proposed 
Specified Activities, and we agree that incidental take is unlikely to 
occur from those components. In this proposed rule, NMFS analyzes the 
potential effects on marine mammals from the activity components that 
may cause the take of marine mammals: exposure to acoustic or explosive 
stressors including non-impulsive (sonar and other transducers, and 
vibratory pile driving) and impulsive (explosives, impact pile driving, 
and air guns) stressors and vessel movement.
    For the purpose of MMPA incidental take authorizations, NMFS' 
effects assessments serve four primary purposes: (1) to determine 
whether the specified activities would have a negligible impact on the 
affected species or stocks of marine mammals (based on whether it is 
likely that the activities would adversely affect the species or stocks 
through effects on annual rates of recruitment or survival); (2) to 
determine whether the specified activities would have an unmitigable 
adverse impact on the availability of the species or stocks for 
subsistence uses; (3) to prescribe the permissible methods of taking 
(i.e., Level B harassment (behavioral harassment and temporary 
threshold shift (TTS)), Level A harassment (auditory (AUD INJ) and non-
auditory injury), serious injury, or mortality), including 
identification of the number and types of take that could occur by 
harassment, serious injury, or mortality, and to prescribe other means 
of effecting the least practicable adverse impact on the species or 
stocks and their habitat (i.e., mitigation measures); and (4) to 
prescribe requirements pertaining to monitoring and reporting.

[[Page 19914]]

    In this section, NMFS provides a description of the ways marine 
mammals may be generally affected by these activities in the form of 
mortality, physical injury, sensory impairment (permanent and temporary 
threshold shifts and acoustic masking), physiological responses 
(particular stress responses), behavioral disturbance, or habitat 
effects. Explosives and vessel strikes, which have the potential to 
result in incidental take by serious injury and/or mortality, will be 
discussed in more detail in the Estimated Take of Marine Mammals 
section. The Estimated Take of Marine Mammals section also discusses 
how the potential effects on marine mammals from non-impulsive and 
impulsive sources relate to the MMPA definitions of Level A Harassment 
and Level B Harassment, and quantifies those effects that rise to the 
level of a take. The Preliminary Analysis and Negligible Impact 
Determination section assesses whether the proposed authorized take 
would have a negligible impact on the affected species and stocks.

Potential Effects of Underwater Sound on Marine Mammals

    The marine soundscape is comprised of both ambient and 
anthropogenic sounds. Ambient sound is defined as the all-encompassing 
sound in a given place and is usually a composite of sound from many 
sources both near and far (ANSI, 1995). The sound level of an area is 
defined by the total acoustical energy being generated by known and 
unknown sources, which may include physical (e.g., waves, wind, 
precipitation, earthquakes, ice, atmospheric sound), biological (e.g., 
sounds produced by marine mammals, fish, and invertebrates), and 
anthropogenic sound (e.g., vessels, dredging, aircraft, construction).
    The sum of the various natural and anthropogenic sound sources at 
any given location and time--which comprise ``ambient'' or 
``background'' sound--depends not only on the source levels (as 
determined by current weather conditions and levels of biological and 
shipping activity) but also on the ability of sound to propagate 
through the environment. In turn, sound propagation is dependent on the 
spatially and temporally varying properties of the water column and sea 
floor and is frequency-dependent. As a result of the dependence on a 
large number of varying factors, ambient sound levels can be expected 
to vary widely over both coarse and fine spatial and temporal scales. 
Sound levels at a given frequency and location can vary by 10-20 dB 
from day to day (Richardson et al., 1995). The result is that, 
depending on the source type and its intensity, sound from the 
specified activities may be a negligible addition to the local 
environment or could form a distinctive signal that may affect marine 
mammals.
    Anthropogenic sounds cover a broad range of frequencies and sound 
levels and can have a range of highly variable impacts on marine life, 
from none or minor to potentially severe responses, depending on 
received levels, duration of exposure, behavioral context, and various 
other factors. The potential effects of underwater sound from active 
acoustic sources can possibly result in one or more of the following: 
temporary or permanent hearing impairment, other auditory injury, non-
auditory physical or physiological effects, behavioral disturbance, 
stress, and masking (Richardson et al., 1995; Gordon et al., 2004; 
Nowacek et al., 2007; Southall et al., 2007; G[ouml]tz et al., 2009, 
Southall et al., 2019a). The degree of effect is intrinsically related 
to the signal characteristics, received level, distance from the 
source, and duration of the sound exposure. In general, sudden, high-
level sounds can cause auditory injury, as can longer exposures to 
lower level sounds. Temporary or permanent loss of hearing can occur 
after exposure to noise, and occurs almost exclusively for noise within 
an animal's hearing range.
    Richardson et al. (1995) described zones of increasing intensity of 
effect that might be expected to occur, in relation to distance from a 
source and assuming that the signal is within an animal's hearing 
range. First is the area within which the acoustic signal would be 
audible (potentially perceived) to the animal, but not strong enough to 
elicit any overt behavioral or physiological response. The next zone 
corresponds with the area where the signal is audible to the animal and 
of sufficient intensity to elicit behavioral or physiological 
responsiveness. Third is a zone within which, for signals of high 
intensity, the received level is sufficient to potentially cause 
discomfort or non-auditory injury to auditory systems. Overlaying these 
zones to a certain extent is the area within which masking (i.e., when 
a sound interferes with or masks the ability of an animal to detect a 
signal of interest that is above the absolute hearing threshold) may 
occur; the masking zone may be highly variable in size.
    We also describe more severe potential effects (i.e., certain non-
auditory physical or physiological effects). Potential effects from 
impulsive sound sources can range in severity from effects such as 
behavioral disturbance or tactile perception to physical discomfort, 
slight injury of the internal organs and the auditory system, or, in 
the case of explosives, more severe injuries or mortality (Yelverton et 
al., 1973). Non-auditory physiological effects or injuries that 
theoretically might occur in marine mammals exposed to high levels of 
underwater sound or as a secondary effect of extreme behavioral 
responses (e.g., change in dive profile as a result of an avoidance 
response) caused by exposure to sound include neurological effects, 
bubble formation, resonance effects, and other types of organ or non-
auditory injury (Cox et al., 2006; Southall et al., 2007; Zimmer and 
Tyack, 2007; Tal et al., 2015).
Hearing
    Marine mammals have adapted hearing based on their biology and 
habitat: amphibious marine mammals (e.g., pinnipeds that spend time on 
land and underwater) have modified ears that allow them to hear both 
in-air and in-water, while fully aquatic marine mammals (e.g., 
cetaceans that are always underwater) have specialized ear adaptations 
for in-water hearing (Wartzok and Ketten, 1999). These adaptations 
explain the variation in hearing ability and sensitivity among marine 
mammals and have led to the characterization of marine mammal 
functional hearing groups based on those sensitivities: very low-
frequency cetaceans (VLF group: blue, fin, right, and bowhead whales), 
low-frequency cetaceans (LF group: minke, sei, Bryde's, Rice's, 
humpback, gray, and pygmy right whales), high-frequency cetaceans (HF 
group: sperm whales, beaked whales, killer whale, melon-headed whale, 
false/pygmy killer whale, pilot whales, and some dolphin species), very 
high-frequency cetaceans (VHF group: some dolphin species, porpoises, 
Amazon River dolphin, Kogia species, Baiji, and La Plata dolphin), 
sirenians (SI group: manatees, dugongs), otariids and other non-phocid 
marine carnivores in water and in air (OCW and OCA groups: sea lion, 
fur seal, walrus, otter), and phocids in water and in air (PCW and PCA 
groups: true seals) (Southall et al., 2019c). In Phase III, VLF and LF 
cetaceans were part of one, combined LF cetacean hearing group. 
However, as described in the Navy's report ``Criteria and Thresholds 
for U.S. Navy Acoustic and Explosive Effects Analysis (Phase 4)'' (U.S. 
Department of the Navy, 2024), Houser et al. (2024) recently reported 
hearing measurements for minke whales. The Action

[[Page 19915]]

Proponents incorporated these measurements, as well as Southall et al. 
(2019c), into their analysis. They determined that the data support 
dividing mysticetes into two separate hearing groups: VLF and LF 
cetacean, and NMFS concurs (as described further in the Estimated Take 
of Marine Mammals section), that this approach is appropriate for this 
action.
    The hearing sensitivity of marine mammals is also directional, 
meaning the angle between an animal's position and the location of a 
sound source impacts the animal's hearing threshold, thereby impacting 
an animal's ability to perceive the sound emanating from that source. 
This directionality is likely useful for determining the general 
location of a sound, whether for detection of prey, predators, or 
members of the same species, and can be dependent upon the frequency of 
the sound (Accomando et al., 2020; Au and Moore, 1984; Byl et al., 
2016; Byl et al. 2019; Kastelein et al., 2005; Kastelein et al., 2019; 
Popov and Supin, 2009).
Acoustic Signaling
    An acoustic signal refers to the sound waves used to communicate 
underwater, and marine mammals use a variety of acoustic signals for 
socially important functions, such as communicating, as well as 
biologically important functions, such as echolocating (Richardson et 
al., 1995; Wartzok and Ketten, 1999). Acoustic signals used for 
communication are lower frequency (i.e., 20 Hz to 30 kHz) than those 
signals used for echolocation, which are high-frequency (approximately 
10-200 kHz peak frequency) signals used by odontocetes to sense their 
underwater environment. Lower frequency vocalizations used for 
communication may have a specific, prominent fundamental frequency 
(Brady et al., 2021) or have a wide frequency range, depending on the 
functional hearing group and whether the marine mammal is vocalizing 
in-water or in-air. Acoustic signals used for echolocation are high-
frequency, high-energy sounds with patterns and peak frequencies that 
are often species-specific (Baumann-Pickering et al., 2013).
    Marine mammal species typically produce sounds at frequencies 
within their own hearing range, though auditory and vocal ranges do not 
perfectly align (e.g., odontocetes may only hear a portion of the 
frequencies of an echolocation click). Because determining a species 
vocal range is easier than determining a species' hearing range, vocal 
ranges are often used to infer a species' hearing range when species-
specific hearing data are not available (e.g., large whale species).
Hearing Loss and Auditory Injury
    Marine mammals, like all mammals, lose their ability to hear over 
time due to age-related degeneration of auditory pathways and sensory 
cells of the inner ear. This natural, age-related hearing loss is 
distinct from acute noise-induced hearing loss (M[oslash]ller, 2013). 
Noise-induced hearing loss can be temporary (i.e., TTS) or permanent 
(permanent threshold shift, PTS), and higher-level sound exposures are 
more likely to cause PTS or other AUD INJ. For marine mammals, AUD INJ 
is considered to be possible when sound exposures are sufficient to 
produce 40 dB of TTS measured approximately 4 minutes after exposure 
(U.S. Department of the Navy, 2024). Numerous studies have directly 
examined noise-induced hearing loss in marine mammals by measuring an 
animal's hearing threshold before and after exposure to intense sounds. 
The difference between the post-exposure and pre-exposure hearing 
thresholds is then used to determine the amount of TTS (in dB) that was 
produced as a result of the sound exposure (see appendix D of the 2024 
AFTT Draft Supplemental EIS/OEIS for additional details). The Navy used 
these studies to generate exposure functions, which are predictions of 
the onset of TTS or PTS based on sound frequency, level, and type 
(continuous or impulsive), for each marine mammal functional hearing 
group (U.S. Department of the Navy, 2024).
    TTS can last from minutes or hours to days (i.e., there is recovery 
back to baseline/pre-exposure hearing threshold), can occur within a 
specific frequency range (i.e., an animal might only have a temporary 
loss of hearing sensitivity within a limited frequency band of its 
auditory range), and can be of varying amounts (e.g., an animal's 
hearing sensitivity might be reduced by only 6 dB or reduced by 30 dB). 
While there is no simple functional relationship between TTS and PTS or 
other AUD INJ (e.g., neural degeneration), as TTS increases, the 
likelihood that additional exposure to increased sound pressure level 
(SPL) or duration will result in PTS or other injury also increases 
(see the 2024 AFTT Draft Supplemental EIS/OEIS for additional 
discussion). Exposure thresholds for the occurrence of AUD INJ, which 
include the potential for PTS, as well as situations when AUD INJ 
occurs without PTS, can therefore be defined based on a specific amount 
of TTS; that is, although an exposure has been shown to produce only 
TTS, we assume that any additional exposure may result in some AUD INJ. 
The specific upper limit of TTS is based on experimental data showing 
amounts of TTS that have not resulted in AUD INJ. In other words, we do 
not need to know the exact functional relationship between TTS and AUD 
INJ, we only need to know the upper limit for TTS before some AUD INJ 
is possible. In severe cases of AUD INJ, there can be total or partial 
deafness, while in most cases the animal has an impaired ability to 
hear sounds in specific frequency ranges (Kryter, 1985).
    The following physiological mechanisms are thought to play a role 
in inducing auditory threshold shift: effects to sensory hair cells in 
the inner ear that reduce their sensitivity; modification of the 
chemical environment within the sensory cells; residual muscular 
activity in the middle ear; displacement of certain inner ear 
membranes; increased blood flow; and post-stimulatory reduction in both 
efferent and sensory neural output (Southall et al., 2007). The 
amplitude, duration, frequency, temporal pattern, and energy 
distribution of sound exposure all can affect the amount of associated 
threshold shift and the frequency range in which it occurs. Generally, 
the amount of threshold shift, and the time needed to recover from the 
effect, increase as amplitude and duration of sound exposure increases. 
Human non-impulsive noise exposure guidelines are based on the 
assumption that exposures of equal energy (the same SEL) produce equal 
amounts of hearing impairment regardless of how the sound energy is 
distributed in time (NIOSH, 1998). Previous marine mammal TTS studies 
have also generally supported this equal energy relationship (Southall 
et al., 2007). SEL is used to predict TTS in marine mammals and is 
considered a good predictor of TTS for shorter duration exposures than 
longer duration exposures. The amount of TTS increases with exposure 
SPL and duration, and is correlated with SEL, but duration of the 
exposure has a more significant effect on TTS than would be predicted 
based on SEL alone (e.g., Finneran et al., 2010b; Kastak et al., 2007; 
Kastak et al., 2005; Kastelein et al., 2014a; Mooney et al., 2009a; 
Popov et al., 2014; Gransier and Kastelein, 2024). These studies 
highlight the inherent complexity of predicting TTS onset in marine 
mammals, as well as the importance of considering exposure duration 
when assessing potential impacts.
    Generally, TTS increases with SEL in a non-linear fashion, where 
lower SEL exposures will elicit a steady rate of TTS increase while 
higher SEL

[[Page 19916]]

exposures will either increase TTS more rapidly or plateau (Finneran, 
2015; U.S. Department of the Navy, 2024). Additionally, with sound 
exposures of equal energy, those that had lower SPL with longer 
duration were found to induce TTS onset at lower levels than those of 
higher SPL and shorter duration. Less threshold shift will occur from 
intermittent sounds than from a continuous exposure with the same 
energy (some recovery can occur between intermittent exposures) (Kryter 
et al., 1966; Ward, 1997; Mooney et al., 2009a, 2009b; Finneran et al., 
2010; Kastelein et al., 2014; Kastelein et al., 2015). For example, one 
short higher SPL sound exposure may induce the same impairment as one 
longer lower SPL sound, which in turn may cause more impairment than a 
series of several intermittent softer sounds with the same total energy 
(Ward, 1997). Additionally, though TTS is temporary, very prolonged or 
repeated exposure to sound strong enough to elicit TTS, or shorter-term 
exposure to sound levels well above the TTS threshold, can cause AUD 
INJ, at least in terrestrial mammals (Kryter, 1985; Lonsbury-Martin et 
al., 1987).
    Although TTS increases non-linearly in marine mammals, recovery 
from TTS typically occurs in a linear fashion with the logarithm of 
time (Finneran, 2015; Finneran et al., 2010a; Finneran et al., 2010b; 
Finneran and Schlundt, 2013; Kastelein et al., 2012a; Kastelein et al., 
2012b; Kastelein et al., 2013a; Kastelein et al., 2014a; Kastelein et 
al., 2014b; Kastelein et al., 2014c; Popov et al., 2014; Popov et al., 
2013; Popov et al., 2011; Muslow et al., 2023; Finneran et al., 2023). 
Considerable variation has been measured in individuals of the same 
species in both the amount of TTS incurred from similar SELs (Kastelein 
et al., 2012a; Popov et al., 2013) and the time-to-recovery from TTS 
(Finneran, 2015; Kastelein et al., 2019e). Many of these studies relied 
on continuous sound exposures, but intermittent, impulsive sound 
exposures have also been tested. The sound resulting from an explosive 
detonation is considered an impulsive sound, but no direct measurements 
of hearing loss from exposure to explosive sources have been made. Few 
studies (Finneran et al., 2002; Lucke et al., 2009; Sills et al., 2020; 
Muslow et al., 2023) using impulsive sounds have produced enough TTS to 
make predictions about hearing loss due to this source type (see U.S. 
Department of the Navy, 2024a). In general, predictions of TTS based on 
SEL for this type of sound exposure are likely to overestimate TTS 
because some recovery from TTS may occur in the quiet periods between 
impulsive sounds--especially when the duty cycle is low. Peak SPL 
(unweighted) is also used to predict TTS due to impulsive sounds 
(Southall et al., 2007; Southall et al., 2019c; U.S. Department of the 
Navy, 2024a).
    In some cases, intense noise exposures have caused AUD INJ (e.g., 
loss of cochlear neuron synapses), despite thresholds eventually 
returning to normal; i.e., it is possible to have AUD INJ without a 
resulting PTS (e.g., Kujawa and Liberman, 2006, 2009; Kujawa, 2010; 
Fernandez et al., 2015; Ryan et al., 2016; Houser, 2021). In these 
situations, however, threshold shifts were 30-50 dB measured 24 hours 
after the exposure; i.e., there is no evidence that an exposure 
resulting in less than 40 dB TTS measured a few minutes after exposure 
can produce AUD INJ. Therefore, an exposure producing 40 dB of TTS, 
measured a few minutes after exposure, can also be used as an upper 
limit to prevent AUD INJ; i.e., it is assumed that exposures beyond 
those capable of causing 40 dB of TTS have the potential to result in 
INJ (which may or may not result in PTS).
    Irreparable damage to the inner or outer cochlear hair cells may 
cause PTS; however, other mechanisms are also involved, such as 
exceeding the elastic limits of certain tissues and membranes in the 
middle and inner ears and resultant changes in the chemical composition 
of the inner ear fluids (Southall et al., 2007). When AUD INJ occurs, 
there is physical damage to the sound receptors in the ear, whereas TTS 
represents primarily tissue fatigue and is reversible (Southall et al., 
2007). AUD INJ is permanent (i.e., there is incomplete recovery back to 
baseline/pre-exposure levels) but also can occur in a specific 
frequency range and amount as mentioned above for TTS. In addition, 
other investigators have suggested that TTS is within the normal bounds 
of physiological variability and tolerance and does not represent 
physical injury (e.g., Ward, 1997). Therefore, NMFS does not consider 
less than 40 dB of TTS to constitute AUD INJ. The NMFS Acoustic Updated 
Technical Guidance (NMFS, 2024), which was used in the assessment of 
effects for this rule, compiled, interpreted, and synthesized the best 
available scientific information for noise-induced hearing effects for 
marine mammals to derive updated thresholds for assessing the impacts 
of noise on marine mammal hearing.
    While many studies have examined noise-induced hearing loss in 
marine mammals (see Finneran (2015) and Southall et al. (2019a) for 
summaries), published data on the onset of TTS for cetaceans are 
limited to the captive bottlenose dolphin, beluga, harbor porpoise, and 
Yangtze finless porpoise, and for pinnipeds in water, measurements of 
TTS are limited to harbor seals, elephant seals, California sea lions, 
and bearded seals. These studies examine hearing thresholds measured in 
marine mammals before and after exposure to intense sounds, which can 
then be used to determine the amount of threshold shift at various 
post-exposure times. NMFS has reviewed the available studies, which are 
summarized below (see also the 2024 AFTT Draft Supplemental EIS/OEIS 
which includes additional discussion on TTS studies related to sonar 
and other transducers).
     The method used to test hearing may affect the resulting 
amount of measured TTS, with neurophysiological measures producing 
larger amounts of TTS compared to psychophysical measures (Finneran et 
al., 2007; Finneran, 2015; Finneran et al., 2023).
     The amount of TTS varies with the hearing test frequency. 
As the exposure SPL increases, the frequency at which the maximum TTS 
occurs also increases (Kastelein et al., 2014b). For high-level 
exposures, the maximum TTS typically occurs one-half to one octave 
above the exposure frequency (Finneran et al., 2007; Mooney et al., 
2009a; Nachtigall et al., 2004; Popov et al., 2011; Popov et al., 2013; 
Schlundt et al., 2000). The overall spread of TTS from tonal exposures 
can therefore extend over a large frequency range (i.e., narrowband 
exposures can produce broadband (greater than one octave) TTS).
     The amount of TTS increases with exposure SPL and duration 
and is correlated with SEL, especially if the range of exposure 
durations is relatively small (Kastak et al., 2007; Kastelein et al., 
2014b; Popov et al., 2014). As the exposure duration increases, 
however, the relationship between TTS and SEL begins to break down. 
Specifically, duration has a more significant effect on TTS than would 
be predicted on the basis of SEL alone (Finneran et al., 2010a; Kastak 
et al., 2005; Mooney et al., 2009a). This means if two exposures have 
the same SEL but different durations, the exposure with the longer 
duration (thus lower SPL) will tend to produce more TTS than the 
exposure with the higher SPL and shorter duration. In most acoustic 
impact assessments, the scenarios of interest involve shorter duration 
exposures than the marine mammal experimental data from which impact 
thresholds are derived; therefore, use of SEL tends to

[[Page 19917]]

over-estimate the amount of TTS. Despite this, SEL continues to be used 
in many situations because it is relatively simple, more accurate than 
SPL alone, and lends itself easily to scenarios involving multiple 
exposures with different SPL (Finneran, 2015).
     Gradual increases of TTS may not be directly observable 
with increasing exposure levels, before the onset of PTS (Reichmuth et 
al., 2019). Similarly, PTS can occur without measurable behavioral 
modifications (Reichmuth et al., 2019).
     The amount of TTS depends on the exposure frequency. 
Sounds at low frequencies, well below the region of best sensitivity, 
are less hazardous than those at higher frequencies, near the region of 
best sensitivity (Finneran and Schlundt, 2013). The onset of TTS--
defined as the exposure level necessary to produce 6 dB of TTS (i.e., 
clearly above the typical variation in threshold measurements)--also 
varies with exposure frequency. At the low frequency end of a species' 
hearing curve, onset-TTS exposure levels are higher compared to those 
in the region of best sensitivity.
     TTS can accumulate across multiple exposures, but the 
resulting TTS will be less than the TTS from a single, continuous 
exposure with the same SEL (Finneran et al., 2010a; Kastelein et al., 
2014b; Kastelein et al., 2015b; Mooney et al., 2009b). This means that 
TTS predictions based on the total, cumulative SEL will overestimate 
the amount of TTS from intermittent exposures such as sonars and 
impulsive sources.
     The amount of observed TTS tends to decrease with 
increasing time following the exposure; however, the relationship is 
not monotonic (i.e., increasing exposure does not always increase TTS). 
The time required for complete recovery of hearing depends on the 
magnitude of the initial shift; for relatively small shifts recovery 
may be complete in a few minutes, while large shifts (e.g., 
approximately 40 dB) may require several days for recovery. Under many 
circumstances TTS recovers linearly with the logarithm of time 
(Finneran et al., 2010a, 2010b; Finneran and Schlundt, 2013; Kastelein 
et al., 2012a; Kastelein et al., 2012b; Kastelein et al., 2013a; 
Kastelein et al., 2014b; Kastelein et al., 2014c; Popov et al., 2011; 
Popov et al., 2013; Popov et al., 2014). This means that for each 
doubling of recovery time, the amount of TTS will decrease by the same 
amount (e.g., 6 dB recovery per doubling of time).
    Nachtigall et al. (2018) and Finneran (2018) describe the 
measurements of hearing sensitivity of multiple odontocete species 
(bottlenose dolphin, harbor porpoise, beluga, and false killer whale) 
when a relatively loud sound was preceded by a warning sound. These 
captive animals were shown to reduce hearing sensitivity when warned of 
an impending intense sound. Based on these experimental observations of 
captive animals, the authors suggest that wild animals may dampen their 
hearing during prolonged exposures or if conditioned to anticipate 
intense sounds. Finneran (2018) recommends further investigation of the 
mechanisms of hearing sensitivity reduction in order to understand the 
implications for interpretation of existing TTS data obtained from 
captive animals, notably for considering TTS due to short duration, 
unpredictable exposures.
    Marine mammal hearing plays a critical role in communication with 
conspecifics and in interpretation of environmental cues for purposes 
such as predator avoidance and prey capture. Depending on the degree 
(elevation of threshold in dB), duration (i.e., recovery time), and 
frequency range of TTS, and the context in which it is experienced, TTS 
can have effects on marine mammals ranging from discountable to serious 
similar to those discussed in auditory masking, below. For example, a 
marine mammal may be able to readily compensate for a brief, relatively 
small amount of TTS in a non-critical frequency range that takes place 
during a time where ambient noise is lower and there are not as many 
competing sounds present. Alternatively, a larger amount and longer 
duration of TTS sustained during a time when communication is critical 
for successful mother/calf interactions could have more serious impacts 
if it were in the same frequency band as the necessary vocalizations 
and of a severity that impeded communication. The fact that animals 
exposed to high levels of sound that would be expected to result in 
this physiological response would also be expected to have behavioral 
responses of a comparatively more severe or sustained nature is 
potentially more significant than the simple existence of a TTS. 
However, it is important to note that TTS could occur due to longer 
exposures to sound at lower levels so that a behavioral response may 
not be elicited.
    Depending on the degree and frequency range, the effects of AUD INJ 
on an animal could also range in severity, although it is considered 
generally more serious than TTS because it is a permanent condition 
(Reichmuth et al., 2019). Of note, reduced hearing sensitivity as a 
simple function of aging has been observed in marine mammals, as well 
as humans and other taxa (Southall et al., 2007), so we can infer that 
strategies exist for coping with this condition to some degree, though 
likely not without some cost to the animal.
    As the amount of research on hearing sensitivity has grown, so, 
too, has the understanding that marine mammals may be able to self-
mitigate, or protect, against noise-induced hearing loss. An animal may 
learn to reduce or suppress their hearing sensitivity when warned of an 
impending intense sound exposure, or if the duty cycle of the sound 
source is predictable (Finneran, 2018; Finneran et al., 2024; 
Nachtigall and Supin, 2013, 2014, 2015; Nachtigall et al., 2015; 
Nachtigall et al., 2016a, 2018; Nachtigall et al., 2016b). This has 
been shown with several species, including the false killer whale 
(Nachtigall and Supin, 2013), bottlenose dolphin (Finneran, 2018; 
Nachtigall and Supin, 2014, 2015; Nachtigall et al., 2016b), beluga 
whale (Nachtigall et al., 2015), and harbor porpoise (Nachtigall et 
al., 2016a). Additionally, Finneran et al. (2023) and Finneran et al. 
(2024) found that odontocetes that had participated in TTS experiments 
in the past could have learned from that experience and subsequently 
protected their hearing during new sound exposure experiments.
Behavioral Responses
    Behavioral responses to sound are highly variable and context-
specific (Nowacek et al., 2007; Southall et al., 2007; Southall et al., 
2019). Many different variables can influence an animal's perception of 
and response to (nature and magnitude) an acoustic event. An animal's 
prior experience with a sound or sound source affects whether it is 
less likely (habituation, self-mitigation) or more likely 
(sensitization) to respond to certain sounds in the future (animals can 
also be innately predisposed to respond to certain sounds in certain 
ways) (Southall et al., 2007; Southall et al., 2016; Finneran, 2018; 
Finneran et al., 2024; Nachtigall & Supin, 2013, 2014, 2015; Nachtigall 
et al., 2015; Nachtigall et al., 2016a, 2018; Nachtigall et al., 
2016b). Related to the sound itself, the perceived proximity of the 
sound, bearing of the sound (approaching vs. retreating), the 
similarity of a sound to biologically relevant sounds in the animal's 
environment (i.e., calls of predators, prey, or conspecifics), 
familiarity of the sound, and navigational constraints may affect the 
way an animal responds to the sound (Ellison et al., 2011; Southall et 
al.,

[[Page 19918]]

2007, DeRuiter et al., 2013, Southall et al., 2021; Wartzok et al., 
2003). Individuals (of different age, gender, reproductive status, 
etc.) among most populations will have variable hearing capabilities, 
and differing behavioral sensitivities to sounds that will be affected 
by prior conditioning, experience, and current activities of those 
individuals. Southall et al. (2007) and Southall et al. (2021) have 
developed and subsequently refined methods developed to categorize and 
assess the severity of acute behavioral responses, considering impacts 
to individuals that may consequently impact populations. Often, 
specific acoustic features of the sound and contextual variables (i.e., 
proximity, duration, or recurrence of the sound or the current behavior 
that the marine mammal is engaged in or its prior experience), as well 
as entirely separate factors such as the physical presence of a nearby 
vessel, may be more relevant to the animal's response than the received 
level alone.
    Studies by DeRuiter et al. (2012) indicate that variability of 
responses to acoustic stimuli depends not only on the species receiving 
the sound and the sound source, but also on the social, behavioral, or 
environmental contexts of exposure. Another study by DeRuiter et al. 
(2013) examined behavioral responses of goose-beaked whales to MF sonar 
and found that whales responded strongly at low received levels (89-127 
dB re 1 [micro]Pa) by ceasing normal fluking and echolocation, swimming 
rapidly away, and extending both dive duration and subsequent non-
foraging intervals when the sound source was 2.1-5.9 mi (3.4-9.5 km) 
away. Importantly, this study also showed that whales exposed to a 
similar range of received levels (78-106 dB re 1 [micro]Pa) from 
distant sonar exercises 73.3 mi (118 km away) did not elicit such 
responses, suggesting that context may moderate responses.
    Ellison et al. (2012) outlined an approach to assessing the effects 
of sound on marine mammals that incorporates contextual-based factors. 
The authors recommend considering not just the received level of sound, 
but also the activity the animal is engaged in at the time the sound is 
received, the nature and novelty of the sound (i.e., is this a new 
sound from the animal's perspective), and the distance between the 
sound source and the animal. They submit that this ``exposure 
context,'' as described, greatly influences the type of behavioral 
response exhibited by the animal. Forney et al. (2017) also point out 
that an apparent lack of response (e.g., no displacement or avoidance 
of a sound source) may not necessarily mean there is no cost to the 
individual or population, as some resources or habitats may be of such 
high value that animals may choose to stay, even when experiencing 
stress or hearing loss. Forney et al. (2017) recommend considering both 
the costs of remaining in an area of noise exposure such as TTS, PTS, 
or masking, which could lead to an increased risk of predation or other 
threats or a decreased capability to forage, and the costs of 
displacement, including potential increased risk of vessel strike, 
increased risks of predation or competition for resources, or decreased 
habitat suitable for foraging, resting, or socializing. This sort of 
contextual information is challenging to predict with accuracy for 
ongoing activities that occur over large spatial and temporal expanses. 
However, distance is one contextual factor for which data exist to 
quantitatively inform a take estimate, and the method for predicting 
Level B harassment in this rule does consider distance to the source. 
Other factors are often considered qualitatively in the analysis of the 
likely consequences of sound exposure, where supporting information is 
available.
    Friedlaender et al. (2016) provided the first integration of direct 
measures of prey distribution and density variables incorporated into 
across-individual analyses of behavior responses of blue whales to 
sonar, and demonstrated a five-fold increase in the ability to quantify 
variability in blue whale diving behavior. These results illustrate 
that responses evaluated without such measurements for foraging animals 
may be misleading, which again illustrates the context-dependent nature 
of the probability of response.
    Exposure of marine mammals to sound sources can result in, but is 
not limited to, no response or any of the following observable 
responses: increased alertness; orientation or attraction to a sound 
source; vocal modifications; cessation of feeding; cessation of social 
interaction; alteration of movement or diving behavior; habitat 
abandonment (temporary or permanent); and, in severe cases, panic, 
flight, stampede, or stranding, potentially resulting in death 
(Southall et al., 2007). A review of marine mammal responses to 
anthropogenic sound was first conducted by Richardson (1995). More 
recent reviews (Nowacek et al., 2007; DeRuiter et al., 2012 and 2013; 
Ellison et al., 2012; Gomez et al., 2016) address studies conducted 
since 1995 and focused on observations where the received sound level 
of the exposed marine mammal(s) was known or could be estimated. Gomez 
et al. (2016) conducted a review of the literature considering the 
contextual information of exposure in addition to received level and 
found that higher received levels were not always associated with more 
severe behavioral responses and vice versa. Southall et al. (2016) 
state that results demonstrate that some individuals of different 
species display clear yet varied responses, some of which have negative 
implications, while others appear to tolerate high levels, and that 
responses may not be fully predictable with simple acoustic exposure 
metrics (e.g., received sound level). Rather, the authors state that 
differences among species and individuals along with contextual aspects 
of exposure (e.g., behavioral state) appear to affect response 
probability (Southall et al., 2019). The following subsections provide 
examples of behavioral responses to stressors that provide an idea of 
the variability in responses that would be expected given the 
differential sensitivities of marine mammal species to sound and the 
wide range of potential acoustic sources to which a marine mammal may 
be exposed. Behavioral responses that could occur for a given sound 
exposure should be determined from the literature that is available for 
each species (see section D.6.5 (Behavioral Reactions) of the 2024 AFTT 
Draft Supplemental EIS/OEIS for a comprehensive list of behavioral 
studies and species-specific findings), or extrapolated from closely 
related species when no information exists, along with contextual 
factors.
Responses Due to Sonar and Other Transducers--
    Mysticetes responses to sonar and other duty-cycled tonal sounds 
are dependent upon the characteristics of the signal, behavioral state 
of the animal, sensitivity and previous experience of an individual, 
and other contextual factors including distance of the source, movement 
of the source, physical presence of vessels, time of year, and 
geographic location (Goldbogen et al., 2013; Harris et al., 2019a; 
Harris et al., 2015; Martin et al., 2015; Sivle et al., 2015b). For 
example, a behavioral response study (BRS) in Southern California 
demonstrated that individual behavioral state was critically important 
in determining response of blue whales to Navy sonar. In this BRS, some 
blue whales engaged in deep (greater than 164 ft (50 m)) feeding 
behavior had greater dive responses than those in shallow feeding or 
non-feeding conditions, while some blue whales that were engaged in 
shallow feeding behavior demonstrated

[[Page 19919]]

no clear changes in diving or movement even when received levels were 
high (approximately 160 dB re 1 [micro]Pa) from exposures to 3-4 kHz 
sonar signals, while others showed a clear response at exposures at 
lower received level of sonar and pseudorandom noise (Goldbogen et al., 
2013). Generally, behavioral responses were brief and of low to 
moderate severity, and the whales returned to baseline behavior shortly 
after the end of the acoustic exposure (DeRuiter et al., 2017; 
Goldbogen et al., 2013; Southall et al., 2019c). To better understand 
the context to these behavioral responses, Friedlaender et al. (2016) 
mapped the prey field of the deep-diving blue whales and found that the 
response to sound was more apparent for individuals engaged in feeding 
than those that were not. The probability of a moderate behavioral 
response increased when the source was closer for these foraging blue 
whales, although there was a high degree of uncertainty in that 
relationship (Southall et al., 2019b). In the same BRS, none of the 
tagged fin whales demonstrated more than a brief or minor response 
regardless of their behavioral state (Harris et al., 2019a). The fin 
whales were exposed to both mid-frequency simulated sonar and 
pseudorandom noise of similar frequency, duration, and source level. 
They were less sensitive to disturbance than blue whales, with no 
significant differences in response between behavioral states or signal 
types. The authors rated responses as low-to-moderate severity with no 
negative impact to foraging success (Southall et al., 2023).
    Similarly, while the rates of foraging lunges decrease in humpback 
whales due to sonar exposure, there was variability in the response 
across individuals, with one animal ceasing to forage completely and 
another animal starting to forage during the exposure (Sivle et al., 
2016). In addition, almost half of the animals that exhibited avoidance 
behavior were foraging before the exposure, but the others were not; 
the animals that exhibited avoidance behavior while not feeding 
responded at a slightly lower received level and greater distance than 
those that were feeding (Wensveen et al., 2017). These findings 
indicate that the behavioral state of the animal plays a role in the 
type and severity of a behavioral response. Henderson et al. (2019) 
examined tagged humpback whale dive and movement behavior, including 
individuals incidentally exposed to Navy sonar during training 
activities, at the Pacific Missile Range Facility off Kaua'i, Hawaii. 
Tracking data showed that, regardless of exposure to sonar, individual 
humpbacks spent limited time, no more than a few days, in the vicinity 
of Kaua'i. Potential behavioral responses due to sonar exposure were 
limited and may have been influenced by breeding and social behaviors. 
Martin et al. (2015) found that the density of calling minke whales was 
reduced during periods of Navy training involving sonar relative to the 
periods before training began and increased again in the days following 
the completion of training activities. The responses of individual 
whales could not be assessed, so in this case it is unknown whether the 
decrease in calling animals indicated that the animals left the range 
or simply ceased calling. Harris et al. (2019b) utilized acoustically 
generated minke whale tracks to statistically demonstrate changes in 
the spatial distribution of minke whale acoustic presence before, 
during, and after surface ship MFAS training. The spatial distribution 
of probability of acoustic presence was different in the ``during'' 
phase compared to the ``before'' phase, and the probability of presence 
at the center of ship activity during MFAS training was close to zero 
for both years. The ``after'' phases for both years retained lower 
probabilities of presence suggesting the return to baseline conditions 
may take more than five days. The results show a clear spatial 
redistribution of calling minke whales during surface ship MFAS 
training, however a limitation of passive acoustic monitoring is that 
one cannot conclude if the whales moved away, went silent, or a 
combination of the two.
    Building on this work, Durbach et al. (2021) used the same data and 
determined that individual minke whales tended to be in either a fast 
or slow movement behavior state while on the missile range, where 
whales tended to be in the slow state in baseline or before periods but 
transitioned into the fast state with more directed movement during 
sonar exposures. They also moved away from the area of sonar activity 
on the range, either to the north or east depending on where the 
activity was located; this explains the spatial redistribution found by 
Harris et al. (2019b). Minke whales were also more likely to stop 
calling when in the fast state, regardless of sonar activity, or when 
in the slow state during sonar activity (Durbach et al., 2021). 
Similarly, minke whale detections were reduced or ceased altogether 
during periods of sonar use off Jacksonville, Florida, (Norris et al., 
2012; Simeone et al., 2015; U.S. Department of the Navy, 2013), 
especially with an increased ping rate (Charif et al., 2015).
    Odontocetes have varied, context-dependent behavioral responses to 
sonar and other transducers. Much of the research on odontocetes has 
been focused on understanding the impacts of sonar and other 
transducers on beaked whales because they were hypothesized to be more 
susceptible to behavioral disturbance after several strandings of 
beaked whales in which military MFAS was identified as a contributing 
factor (see Stranding and Mortality section). Subsequent BRSs have 
shown beaked whales are likely more sensitive to disturbance than most 
other cetaceans. Many species of odontocetes have been studied during 
BRSs, including Blainville's beaked whale, goose-beaked whale, Baird's 
beaked whale, northern bottlenose whale, harbor porpoise, pilot whale, 
killer whale, sperm whale, false killer whale, melon-headed whale, 
bottlenose dolphin, rough-toothed dolphin, Risso's dolphin, Pacific 
white-sided dolphin, and Commerson's dolphin. Observed responses by 
Blainville's beaked whales, goose-beaked whales, Baird's beaked whales, 
and northern bottlenose whales (the largest of the beaked whales), to 
mid-frequency sonar sounds include cessation of clicking, decline in 
group vocal periods, termination of foraging dives, changes in 
direction to avoid the sound source, slower ascent rates to the 
surface, longer deep and shallow dive durations, and other unusual dive 
behaviors (DeRuiter et al., 2013b; Hewitt et al., 2022; Jacobson et 
al., 2022; McCarthy et al., 2011; Miller et al., 2015; Moretti et al., 
2014; Southall et al., 2011; Stimpert et al., 2014; Tyack et al., 
2011).
    During a BRS in Southern California, a tagged Baird's beaked whale 
exposed to simulated MFA sonar within 3 km increased swim speed and 
modified its dive behavior (Stimpert et al., 2014). One goose-beaked 
whale was also incidentally exposed to real Navy sonar located over 
62.1 mi (100 km) away in addition to the source used in the controlled 
exposure study, and the authors did not detect similar responses at 
comparable received levels. Received levels from the MFA sonar signals 
from the controlled (2.1 to 5.9 mi (3.4 to 9.5 km)) exposures were 
calculated as 84-144 dB re 1 [mu]Pa, and incidental (73.3 mi (118 km)) 
exposures were calculated as 78-106 dB re 1 [mu]Pa, indicating that 
context of the exposures (e.g., source proximity, controlled source 
ramp-up) may have been a significant factor in the responses to the 
simulated sonars (DeRuiter et al., 2013b).

[[Page 19920]]

    Long-term tagging work during the same BRS demonstrated that the 
longer duration dives considered a behavioral response by DeRuiter et 
al. (2013b) fell within the normal range of dive durations found for 
eight tagged goose-beaked whales on the Southern California Offshore 
Range (Schorr et al., 2014). However, the longer inter-deep dive 
intervals found by DeRuiter et al. (2013b), which were among the 
longest found by Schorr et al. (2014) and Falcone et al. (2017), may 
indicate a response to sonar. Williams et al. (2017) note that during 
normal deep dives or during fast swim speeds, beaked whales and other 
marine mammals use strategies to reduce their stroke rates (e.g., 
leaping, wave surfing when swimming, interspersing glides between bouts 
of stroking when diving). The authors determined that in the post-
exposure dives by the tagged goose-beaked whales described in DeRuiter 
et al. (2013b), the whales ceased gliding and swam with almost 
continuous strokes. This change in swim behavior was calculated to 
increase metabolic costs about 30.5 percent and increase the amount of 
energy expending on fast swim speeds from 27-59 percent of their 
overall energy budget. This repartitioning of energy was detected in 
the model up to 1.7 hours after the single sonar exposure. Therefore, 
while the overall post-exposure dive durations were similar, the 
metabolic energy calculated by Williams et al. (2017) was higher. 
However, Southall et al. (2019a) found that prey availability was 
higher in the western area of the Southern California Offshore Range 
where goose-beaked whales preferentially occurred, while prey resources 
were lower in the eastern area and moderate in the area just north of 
the Range. This high prey availability may indicate that goose-beaked 
whales need fewer foraging dives to meet energy requirements than would 
be needed in another area with fewer resources.
    During a BRS in Norway, northern bottlenose whales avoided a sonar 
sound source over a wide range of distances (0.5 to 17.4 mi (0.8 to 28 
km)) and estimated avoidance thresholds ranging from received SPLs of 
117 to 126 dB re 1 [mu]Pa. The behavioral response characteristics and 
avoidance thresholds were comparable to those previously observed in 
beaked whale studies; however, researchers did not observe an effect of 
distance on behavioral response and found that onset and intensity of 
behavioral response were better predicted by received SPL. There was 
one instance where an individual northern bottlenose whale approached 
the vessel, circled the sound source (source level was only 122 dB re 1 
[mu]Pa), and resumed foraging after the exposure. Conversely, one 
northern bottlenose whale exposed to a sonar source was documented 
performing the longest and deepest dive on record for the species, and 
continued swimming away from the source for more than 7 hours (Miller 
et al., 2015; Siegal et al., 2022; Wensveen et al., 2019).
    Research on Blainville's beaked whales at the Atlantic Undersea 
Test and Evaluation Center (AUTEC) range has shown that individuals 
move off-range during sonar use, only returning after the cessation of 
sonar transmission (Boyd et al., 2009; Henderson et al., 2015; Jones-
Todd et al., 2021; Manzano-Roth et al., 2022; Manzano-Roth et al., 
2016; McCarthy et al., 2011; Tyack et al., 2011). Five Blainville's 
beaked whales estimated to be within 1.2 to 18 mi (2 to 29 km) of the 
AUTEC range at the onset of active sonar were displaced a maximum of 
17.4 to 42.3 mi (28 to 68 km) after moving away from the range, 
although one individual did approach the range during active sonar use. 
Researchers found a decline in deep dives at the onset of the training 
and an increase in time spent on foraging dives as whales moved away 
from the range. Predicted received levels at which presumed responses 
were observed were comparable to those previously observed in beaked 
whale studies. Acoustic data indicated that vocal periods were detected 
on the range within 72 hours after training ended (Joyce et al., 2019). 
However, Blainville's beaked whales have been documented to remain on-
range to forage throughout the year (Henderson et al., 2016), 
indicating the AUTEC range may be a preferred foraging habitat 
regardless of the effects of active sonar noise, or it could be that 
there are no long-term consequences of the sonar activity. In the SOCAL 
Range Complex, researchers conducting photo-identification studies have 
identified approximately 100 individual goose-beaked whales, with 40 
percent having been seen in one or more prior years, with re-sightings 
up to 7 years apart, indicating a possible on-range resident population 
(Falcone & Schorr, 2014; Falcone et al., 2009).
    The probability of Blainville's beaked whale group vocal periods on 
the Pacific Missile Range Facility were modeled during periods of (1) 
no naval activity, (2) naval activity without hull-mounted MFA sonar, 
and (3) naval activity with hull-mounted MFA sonar (Jacobson et al., 
2022). At a received level of 150 dB re 1 [mu]Pa RMS, the probability 
of detecting a group vocal period during MFA sonar use decreased by 77 
percent compared to periods when general training activity was ongoing, 
and by 87 percent compared to baseline (no naval activity) conditions. 
Jacobsen et al (2022) found a greater reduction in probability of a 
group vocal period with MFA sonar than observed in a prior study of the 
same species at the AUTEC range (Moretti et al., 2014), which may be 
due to the baseline period in the AUTEC study including naval activity 
without MFA sonar, potentially lowering the baseline group vocal period 
activity in that study, or due to differences in the residency of the 
populations at each range.
    Stanistreet et al. (2022) used passive acoustic recordings during a 
multinational navy activity to assess marine mammal acoustic presence 
and behavioral response to especially long bouts of sonar lasting up to 
13 consecutive hours, occurring repeatedly over 8 days (median and 
maximum SPL = 120 dB and 164 dB). Goose-beaked whales and sperm whales 
substantially reduced how often they produced clicks during sonar, 
indicating a decrease or cessation in foraging behavior. Few previous 
studies have shown sustained changes in foraging or displacement of 
sperm whales, but there was an absence of sperm whale clicks for 6 
consecutive days of sonar activity. Sperm whales returned to baseline 
levels of clicks within days after the activity, but beaked whale 
detection rates remained low even 7 days after the exercise. In 
addition, there were no detections from a Mesoplodon beaked whale 
species within the area during, and at least 7 days after, the sonar 
activity. Clicks from northern bottlenose whales and Sowerby's beaked 
whales were also detected but were not frequent enough at the recording 
site used to compare clicks between baseline and sonar conditions.
    Goose-beaked whale behavioral responses (i.e., deep and shallow 
dive durations, surface interval durations, inter-deep dive intervals) 
on the Southern California Anti-Submarine Warfare Range were modeled 
against predictor values that included helicopter dipping sonar, mid-
power MFA sonar and hull-mounted, high-power MFA sonar along with other 
non-MFA sonar predictors (Falcone et al., 2017). They found both 
shallow and deep dive durations increased as the proximity to both mid- 
and high-powered sources decreased, and found that surface intervals 
and inter-deep dive intervals increased in the presence of both types 
of sonars (helicopter dipping and hull-mounted), although surface 
intervals shortened during

[[Page 19921]]

periods without MFA sonar. Proximity of source and receiver were 
important considerations, as the responses to the mid-power MFA sonar 
at closer ranges were comparable to the responses to the higher source 
level vessel sonar, as was the context of the exposure. Helicopter 
dipping sonars are shorter duration and randomly located, therefore 
more difficult to predict or track by beaked whales and potentially 
more likely to elicit a response, especially at closer distances (3.7 
to 15.5 mi (6 to 25 km))(Falcone et al., 2017). Sea floor depths and 
quantity of light (i.e., lunar cycle) are also important variables to 
consider in BRSs, as goose-beaked whale foraging dive depth increased 
with sea floor depth (maximum 6,561.7 ft (2,000 m)) and the amount of 
time spent at foraging depths (and likely foraging) was greater at 
night (likely avoiding predation by staying deeper during periods of 
bright lunar illumination), although they spent more time near the 
surface during the night, as well, particularly on dark nights with 
little moonlight, (Barlow et al., 2020). Sonar occurred during 10 
percent of the dives studied and had little effect on the resulting 
dive metrics. Watwood et al. (2017) found that the longer the duration 
of a sonar event, the greater reduction in detected goose-beaked whale 
group dives and, as helicopter dipping events occurred more frequently 
but with shorter durations than periods of hull-mounted sonar, when 
looking at the number of detected group dives there was a greater 
reduction during periods of hull-mounted sonar than during helicopter 
dipping sonar. DiMarzio et al. (2019) also found that group vocal 
periods (i.e., clusters of foraging pulses), on average, decreased 
during sonar events on the Southern California Anti-Submarine Warfare 
Range, though the decline from before the event to during the event was 
significantly less for helicopter dipping events than hull-mounted 
events, and there was no difference in the magnitude of the decline 
between vessel-only events and events with both vessels and 
helicopters. Manzano-Roth et al. (2022) analyzed long-term passive 
acoustic monitoring data from the Pacific Missile Range Facility in 
Kaua'i, Hawaii, and found beaked whales reduced group vocal periods 
during submarine command course events and remained low for a minimum 
of 3 days after the MFA sonar activity.
    Harbor porpoise behavioral responses have been researched 
extensively using acoustic deterrent and acoustic harassment devices; 
however, BRSs using sonar are limited. Kastelein et al. (2018b) found 
harbor porpoises did not respond to low-duty cycle mid-frequency sonar 
tones (3.5-4.1 kHz at 2.7 percent duty cycle; e.g., one tone per 
minute) at any received level, but one individual did respond (i.e., 
increased jumping, increased respiration rates) to high-duty cycle 
sonar tones (3.5-4.1 kHz at 96 percent duty cycle; e.g., continuous 
tone for almost a minute).
    Behavioral responses by odontocetes (other than beaked whales and 
harbor porpoises) to sonar and other transducers include horizontal 
avoidance, reduced breathing rates, changes in behavioral state, 
changes in dive behavior (Antunes et al., 2014; Isojunno et al., 2018; 
Isojunno et al., 2017; Isojunno et al., 2020; Miller, 2012; Miller et 
al., 2011; Miller et al., 2014), and, in one study, separation of a 
killer whale calf from its group (Miller et al., 2011). Some species of 
dolphin (e.g., bottlenose, spotted, spinner, Clymene, Pacific white-
sided, rough-toothed) are frequently documented bowriding with vessels 
and the drive to engage in bowriding, whether for pleasure or energetic 
savings (Fiori et al., 2024) may supersede the impact of associated 
sonar noise (W[uuml]rsig et al., 1998).
    In controlled exposure experiments on captive odontocetes, Houser 
et al., (2013a) recorded behavioral responses from bottlenose dolphins 
with 3 kHz sonar-like tones between 115-185 dB re 1 [mu]Pa, and 
individuals across 10 trials demonstrated a 50 percent probability of 
response at 172 dB re 1 [mu]Pa. Multiple studies have been conducted on 
bottlenose dolphins and beluga whales to measure TTS (Finneran et al., 
2003a; Finneran et al., 2001; Finneran et al., 2005; Finneran & 
Schlundt, 2004; Schlundt et al., 2000). During these studies, when 
individuals were presented with 1-second tones up to 203 dB re 1 
[mu]Pa, responses included changes in respiration rate, fluke slaps, 
and a refusal to participate or return to the location of the sound 
stimulus, including what appeared to be deliberate attempts by animals 
to avoid a sound exposure or to avoid the location of the exposure site 
during subsequent tests (Finneran et al., 2002; Schlundt et al., 2000). 
Bottlenose dolphins exposed to more intense 1-second tones exhibited 
short-term changes in behavior above received levels of 178-193 dB re 1 
[mu]Pa, and beluga whales did so at received levels of 180-196 dB re 1 
[mu]Pa and above.
    While several opportunistic observations of odontocete (other than 
beaked whales and harbor porpoises) responses have been recorded during 
previous Navy activities and BRSs that employed sonar and sonar-like 
sources, it is difficult to definitively attribute responses of non-
focal species to sonar exposure. Responses range from no response to 
potential highlight-impactful responses, such as the separation of a 
killer whale calf from its group (Miller et al., 2011). This may be 
due, in part, to the variety of species and sensitivities of the 
odontocete taxonomic group, as well as the breadth of study types 
conducted and field observations, leading to the assessment of both 
contextually driven and dose-based responses. The available data 
indicate exposures to sonar in close proximity and with multiple 
vessels approaching an animal likely lead to higher-level responses by 
most odontocete species, regardless of received level or behavioral 
state. However, when sources are further away and moving in variable 
directions, behavioral responses are likely driven by behavioral state, 
individual experience, or species-level sensitivities, as well as 
exposure duration and received level, with the likelihood of response 
increasing with increased received levels. As such, it is expected 
odontocete behavioral responses to sonar and other transducers will 
vary by species, populations, and individuals, and long-term 
consequences or population-level effects are likely dependent upon the 
frequency and duration of the exposure and resulting behavioral 
response.
    Pinniped behavioral response to sonar and other transducers is 
context-dependent (e.g., Hastie et al., 2014; Southall et al., 2019). 
All studies on pinniped response to sonar thus far have been limited to 
captive animals, though, based on exposures of wild pinnipeds to vessel 
noise and impulsive sounds (see Responses Due to Vessel Noise section 
and Responses Due to Impulsive Noise section below), pinnipeds may only 
respond strongly to military sonar that is in close proximity or 
approaching an animal. Kvadsheim et al. (2010b) found that captive 
hooded seals exhibited avoidance response to sonar signals between 1-7 
kHz (160 to 170 dB re 1 [micro]Pa rms) by reducing diving activity, 
rapid surface swimming away from the source, and eventually moving to 
areas of least SPL. However, the authors noted a rapid adaptation in 
behavior (passive surface floating) during the second and subsequent 
exposures, indicating a level of habituation within a short amount of 
time. Kastelein et al. (2015c) exposed captive harbor seals to three 
different sonar signals at 25 kHz with variable waveform 
characteristics and duty cycles and found individuals responded

[[Page 19922]]

to a frequency modulated signal at received levels over 137 dB re 1 
[micro]Pa by hauling out more, swimming faster, and raising their heads 
or jumping out of the water. However, seals did not respond to a 
continuous wave or combination signals at any received level (up to 156 
dB re 1 [micro]Pa). Houser et al. (2013a) conducted a study to 
determine behavioral responses of captive California sea lions to MFA 
sonar at various received levels (125 to 185 dB re 1 [micro]Pa). They 
found younger animals (less than 2 years old) were more likely to 
respond than older animals and responses included increased respiration 
rate, increased time spent submerged, refusal to participate in a 
repetitive task, and hauling out. Most responses below 155 dB re 1 
[micro]Pa were changes in respiration, while more severe responses 
(i.e., refusing to participate, hauling out) began to occur over 170 dB 
re 1 [micro]Pa, and many of the most severe responses came from the 
young sea lions.
Responses Due to Impulsive Noise--
    Impulsive signals have a rapid rise time and higher instantaneous 
peak pressure than other signal types, particularly at close range, 
which means they are more likely to cause startle or avoidance 
responses. At long distances, however, the rise time increases as the 
signal duration lengthens (similar to a ``ringing'' sound), making the 
impulsive signal more similar to a non-impulsive signal (Hastie et al., 
2019; Martin et al., 2020). Behavioral responses from explosive sounds 
are likely to be similar to responses studied for other impulsive 
noise, such as those produced by air guns and impact pile driving. Data 
on behavioral responses to impulsive sound sources are limited across 
all marine mammal groups, with only a few studies available for 
mysticetes and odontocetes.
    Mysticetes have varied responses to impulsive sound sources, 
including avoidance, aggressive directed movement towards the source, 
reduced surface intervals, altered swimming behavior, and changes in 
vocalization rates (Gordon et al., 2003; McCauley et al., 2000a; 
Richardson et al., 1985; Southall et al., 2007). Studies have been 
conducted on many baleen whale species, including gray, humpback, blue, 
fin and bowhead whales; it is assumed that these responses are 
representative of all baleen whale species. The behavioral state of the 
whale seems to be an integral part of whether the animal responds and 
how they respond, as does the location and movement of the sound 
source, more than the received level of the sound.
    If an individual is engaged in migratory behavior, it may be more 
likely to respond to impulsive noise, and some species may be more 
sensitive than others. Migrating gray whales showed avoidance responses 
to seismic vessels at received levels between 164 and 190 dB re 1 
[mu]Pa (Malme et al., 1986, Malme et al., 1988). In one study, McCauley 
et al. (1998) found that migrating humpback whales in Australia showed 
avoidance behavior at ranges of 3.1-5 mi (5-8 km) from a seismic array 
during observational studies and controlled exposure experiments, and 
another study found humpback whales in Australia decreased their dive 
times and reduced their swimming speeds (Dunlop et al., 2015). However, 
when comparing received levels and behavioral responses between air gun 
ramp-up versus constant noise level of air guns, humpback whales did 
not change their dive behavior but did deviate from their predicted 
heading and decreased their swim speeds, deviating more during the 
constant noise source trials but reducing swim speeds more during ramp-
up trials (Dunlop et al., 2016). In both cases, there was no dose-
response relationship with the received level of the air gun noise, and 
similar responses were observed in control trials without air guns 
(vessel movement remained constant across trials), so some responses 
may have been due to vessel presence and not received level from the 
air guns. Social interactions between males and mother-calf pairs were 
reduced in the presence of vessels towing seismic air gun arrays, 
regardless of whether the air guns were active or not; which indicates 
that it was likely the presence of vessels (rather than the impulsive 
noise generated from active air guns) that affected humpback whale 
behavior (Dunlop et al., 2020).
    Proximity of the impulsive source is another important factor to 
consider when assessing the potential for behavioral responses in 
marine mammals. Dunlop et al. (2017) found that groups of humpback 
whales were more likely to avoid a smaller air gun array at closer 
proximity than a larger air gun array, despite the same received level, 
showing the difference in response between arrays has more to do with 
the combined effects of received level and source proximity. In this 
study, responses were varied and generally small, with short-term 
course deviations of about 1,640 ft (500 m). Studies on bowhead whales 
have shown they may be more sensitive than other species to impulsive 
noise, as individuals have shown clear changes in diving and breathing 
patterns up to 45.4 mi (73 km) from seismic vessels with received 
levels as low as 125 dB re 1 [mu]Pa (Malme et al. 1988). Richardson et 
al. (1995b) documented bowhead whales exhibiting avoidance behaviors at 
a distance of more than 12.4 mi (20 km) from seismic vessels when 
received levels were as low as 120 dB re 1 [mu]Pa, although most did 
not show active avoidance until 5 mi (8 km) from the source. Although 
bowhead whales may avoid the area around seismic surveys, from 3.7 to 5 
mi (6 to 8 km) (Koski and Johnson 1987, as cited in Gordon et al., 
2003) out to 12.4 or 18.6 mi (20 or 30 km) (Richardson et al., 1999), a 
study by Robertson et al. (2013) supports the idea that behavioral 
responses are contextually dependent, and that during seismic 
operations, bowhead whales may be less ``available'' for counting due 
to alterations in dive behavior but that they may not have completely 
vacated the area.
    In contrast, noise from seismic surveys was not found to impact 
feeding behavior or exhalation rates in western gray whales while 
resting or diving off the coast of Russia (Gailey et al., 2007; 
Yazvenko et al., 2007); however, the increase in vessel traffic 
associated with surveys and the proximity of the vessels to the whales 
did affect the orientation of the whales relative to the vessels and 
shortened their dive-surface intervals (Gailey et al., 2016). They also 
increased their speed and distance from the noise source and have been 
documented in one case study swimming towards shore to avoid an 
approaching seismic vessel (Gailey et al., 2022). Todd et al. (1996) 
found no clear short-term behavioral responses by foraging humpbacks to 
explosions associated with construction operations in Newfoundland but 
did see a trend of increased rates of net entanglement closer to the 
noise source, possibly indicating a reduction in net detection 
associated with the noise through masking or TTS. Distributions of fin 
and minke whales were modeled with multiple environmental variables and 
with the occurrence or absence of seismic surveys, and no evidence of a 
decrease in sighting rates relative to seismic activity was found for 
either species (Vilela et al., 2016). Their distributions were driven 
entirely by environmental variables, particularly those linked to prey, 
including warmer sea surface temperatures, higher chlorophyll-a values, 
and higher photosynthetically available radiation (a measure of primary 
productivity). Sighting rates based on over 8,000 hours of baleen and 
toothed whale survey data were compared on regular vessel

[[Page 19923]]

surveys versus both active and passive periods of seismic surveys 
(Kavanagh et al., 2019). Models of sighting numbers were developed, and 
it was determined that baleen whale sightings were reduced by 88 
percent during active and 87 percent during inactive phases of seismic 
surveys compared to regular surveys. These results seemed to occur 
regardless of geographic location of the survey; however, when only 
comparing active versus inactive periods of seismic surveys the 
geographic location did seem to affect the change in sighting rates.
    Mysticetes seem to be the most behaviorally sensitive taxonomic 
group of marine mammals to impulsive sound sources, with possible 
avoidance responses occurring out to 18.6 mi (30 km) and vocal changes 
occurring in response to sounds over 62.1 mi (100 km) away. However, 
they are also the most studied taxonomic group, yielding a larger 
sample size and greater chance of finding behavioral responses to 
impulsive noise. Also, their responses appear to be behavior-dependent, 
with most avoidance responses occurring during migration behavior and 
little observed response during feeding behavior. These response 
patterns are likely to hold true for impulsive sources used by the 
Action Proponents; however, their impulsive sources would largely be 
stationary (e.g., explosives fired at a fixed target, small air guns), 
and short term (hours rather than days or weeks) versus those in the 
aforementioned studies, so responses would likely occur in closer 
proximity to animals or not at all.
    Odontocete responses to impulsive noise are not well studied and 
the majority of data have come from seismic (i.e., air gun) surveys, 
pile driving, and construction activities, while only a few studies 
have been done to understand how explosive sounds impact odontocetes. 
What data are available show they may be less sensitive than mysticetes 
to impulsive sound and that responses occur at closer distances. This 
may be due to the predominance of low-frequency sound associated with 
impulsive sources that propagates across long distances and overlaps 
with the range of best hearing for mysticetes but is below that range 
for odontocetes. Even harbor porpoises--shown to be highly sensitive to 
most sound sources, avoiding both stationary (e.g., pile driving) and 
moving (e.g., seismic survey vessels) impulsive sound sources out to 
approximately 12.4 mi (20 km) (e.g., Haelters et al., 2014; Pirotta et 
al., 2014)--have short-term responses, returning to an area within 
hours upon cessation of the impulsive noise.
    Although odontocetes are generally considered less sensitive, 
impulsive noise does impact toothed whales in a variety of ways. In one 
study, dolphin detections were compared during 30 second periods 
before, during, and after underwater detonations near naval mine 
neutralization exercises in VACAPES. Lammers et al. (2017) found that 
within 30 seconds after an explosion, the immediate response was an 
increase in whistles compared to the 30 seconds before an explosion, 
and that there was a reduction in dolphin acoustic activity during the 
day of and day after the exercise within 3.7 mi (6 km). This held true 
only during daytime, as nighttime activity did not appear different 
than before the exercise, and two days after the explosion there seemed 
to be an increase in daytime acoustic activity, indicating dolphins may 
have returned to the area or resumed vocalizations (Lammers et al., 
2017). Weaver (2015) documented potential sex-based differences in 
behavioral responses to impulsive noise during construction (including 
blasting) of a bridge over a waterway commonly used by bottlenose 
dolphins, where females decreased area use and males continued using 
the area, perhaps indicating differential habitat uses.
    When exposed to multiple impulses from a seismic air gun, Finneran 
et al. (2015) noted some captive dolphins turned their heads away from 
the source just before the impulse, indicating they could anticipate 
the timing of the impulses and may be able to behaviorally mediate the 
exposure to reduce their received level. Kavanagh et al. (2019) found 
sightings of odontocete whales decreased by 53 percent during active 
phases of seismic air gun surveys and 29 percent during inactive phases 
compared to control surveys. Heide-Jorgensen et al. (2021) found that 
narwhals exposed to air gun noise in an Arctic fjord were sensitive to 
seismic vessels over 6.8 mi (11 km) away, even though the small air gun 
source reached ambient noise levels around 1.9 mi (3 km) (source level 
of 231 dB re 1 [mu]Pa at 1 m) and large air gun source reached ambient 
noise levels around 6.2 mi (10 km) (source level 241 dB re 1 [mu]Pa at 
1 m). Behavioral responses included changes in swimming speed and 
swimming direction away from the impulsive sound source and towards the 
shoreline. Changes in narwhal swimming speed was context-dependent and 
usually increased in the presence of vessels but decreased (a 
``freeze'' response) in response to closely approaching air gun pulses 
(Heide-Jorgensen et al., 2021). A cessation of feeding was also 
documented, when the impulsive noise was less than 6.2 mi (10 km) away, 
although received SELs were less than 130 dB re 1 [mu]Pa\2\s for either 
air gun at this distance. However, because of this study's research 
methods and criteria, the long-distance responses of narwhals may be 
conservatively estimating narwhals' range to behavioral response.
    Similarly, harbor porpoises seem to have an avoidance response to 
seismic surveys by leaving the area and decreasing foraging activity 
within 3.1-6.2 mi (5-10 km) of the survey, as evidenced by both a 
decrease in vocalizations near the survey and an increase in 
vocalizations at a distance (Pirotta et al., 2014; Thompson et al., 
2013a). The response was short-term, as the porpoises returned to the 
area within 1 day upon cessation of the air gun operation. 
Sarnoci[nacute]ska et al. (2020) placed autonomous recording devices 
near oil and gas platforms and control sites to measure harbor porpoise 
acoustic activity during seismic air gun surveys. They noted a dose-
response effect, with the lowest amount of porpoise activity closest to 
the seismic vessel (SELsingle shot = 155 dB re 1 [mu]Pa\2\s) 
and increasing porpoise activity out to 5 to 7.5 mi (8 to 12 km), and 
that distance to the seismic vessel, rather than sound level, was a 
better model predictor of porpoise activity. Overall porpoise activity 
in the seismic survey area was similar to the control sites 
(approximately 9.3 mi (15 km) apart), which may indicate the harbor 
porpoises were moving around the area to avoid the seismic vessel 
without leaving the area entirely.
    Pile driving, another activity that produces impulsive sound, 
elicited a similar response in harbor porpoises. Benhemma-Le Gall et 
al., 2021 examined changes in porpoise presence and foraging at two 
offshore windfarms between control (102-104 dB) and construction 
periods (155-161 dB), and found decreased presence (8-17 percent) and 
decreased foraging activity (41-62 percent) during construction 
periods. Porpoises were displaced up to 7.5 mi (12 km) away from pile 
driving and 2.5 mi (4 km) from construction vessels. Multiple studies 
have documented strong avoidance responses by harbor porpoises out to 
12.4 mi (20 km) during pile driving activity, however, animals returned 
to the area after the activity stopped (Brandt et al., 2011; D[auml]hne 
et al., 2014; Haelters et al., 2014; Thompson et al., 2010; Tougaard et 
al., 2005; Tougaard et al., 2009). When bubble curtains were deployed 
around pile driving, the avoidance distance appeared to be reduced by 
half

[[Page 19924]]

to 7.5 mi (12 km), and the animals returned to the area after 
approximately 5 hours rather than 1 day later (D[auml]hne et al., 
2017). Further, Bergstr[ouml]m et al. (2014) found that although there 
was a high likelihood of acoustic disturbance during wind farm 
construction (including pile driving), the impact was short-term, and 
Graham et al. (2019) found that the distance at which behavioral 
responses of harbor porpoises were likely decreased over the course of 
a construction project, suggesting habituation to impulsive pile-
driving noise. Kastelein et al. (2013b) exposed captive harbor 
porpoises to impact pile driving noise, and found that respiration 
rates increased above 136 dB re 1 [micro]Pa (zero-to-peak), and at 
higher sound levels individuals jumped more frequently. When a single 
harbor porpoise was exposed to playbacks of impact pile driving noise 
with different bandwidths, Kastelein et al. (2022) found the animal's 
behavioral response (i.e., swim speed, respiration rate, jumping) 
decreased with bandwidth.
    Overall, odontocete behavioral responses to impulsive sound sources 
are likely species- and context-dependent. Responses might be expected 
close to a noise source, under specific behavioral conditions such as 
females with offspring, or for sensitive species such as harbor 
porpoises, while many other species demonstrate little to no behavioral 
response.
    Pinnipeds seem to be the least sensitive marine mammal group to 
impulsive noise (Richardson et al., 1995b; Southall et al., 2007), and 
some may even experience hearing effects before exhibiting a behavioral 
response (Southall et al., 2007). Some species may be more sensitive 
and are only likely to respond (e.g., startling, entering the water, 
ceasing foraging) to loud impulsive noises in close proximity, but only 
for brief periods of time before returning to their previous behavior. 
Demarchi et al. (2012) exposed Steller sea lions to in-air explosive 
blasts, which resulted in increased activity levels and often caused 
re-entry into the water from a hauled out state. These responses were 
brief (lasting only minutes) and the animals returned to haul outs and 
there were no documented lasting behavioral impacts in the days 
following the explosions.
    Ringed seals exhibited little or no response to pile driving noise 
with mean underwater levels of 157 dB re 1 [mu]Pa and in-air levels of 
112 dB re 20 [mu]Pa (Blackwell et al., 2004) while harbor seals vacated 
the area surrounding an active pile driving site at estimated received 
levels between 166-178 dB re 1 [mu]Pa SPL (peak to peak), returning 
within 2 hours of the completion of piling activities (Russell et al., 
2016). Wild-captured gray seals exposed to a startling treatment (sound 
with a rapid rise time and a 93 dB sensation level (the level above the 
animal's hearing threshold at that frequency) avoided a known food 
source, whereas animals exposed to a non-startling treatment (sound 
with a slower rise time but peaking at the same level) did not react or 
habituated during the exposure period (G[ouml]tz and Janik, 2011). 
These results underscore the importance of the characteristics of an 
acoustic signal in predicting an animal's response of habituation.
    Hastie et al. (2021) studied how the number and severity of 
avoidance events may be an outcome of marine mammal cognition and risk 
assessment using captive grey seals. Five individuals were given the 
option to forage in a high- or low-density prey patch while 
continuously exposed to silence or anthropogenic noise (pile driving or 
tidal turbine operation) playbacks (148 dB re 1 [mu]Pa at 1 m). For 
each trial, one prey patch was closer to the source, therefore having a 
higher received level in experimental exposures than the other prey 
patch. The authors found that foraging success was highest during 
silent periods and that the seals avoided both anthropogenic noises 
with higher received levels when the prey density was limited (low-
density prey patch). The authors concluded the seals made foraging 
decisions within the trials based on both the energetic value of the 
prey patch (low-density corresponding to low energetic value, high-
density corresponding to high energetic value), and the nature and 
location of the acoustic signal relative to the prey patches of 
different value.
Responses Due to Vessel Noise--
    Mysticetes have varied responses to vessel noise and presence, from 
having no response to approaching vessels to exhibiting an avoidance 
response by both horizontal (swimming away) and vertical (increased 
diving) movement (Baker et al., 1983; Fiori et al., 2019; Gende et al., 
2011; Watkins, 1981). Avoidance responses include changing swim 
patterns, speed, or direction (Jahoda et al., 2003), remaining 
submerged for longer periods of time (Au & Green, 2000), and performing 
shallower dives with more frequent surfacing. Behavioral responses to 
vessels range from smaller-scale changes, such as altered breathing 
patterns (e.g., Baker et al., 1983; Jahoda et al., 2003), to larger-
scale changes such as a decrease in apparent presence (Anderwald et 
al., 2013). Other common behavioral responses include changes in 
vocalizations, surface time, feeding and social behaviors (Au & Green, 
2000; Dunlop, 2019; Fournet et al., 2018; Machernis et al., 2018; 
Richter et al., 2003; Williams et al., 2002a). For example, NARWs have 
been reported to increase the amplitude or frequency of their 
vocalizations or call at a lower rate in the presence of increased 
vessel noise (Parks et al., 2007; Parks et al., 2011), but generally 
demonstrate little to no response to vessels or sounds from approaching 
vessels and often continue to use habitats in high vessel traffic areas 
(Nowacek et al. 2004a). This lack of response may be due to habituation 
to the presence and associated noise of vessels in NARW habitat or may 
be due to propagation effects that may attenuate vessel noise near the 
surface (Nowacek et al., 2004a; Terhune & Verboom, 1999).
    Similarly, sei whales have been observed ignoring the presence of 
vessels entirely and even pass close to vessels (Reeves et al., 1998). 
Historically, fin whales tend to ignore vessels at a distance (Watkins, 
1981) or habituate to vessels over time (Watkins, 1986) but still 
demonstrate vocal modifications (e.g., decreased frequency parameters 
of calls) during vessel traffic. Ramesh et al. (2021) found that fin 
whale calls in Ireland were less likely to be detected for every 1 dB 
re 1 [mu]Pa/minute increase in shipping noise levels. In the presence 
of tour boats in Chile, fin whales were changing their direction of 
movement more frequently, with less linear movement than occurred 
before the boats arrived; this behavior may represent evasion or 
avoidance of the boats (Santos-Carvallo et al., 2021). The increase in 
travel swim speeds after the vessels departed may be related to the 
rapid speeds at which the vessels traveled, sometimes in front of fin 
whales, leading to additional avoidance behavior post-exposure.
    Mysticete behavioral responses to vessels may also be affected by 
vessel behavior (Di Clemente et al., 2018; Fiori et al., 2019). 
Avoidance responses occurred most often after ``J'' type vessel 
approaches (i.e., traveling parallel to the whales' direction of 
travel, then overtaking the whales by turning in front of the group) 
compared to parallel or direct approaches. Mother humpbacks were 
particularly sensitive to direct and J type approaches and spent 
significantly more time diving in response (Fiori et al., 2019). The 
presence of a passing vessel did not change the behavior of resting 
humpback whale mother-calf pairs, but

[[Page 19925]]

fast vessels with louder low-frequency weighted source levels (173 dB 
re 1 [mu]Pa, equating to weighted received levels of 133 dB re 1 
[mu]Pa) at an average distance of 328 ft (100 m) resulted in a 
decreased resting behavior and increases in dives, swim speeds, and 
respiration rates (Sprogis et al., 2020). Humpback whale responses to 
vessel disturbance were dependent on their behavioral state. Di 
Clemente et al. (2018) found that when vessels passed within 1,640 ft 
(500 m) of humpback whales, individuals would continue to feed if 
already engaged in feeding behavior but were more likely to start 
swimming if they were surface active when approached. In response to an 
approaching large commercial vessel in an area of high ambient noise 
levels (125-130 dB re 1 [mu]Pa), a tagged female blue whale turned 
around mid-ascent and descended perpendicular to the vessel's path 
(Szesciorka et al., 2019). The whale did not respond until the vessel's 
closest point of approach (328 ft (100 m) distance, 135 dB re 1 
[mu]Pa), which was 10 dB above the ambient noise levels. After the 
vessel passed, the whale ascended to the surface again with a three-
minute delay.
    Overall, mysticete responses to vessel noise and traffic are 
varied, and habituation or changes to vocalization are predominant 
long-term responses. When baleen whales do avoid vessels, they seem to 
do so by altering their swim and dive patterns to move away from the 
vessel. Although a lack of response in the presence of a vessel may 
minimize potential disturbance from passing vessels, it does increase 
the whales' vulnerability to vessel strike, which may be of greater 
concern for mysticetes than vessel noise.
    Odontocete responses due to vessel noise are varied and context-
dependent, and it is difficult to separate the impacts of vessel noise 
from the impacts of vessel presence. Vessel presence has been shown to 
interrupt feeding behavior in delphinids in some studies (Meissner et 
al., 2015; Pirotta et al., 2015b) while a recent study by Mills et al. 
(2023) found that, in an important foraging area, bottlenose dolphins 
may continue to forage and socialize even while constantly exposed to 
high vessel traffic. Ng and Leung (2003) found that the type of vessel, 
approach, and speed of approach can all affect the probability of a 
negative behavioral response and, similarly, Guerra et al. (2014) 
documented varied responses in group structure and vocal behavior.
    While most odontocetes have documented neutral responses to 
vessels, avoidance (Bejder et al., 2006a; W[uuml]rsig et al., 1998) and 
attraction (Norris & Prescott, 1961; Ritter, 2002; Shane et al., 1986; 
Westdal et al., 2023; W[uuml]rsig et al., 1998) behaviors have also 
been observed (Hewitt, 1985). Archer et al. (2010) compared the 
responses of dolphin populations far offshore that were often targeted 
by tuna fisheries to populations closer (less than 100 nmi (185.2 km)) 
to shore and found the fisheries-associated populations (spotted, 
spinner, and common dolphins) showed evasive behavior when approached 
by vessels while those nearshore species not associated with offshore 
fisheries (coastal spotted and bottlenose dolphins) tended to be 
attracted to vessels.
    Arranz et al. (2021) used different engine types to determine 
whether behavioral responses of short-finned pilot whales were 
attributable to vessel noise, vessel presence, or both. Mother-calf 
pairs were approached by the same vessel outfitted with either 
``quiet'' electric engines or ``noisy'' traditional combustion engines, 
controlling for approach speed and distance. Arranz et al. (2021) found 
mother pilot whales rested less and calves nursed less in response to 
both types of engines compared to control conditions, but only the 
``noisy'' engine caused significant impacts (29 percent and 81 percent, 
respectively).
    Smaller vessels tend to generate more noise in higher frequency 
bands, are more likely to approach odontocetes directly, and spend more 
time near an animal. Carrera et al. (2008) found tour boat activity can 
cause short-term displacement of dolphins, and Haviland-Howell et al. 
(2007) documented longer term or repetitive displacement of dolphins 
due to chronic vessel noise. Delphinid behavioral states also change in 
the presence of small tour vessels that often approach animals: travel 
and resting increases, foraging and social behavior decreases, and 
animals move closer together (Cecchetti et al., 2017; Clarkson et al., 
2020; Kassamali-Fox et al., 2020; Meissner et al., 2015). Most studies 
on behavioral responses of bottlenose dolphin to vessel traffic show at 
least short-term changes in behavior, activities, or vocalization 
patterns when vessels are nearby (Acevedo, 1991; Arcangeli & Crosti, 
2009; Berrow & Holmes, 1999; Fumagalli et al., 2018; Gregory & Rowden, 
2001; Janik & Thompson, 1996; Lusseau, 2004; Marega et al., 2018; 
Mattson et al., 2005; Perez-Ortega et al., 2021; Puszka et al., 2021; 
Scarpaci et al., 2000).
    Information is limited on beaked whale responses to vessel noise, 
but W[uuml]rsig et al. (1998) noted that most beaked whales seem to 
exhibit avoidance behaviors when exposed to vessels and beaked whales 
may respond to all anthropogenic noise (i.e., sonar, vessel) at similar 
sound levels (Aguilar de Soto et al., 2006; Tyack et al., 2011; Tyack, 
2009). The information available includes a disruption of foraging by a 
vocalizing goose-beaked whale in the presence of a passing vessel 
(Aguilar de Soto et al., 2006) and restriction of group movement, or 
possibly reduction in the number of individuals clicking within the 
group, after exposure to broadband (received level of 135 dB re 1 
[mu]Pa) vessel noise up to at least 3.2 mi (5.2 km) away from the 
source, though no change in duration of Blainville's beaked whale 
foraging dives was observed (Pirotta et al., 2012).
    Porpoises and small delphinids are known to be sensitive to vessel 
noise, as well. Frankish et al. (2023) found harbor porpoises more 
likely to avoid large commercial vessels via horizontal movement during 
the day and vertical movement at night, which supports previous 
research that the species routinely avoids large motorized vessels 
(Polacheck and Thorpe, 1990). Harbor porpoises have also been 
documented responding to vessels with increased changes in behavioral 
state and significantly decreased feeding (Akkaya Bas et al., 2017), 
fewer clicks (Sairanen, 2014), and fewer prey capture attempts and have 
disrupted foraging when vessels pass closely and noise levels are 
higher (Wisniewska et al., 2018). Habituation to vessel noise and 
presence was observed for a resident population of harbor porpoises 
that was in regular proximity to vessel traffic (32.8 ft to 0.6 mi (10 
m to 1 km) away); the population had no response in 74 percent of 
interactions and an avoidance response in 26 percent of interactions. 
It should be noted that fewer responses in populations of odontocetes 
regularly subjected to high levels of vessel traffic could be a sign of 
habituation, or it could be that the more sensitive individuals in the 
population have abandoned that area of higher human activity. Most 
avoidance responses were the result of fast-moving or steady plane-
hulling motorized vessels and the vessel type and speed were considered 
to be more relevant than vessel presence, as few responses were 
observed to non-motorized or stationary vessels (Oakley et al., 2017). 
Similarly, Akkaya Bas et al. (2017) found that when fast moving vessels 
were within 164 ft (50 m) of harbor porpoises, there was an 80 percent 
probability of change in swimming direction but only a 40 percent 
probability of change when vessels were beyond 1,312.3 ft (400 m). 
Frankish et al. (2023) found that harbor

[[Page 19926]]

porpoises were most likely to avoid vessels less than 984.3 ft (300 m) 
away but, 5-10 percent of the time, they would also respond to vessels 
more than 1.2 mi (2 km) away, signifying that were not just attuning to 
vessel presence but vessel noise, as well. Although most vessel noise 
is constrained to frequencies below 1 kHz, at close ranges vessel noise 
can extend into mid- and high frequencies (into the tens of kHz) 
(Hermannsen et al., 2014; Li et al., 2015) and it is these frequencies 
that harbor porpoises are likely responding to; the mean M-weighted 
received SPL threshold for a response at these frequencies is 123 dB re 
1 [mu]Pa (Dyndo et al., 2015). M-weighting functions are generalized 
frequency weightings for various groups of marine mammals that were 
defined by Southall et al. (2007) based on known or estimated auditory 
sensitivity at different frequencies, and are used to characterize 
auditory effects of strong sounds. Hermannsen et al. (2019) estimated 
that noise in the 16 kHz frequency band resulting from small 
recreational vessels could cause behavioral directions in harbor 
porpoises, and could be elevated up to 124 dB re 1 [mu]Pa and raise 
ambient noise levels by a maximum of 51 dB. The higher noise levels 
were associated with vessel speed and range, which exceeded the 
threshold levels found by Dyndo et al. (2015) and Wisniewska et al. 
(2018) by 49-85 percent of events with high levels of vessel noise.
    Lusseau and Bejder (2007) have reported some long-term consequences 
of vessel noise on odontocetes but, overall, there is little 
information on the long-term and cumulative impacts of vessel noise 
(National Academies of Sciences Engineering and Medicine, 2017; 
National Marine Fisheries Service, 2007). Many researchers speculate 
that long-term impacts may occur on odontocete populations that 
experience repeated interruption of foraging behaviors (Stockin et al., 
2008), and Southall et al. (2021) indicates that, in many contexts, the 
localized and coastal home ranges typical of many species make them 
less resilient to this chronic stressor than mysticetes.
    Context and experience likely play a role in pinnipeds response to 
vessel noise, which vary from negative responses including increased 
vigilance and alerting to avoidance to reduced time spent doing 
biologically important activities (e.g., resting, feeding, and nursing) 
(Martin et al., 2023a; Martin et al., 2022; Mikkelsen et al., 2019; 
Richardson et al., 1995b) to attraction or lack of observable response 
(Richardson et al., 1995b). More severe responses, like flushing, could 
be more detrimental to individuals during biologically important 
activities and times, such as during pupping season. Blundell and 
Pendleton (2015) found that vessel presence reduces haul out time of 
Alaskan harbor seals during pupping season and larger vessels elicit 
stronger responses. Cates and Acevedo-Guti[eacute]rrez (2017) modeled 
harbor seal responses to passing vessels at haul out sites in less 
trafficked areas and found the model best predicting flushing behavior 
included number of boats, type of boats, and distance of seals to 
boats. The authors noted flushing occurred more in response to non-
motorized vessels (e.g., kayaks), likely because they tended to pass 
closer (82 to 603.7 ft (25 to 184 m)) to haul out sites than motorized 
vessels (180.4 to 1,939 ft (55 to 591 m)) and tended to occur in groups 
rather than as a single vessel. Cape fur seals were also more 
responsive to vessel noise at sites with a large breeding colony than 
at sites with lower abundances of conspecifics (Martin et al., 2023a). 
A field study of harbor and gray seals showed that seal responses to 
vessels included interruption of resting and foraging during times when 
vessel noise was increasing or at its peak (Mikkelsen et al., 2019). 
And, although no behavioral differences were observed in hauled out 
wild cape fur seals exposed to low (60-64 dB re 20 [mu]Pa RMS SPL), 
medium (64-70 dB) and high-level (70-80 dB) vessel noise playbacks, 
mother-pup pairs spent less time nursing (15-31 percent) and more time 
awake (13-26 percent), vigilant (7-31 percent), and mobile (2-4 
percent) during vessel noise conditions compared to control conditions 
(Martin et al., 2022).
Masking
    Sound can disrupt behavior through masking, or interfering with, an 
animal's ability to detect, recognize, interpret, or discriminate 
between acoustic signals of interest (e.g., those used for 
intraspecific communication and social interactions, prey detection, 
predator avoidance, or navigation) (Clark et al., 2009; Richardson et 
al., 1995; Erbe and Farmer, 2000; Tyack, 2000; Erbe et al., 2016; 
Branstetter and Sills, 2022). Masking occurs when the receipt of a 
sound is interfered with by another coincident sound at similar 
frequencies and at similar or higher intensity and may occur whether 
the coincident sound is natural (e.g., snapping shrimp, wind, waves, 
precipitation) or anthropogenic (e.g., shipping, sonar, seismic 
exploration) in origin. As described in detail in appendix D, section 
D.6.4 (Masking), of the 2024 AFTT Draft Supplemental EIS/OEIS, the 
ability of a noise source to mask biologically important sounds depends 
on the characteristics of both the noise source and the signal of 
interest (e.g., signal-to-noise ratio, temporal variability, 
direction), in relation to each other and to an animal's hearing 
abilities (e.g., sensitivity, frequency range, critical ratios, 
frequency discrimination, directional discrimination, age, or TTS 
hearing loss), and existing ambient noise and propagation conditions. 
Masking these acoustic signals can disturb the behavior of individual 
animals, groups of animals, or entire populations. Masking can lead to 
behavioral changes including vocal changes (e.g., Lombard effect, 
increasing amplitude, or changing frequency), cessation of foraging, 
and leaving an area, to both signalers and receivers, in an attempt to 
compensate for noise levels (Erbe et al., 2016).
    Most research on auditory masking is focused on energetic masking, 
or the ability of the receiver (i.e., listener) to detect a signal in 
noise. However, from a fitness perspective, both signal detection and 
signal interpretation are necessary for success. This type of masking 
is called informational masking and occurs when a signal is detected by 
an animal but the meaning of that signal has been lost. Few data exist 
on informational masking in marine mammals but studies have shown that 
some recognition of predator cues might be missed by species that are 
preyed upon by killer whales if killer whale vocalizations are masked 
(Cur[eacute] et al., 2016; Cur[eacute] et al., 2015; Deecke et al., 
2002; Isojunno et al., 2016; Visser et al., 2016). von Benda-Beckman et 
al. (2021) modeled the effect of pulsed and continuous active sonars 
(CAS) on sperm whale echolocation and found that sonar sounds could 
reduce the ability of sperm whales to find prey under certain 
conditions.
    Under certain circumstances, marine mammals experiencing 
significant masking could also be impaired from maximizing their 
performance fitness in survival and reproduction. Therefore, when the 
coincident (masking) sound is man-made, it may be considered harassment 
when disrupting natural behavioral patterns to the point where the 
behavior is abandoned or significantly altered. It is important to 
distinguish TTS and PTS, which persist after the sound exposure, from 
masking, which only occurs during the sound exposure. Because masking 
(without resulting in threshold shift) is not associated with abnormal 
physiological function, it is not considered a physiological effect, 
but rather a potential behavioral effect.

[[Page 19927]]

    Richardson et al. (1995) argued that the maximum radius of 
influence of an industrial noise (including broadband low-frequency 
sound transmission) on a marine mammal is the distance from the source 
to the point at which the noise can barely be heard. This range is 
determined by either the hearing sensitivity (including critical 
ratios, or the lowest signal-to-noise ratio in which animals can detect 
a signal) of the animal (Finneran and Branstetter, 2013; Johnson et 
al., 1989; Southall et al., 2000) or the background noise level 
present. Industrial masking is most likely to affect some species' 
ability to detect communication calls and natural sounds (i.e., surf 
noise, prey noise, etc.) (Richardson et al., 1995).
    The frequency range of the potentially masking sound is important 
in determining any potential behavioral impacts. For example, low-
frequency signals may have less effect on high-frequency echolocation 
sounds produced by odontocetes but are more likely to affect detection 
of mysticete communication calls and other potentially important 
natural sounds such as those produced by surf and some prey species. 
The masking of communication signals by anthropogenic noise may be 
considered as a reduction in the communication space of animals (e.g., 
Clark et al., 2009; Matthews et al., 2016) and may result in energetic 
or other costs as animals change their vocalization behavior (e.g., 
Miller et al., 2000; Foote et al., 2004; Parks et al., 2007; Di Iorio 
and Clark, 2009; Holt et al., 2009). Masking can be reduced in 
situations where the signal and noise come from different directions 
(Richardson et al., 1995), through amplitude modulation of the signal, 
or through other compensatory behaviors (Houser and Moore, 2014). 
Masking can be tested directly in captive species, but in wild 
populations it must be either modeled or inferred from evidence of 
masking compensation. There are few studies addressing real-world 
masking sounds likely to be experienced by marine mammals in the wild 
(e.g., Cholewiak et al., 2018; Branstetter and Sills, 2023; Branstetter 
et al., 2024).
    High-frequency sounds may mask the echolocation calls of toothed 
whales. Human data indicate low-frequency sound can mask high-frequency 
sounds (i.e., upward masking). Studies on captive odontocetes by Au et 
al. (1974, 1985, 1993) indicate that some species may use various 
processes to reduce masking effects (e.g., adjustments in echolocation 
call intensity or frequency as a function of background noise 
conditions). There is also evidence that the directional hearing 
abilities of odontocetes are useful in reducing masking at the high-
frequencies these cetaceans use to echolocate, but not at the low-to-
moderate frequencies they use to communicate (Zaitseva et al., 1980). A 
study by Nachtigall and Supin (2018) showed that false killer whales 
adjust their hearing to compensate for ambient sounds and the intensity 
of returning echolocation signals.
    Impacts on signal detection, measured by masked detection 
thresholds, are not the only important factors to address when 
considering the potential effects of masking. As marine mammals use 
sound to recognize conspecifics, prey, predators, or other biologically 
significant sources (Branstetter et al., 2016), it is also important to 
understand the impacts of masked recognition thresholds (informational 
masking). Branstetter et al. (2016) measured masked recognition 
thresholds for whistle-like sounds of bottlenose dolphins and observed 
that they are approximately 4 dB above detection thresholds (energetic 
masking) for the same signals. Reduced ability to recognize a 
conspecific call or the acoustic signature of a predator could have 
severe negative impacts. Branstetter et al. (2016) observed that if 
``quality communication'' is set at 90 percent recognition the output 
of communication space models (which are based on 50 percent detection) 
would likely result in a significant decrease in communication range.
    As marine mammals use sound to recognize predators (Allen et al., 
2014; Cummings and Thompson, 1971; Cure, et al., 2015; Fish and Vania, 
1971), the presence of masking noise may also prevent marine mammals 
from responding to acoustic cues produced by their predators, 
particularly if it occurs in the same frequency band. For example, 
harbor seals that reside in the coastal waters of British Columbia are 
frequently targeted by mammal-eating killer whales. The seals 
acoustically discriminate between the calls of mammal-eating and fish-
eating killer whales (Deecke et al., 2002), a capability that should 
increase survivorship while reducing the energy required to identify 
all killer whale calls. Similarly, sperm whales (Cure, et al., 2016; 
Isojunno et al., 2016), long-finned pilot whales (Visser et al., 2016), 
and humpback whales (Cure, et al., 2015) changed their behavior in 
response to killer whale vocalization playbacks. The potential effects 
of masked predator acoustic cues depends on the duration of the masking 
noise and the likelihood of a marine mammal encountering a predator 
during the time that detection and recognition of predator cues are 
impeded.
    Redundancy and context can also facilitate detection of weak 
signals. These phenomena may help marine mammals detect weak sounds in 
the presence of natural or anthropogenic noise. Most masking studies in 
marine mammals present the test signal and the masking noise from the 
same direction. The dominant background noise may be highly directional 
if it comes from a particular anthropogenic source such as a vessel or 
industrial site. Directional hearing may significantly reduce the 
masking effects of these sounds by improving the effective signal-to-
noise ratio.
    Masking affects both senders and receivers of acoustic signals and 
can potentially have long-term chronic effects on marine mammals at the 
population level as well as at the individual level. Low-frequency 
ambient sound levels have increased by as much as 20 dB (more than 
three times in terms of SPL) in the world's ocean from pre-industrial 
periods, with most of the increase from distant commercial shipping 
(Hildebrand, 2009; Cholewiak et al., 2018). All anthropogenic sound 
sources, but especially chronic and lower-frequency signals (e.g., from 
commercial vessel traffic), contribute to elevated ambient sound 
levels, thus intensifying masking for marine mammals.
Masking Due to Sonar and Other Transducers--
    The functional hearing ranges of mysticetes, odontocetes, and 
pinnipeds underwater overlap the frequencies of the sonar sources used 
in the Action Proponents' LFAS/MFAS/high-frequency active sonar (HFAS) 
training and the Navy's testing exercises. Additionally, almost all 
affected species' vocal repertoires span across the frequencies of 
these sonar sources used by the Action Proponents. The closer the 
characteristics of the masking signal to the signal of interest, the 
more likely masking is to occur. Masking by LFAS or MFAS with 
relatively low-duty cycles is not anticipated (or would be of very 
short duration) for most cetaceans as sonar signals occur over a 
relatively short duration and narrow bandwidth (overlapping with only a 
small portion of the hearing range). LFAS could overlap in frequency 
with mysticete vocalizations, however LFAS does not overlap with 
vocalizations for most marine mammal species. For example, in the 
presence of LFAS, humpback whales were observed to increase the length 
of their songs (Fristrup et al., 2003; Miller et al., 2000), 
potentially

[[Page 19928]]

due to the overlap in frequencies between the whale song and the LFAS. 
While dolphin whistles and MFAS are similar in frequency, masking is 
not anticipated (or would be of very short duration) due to the low-
duty cycle and short durations of most sonars.
    As described in additional detail in the 2024 AFTT Draft 
Supplemental EIS/OEIS, high duty-cycle or CAS have more potential to 
mask vocalizations. These sonars transmit more frequently (greater than 
80 percent duty cycle) than traditional sonars, but typically at lower 
source levels. HFAS, such as pingers that operate at higher repetition 
rates, also operate at lower source levels and have faster attenuation 
rates due to the higher frequencies used. These lower source levels 
limit the range of impacts, however, compared to traditional sonar 
systems, individuals close to the source are likely to experience 
masking at longer time scales. The frequency range at which high-duty 
cycle systems operate overlaps the vocalization frequency of many mid-
frequency cetaceans. Continuous noise at the same frequency of 
communicative vocalizations may cause disruptions to communication, 
social interactions, and acoustically mediated cooperative behaviors 
(S[oslash]rensen et al., 2023) such as foraging and mating. Similarly, 
because the high-duty cycle or CAS includes mid-frequency sources, 
there is also the potential for the mid-frequency sonar signals to mask 
important environmental cues (e.g., predator or conspecific acoustic 
cues), possibly affecting survivorship for targeted animals. Spatial 
release from masking may occur with higher duty cycle or CAS.
    While there are currently few studies of the impacts of high-duty 
cycle sonars on marine mammals, masking due to these systems is likely 
analogous to masking produced by other continuous sources (e.g., vessel 
noise and low-frequency cetaceans), and would likely have similar 
short-term consequences, though longer in duration due to the duration 
of the masking noise. These may include changes to vocalization 
amplitude and frequency (Brumm and Slabbekoorn, 2005; Hotchkin and 
Parks, 2013) and behavioral impacts such as avoidance of the area and 
interruptions to foraging or other essential behaviors (Gordon et al., 
2003). Long-term consequences could include changes to vocal behavior 
and vocalization structure (Foote et al., 2004; Parks et al., 2007), 
abandonment of habitat if masking occurs frequently enough to 
significantly impair communication (Brumm and Slabbekoorn, 2005), a 
potential decrease in survivorship if predator vocalizations are masked 
(Brumm and Slabbekoorn, 2005), and a potential decrease in recruitment 
if masking interferes with reproductive activities or mother-calf 
communication (Gordon et al., 2003).
    von Benda-Beckmann et al. (2021) modeled the effect of pulsed and 
continuous 1 to 2 kHz active sonar on sperm whale echolocation clicks 
and found that the presence of upper harmonics in the sonar signal 
increased masking of clicks produced in the search phase of foraging 
compared to buzz clicks produced during prey capture. Different levels 
of sonar caused intermittent to continuous masking (120 to 160 dB re 1 
[micro]Pa\2\, respectively), but varied based on click level, whale 
orientation, and prey target strength. CAS resulted in a greater 
percentage of time that echolocation clicks were masked compared to 
pulsed active sonar. This means that sonar sounds could reduce the 
ability of sperm whales to find prey under certain conditions. However, 
echoes from prey are most likely spatially separated from the sonar 
source, and so spatial release from masking would be expected.
Masking Due to Impulsive Noise--
    Impulsive sound sources, including explosions, are intense and 
short in duration. Since impulsive noise is intermittent, the length of 
the gap between sounds (duty-cycle) and received level are relevant 
when considering the potential for masking. Impulsive sounds with lower 
duty cycles or lower received levels are less likely to result in 
masking than higher duty cycles or received levels. There are no direct 
observations of masking in marine mammals due to exposure to explosive 
sources. Potential masking from explosive sounds or weapon noise is 
likely similar to masking studied for other impulsive sounds, such as 
air guns or pile-driving.
    Masking of mysticete calls could occur due to the overlap between 
their low-frequency vocalizations and the dominant frequencies of 
impulsive sources (Castellote et al., 2012; Nieukirk et al., 2012). For 
example, blue whale feeding/social calls increased when seismic 
exploration was underway (Di Lorio & Clark, 2010), indicative of a 
possible compensatory response to masking effects of the increased 
noise level. However, mysticetes that call at higher rates are less 
likely to be masked by impulsive noise with lower duty cycles (Clark et 
al., 2009) because of the decreased likelihood that the noise would 
overlap with the calls, and because of dip listening. Field 
observations of masking effects such as vocal modifications are 
difficult to interpret because when recordings indicate that call rates 
decline, this could be caused by (1) animals calling less frequently 
(actual noise-induced vocal modifications), (2) the calls being masked 
from the recording hydrophone due to the noise (e.g., animals are not 
calling less frequently but are being detected less frequently), or (3) 
the animals moving away from the noise, or any combination of these 
causes (Blackwell et al., 2013; Cerchio et al., 2014).
    Masking of pinniped communication sounds at 100 Hz center frequency 
is possible when vocalizations occur at the same time as an air gun 
pulse (Sills et al., 2017). This might result in some percentage of 
vocalizations being masked if an activity such as a seismic survey is 
being conducted in the vicinity, even when the sender and receiver are 
near one another. Release from masking due to ``dip listening'' is 
likely in this scenario.
    While a masking effect of impulsive noise can depend on the 
received level (Blackwell et al., 2015) and other characteristics of 
the noise, the vocal response of the affected animal to masking noise 
is an equally important consideration for inferring overall impacts to 
an animal. It is possible that the receiver would increase the rate 
and/or level of calls to compensate for masking; or, conversely, cease 
calling.
    In general, impulsive noise has the potential to mask sounds that 
are biologically important for marine mammals, reducing communication 
space or resulting in noise-induced vocal modifications that might 
impact marine mammals. Masking by close-range impulsive sound sources 
is most likely to impact marine mammal communication.
Masking Due to Vessel Noise--
    Masking is more likely to occur in the presence of broadband, 
relatively continuous noise sources such as vessels. Several studies 
have shown decreases in marine mammal communication space and changes 
in behavior as a result of the presence of vessel noise. For example, 
NARW were observed to shift the frequency content of their calls upward 
while reducing the rate of calling in areas of increased anthropogenic 
noise (Parks et al., 2007) as well as increasing the amplitude 
(intensity) of their calls (Parks, 2009; Parks et al., 2011). Fournet 
et al. (2018) observed that humpback whales in Alaska responded to 
increasing ambient sound levels (natural and anthropogenic) by 
increasing the source levels of their calls (non-song

[[Page 19929]]

vocalizations). Clark et al. (2009) also observed that right whales 
communication space decreased by up to 84 percent in the presence of 
vessels (Clark et al., 2009). Cholewiak et al. (2018) also observed 
loss in communication space in Stellwagen National Marine Sanctuary for 
NARW, fin whales, and humpback whales with increased ambient noise and 
shipping noise. Gabriele et al. (2018) modeled the effects of vessel 
traffic sound on communication space in Glacier Bay National Park in 
Alaska and found that typical summer vessel traffic in the Park causes 
losses of communication space to singing whales (reduced by 13-28 
percent), calling whales (18-51 percent), and roaring seals (32-61 
percent), particularly during daylight hours and even in the absence of 
cruise ships. Dunlop (2019) observed that an increase in vessel noise 
reduced modeled communication space and resulted in significant 
reduction in group social interactions in Australian humpback whales. 
However, communication signal masking did not fully explain this change 
in social behavior in the model, indicating there may also be an 
additional effect of the physical presence of the vessel on social 
behavior (Dunlop, 2019). Although humpback whales off Australia did not 
change the frequency or duration of their vocalizations in the presence 
of ship noise, their source levels were lower than expected based on 
source level changes to wind noise, potentially indicating some signal 
masking (Dunlop, 2016). Multiple delphinid species have also been shown 
to increase the minimum or maximum frequencies of their whistles in the 
presence of anthropogenic noise and reduced communication space (e.g., 
Holt et al., 2009; Holt et al., 2011; Gervaise et al., 2012; Williams 
et al., 2013; Hermannsen et al., 2014; Papale et al., 2015; Liu et al., 
2017).
Other Physiological Response
    Physiological stress is a natural and adaptive process that helps 
an animal survive changing conditions. When an animal perceives a 
potential threat, whether or not the stimulus actually poses a threat, 
a stress response is triggered (Seyle, 1950; Moberg, 2000; Sapolsky et 
al., 2005). Once an animal's central nervous system perceives a threat, 
it mounts a biological response or defense that consists of a 
combination of behavioral responses, autonomic nervous system 
responses, neuroendocrine responses, or immune responses.
    The primary distinction between stress (which is adaptive and does 
not normally place an animal at risk) and distress is the biotic cost 
of the response. During a stress response, an animal uses glycogen 
stores that can be quickly replenished once the stress is alleviated. 
In such circumstances, the cost of the stress response would not pose 
serious fitness consequences. However, when an animal does not have 
sufficient energy reserves to satisfy the energetic costs of a stress 
response, energy resources must be diverted from other biotic 
functions. For example, when a stress response diverts energy away from 
growth in young animals, those animals may experience stunted growth. 
When a stress response diverts energy from a fetus, an animal's 
reproductive success and its fitness will suffer. In these cases, the 
animals will have entered a pre-pathological or pathological state 
which is called ``distress'' (Seyle, 1950) or ``allostatic loading'' 
(McEwen and Wingfield, 2003). This pathological state of distress will 
last until the animal replenishes its energetic reserves sufficiently 
to restore normal function.
    According to Moberg (2000), in the case of many stressors, an 
animal's first and sometimes most economical (in terms of biotic costs) 
response is behavioral avoidance of the potential stressor or avoidance 
of continued exposure to a stressor. An animal's second line of defense 
to stressors involves the sympathetic part of the autonomic nervous 
system and the classical ``fight or flight'' response which includes 
the cardiovascular system, the gastrointestinal system, the exocrine 
glands, and the adrenal medulla to produce changes in heart rate, blood 
pressure, and gastrointestinal activity that humans commonly associate 
with ``stress.'' These responses have a relatively short duration and 
may or may not have significant long-term effect on an animal's 
welfare.
    An animal's third line of defense to stressors involves its 
neuroendocrine systems or sympathetic nervous systems; the system that 
has received the most study has been the hypothalamus-pituitary-adrenal 
system (also known as the HPA axis in mammals or the hypothalamus-
pituitary-interrenal axis in fish and some reptiles). Unlike stress 
responses associated with the autonomic nervous system, virtually all 
neuro-endocrine functions that are affected by stress, including immune 
competence, reproduction, metabolism, and behavior, are regulated by 
pituitary hormones. Stress-induced changes in the secretion of 
pituitary hormones have been implicated in failed reproduction (Moberg, 
1987; Rivier and Rivest, 1991), altered metabolism (Elasser et al., 
2000), reduced immune competence (Blecha, 2000), and behavioral 
disturbance (Moberg, 1987; Blecha, 2000). Increases in the circulation 
of glucocorticosteroids (cortisol, corticosterone, and aldosterone in 
marine mammals; see Romano et al., 2004) have been equated with stress 
for many years.
    Marine mammals naturally experience stressors within their 
environment and as part of their life histories. Changing weather and 
ocean conditions, exposure to disease and naturally occurring toxins, 
lack of prey availability, and interactions with predators all 
contribute to the stress a marine mammal experiences (Atkinson et al., 
2015). Breeding cycles, periods of fasting, social interactions with 
members of the same species, and molting (for pinnipeds) are also 
stressors, although they are natural components of an animal's life 
history. Anthropogenic activities have the potential to provide 
additional stressors beyond those that occur naturally (e.g., fishery 
interactions, pollution, tourism, ocean noise) (Fair et al., 2014; 
Meissner et al., 2015; Rolland et al., 2012).
    Relationships between these physiological mechanisms, animal 
behavior, and the costs of stress responses are well-studied through 
controlled experiments for both laboratory and free-ranging animals 
(e.g., Holberton et al., 1996; Hood et al., 1998; Jessop et al., 2003; 
Krausman et al., 2004; Lankford et al., 2005; Reneerkens et al., 2002; 
Thompson and Hamer, 2000). However, it should be noted (and as is 
described in additional detail in the 2024 AFTT Draft Supplemental EIS/
OEIS) that our understanding of the functions of various stress 
hormones (e.g., cortisol), is based largely upon observations of the 
stress response in terrestrial mammals. Atkinson et al., (2015) note 
that the endocrine response of marine mammals to stress may not be the 
same as that of terrestrial mammals because of the selective pressures 
marine mammals faced during their evolution in an ocean environment. 
For example, due to the necessity of breath-holding while diving and 
foraging at depth, the physiological role of epinephrine and 
norepinephrine (the catecholamines) in marine mammals might be 
different than in other mammals. Relatively little information exists 
on the linkage between anthropogenic sound exposure and stress in 
marine mammals, and even less information exists on the ultimate 
consequences of sound-induced stress responses (either acute or 
chronic). Most studies to date have focused on acute responses to sound

[[Page 19930]]

either by measuring neurohormones (i.e., catecholamines) or heart rate 
as a proxy for an acute stress response.
    The ability to make predictions from stress hormones about impacts 
on individuals and populations exposed to various forms of natural and 
anthropogenic stressors relies on understanding the linkages between 
changes in stress hormones and resulting physiological impacts. 
Currently, the sound characteristics that correlate with specific 
stress responses in marine mammals are poorly understood, as are the 
ultimate consequences of these changes. Several research efforts have 
improved the understanding of, and the ability to predict, how 
stressors ultimately affect marine mammal populations (e.g., King et 
al., 2015; New et al., 2013a; Pirotta et al., 2015a; Pirotta et al., 
2022b). This includes determining how and to what degree various types 
of anthropogenic sound cause stress in marine mammals and understanding 
what factors may mitigate those physiological stress responses. Factors 
potentially affecting an animal's response to a stressor include life 
history, sex, age, reproductive status, overall physiological and 
behavioral adaptability, and whether they are na[iuml]ve or experienced 
with the sound (e.g., prior experience with a stressor may result in a 
reduced response due to habituation)(Finneran and Branstetter, 2013; 
St. Aubin and Dierauf, 2001). Because there are many unknowns regarding 
the occurrence of acoustically induced stress responses in marine 
mammals, any physiological response (e.g., hearing loss or injury) or 
significant behavioral response is assumed to be associated with a 
stress response.
    Non-impulsive sources of sound can cause direct physiological 
effects including noise-induced loss of hearing sensitivity (or 
``threshold shift'') or other auditory injury, nitrogen decompression, 
acoustically-induced bubble growth, and injury due to sound-induced 
acoustic resonance. Separately, an animal's behavioral response to an 
acoustic exposure might lead to physiological effects that might 
ultimately lead to injury or death, which is discussed later in the 
Stranding and Mortality section.
Heart Rate Response--
    Several experimental studies have measured the heart rate response 
of a variety of marine mammals. For example, Miksis et al. (2001) 
observed increases in heart rates of captive bottlenose dolphins to 
which known calls of other dolphins were played, although no increase 
in heart rate was observed when background tank noise was played back. 
However, it cannot be determined whether the increase in heart rate was 
due to stress or social factors, such as expectation of an encounter 
with a known conspecific. Similarly, a young captive beluga's heart 
rate increased during exposure to noise, with increases dependent upon 
the frequency band of noise and duration of exposure, and with a sharp 
decrease to normal or below normal levels upon cessation of the 
exposure (Lyamin et al., 2011). Spectral analysis of heart rate 
variability corroborated direct measures of heart rate (Bakhchina et 
al., 2017). This response might have been in part due to the conditions 
during testing, the young age of the animal, and the novelty of the 
exposure; a year later the exposure was repeated at a slightly higher 
received level and there was no heart rate response, indicating the 
beluga whale had potentially habituated to the noise exposure.
    Kvadsheim et al. (2010a) measured the heart rate of captive hooded 
seals during exposure to sonar signals and found an increase in the 
heart rate of the seals during exposure periods versus control periods 
when the animals were at the surface. When the animals dove, the normal 
dive-related heart rate decrease was not impacted by the sonar 
exposure. Similarly, Thompson et al. (1998) observed a rapid, short-
lived decrease in heart rates in wild harbor and grey seals exposed to 
seismic air guns (cited in Gordon et al., 2003).
    Two captive harbor porpoises showed significant bradycardia 
(reduced heart rate), below that which occurs with diving, when they 
were exposed to pinger-like sounds with frequencies between 100-140 kHz 
(Teilmann et al., 2006). The bradycardia was found only in the early 
noise exposures and the porpoises acclimated quickly across successive 
noise exposures. Elmegaard et al. (2021) also found that initial 
exposures to sonar sweeps produced bradycardia but did not elicit a 
startle response in captive harbor porpoises. As with Teilmann et al. 
(2006), the cardiac response disappeared over several repeat exposures 
suggesting rapid acclimation to the noise. In the same animals, 40-kHz 
noise pulses induced startle responses but without a change in heart 
rate. Bakkeren et al. (2023) found no change in the heart rate of a 
harbor porpoise during exposure to masking noise (\1/3\ octave band 
noise, centered frequency of 125 kHz, maximum received level of 125 dB 
re 1 [mu]Pa) during an echolocation task but showed significant 
bradycardia while blindfolded for the same task. The authors attributed 
the change in heart rate to sensory deprivation, although no strong 
conclusions about acoustic masking could be made since the animal was 
still able to perform the echolocation task in the presence of the 
masking noise. Williams et al. (2022) observed periods of increased 
heart rate variability in narwhals during seismic air gun impulse 
exposure, but profound bradycardia was not noted. Conversely, Williams 
et al. (2017) found that a profound bradycardia persisted in narwhals, 
even though exercise effort increased dramatically as part of their 
escape response following release from capture and handling.
    Limited evidence across several different species suggests that 
increased heart rate might occur as part of the acute stress response 
of marine mammals that are at the surface. However, the decreased heart 
rate typical of diving marine mammals can be enhanced in response to an 
acute stressor, suggesting that the context of the exposure is critical 
to understanding the cardiac response. Furthermore, in instances where 
a cardiac response was noted, there appears to be rapid habituation 
when repeat exposures occur. Additional research is required to 
understand the interaction of dive bradycardia, noise-induced cardiac 
responses, and the role of habituation in marine mammals.
Stress Hormone and Immune Response--
    What is known about the function of the various stress hormones is 
based largely upon observations of the stress response in terrestrial 
mammals. The endocrine response of marine mammals to stress may not be 
the same as that of terrestrial mammals because of the selective 
pressures marine mammals faced during their evolution in an ocean 
environment (Atkinson et al., 2015). For example, due to the necessity 
of breath-holding while diving and foraging at depth, the physiological 
role of epinephrine and norepinephrine (the catecholamines) might be 
different in marine versus other mammals.
    Catecholamines increase during breath-hold diving in seals, co-
occurring with a reduction in heart rate, peripheral vasoconstriction 
(constriction of blood vessels), and an increased reliance on anaerobic 
metabolism during extended dives (Hance et al., 1982; Hochachka et al., 
1995; Hurford et al., 1996); the catecholamine increase is not 
associated with increased heart rate, glycemic release, and increased 
oxygen consumption typical of terrestrial mammals. Captive belugas

[[Page 19931]]

demonstrated no catecholamine response to the playback of oil drilling 
sounds (Thomas et al., 1990b) but showed a small but statistically 
significant increase in catecholamines following exposure to impulsive 
sounds produced from a seismic water gun (Romano et al., 2004). A 
captive bottlenose dolphin exposed to the same sounds did not 
demonstrate a catecholamine response but did demonstrate a 
statistically significant elevation in aldosterone (Romano et al., 
2004); however, the increase was within the normal daily variation 
observed in this species (St. Aubin et al., 1996) and was likely of 
little biological significance. Aldosterone has been speculated to not 
only contribute to electrolyte balance, but possibly also the 
maintenance of blood pressure during periods of vasoconstriction 
(Houser et al., 2011). In marine mammals, aldosterone is thought to 
play a role in mediating stress (St. Aubin & Dierauf, 2001; St. Aubin & 
Geraci, 1989).
    Yang et al. (2021) measured cortisol concentrations in two captive 
bottlenose dolphins and found significantly higher concentrations after 
exposure to 140 dB re 1 [mu]Pa impulsive noise playbacks. Two out of 
six tested indicators of immune system function underwent acoustic 
dose-dependent changes, suggesting that repeated exposures or sustained 
stress response to impulsive sounds may increase an affected 
individual's susceptibility to pathogens. Unfortunately, absolute 
values of cortisol were not provided, and it is not possible from the 
study to tell if cortisol rose to problematic levels (e.g., see normal 
variation and changes due to handling in Houser et al. (2021) and 
Champagne et al. (2018)). Exposing dolphins to a different acoustic 
stressor yielded contrasting results. Houser et al. (2020) measured 
cortisol and epinephrine obtained from 30 captive bottlenose dolphins 
exposed to simulated Navy MFAS and found no correlation between SPL and 
stress hormone levels, even though sound exposures were as high as 185 
dB re 1 [mu]Pa. In the same experiment (Houser et al., 2013b), 
behavioral responses were shown to increase in severity with increasing 
received SPLs. These results suggest that behavioral responses to sonar 
signals are not necessarily indicative of a hormonal stress response.
    Whereas a limited amount of work has addressed the potential for 
acute sound exposures to produce a stress response, almost nothing is 
known about how chronic exposure to acoustic stressors affects stress 
hormones in marine mammals, particularly as it relates to survival or 
reproduction. In what is probably the only study of chronic noise 
exposure in marine mammals associating changes in a stress hormone with 
changes in anthropogenic noise, Rolland et al. (2012) compared the 
levels of cortisol metabolites in NARW feces collected before and after 
September 11, 2001. Following the events of September 11, 2001, 
shipping was significantly reduced in the region where fecal 
collections were made, and regional ocean background noise declined. 
Fecal cortisol metabolites significantly decreased during the period of 
reduced ship traffic and ocean noise (Rolland et al., 2012). Rolland et 
al. (2017) also compared acute (death by vessel strike) to chronic 
(entanglement or live stranding) stressors in NARW and found that 
whales subject to chronic stressors had higher levels of glucocorticoid 
stress hormones (cortisol and corticosterone) than either healthy 
whales or those killed by ships. It was presumed that whales subjected 
to acute stress may have died too quickly for increases in fecal 
glucocorticoids to be detected.
    Considerably more work has been conducted in an attempt to 
determine the potential effect of vessel disturbance on smaller 
cetaceans, particularly killer whales (Bain, 2002; Erbe, 2002; Lusseau, 
2006; Noren et al., 2009; Pirotta et al., 2015b; Read et al., 2014; 
Rolland et al., 2012; Williams et al., 2009; Williams et al., 2014a; 
Williams et al., 2014b; Williams et al., 2006b). Most of these efforts 
focused primarily on estimates of metabolic costs associated with 
altered behavior or inferred consequences of boat presence and noise 
but did not directly measure stress hormones. However, Ayres et al. 
(2012) investigated Southern Resident killer whale fecal thyroid 
hormone and cortisol metabolites to assess two potential threats to the 
species' recovery: lack of prey (salmon) and impacts from exposure to 
the physical presence of vessel traffic (but without measuring vessel 
traffic noise). Ayres et al. (2012) concluded from these stress hormone 
measures that the lack of prey overshadowed any population-level 
physiological impacts on Southern Resident killer whales due to vessel 
traffic. Lemos et al. (2022) investigated the potential for vessel 
traffic to affect gray whales. By assessing gray whale fecal cortisol 
metabolites across years in which vessel traffic was variable, Lemos et 
al. (2022) found a direct relationship between the presence/density of 
vessel traffic and fecal cortisol metabolite levels. Unfortunately, no 
direct noise exposure measurements were made on any individual making 
it impossible to tell if other natural and anthropogenic factors could 
also be related to the results. Collectively, these studies indicate 
the difficulty in determining which factors are primarily influence the 
secretion of stress hormones, including the separate and additive 
effects of vessel presence and vessel noise. While vessel presence 
could contribute to the variation in fecal cortisol metabolites in NARW 
and gray whales, there are other potential influences on fecal hormone 
metabolites, so it is difficult to establish a direct link between 
ocean noise and fecal hormone metabolites.
Non-Auditory Injury
    Non-auditory injury, or direct injury, is considered less likely to 
occur in the context of the Action Proponents' activities than auditory 
injury and the primary anticipated source of non-auditory injury for 
these activities is exposure to the pressure generated by explosive 
detonations, which is discussed in the Potential Effects of Explosive 
Sources on Marine Mammals section below. Here, we discuss less direct 
non-auditory injury impacts, including acoustically induced bubble 
formation, injury from sonar-induced acoustic resonance, and 
behaviorally mediated injury.
    One theoretical cause of injury to marine mammals is rectified 
diffusion (Crum and Mao, 1996), the process of increasing the size of a 
bubble by exposing it to a sound field. This process could be 
facilitated if the environment in which the ensonified bubbles exist is 
supersaturated with gas. Repetitive diving by marine mammals can cause 
the blood and some tissues to accumulate gas to a greater degree than 
is supported by the surrounding environmental pressure (Ridgway and 
Howard, 1979). The deeper and longer dives of some marine mammals (for 
example, beaked whales) are theoretically predicted to induce greater 
supersaturation (Houser et al., 2001b). If rectified diffusion were 
possible in marine mammals exposed to high-level sound, conditions of 
tissue supersaturation could theoretically speed the rate and increase 
the size of bubble growth. Subsequent effects due to tissue trauma and 
emboli would presumably mirror those observed in humans suffering from 
decompression sickness. Acoustically-induced (or mediated) bubble 
growth and other pressure-related physiological impacts are addressed 
below but are not expected to result from the Action Proponents' 
proposed activities.

[[Page 19932]]

    It is unlikely that the short duration (in combination with the 
source levels) of sonar pings would be long enough to drive bubble 
growth to any substantial size, if such a phenomenon occurs. However, 
an alternative but related hypothesis has also been suggested: stable 
bubbles could be destabilized by high-level sound exposures such that 
bubble growth then occurs through static diffusion of gas out of the 
tissues. In such a scenario the marine mammal would need to be in a 
gas-supersaturated state for a long enough period of time for bubbles 
to become of a problematic size. Recent research with ex vivo 
supersaturated bovine tissues suggested that, for a 37 kHz signal, a 
sound exposure of approximately 215 dB referenced to (re) 1 [mu]Pa 
would be required before microbubbles became destabilized and grew 
(Crum et al., 2005). Assuming spherical spreading loss and a nominal 
sonar source level of 235 dB re 1 [mu]Pa at 1 m, a whale would need to 
be within 33 ft (10 m) of the sonar dome to be exposed to such sound 
levels. Furthermore, tissues in the study were supersaturated by 
exposing them to pressures of 400-700 kilopascals for periods of hours 
and then releasing them to ambient pressures. Assuming the 
equilibration of gases with the tissues occurred when the tissues were 
exposed to the high pressures, levels of supersaturation in the tissues 
could have been as high as 400-700 percent. These levels of tissue 
supersaturation are substantially higher than model predictions for 
marine mammals (Fahlman et al., 2009; Fahlman et al., 2014; Houser et 
al., 2001; Saunders et al., 2008). It is improbable that this mechanism 
is responsible for stranding events or traumas associated with beaked 
whale strandings because both the degree of supersaturation and 
exposure levels observed to cause microbubble destabilization are 
unlikely to occur, either alone or in concert.
    Yet another hypothesis (decompression sickness) has speculated that 
rapid ascent to the surface following exposure to a startling sound 
might produce tissue gas saturation sufficient for the evolution of 
nitrogen bubbles (Jepson et al., 2003; Fernandez et al., 2005; 
Fern[aacute]ndez et al., 2012). In this scenario, the rate of ascent 
would need to be sufficiently rapid to compromise behavioral or 
physiological protections against nitrogen bubble formation. 
Alternatively, Tyack et al. (2006) studied the deep diving behavior of 
beaked whales and concluded that: ``Using current models of breath-hold 
diving, we infer that their natural diving behavior is inconsistent 
with known problems of acute nitrogen supersaturation and embolism.'' 
Collectively, these hypotheses can be referred to as ``hypotheses of 
acoustically mediated bubble growth.''
    Although theoretical predictions suggest the possibility for 
acoustically mediated bubble growth, there is considerable disagreement 
among scientists as to its likelihood (Piantadosi and Thalmann, 2004; 
Evans and Miller, 2003; Cox et al., 2006; Rommel et al., 2006). Crum 
and Mao (1996) hypothesized that received levels would have to exceed 
190 dB in order for there to be the possibility of significant bubble 
growth due to supersaturation of gases in the blood (i.e., rectified 
diffusion). Work conducted by Crum et al. (2005) demonstrated the 
possibility of rectified diffusion for short duration signals, but at 
SELs and tissue saturation levels that are highly improbable to occur 
in diving marine mammals. To date, energy levels predicted to cause in 
vivo bubble formation within diving cetaceans have not been evaluated 
(NOAA, 2002b). Jepson et al. (2003, 2005) and Fernandez et al. (2004, 
2005, 2012) concluded that in vivo bubble formation, which may be 
exacerbated by deep, long-duration, repetitive dives may explain why 
beaked whales appear to be relatively vulnerable to MFAS/HFAS 
exposures. It has also been argued that traumas from some beaked whale 
strandings are consistent with gas emboli and bubble-induced tissue 
separations (Jepson et al., 2003); however, there is no conclusive 
evidence of this (Rommel et al., 2006). Based on examination of sonar-
associated strandings, Bernaldo de Quiros et al. (2019) list diagnostic 
features, the presence of all of which suggest gas and fat embolic 
syndrome for beaked whales stranded in association with sonar exposure.
    As described in additional detail in the Behaviorally Mediated 
Injury section of appendix D the 2024 AFTT Draft Supplemental EIS/OEIS, 
marine mammals generally are thought to deal with nitrogen loads in 
their blood and other tissues, caused by gas exchange from the lungs 
under conditions of high ambient pressure during diving, through 
anatomical, behavioral, and physiological adaptations (Hooker et al., 
2012). Although not a direct injury, variations in marine mammal diving 
behavior or avoidance responses have been hypothesized to result in 
nitrogen off-gassing in super-saturated tissues, possibly to the point 
of deleterious vascular and tissue bubble formation (Hooker et al., 
2012; Jepson et al., 2003; Saunders et al., 2008) with resulting 
symptoms similar to decompression sickness, however the process is 
still not well understood.
    In 2009, Hooker et al. tested two mathematical models to predict 
blood and tissue tension N2 (PN2) using field data from 
three beaked whale species: northern bottlenose whales, goose-beaked 
whales, and Blainville's beaked whales. The researchers aimed to 
determine if physiology (body mass, diving lung volume, and dive 
response) or dive behavior (dive depth and duration, changes in ascent 
rate, and diel behavior) would lead to differences in PN2 
levels and thereby decompression sickness risk between species. In 
their study, they compared results for previously published time depth 
recorder data (Hooker and Baird, 1999; Baird et al., 2006, 2008) from 
goose-beaked whale, Blainville's beaked whale, and northern bottlenose 
whale. They reported that diving lung volume and extent of the dive 
response had a large effect on end-dive PN2. Also, results 
showed that dive profiles had a larger influence on end-dive 
PN2 than body mass differences between species. Despite diel 
changes (i.e., variation that occurs regularly every day or most days) 
in dive behavior, PN2 levels showed no consistent trend. 
Model output suggested that all three species live with tissue 
PN2 levels that would cause a significant proportion of 
decompression sickness cases in terrestrial mammals. The authors 
concluded that the dive behavior of goose-beaked whale was different 
from both Blainville's beaked whale and northern bottlenose whale, and 
resulted in higher predicted tissue and blood N2 levels (Hooker et al., 
2009). They also suggested that the prevalence of goose-beaked whales 
stranding after naval sonar exercises could be explained by either a 
higher abundance of this species in the affected areas or by possible 
species differences in behavior and/or physiology related to MF active 
sonar (Hooker et al., 2009).
    Bernaldo de Quiros et al. (2012) showed that, among stranded 
whales, deep diving species of whales had higher abundances of gas 
bubbles compared to shallow diving species. Kvadsheim et al. (2012) 
estimated blood and tissue PN2 levels in species 
representing shallow, intermediate, and deep diving cetaceans following 
behavioral responses to sonar and their comparisons found that deep 
diving species had higher end-dive blood and tissue N2 levels, 
indicating a higher risk of developing gas bubble emboli compared with 
shallow diving species. Fahlmann et al. (2014) evaluated dive data 
recorded from sperm, killer, long-finned pilot, Blainville's, and 
goose-beaked whales before and during

[[Page 19933]]

exposure to low-frequency (1-2 kHz), as defined by the authors, and 
mid-frequency (2-7 kHz) active sonar in an attempt to determine if 
either differences in dive behavior or physiological responses to sonar 
are plausible risk factors for bubble formation. The authors suggested 
that CO2 may initiate bubble formation and growth, while 
elevated levels of N2 may be important for continued bubble growth. The 
authors also suggest that if CO2 plays an important role in 
bubble formation, a cetacean escaping a sound source may experience 
increased metabolic rate, CO2 production, and alteration in 
cardiac output, which could increase risk of gas bubble emboli. 
However, as discussed in Kvadsheim et al. (2012), the actual observed 
behavioral responses to sonar from the species in their study (sperm, 
killer, long-finned pilot, Blainville's beaked, and goose-beaked 
whales) did not imply any significantly increased risk of decompression 
sickness due to high levels of N2. Therefore, further information is 
needed to understand the relationship between exposure to stimuli, 
behavioral response (discussed in more detail below), elevated N2 
levels, and gas bubble emboli in marine mammals. The hypotheses for gas 
bubble formation related to beaked whale strandings is that beaked 
whales potentially have strong avoidance responses to MFAS because they 
sound similar to their main predator, the killer whale (Cox et al., 
2006; Southall et al., 2007; Zimmer and Tyack, 2007; Baird et al., 
2008; Hooker et al., 2009). Further investigation is needed to assess 
the potential validity of these hypotheses.
    To summarize, while there are several hypotheses, there is little 
data directly connecting intense, anthropogenic underwater sounds with 
non-auditory physical effects in marine mammals. The available data do 
not support identification of a specific exposure level above which 
non-auditory effects can be expected (Southall et al., 2007) or any 
meaningful quantitative predictions of the numbers (if any) of marine 
mammals that might be affected in these ways. In addition, such 
effects, if they occur at all, would be expected to be limited to 
situations where marine mammals were exposed to high powered sounds at 
very close range over a prolonged period of time, which is not expected 
to occur based on the speed of the vessels operating sonar in 
combination with the speed and behavior of marine mammals in the 
vicinity of sonar.
    An object exposed to its resonant frequency will tend to amplify 
its vibration at that frequency, a phenomenon called acoustic 
resonance. Acoustic resonance has been proposed as a potential 
mechanism by which a sonar or sources with similar operating 
characteristics could damage tissues of marine mammals. In 2002, NMFS 
convened a panel of government and private scientists to investigate 
the potential for acoustic resonance to occur in marine mammals (NOAA, 
2002). They modeled and evaluated the likelihood that Navy MFAS (2-10 
kHz) caused resonance effects in beaked whales that eventually led to 
their stranding. The workshop participants concluded that resonance in 
air-filled structures was not likely to have played a primary role in 
the Bahamas stranding in 2000. They listed several reasons supporting 
this finding including (among others): tissue displacements at 
resonance are estimated to be too small to cause tissue damage (i.e., 
non-auditory injury); tissue-lined air spaces most susceptible to 
resonance are too large in marine mammals to have resonant frequencies 
in the ranges used by MFAS or LFAS; lung resonant frequencies increase 
with depth, and tissue displacements decrease with depth so if 
resonance is more likely to be caused at depth it is also less likely 
to have an affect there; and lung tissue damage has not been observed 
in any mass, multi-species stranding of beaked whales. The frequency at 
which resonance was predicted to occur in the animals' lungs was 50 Hz, 
well below the frequencies used by the MFAS systems associated with the 
Bahamas event. The workshop participants focused on the March 2000 
stranding of beaked whales in the Bahamas as high-quality data were 
available, but the workshop report notes that the results apply to 
other sonar-related stranding events. For the reasons given by the 2002 
workshop participants, we do not anticipate injury due to sonar-induced 
acoustic resonance from the Action Proponents' proposed activity.

Potential Effects of Explosive Sources on Marine Mammals

    Underwater explosive detonations send a shock wave and sound energy 
through the water and can release gaseous by-products, create an 
oscillating bubble, or cause a plume of water to shoot up from the 
water surface. The shock wave and accompanying noise are of most 
concern to marine animals and the potential effects of an explosive 
injury to marine mammals would consist of primary blast injury, which 
refers to injuries resulting from the compression of a body exposed to 
a blast wave. Blast effects are greatest at the gas-liquid interface 
(Landsberg, 2000) and are usually observed as barotrauma of gas-
containing structures (e.g., lung, gastrointestinal tract) and 
structural damage to the auditory system (Goertner, 1982; Greaves et 
al., 1943; Hill, 1978; Office of the Surgeon General, 1991; Richmond et 
al., 1973; Yelverton et al., 1973). Depending on the intensity of the 
shock wave and size, location, and depth of the animal, an animal can 
be injured, killed, suffer non-lethal physical effects, experience 
hearing related effects with or without behavioral responses, or 
exhibit temporary behavioral responses or tolerance from hearing the 
blast sound. Generally, exposures to higher levels of impulse and 
pressure levels would result in greater impacts to an individual 
animal.
    The near instantaneous high magnitude pressure change near an 
explosion can injure an animal where tissue material properties 
significantly differ from the surrounding environment, such as around 
air-filled cavities in the lungs or gastrointestinal tract. Large 
pressure changes at tissue-air interfaces in the lungs and 
gastrointestinal tract may cause tissue rupture, resulting in a range 
of injuries depending on degree of exposure. The lungs are typically 
the first site to show any damage, while the solid organs (e.g., liver, 
spleen, and kidney) are more resistant to blast injury (Clark & Ward, 
1943). Odontocetes can also incur hemorrhaging in the acoustic fats in 
the melon and jaw (Siebert et al., 2022). Recoverable injuries would 
include slight lung injury, such as capillary interstitial bleeding, 
and contusions to the gastrointestinal tract. More severe injuries, 
such as tissue lacerations, major hemorrhage, organ rupture, or air in 
the chest cavity (pneumothorax), would significantly reduce fitness and 
likely cause death in the wild. Rupture of the lung may also introduce 
air into the vascular system, producing air emboli that can cause a 
stroke or heart attack by restricting oxygen delivery to critical 
organs.
    Injuries resulting from a shock wave take place at boundaries 
between tissues of different densities. Different velocities are 
imparted to tissues of different densities, and this can lead to their 
physical disruption. Intestinal walls can bruise or rupture, with 
subsequent hemorrhage and escape of gut contents into the body cavity. 
Less severe gastrointestinal tract injuries include contusions, 
petechiae (small red or purple spots caused by bleeding in the skin), 
and slight hemorrhaging (Yelverton et al., 1973).

[[Page 19934]]

    Relatively little is known about auditory system trauma in marine 
mammals resulting from explosive exposure, although it is assumed that 
auditory structures would be vulnerable to blast injuries because the 
ears are the most sensitive to pressure and, therefore, they are the 
organs most sensitive to injury (Ketten, 2000). Sound-related damage 
associated with sound energy from detonations can be theoretically 
distinct from injury from the shock wave, particularly farther from the 
explosion. If a noise is audible to an animal, it has the potential to 
damage the animal's hearing by causing decreased sensitivity (Ketten, 
1995). Lethal impacts are those that result in immediate death or 
serious debilitation in or near an intense source and are not, 
technically, pure acoustic trauma (Ketten, 1995). Sublethal impacts 
include hearing loss, which is caused by exposures to perceptible 
sounds. Severe damage (from the shock wave) to the ears includes 
tympanic membrane rupture, fracture of the ossicles, damage to the 
cochlea, hemorrhage, and cerebrospinal fluid leakage into the middle 
ear. Moderate injury implies partial hearing loss due to tympanic 
membrane rupture and blood in the middle ear. Permanent hearing loss 
also can occur when the hair cells are damaged by one very loud event, 
as well as by prolonged exposure to a loud noise or chronic exposure to 
noise. The level of impact from blasts depends on both an animal's 
location and, at outer zones, on its sensitivity to the residual noise 
(Ketten, 1995). Auditory trauma was found in 2 humpback whales that 
died after the detonation of a 11,023 lb (5,000 kg) explosive used off 
Newfoundland during demolition of an offshore oil rig platform (Ketten 
et al., 1993), but the proximity of the whales to the detonation was 
unknown. Eardrum rupture was examined in submerged terrestrial mammals 
exposed to underwater explosions (Richmond et al., 1973; Yelverton et 
al., 1973); however, results may not be applicable to the anatomical 
adaptations for underwater hearing in marine mammals.
    In general, models predict that an animal would be less susceptible 
to injury near the water surface because the pressure wave reflected 
from the water surface would interfere with the direct path pressure 
wave, reducing positive pressure exposure (Goertner, 1982; Yelverton & 
Richmond, 1981). This is shown in the records of humans exposed to 
blast while in the water, which show that the gastrointestinal tract 
was more likely to be injured than the lungs, likely due to the 
shallower exposure geometry of the lungs (i.e., closer to the water 
surface) (Lance et al., 2015). Susceptibility would increase with 
depth, until normal lung collapse (due to increasing hydrostatic 
pressure) and increasing ambient pressures again reduce susceptibility 
(Goertner, 1982). The only known occurrence of mortality or injury to a 
marine mammal due to a Navy training event involving explosives 
occurred in March 2011 in nearshore waters off San Diego, California, 
at the Silver Strand Training Complex (see Strandings Associated with 
Explosive Use section below).
    Controlled tests with a variety of lab animals (mice, rats, dogs, 
pigs, sheep, and other species) are the best data sources on actual 
injury to mammals due to underwater exposure to explosions. In the 
early 1970s, the Lovelace Foundation for Medical Education and Research 
conducted a series of tests in an artificial pond at Kirtland Air Force 
Base, New Mexico, to determine the effects of underwater explosions on 
mammals, with the goal of determining safe ranges for human divers. The 
resulting data were summarized in two reports (Richmond et al., 1973; 
Yelverton et al., 1973). Specific physiological observations for each 
test animal are documented in Richmond et al. (1973). Gas-containing 
internal organs, such as lungs and intestines, were the principle 
damage sites in submerged terrestrial mammals; this is consistent with 
earlier studies of mammal exposures to underwater explosions in which 
lungs were consistently the first areas to show damage, with less 
consistent damage observed in the gastrointestinal tract (Clark & Ward, 
1943; Greaves et al., 1943).
    In the Lovelace studies, the first positive acoustic impulse was 
found to be the metric most related to degree of injury, and size of an 
animal's gas-containing cavities was thought to play a role in blast 
injury susceptibility. For these shallow exposures of small terrestrial 
mammals (masses ranging from 3.4 to 50 kg) to underwater detonations, 
Richmond et al. (1973) reported that no blast injuries were observed 
when exposures were less than 6 pounds per square inch per millisecond 
(psi-ms) (40 pascal seconds (Pa-s)), no instances of slight lung 
hemorrhage occurred below 20 psi-ms (140 Pa-s), and instances of no 
lung damage were observed in some exposures at higher levels up to 40 
psi-ms (280 Pa-s). An impulse of 34 psi-ms (230 Pa-s) resulted in about 
50 percent incidence of slight lung hemorrhage. About half of the 
animals had gastrointestinal tract contusions (with slight ulceration, 
i.e., some perforation of the mucosal layer) at exposures of 25-27 psi-
ms (170-190 Pa-s). Lung injuries were found to be slightly more 
prevalent than gastrointestinal tract injuries for the same exposure. 
The anatomical differences between the terrestrial animals used in the 
Lovelace tests and marine mammals are summarized in Fetherston et al. 
(2019). Goertner (1982) examined how lung cavity size would affect 
susceptibility to blast injury by considering both marine mammal size 
and depth in a bubble oscillation model of the lung; however, the 
Goertner (1982) model did not consider how tissues surrounding the 
respiratory air spaces would reflect shock wave energy or constrain 
oscillation (Fetherston et al., 2019).
    Goertner (1982) suggested a peak overpressure gastrointestinal 
tract injury criterion because the size of gas bubbles in the 
gastrointestinal tract are variable, and their oscillation period could 
be short relative to primary blast wave exposure duration. The 
potential for gastrointestinal tract injury, therefore, may not be 
adequately modeled by the single oscillation bubble methodology used to 
estimate lung injury due to impulse. Like impulse, however, high 
instantaneous pressures may damage many parts of the body, but damage 
to the gastrointestinal tract is used as an indicator of any peak 
pressure-induced injury due to its vulnerability.
    Because gas-containing organs are more vulnerable to primary blast 
injury, adaptations for diving that allow for collapse of lung tissues 
with depth may make animals less vulnerable to lung injury with depth. 
Adaptations for diving include a flexible thoracic cavity, distensible 
veins that can fill space as air compresses, elastic lung tissue, and 
resilient tracheas with interlocking cartilaginous rings that provide 
strength and flexibility (Ridgway, 1972). Denk et al. (2020) found 
intra-species differences in the compliance of tracheobronchial 
structures of post-mortem cetaceans and pinnipeds under diving 
hydrostatic pressures, which would affect depth of alveolar collapse. 
Older literature suggested complete lung collapse depths at 
approximately 229.7 ft (70 m) for dolphins (Ridgway & Howard, 1979) and 
65.6 to 164 ft (20 to 50 m) for phocid seals (Falke et al., 1985; 
Kooyman et al., 1972). Follow-on work by Kooyman and Sinnett (1982), in 
which pulmonary shunting was studied in harbor seals and sea lions, 
suggested that complete lung collapse for these species would be about 
557.7 ft (170 m) and about 590.6 (180 m), respectively. Evidence in sea 
lions suggests that

[[Page 19935]]

complete collapse might not occur until depths as great as 738.2 ft 
(225 m); although the depth of collapse and depth of the dive are 
related, sea lions can affect the depth of lung collapse by varying the 
amount of air inhaled on a dive (McDonald and Ponganis, 2012). This is 
an important consideration for all divers who can modulate lung volume 
and gas exchange prior to diving via the degree of inhalation and 
during diving via exhalation (Fahlman et al., 2009); indeed, there are 
noted differences in pre-dive respiratory behavior, with some marine 
mammals exhibiting pre-dive exhalation to reduce the lung volume (e.g., 
phocid seals) (Kooyman et al., 1973).

Further Potential Effects of Behavioral Disturbance on Marine Mammal 
Fitness

    The different ways that marine mammals respond to sound are 
sometimes indicators of the ultimate effect that exposure to a given 
stimulus will have on the well-being (survival, reproduction, etc.) of 
an animal. The long-term consequences of disturbance, hearing loss, 
chronic masking, and acute or chronic physiological stress are 
difficult to predict because of the different factors experienced by 
individual animals, such as context of stressor exposure, underlying 
health conditions, and other environmental or anthropogenic stressors. 
Linking these non-lethal effects on individuals to changes in 
population growth rates requires long-term data, which is lacking for 
many populations. We summarize several studies below, but there are few 
quantitative marine mammal data relating the exposure of marine mammals 
to sound to effects on reproduction or survival, though data exists for 
terrestrial species to which we can draw comparisons for marine 
mammals. Several authors have reported that disturbance stimuli may 
cause animals to abandon nesting and foraging sites (Sutherland and 
Crockford, 1993); may cause animals to increase their activity levels 
and suffer premature deaths or reduced reproductive success when their 
energy expenditures exceed their energy budgets (Daan et al., 1996; 
Feare, 1976; Mullner et al., 2004); or may cause animals to experience 
higher predation rates when they adopt risk-prone foraging or migratory 
strategies (Frid and Dill, 2002). Each of these studies addressed the 
consequences of animals shifting from one behavioral state (e.g., 
resting or foraging) to another behavioral state (e.g., avoidance or 
escape behavior) because of human disturbance or disturbance stimuli.
    Lusseau and Bejder (2007) present data from three long-term studies 
illustrating the connections between disturbance from whale-watching 
boats and population-level effects in cetaceans. In Shark Bay 
Australia, the abundance of bottlenose dolphins was compared within 
adjacent control and tourism sites over three consecutive 4.5-year 
periods of increasing tourism levels. Between the second and third time 
periods, in which tourism doubled, dolphin abundance decreased by 15 
percent in the tourism area and did not change significantly in the 
control area. In Fiordland, New Zealand, two populations (Milford and 
Doubtful Sounds) of bottlenose dolphins with tourism levels that 
differed by a factor of seven were observed and significant increases 
in travelling time and decreases in resting time were documented for 
both. Consistent short-term avoidance strategies were observed in 
response to tour boats until a threshold of disturbance was reached 
(average 68 minutes between interactions), after which the response 
switched to a longer-term habitat displacement strategy. For one 
population, tourism only occurred in a part of the home range. However, 
tourism occurred throughout the home range of the Doubtful Sound 
population and once boat traffic increased beyond the 68-minute 
threshold (resulting in abandonment of their home range/preferred 
habitat), reproductive success drastically decreased (increased 
stillbirths) and abundance decreased significantly (from 67 to 56 
individuals in a short period). Last, in a study of Northern Resident 
killer whales off Vancouver Island, exposure to boat traffic was shown 
to reduce foraging opportunities and increase traveling time. A simple 
bioenergetics model was applied to show that the reduced foraging 
opportunities equated to a decreased energy intake of 18 percent, while 
the increased traveling incurred an increased energy output of 3-4 
percent, which suggests that a management action based on avoiding 
interference with foraging might be particularly effective.
    An important variable to consider is duration of disturbance. 
Severity scales used to assess behavioral responses or marine mammals 
to acute sound exposures are not appropriate to apply to sustained or 
chronic exposures, which requires considering the health of a 
population over time rather than a focus on immediate impacts to 
individuals (Southall et al., 2021). For example, short-term costs 
experienced over the course of a week by an otherwise healthy 
individual may be recouped over time after exposure to the stressor 
ends. These short-term costs would be unlikely to result in long-term 
consequences to that individual or to that individual's population. 
Comparatively, long-term costs accumulated by otherwise healthy 
individuals over an entire season, year, or throughout a life stage 
(e.g., pup, juvenile, adult) would be less easily recouped and more 
likely to result in long-term consequences to that individual or 
population.
    Marine mammals exposed to frequent or intense anthropogenic 
activities may leave the area, habituate to the activity, or tolerate 
the disturbance and remain in the area (Wartzok et al., 2003). Highly 
resident or localized populations may also stay in an area of 
disturbance because the cost of displacement is higher than the cost of 
remaining in the area (Forney et al., 2017). As such, an apparent lack 
of response (e.g., no displacement or avoidance of a sound source) does 
not necessarily indicate there is no cost to the individual or 
population, as some resources or habitats may be of such high value 
that animals may choose to stay, even when experiencing the 
consequences of stress, masking, or hearing loss (Forney et al., 2017).
    Longer term displacement can lead to changes in abundance or 
distribution patterns of the species in the affected region (Bejder et 
al., 2006b; Blackwell et al., 2004; Teilmann et al., 2006). For 
example, gray whales in Baja California, Mexico, abandoned a historical 
breeding lagoon in the mid-1960s due to an increase in dredging and 
commercial shipping operations, and only repopulated the lagoon after 
shipping activities had ceased for several years (Bryant et al., 1984). 
Mysticetes in the northeast tended to adjust to vessel traffic over 
several years, trending towards more neutral behavioral responses to 
passing vessels (Watkins, 1986), indicating that some animals may 
habituate to high levels of human activity. A study on bottlenose 
dolphin responses to vessel approaches found that lesser responses in 
populations of dolphins regularly subjected to high levels of vessel 
traffic could be a sign of habituation, or it could be that the more 
sensitive animals in this population previously abandoned the area of 
higher human activity (Bejder et al., 2006a).
    Population characteristics (e.g., whether a population is open or 
closed to immigration and emigration) can influence sensitivity to 
disturbance as well; closed populations could not withstand a higher 
probability of disturbance compared to open

[[Page 19936]]

populations with no limitation on food (New et al., 2020). Predicting 
population trends or long-term displacement patterns due to 
anthropogenic disturbance is challenging due to limited information and 
survey data for many species over sufficient spatiotemporal scales, as 
well as a full understanding of how other factors, such as 
oceanographic oscillations and climate change, affect marine mammal 
presence (Moore and Barlow, 2013; Barlow, 2016; Moore and Barlow, 
2017).
    Population models are necessary to understand and link short-term 
effects to individuals from disturbance (anthropogenic impacts or 
environmental change) to long-term population consequences. Population 
models require inputs for the population size and changes in vital 
rates of the population (e.g., the mean values for survival age, 
lifetime reproductive success, recruitment of new individuals into the 
population), to predict changes in population dynamics (e.g., 
population growth rate). These efforts often rely on bioenergetic 
models, or energy budget models, which analyze energy intake from food 
and energy costs for life functions, such as maintenance, growth, and 
reproduction, either at the individual or population level (Pirotta, 
2022), and model sensitivity analyses have identified the most 
consequential parameters, including prey characteristics, feeding 
processes, energy expenditure, body size, energy storage, and lactation 
capability (Pirotta, 2022). However, there is a high level of 
uncertainty around many parameters in these models (H[uuml]tt et al., 
2023).
    The U.S. National Research Council (NRC) committee on 
Characterizing Biologically Significant Marine Mammal Behavior 
developed an initial conceptual model to link acoustic disturbance to 
population effects and inform data and research needs (NRC, 2005). This 
Population Consequences of Acoustic Disturbance, or PCAD, conceptual 
model linked the parameters of sound exposure, behavior change, life 
function immediately affected, vital rates, and population effects. In 
its report, the committee found that the relationships between vital 
rates and population effects were relatively well understood, but that 
the relationships between the other components of the model were not 
well-known or easily observed.
    Following the PCAD framework (NRC, 2005), an ONR working group 
developed the Potential Consequences of Disturbance (PCoD), outlining 
an updated conceptual model of the relationships linking disturbance to 
changes in behavior and physiology, health, vital rates, and population 
dynamics. The PCoD model considers all types of disturbance, not solely 
anthropogenic or acoustic, and incorporates physiological changes, such 
as stress or injury, along with behavioral changes as a direct result 
of disturbance (National Academies of Sciences Engineering and 
Medicine, 2017). In this framework, behavioral and physiological 
changes can have direct (acute) effects on vital rates, such as when 
changes in habitat use or increased stress levels raise the probability 
of mother-calf separation or predation; they can have indirect and 
long-term (chronic) effects on vital rates, such as when changes in 
time/energy budgets or increased disease susceptibility affect health, 
which then affects vital rates; or they can have no effect to vital 
rates (New et al., 2014; Pirotta et al., 2018a). In addition to 
outlining this general framework and compiling the relevant literature 
that supports it, the authors chose four example species for which 
extensive long-term monitoring data exist (southern elephant seals, 
NARW, Ziphidae beaked whales, and bottlenose dolphins) and developed 
state-space energetic models that can be used to forecast longer-term, 
population-level impacts from behavioral changes. While these are very 
specific models with very specific data requirements that cannot yet be 
applied broadly to project-specific risk assessments for the majority 
of species, as well as requiring significant resources and time to 
conduct (more than is typically available to support regulatory 
compliance for one project), they are a critical first step towards 
being able to quantify the likelihood of a population level effect. 
Since New et al. (2014), several publications have described models 
developed to examine the long-term effects of environmental or 
anthropogenic disturbance of foraging on various life stages of 
selected species (sperm whale, Farmer et al. (2018); California sea 
lion, McHuron et al. (2018); and blue whale, Pirotta, et al. (2018a)).
    The PCoD model identifies the types of data that would be needed to 
assess population-level impacts. These data are lacking for many marine 
mammal species (Booth et al., 2020). Southall et al. (2021) states that 
future modeling and population simulation studies can help determine 
population-wide long-term consequences and impact analysis. However, 
the method to do so is still developing, as there are gaps in the 
literature, possible sampling biases, and results are rarely ground-
truthed, with a few exceptions (Booth et al., 2022; Schwarz et al., 
2022). Nowacek et al. (2016) reviewed technologies such as passive 
acoustic monitoring, tagging, and the use of unmanned aerial vehicles 
which can improve scientists' abilities to study these model inputs and 
link behavioral changes to individual life functions and ultimately 
population-level effects. Relevant data needed for improving analyses 
of population-level consequences resulting from disturbances will 
continue to be collected during the 7-year period of the LOAs through 
projects funded by the Navy's Marine Species Monitoring Program. 
Multiple case studies across marine mammal taxonomic groups have been 
conducted following the PCoD framework. From these studies, Keen et al. 
(2021) identified themes and contextual factors relevant to assessing 
impacts to populations due to disturbance, which have been considered 
in the context of the impacts of the Action Proponents' activities.
    A population's movement ecology determines the potential for 
spatiotemporal overlap with a disturbance. Resident populations or 
populations that rely on spatially limited habitats for critical life 
functions (i.e., foraging, breeding) would be at greater risk of 
repeated or chronic exposure to disturbances than populations that are 
wide-ranging relative to the footprint of a disturbance (Keen et al., 
2021). Even for the same species, differences in habitat use between 
populations can result in different potential for repeated exposure to 
individuals for a similar stressor (Costa et al., 2016a). The location 
and radius of disturbance can impact how many animals are exposed and 
for how long (Costa et al., 2016b). While some models have shown the 
advantages of populations with larger ranges, namely the decreased 
chance of being exposed (Costa et al., 2016b), it's important to 
consider that for some species, the energetic cost of a longer 
migration could make a population more sensitive to energy lost through 
disturbance (Villegas-Amtmann et al., 2017). In addition to ranging 
patterns, a species' activity budgets and lunging rates can cause 
variability in their predicted cost of disturbance as well (Pirotta et 
al., 2021).
    Bioenergetics frameworks that examine the impact of foraging 
disruption on body reserves of individual whales found that rates of 
daily foraging disruption can predict the number of days to terminal 
starvation for various life stages (Farmer et al.,

[[Page 19937]]

2018b). Similarly, when a population is displaced by a stressor, and 
only has access to areas of poor habitat quality (i.e., low prey 
abundance) for relocation, bioenergetic models may be more likely to 
predict starvation, longer recovery times, or extinction (Hin et al., 
2023). There is some debate over the use of blubber thickness as a 
metric of cetacean energy stores and health, as marine mammals may not 
use their fat stores in a similar manner to terrestrial mammals (Derous 
et al., 2020).
    Resource limitation can impact marine mammal population growth rate 
regardless of additional anthropogenic disturbance. Stochastic Dynamic 
Programming models have been used to explore the impact declining prey 
species has on focal marine mammal predators (McHuron et al., 2023a; 
McHuron et al., 2023b). A Stochastic Dynamic Programming model 
determined that a decrease in walleye pollock (Gadus chalcogrammus) 
availability increased the time and distance northern fur seal mothers 
had to travel offshore, which negatively impacted pup growth rate and 
wean mass, despite attempts to compensate with longer recovery time on 
land (McHuron et al., 2023b). Prey is an important factor in long-term 
consequence models for many species of marine mammals. In disturbance 
models that predict habitat displacement or otherwise reduced foraging 
opportunities, populations are being deprived of energy dense prey or 
``high quality'' areas which can lead to long-term impacts on fecundity 
and survival (Czapanskiy et al., 2021; Hin et al., 2019; McHuron et 
al., 2023a; New et al., 2013b). Prey density limits the energy 
available for growth, reproduction, and survival. Some disturbance 
models indicate that the immediate decrease in a portion of the 
population (e.g., young lactating mothers) is not necessarily 
detrimental to a population, since as a result, prey availability 
increases and the population's overall improved body condition reduces 
the age at first calf (Hin et al., 2021). The timing of a disturbance 
with seasonally available resources is also important; if a disturbance 
occurs during periods of low resource availability, the population-
level consequences are greater and occur faster than if the disturbance 
occurs during periods when resource levels are high (Hin et al., 2019). 
Further, when resources are not evenly distributed, populations with 
cautious strategies and knowledge of resource variation have an 
advantage (Pirotta et al., 2020).
    Even when modeled alongside several anthropogenic sources of 
disturbance (e.g., vessel strike, vessel noise, chemical contaminants, 
sonar), several species of marine mammals are most influenced by lack 
of prey (Czapanskiy et al., 2021; Murray et al., 2021). Some species 
like killer whales are especially sensitive to prey abundance due to 
their limited diet (Murray et al., 2021). The short-term energetic cost 
of eleven species of cetaceans and mysticetes exposed to mid-frequency 
active sonar was influenced more by lost foraging opportunities than 
increased locomotor effort during avoidance (Czapanskiy et al., 2021). 
Additionally, the model found that mysticetes incurred more energetic 
cost than odontocetes, even during mild behavioral responses to sonar. 
These results may be useful in the development of future Population 
Consequences of Multiple Stressors and PCoD models since they should 
seek to qualify cetacean health in a more ecologically relevant manner.
    PCoD models have been used to assess the impacts of multiple and 
recurring stressors. A marine mammal population that is already subject 
to chronic stressors like climate change will likely be more vulnerable 
to acute disturbances. Models that have looked at populations of 
cetaceans who are exposed to multiple stressors over several years have 
found that even one major chronic stressor (e.g., climate change, 
epizootic disease, oil spill) has severe impacts on population size. A 
layer of one or more stressor (e.g., seismic surveys) in addition to a 
chronic stressor (like an oil spill) can yield devastating impacts on a 
population. These results may vary based on species and location, as 
one population may be more impacted by chronic shipping noise, while 
another population may not. However, just because a population doesn't 
appear to be impacted by one chronic stressor (e.g., shipping noise), 
does not mean they aren't affected by others, such as climate change or 
disease (Reed et al., 2020). Recurring or chronic stressors can impact 
population abundance even when instances of disturbance are short and 
have minimal behavioral impact on an individual (Farmer et al., 2018a; 
McHuron et al., 2018b; Pirotta et al., 2019). Some changes to response 
variables like pup recruitment (survival to age one) aren't noticeable 
for several years, as the impacts on pup survival does not affect the 
population until those pups are mature but impacts to young animals 
will ultimately lead to population-wide declines. The severity of the 
repeated disturbance can also impact a population's long-term 
reproductive success. Scenarios with severe repeated disturbance (e.g., 
95 percent probability of exposure, with 95 percent reduction in 
feeding efficiency) can severely reduce fecundity and calf survival, 
while a weaker disturbance (25 percent probability of exposure, with 25 
percent reduction in feeding efficiency) had no population-wide effect 
on vital rates (Pirotta et al., 2019).
    Farmer et al. (2018a) modeled how an oil spill led to chronic 
declines in a sperm whale population over 10 years, and if models 
included even one more stressor (i.e., behavioral responses to air 
guns), the population declined even further. However, the amount of 
additional population decline due to acoustic disturbance depended on 
the way the dose-response of the noise levels were modeled. A single 
step-function led to higher impacts than a function with multiple steps 
and frequency weighting. In addition, the amount of impact from both 
disturbances was mediated when the metric in the model that described 
animal resilience was changed to increase resilience to disturbance 
(e.g., able to make up reserves through increased foraging).
    Not all stressors have the same impact for all species and all 
locations. Another model analyzed the effect of a number of chronic 
disturbances on two bottlenose dolphin populations in Australia over 5 
years (Reed et al., 2020). Results indicated that disturbance from 
fisheries interactions and shipping noise had little overall impact on 
population abundances in either location, even in the most extreme 
impact scenarios modeled. At least in this area, epizootic and climate 
change scenarios had the largest impact on population size and 
fecundity.
    Recurring stressors can impact population abundance even when 
individual instances of disturbance are short and have minimal 
behavioral impact on an individual. A model on California sea lions 
introduced a generalized disturbance at different times throughout the 
breeding cycle, with their behavior response being an increase in the 
duration of a foraging trip by the female (McHuron et al., 2018b). Very 
short duration disturbances or responses led to little change, 
particularly if the disturbance was a single event, and changes in the 
timing of the event in the year had little effect. However, with even 
relatively short disturbances or mild responses, when a disturbance was 
modeled as recurring there were resulting reductions in population size 
and pup recruitment (survival to age one). Often,

[[Page 19938]]

the effects weren't noticeable for several years, as the impacts on pup 
survival did not affect the population until those pups were mature.

Stranding and Mortality

    The definition for a stranding under title IV of the MMPA is that 
(A) a marine mammal is dead and is (i) on a beach or shore of the 
United States; or (ii) in waters under the jurisdiction of the United 
States (including any navigable waters); or (B) a marine mammal is 
alive and is (i) on a beach or shore of the United States and is unable 
to return to the water; (ii) on a beach or shore of the United States 
and, although able to return to the water, is in need of apparent 
medical attention; or (iii) in the waters under the jurisdiction of the 
United States (including any navigable waters), but is unable to return 
to its natural habitat under its own power or without assistance (see 
MMPA section 410(3)). This definition is useful for considering 
stranding events even when they occur beyond lands and waters under the 
jurisdiction of the United States.
    Marine mammal strandings have been linked to a variety of causes, 
such as illness from exposure to infectious agents, biotoxins, or 
parasites; starvation; unusual oceanographic or weather events; or 
anthropogenic causes including fishery interaction, vessel strike, 
entrainment, entrapment, sound exposure, or combinations of these 
stressors sustained concurrently or in series. Historically, the cause 
or causes of most strandings have remained unknown (Geraci et al., 
1976; Eaton, 1979, Odell et al., 1980; Best, 1982), but the development 
of trained, professional stranding response networks and improved 
analyses have led to a greater understanding of marine mammal stranding 
causes (Simeone and Moore 2017).
    Numerous studies suggest that the physiology, behavior, habitat, 
social relationships, age, or condition of cetaceans may cause them to 
strand or might predispose them to strand when exposed to another 
phenomenon. These suggestions are consistent with the conclusions of 
numerous other studies that have demonstrated that combinations of 
dissimilar stressors commonly combine to kill an animal or dramatically 
reduce its fitness, even though one exposure without the other does not 
produce the same result (Bernaldo de Quiros et al., 2019; Chroussos, 
2000; Creel, 2005; DeVries et al., 2003; Fair and Becker, 2000; Foley 
et al., 2001; Moberg, 2000; Relyea, 2005a; 2005b, Romero, 2004; Sih et 
al., 2004).
    Historically, stranding reporting and response efforts have been 
inconsistent, although significant improvements have occurred over the 
last 25 years. Reporting forms for basic (``Level A'') information, 
rehabilitation disposition, and human interaction have been 
standardized nationally (available at https://www.fisheries.noaa.gov/national/marine-mammal-protection/level-data-collection-marine-mammal-stranding-events). However, data collected beyond basic information 
varies by region (and may vary from case to case), and are not 
standardized across the United States. Logistical conditions such as 
weather, time, location, and decomposition state may also affect the 
ability of the stranding network to thoroughly examine a specimen 
(Carretta et al., 2023; Moore et al., 2013). While the investigation of 
stranded animals provides insight into the types of threats marine 
mammal populations face, full investigations are only possible and 
conducted on a small fraction of the total number of strandings that 
occur, limiting our understanding of the causes of strandings (Carretta 
et al., 2016a). Additionally, and due to the variability in effort and 
data collected, the ability to interpret long-term trends in stranded 
marine mammals is complicated.
    In the United States from 2006-2022, there were 27,781 cetacean 
strandings and 79,572 pinniped strandings (107,353 total) (P. Onens, 
NMFS, pers comm., 2024). Several mass strandings (strandings that 
involve two or more individuals of the same species, excluding a single 
mother-calf pair) that have occurred over the past two decades have 
been associated with anthropogenic activities that introduced sound 
into the marine environment such as naval operations and seismic 
surveys. An in-depth discussion of strandings can be found in appendix 
D of the 2024 AFTT Draft Supplemental EIS/OEIS and in the Navy's 
Technical Report on Marine Mammal Strandings Associated with U.S. Navy 
Sonar Activities (U.S. Navy Marine Mammal Program & Space and Naval 
Warfare Systems Command Center Pacific, 2017).
    Worldwide, there have been several efforts to identify 
relationships between cetacean mass stranding events and military 
active sonar (Cox et al., 2006, Hildebrand, 2004; Taylor et al., 2004). 
For example, based on a review of mass stranding events around the 
world consisting of two or more individuals of goose-beaked whales, 
records from the International Whaling Commission (IWC) (2005) show 
that a quarter (9 of 41) were associated with concurrent naval patrol, 
explosion, maneuvers, or MFAS. D'Amico et al. (2009) reviewed beaked 
whale stranding data compiled primarily from the published literature, 
which provides an incomplete record of stranding events, as many are 
not written up for publication, along with unpublished information from 
some regions of the world.
    Most of the stranding events reviewed by the IWC involved beaked 
whales. A mass stranding of goose-beaked whales in the eastern 
Mediterranean Sea occurred in 1996 (Frantzis, 1998), and mass stranding 
events involving Gervais' beaked whales, Blainville's beaked whales, 
and goose-beaked whales occurred off the coast of the Canary Islands in 
the late 1980s (Simmonds and Lopez-Jurado, 1991). The stranding events 
that occurred in the Canary Islands and Kyparissiakos Gulf in the late 
1990s and the Bahamas in 2000 have been the most intensively-studied 
mass stranding events and have been associated with naval maneuvers 
involving the use of tactical sonar. Other cetacean species with naval 
sonar implicated in stranding events include harbor porpoise (Norman et 
al., 2004, Wright et al., 2013) and common dolphin (Jepson and Deaville 
2009).
Strandings Associated With Active Sonar
    Over the past 21 years, there have been 5 stranding events 
coincident with military MFAS use in which exposure to sonar is 
believed to have been a contributing factor: Greece (1996); the Bahamas 
(2000); Madeira (2000); Canary Islands (2002); and Spain (2006) (Cox et 
al., 2006; Fernandez, 2006; U.S. Navy Marine Mammal Program & Space and 
Naval Warfare Systems Command Center Pacific, 2017). These five mass 
strandings have resulted in about 40 known cetacean deaths consisting 
mostly of beaked whales and with close linkages to MFAS activity. In 
these circumstances, exposure to non-impulsive acoustic energy was 
considered a potential indirect cause of death of the marine mammals 
(Cox et al., 2006). Only one of these stranding events, the Bahamas 
(2000), was associated with exercises conducted by the U.S. Navy. 
Additionally, in 2004, during the Rim of the Pacific (RIMPAC) 
exercises, between 150 and 200 usually pelagic melon-headed whales 
occupied the shallow waters of Hanalei Bay, Kaua'i, Hawaii for over 28 
hours. NMFS determined that MFAS was a plausible, if not likely, 
contributing factor in what may have been a confluence of events that 
led to the Hanalei Bay stranding. A number of other stranding events 
coincident with the operation of MFAS,

[[Page 19939]]

including the death of beaked whales or other species (minke whales, 
dwarf sperm whales, pilot whales), have been reported; however, the 
majority have not been investigated to the degree necessary to 
determine the cause of the stranding. Most recently, the Independent 
Scientific Review Panel investigating potential contributing factors to 
a 2008 mass stranding of melon-headed whales in Antsohihy, Madagascar 
released its final report suggesting that the stranding was likely 
initially triggered by an industry seismic survey (Southall et al., 
2013). This report suggests that the operation of a commercial high-
powered 12 kHz multibeam echosounder during an industry seismic survey 
was a plausible and likely initial trigger that caused a large group of 
melon-headed whales to leave their typical habitat and then ultimately 
strand as a result of secondary factors such as malnourishment and 
dehydration. The report indicates that the risk of this particular 
convergence of factors and ultimate outcome is likely very low, but 
recommends that the potential be considered in environmental planning. 
Because of the association between tactical MFAS use and a small number 
of marine mammal strandings, the Navy and NMFS have been considering 
and addressing the potential for strandings in association with Navy 
activities for years. In addition to the proposed mitigation measures 
intended to more broadly minimize impacts to marine mammals, the Navy 
will abide by the Notification and Reporting Plan, which sets out 
notification, reporting, and other requirements when dead, injured, or 
stranded marine mammals are detected in certain circumstances.
Greece (1996)--
    Twelve goose-beaked whales stranded atypically (in both time and 
space) along a 23.7 mi (38.2 km) strand of the Kyparissiakos Gulf coast 
on May 12 and 13, 1996 (Frantzis, 1998). From May 11 through May 15, 
the North Atlantic Treaty Organization (NATO) research vessel Alliance 
was conducting sonar tests with signals of 600 Hz and 3 kHz and source 
levels of 228 and 226 dB re 1 [mu]Pa, respectively (D'Amico and 
Verboom, 1998; D'Spain et al., 2006). The timing and location of the 
testing encompassed the time and location of the strandings (Frantzis, 
1998).
    Necropsies of eight of the animals were performed but were limited 
to basic external examination and sampling of stomach contents, blood, 
and skin. No ears or organs were collected, and no histological samples 
were preserved. No significant apparent abnormalities or wounds were 
found, however examination of photos of the animals, taken soon after 
their death, revealed that the eyes of at least four of the individuals 
were bleeding (Frantzis, 2004). Stomach contents contained the flesh of 
cephalopods, indicating that feeding had recently taken place 
(Frantzis, 1998).
    All available information regarding the conditions associated with 
this stranding event was compiled, and many potential causes were 
examined including major pollution events, prominent tectonic activity, 
unusual physical or meteorological events, magnetic anomalies, 
epizootics, and conventional military activities (International Council 
for the Exploration of the Sea, 2005). However, none of these potential 
causes coincided in time or space with the mass stranding, or could 
explain its characteristics (International Council for the Exploration 
of the Sea, 2005). The robust condition of the animals, plus the recent 
stomach contents, is inconsistent with pathogenic causes. In addition, 
environmental causes can be ruled out as there were no unusual 
environmental circumstances or events before or during this time period 
and within the general proximity (Frantzis, 2004).
    Because of the rarity of this mass stranding of goose-beaked whales 
in the Kyparissiakos Gulf (first one in historical records), the 
probability for the two events (the military exercises and the 
strandings) to coincide in time and location, while being independent 
of each other, was thought to be extremely low (Frantzis, 1998). 
However, because full necropsies had not been conducted, and no 
abnormalities were noted, the cause of the strandings could not be 
precisely determined (Cox et al., 2006). A Bioacoustics Panel convened 
by NATO concluded that the evidence available did not allow them to 
accept or reject sonar exposures as a causal agent in these stranding 
events. The analysis of this stranding event provided support for, but 
no clear evidence for, the cause-and-effect relationship of tactical 
sonar training activities and beaked whale strandings (Cox et al., 
2006).
Bahamas (2000)--
    NMFS and the Navy prepared a joint report addressing the multi-
species stranding in the Bahamas in 2000, which took place within 24 
hours of U.S. Navy ships using MFAS as they passed through the 
Northeast and Northwest Providence Channels on March 15-16, 2000. The 
ships, which operated both AN/SQS-53C and AN/SQS-56, moved through the 
channel while emitting sonar pings approximately every 24 seconds. Of 
the 17 cetaceans that stranded over a 36-hour period (goose-beaked 
whales, Blainville's beaked whales, minke whales, and a spotted 
dolphin), 7 animals died on the beach (5 goose-beaked whales, 1 
Blainville's beaked whale, and 1 spotted dolphin), while the other 10 
were returned to the water alive (though their ultimate fate is 
unknown). As discussed in the Bahamas report (DOC/DON, 2001), there is 
no likely association between the minke whale and spotted dolphin 
strandings and the operation of MFAS.
    Necropsies were performed on five of the stranded beaked whales. 
All five necropsied beaked whales were in good body condition, showing 
no signs of infection, disease, vessel strike, blunt trauma, or fishery 
related injuries, and three still had food remains in their stomachs. 
Auditory structural damage was discovered in four of the whales, 
specifically bloody effusions or hemorrhaging around the ears. 
Bilateral intracochlear and unilateral temporal region subarachnoid 
hemorrhage, with blood clots in the lateral ventricles, were found in 
two of the whales. Three of the whales had small hemorrhages in their 
acoustic fats (located along the jaw and in the melon).
    A comprehensive investigation was conducted and all possible causes 
of the stranding event were considered, whether they seemed likely at 
the outset or not. Based on the way in which the strandings coincided 
with ongoing naval activity involving tactical MFAS use, in terms of 
both time and geography, the nature of the physiological effects 
experienced by the dead animals, and the absence of any other acoustic 
sources, the investigation team concluded that MFAS aboard U.S. Navy 
ships that were in use during the active sonar exercise in question 
were the most plausible source of this acoustic or impulse trauma to 
beaked whales. This sound source was active in a complex environment 
that included the presence of a surface duct, unusual and steep 
bathymetry, a constricted channel with limited egress, intensive use of 
multiple, active sonar units over an extended period of time, and the 
presence of beaked whales that appear to be sensitive to the 
frequencies produced by these active sonars. The investigation team 
concluded that the cause of this stranding event was the confluence of 
the Navy MFAS and these contributory factors working together, and 
further recommended that the Navy avoid operating MFAS in situations 
where these five factors would be likely to occur. This report does not 
conclude

[[Page 19940]]

that all five of these factors must be present for a stranding to 
occur, nor that beaked whales are the only species that could 
potentially be affected by the confluence of the other factors. Based 
on this, NMFS believes that the operation of MFAS in situations where 
surface ducts exist, or in marine environments defined by steep 
bathymetry and/or constricted channels may increase the likelihood of 
producing a sound field with the potential to cause cetaceans 
(especially beaked whales) to strand, and therefore, suggests the need 
for increased vigilance while operating MFAS in these areas, especially 
when beaked whales (or potentially other deep divers) are likely 
present.
Madeira, Portugal (2000)--
    From May 10-14, 2000, three goose-beaked whales were found 
atypically stranded on two islands in the Madeira archipelago, Portugal 
(Cox et al., 2006). A fourth animal was reported floating in the 
Madeiran waters by fisherman but did not come ashore (Woods Hole 
Oceanographic Institution, 2005). Joint NATO amphibious training 
peacekeeping exercises involving participants from 17 countries and 80 
warships, took place in Portugal during May 2-15, 2000.
    The bodies of the three stranded whales were examined postmortem 
(Woods Hole Oceanographic Institution, 2005), though only one of the 
stranded whales was fresh enough (24 hours after stranding) to be 
necropsied (Cox et al., 2006). Results from the necropsy revealed 
evidence of hemorrhage and congestion in the right lung and both 
kidneys (Cox et al., 2006). There was also evidence of intercochlear 
and intracranial hemorrhage similar to that which was observed in the 
whales that stranded in the Bahamas event (Cox et al., 2006). There 
were no signs of blunt trauma, and no major fractures, and the cranial 
sinuses and airways were found to be clear with little or no fluid 
deposition, which may indicate good preservation of tissues (Woods Hole 
Oceanographic Institution, 2005).
    Several observations on the Madeira stranded beaked whales, such as 
the pattern of injury to the auditory system, are the same as those 
observed in the Bahamas strandings. Blood in and around the eyes, 
kidney lesions, pleural hemorrhages, and congestion in the lungs are 
particularly consistent with the pathologies from the whales stranded 
in the Bahamas, and are consistent with stress and pressure related 
trauma. The similarities in pathology and stranding patterns between 
these two events suggest that a similar pressure event may have 
precipitated or contributed to the strandings at both sites (Woods Hole 
Oceanographic Institution, 2005).
    Even though no definitive causal link can be made between the 
stranding event and naval exercises, certain conditions may have 
existed in the exercise area that, in their aggregate, may have 
contributed to the marine mammal strandings (Freitas, 2004): exercises 
were conducted in areas of at least 547 fathoms (1,000 m) depth near a 
shoreline where there is a rapid change in bathymetry on the order of 
547 to 3,281 fathoms (1,000 to 6,000 m) occurring across a relatively 
short horizontal distance (Freitas, 2004); multiple ships were 
operating around Madeira, though it is not known if MFAS was used, and 
the specifics of the sound sources used are unknown (Cox et al., 2006; 
Freitas, 2004); and exercises took place in an area surrounded by 
landmasses separated by less than 35 nmi (65 km) and at least 10 nmi 
(19 km) in length, or in an embayment. Exercises involving multiple 
ships employing MFAS near land may produce sound directed towards a 
channel or embayment that may cut off the lines of egress for marine 
mammals (Freitas, 2004).
Canary Islands, Spain (2002)--
    The southeastern area within the Canary Islands is well known for 
aggregations of beaked whales due to its ocean depths of greater than 
547 fathoms (1,000 m) within a few hundred meters of the coastline 
(Fernandez et al., 2005). On September 24, 2002, 14 beaked whales were 
found stranded on Fuerteventura and Lanzarote Islands in the Canary 
Islands (International Council for Exploration of the Sea, 2005a). 
Seven whales died, while the remaining seven live whales were returned 
to deeper waters (Fernandez et al., 2005). Four beaked whales were 
found stranded dead over the next three days either on the coast or 
floating offshore. These strandings occurred within close proximity of 
an international naval exercise that utilized MFAS and involved 
numerous surface warships and several submarines. Strandings began 
about four hours after the onset of MFAS activity (International 
Council for Exploration of the Sea, 2005a; Fernandez et al., 2005).
    Eight goose-beaked whales, one Blainville's beaked whale, and one 
Gervais' beaked whale were necropsied, 6 of them within 12 hours of 
stranding (Fernandez et al., 2005). No pathogenic bacteria were 
isolated from the carcasses (Jepson et al., 2003). The animals 
displayed severe vascular congestion and hemorrhage especially around 
the tissues in the jaw, ears, brain, and kidneys, displaying marked 
disseminated microvascular hemorrhages associated with widespread fat 
emboli (Jepson et al., 2003; International Council for Exploration of 
the Sea, 2005a). Several organs contained intravascular bubbles, 
although definitive evidence of gas embolism in vivo is difficult to 
determine after death (Jepson et al., 2003). The livers of the 
necropsied animals were the most consistently affected organ, which 
contained macroscopic gas-filled cavities and had variable degrees of 
fibrotic encapsulation. In some animals, cavitary lesions had 
extensively replaced the normal tissue (Jepson et al., 2003). Stomachs 
contained a large amount of fresh and undigested contents, suggesting a 
rapid onset of disease and death (Fernandez et al., 2005). Head and 
neck lymph nodes were enlarged and congested, and parasites were found 
in the kidneys of all animals (Fernandez et al., 2005).
    The association of NATO MFAS use close in space and time to the 
beaked whale strandings, and the similarity between this stranding 
event and previous beaked whale mass strandings coincident with sonar 
use, suggests that a similar scenario and causative mechanism of 
stranding may be shared between the events. Beaked whales stranded in 
this event demonstrated brain and auditory system injuries, 
hemorrhages, and congestion in multiple organs, similar to the 
pathological findings of the Bahamas and Madeira stranding events. In 
addition, the necropsy results of the Canary Islands stranding event 
lead to the hypothesis that the presence of disseminated and widespread 
gas bubbles and fat emboli were indicative of nitrogen bubble 
formation, similar to what might be expected in decompression sickness 
(Jepson et al., 2003; Fern[aacute]ndez et al., 2005).
Hanalei Bay (2004)--
    On July 3 and 4, 2004, approximately 150 to 200 melon-headed whales 
occupied the shallow waters of Hanalei Bay, Kaua'i, Hawaii for over 28 
hours. Attendees of a canoe blessing observed the animals entering the 
Bay in a single wave formation at 7 a.m. on July 3, 2004. The animals 
were observed moving back into the shore from the mouth of the Bay at 9 
a.m. The usually pelagic animals milled in the shallow bay and were 
returned to deeper water with human assistance beginning at 9:30 a.m. 
on July 4, 2004, and were out of sight by 10:30 a.m.

[[Page 19941]]

    Only one animal, a calf, was known to have died following this 
event. The animal was noted alive and alone in the Bay on the afternoon 
of July 4, 2004, and was found dead in the Bay the morning of July 5, 
2004. A full necropsy, magnetic resonance imaging, and computerized 
tomography examination were performed on the calf to determine the 
manner and cause of death. The combination of imaging, necropsy and 
histological analyses found no evidence of infectious, internal 
traumatic, congenital, or toxic factors. Cause of death could not be 
definitively determined, but it is likely that maternal separation, 
poor nutritional condition, and dehydration contributed to the final 
demise of the animal. Although it is not known when the calf was 
separated from its mother, the animals' movement into the Bay and 
subsequent milling and re-grouping may have contributed to the 
separation or lack of nursing, especially if the maternal bond was weak 
or this was an inexperienced mother with her first calf.
    Environmental factors, abiotic and biotic, were analyzed for any 
anomalous occurrences that would have contributed to the animals 
entering and remaining in Hanalei Bay. The Bay's bathymetry is similar 
to many other sites within the Hawaiian Island chain and dissimilar to 
sites that have been associated with mass strandings in other parts of 
the United States. The weather conditions appeared to be normal for 
that time of year with no fronts or other significant features noted. 
There was no evidence of unusual distribution, occurrence of predator 
or prey species, or unusual harmful algal blooms, although Mobley et 
al. (2007) suggested that the full moon cycle that occurred at that 
time may have influenced a run of squid into the Bay. Weather patterns 
and bathymetry that have been associated with mass strandings elsewhere 
were not found to occur in this instance.
    The Hanalei event was spatially and temporally correlated with 
RIMPAC. Official sonar training and tracking exercises in the Pacific 
Missile Range Facility (PMRF) warning area did not commence until 
approximately 8 a.m. on July 3 and were thus ruled out as a possible 
trigger for the initial movement into the bay. However, six naval 
surface vessels transiting to the operational area on July 2 
intermittently transmitted active sonar (for approximately 9 hours 
total from 1:15 p.m. to 12:30 a.m.) as they approached from the south. 
The potential for these transmissions to have triggered the whales' 
movement into Hanalei Bay was investigated. Analyses with the 
information available indicated that animals to the south and east of 
Kaua'i could have detected active sonar transmissions on July 2, and 
reached Hanalei Bay on or before 7 a.m. on July 3. However, data 
limitations regarding the position of the whales prior to their arrival 
in the Bay, the magnitude of sonar exposure, behavioral responses of 
melon-headed whales to acoustic stimuli, and other possible relevant 
factors preclude a conclusive finding regarding the role of sonar in 
triggering this event. Propagation modeling suggests that transmissions 
from sonar use during the July 3 exercise in the PMRF warning area may 
have been detectable at the mouth of the bay. If the animals responded 
negatively to these signals, it may have contributed to their continued 
presence in the bay. The U.S. Navy ceased all active sonar 
transmissions during exercises in this range on the afternoon of July 
3. Subsequent to the cessation of sonar use, the animals were herded 
out of the bay.
    While causation of this stranding event may never be unequivocally 
determined, NMFS considers the active sonar transmissions of July 2-3, 
2004, a plausible, if not likely, contributing factor in what may have 
been a confluence of events. This conclusion is based on the following: 
(1) the evidently anomalous nature of the stranding; (2) its close 
spatiotemporal correlation with wide-scale, sustained use of sonar 
systems previously associated with stranding of deep-diving marine 
mammals; (3) the directed movement of two groups of transmitting 
vessels toward the southeast and southwest coast of Kaua'i; (4) the 
results of acoustic propagation modeling and an analysis of possible 
animal transit times to the bay; and (5) the absence of any other 
compelling causative explanation. The initiation and persistence of 
this event may have resulted from an interaction of biological and 
physical factors. The biological factors may have included the presence 
of an apparently uncommon, deep-diving cetacean species (and possibly 
an offshore, non-resident group), social interactions among the animals 
before or after they entered the bay, and/or unknown predator or prey 
conditions. The physical factors may have included the presence of 
nearby deep water, multiple vessels transiting in a directed manner 
while transmitting active sonar over a sustained period, the presence 
of surface sound ducting conditions, and/or intermittent and random 
human interactions while the animals were in the bay.
    A separate event involving melon-headed whales and rough-toothed 
dolphins took place over the same period of time in the Northern 
Mariana Islands (Jefferson et al., 2006), which is several thousand 
miles from Hawaii. Some 500 to 700 melon-headed whales came into 
Sasanhaya Bay on July 4, 2004, near the island of Rota and then left of 
their own accord after 5.5 hours; no known active sonar transmissions 
occurred in the vicinity of that event. The Rota incident led to 
scientific debate regarding what, if any, relationship the event had to 
the simultaneous events in Hawaii and whether they might be related by 
some common factor (e.g., there was a full moon on July 2, 2004, as 
well as during other melon-headed whale strandings and nearshore 
aggregations (Brownell et al., 2009; Lignon et al., 2007; Mobley et 
al., 2007). Brownell et al. (2009) compared the two incidents, along 
with one other stranding incident at Nuka Hiva in French Polynesia and 
normal resting behaviors observed at Palmyra Island, in regard to 
physical features in the areas, melon-headed whale behavior, and lunar 
cycles. Brownell et al., (2009) concluded that the rapid entry of the 
whales into Hanalei Bay, their movement into very shallow water far 
from the 328-ft (100-m) contour, their milling behavior (typical pre-
stranding behavior), and their reluctance to leave the bay constituted 
an unusual event that was not similar to the events that occurred at 
Rota, which appear to be similar to observations of melon-headed whales 
resting normally at Palmyra Island. Additionally, there was no 
correlation between lunar cycle and the types of behaviors observed in 
the Brownell et al. (2009) examples.
Spain (2006)--
    The Spanish Cetacean Society reported an atypical mass stranding of 
four beaked whales that occurred January 26, 2006, on the southeast 
coast of Spain, near Moj[aacute]car (Gulf of Vera) in the Western 
Mediterranean Sea. According to the report, two of the whales were 
discovered the evening of January 26 and were found to be still alive. 
Two other whales were discovered during the day on January 27 but had 
already died. The first three animals were located near the town of 
Moj[aacute]car and the fourth animal was found dead, a few kilometers 
north of the first three animals. From January 25-26, 2006, Standing 
NATO Response Force Maritime Group Two (five of seven ships including 
one U.S. ship under NATO Operational Control) had conducted active 
sonar training against a Spanish submarine within 50 nmi (93 km) of the 
stranding site.

[[Page 19942]]

    Veterinary pathologists necropsied the two male and two female 
goose-beaked whales. According to the pathologists, the most likely 
primary cause of this type of beaked whale mass stranding event was 
anthropogenic acoustic activities, most probably anti-submarine MFAS 
used during the military naval exercises. However, no positive acoustic 
link was established as a direct cause of the stranding. Even though no 
causal link can be made between the stranding event and naval 
exercises, certain conditions may have existed in the exercise area 
that, in their aggregate, may have contributed to the marine mammal 
strandings (Freitas, 2004). Exercises were conducted in areas of at 
least 547 fathoms (1,000 m) depth near a shoreline where there is a 
rapid change in bathymetry on the order of 547 to 3,281 fathoms (1,000 
to 6,000 m) occurring across a relatively short horizontal distance 
(Freitas, 2004). Multiple ships (in this instance, five) were operating 
MFAS in the same area over extended periods of time (in this case, 20 
hours) in close proximity; and exercises took place in an area 
surrounded by landmasses, or in an embayment. Exercises involving 
multiple ships employing MFAS near land may have produced sound 
directed towards a channel or embayment that may have cut off the lines 
of egress for the affected marine mammals (Freitas, 2004).
Honaunau Bay (2022)--
    On March 25, 2022, a beaked whale (species unknown) stranded in 
Honaunau Bay, Hawaii. The animal was observed swimming into shore and 
over rocks. Bystanders intervened to turn the animal off of the rocks, 
and it swam back out of the Bay on its own. Locals reported hearing a 
siren or alarm type of sound underwater on the same day, and a Navy 
vessel was observed from shore on the following day. The Navy confirmed 
it used CAS within 27 nmi (50 km) and 48 hours of the time of 
stranding, though the stranding has not been definitively linked to the 
Navy's CAS use.
Behaviorally Mediated Responses to MFAS That May Lead To Stranding
    Although the confluence of Navy MFAS with the other contributory 
factors noted in the 2001 NMFS/Navy joint report was identified as the 
cause of the 2000 Bahamas stranding event, the specific mechanisms that 
led to that stranding (or the others) are not well understood, and 
there is uncertainty regarding the ordering of effects that led to the 
stranding. It is unclear whether beaked whales were directly injured by 
sound (e.g., acoustically mediated bubble growth, as addressed above) 
prior to stranding or whether a behavioral response to sound occurred 
that ultimately caused the beaked whales to be injured and strand.
    Although causal relationships between beaked whale stranding events 
and active sonar remain unknown, several authors have hypothesized that 
stranding events involving these species in the Bahamas and Canary 
Islands may have been triggered when the whales changed their dive 
behavior in a startled response to exposure to active sonar or to 
further avoid exposure (Cox et al., 2006; Rommel et al., 2006). These 
authors proposed three mechanisms by which the behavioral responses of 
beaked whales upon being exposed to active sonar might result in a 
stranding event. These include the following: gas bubble formation 
caused by excessively fast surfacing; remaining at the surface too long 
when tissues are supersaturated with nitrogen; or diving prematurely 
when extended time at the surface is necessary to eliminate excess 
nitrogen. More specifically, beaked whales that occur in deep waters 
that are in close proximity to shallow waters (for example, the 
``canyon areas'' that are cited in the Bahamas stranding event; see 
D'Spain and D'Amico, 2006), may respond to active sonar by swimming 
into shallow waters to avoid further exposures and strand if they were 
not able to swim back to deeper waters. Second, beaked whales exposed 
to active sonar might alter their dive behavior. Changes in their dive 
behavior might cause them to remain at the surface or at depth for 
extended periods of time which could lead to hypoxia directly by 
increasing their oxygen demands or indirectly by increasing their 
energy expenditures (to remain at depth) and increase their oxygen 
demands as a result. If beaked whales are at depth when they detect a 
ping from an active sonar transmission and change their dive profile, 
this could lead to the formation of significant gas bubbles, which 
could damage multiple organs or interfere with normal physiological 
function (Cox et al., 2006; Rommel et al., 2006; Zimmer and Tyack, 
2007). Baird et al. (2005) found that slow ascent rates from deep dives 
and long periods of time spent within 164 ft (50 m) of the surface were 
typical for both goose-beaked and Blainville's beaked whales, the two 
species involved in mass strandings related to naval sonar. These two 
behavioral mechanisms may be necessary to purge excessive dissolved 
nitrogen concentrated in their tissues during their frequent long dives 
(Baird et al., 2005). Baird et al. (2005) further suggests that 
abnormally rapid ascents or premature dives in response to high-
intensity sonar could indirectly result in physical harm to the beaked 
whales, through the mechanisms described above (gas bubble formation or 
non-elimination of excess nitrogen). In a review of the previously 
published data on the potential impacts of sonar on beaked whales, 
Bernaldo de Quir[oacute]s et al. (2019) suggested that the effect of 
MFAS on beaked whales varies among individuals or populations, and that 
predisposing conditions such as previous exposure to sonar and 
individual health risk factors may contribute to individual outcomes 
(such as decompression sickness).
    Because many species of marine mammals make repetitive and 
prolonged dives to great depths, it has long been assumed that marine 
mammals have evolved physiological mechanisms to protect against the 
effects of rapid and repeated decompressions. Although several 
investigators have identified physiological adaptations that may 
protect marine mammals against nitrogen gas supersaturation (alveolar 
collapse and elective circulation; Kooyman et al., 1972; Ridgway and 
Howard, 1979), Ridgway and Howard (1979) reported that bottlenose 
dolphins that were trained to dive repeatedly had muscle tissues that 
were substantially supersaturated with nitrogen gas. Houser et al. 
(2001b) used these data to model the accumulation of nitrogen gas 
within the muscle tissue of other marine mammal species and concluded 
that cetaceans that dive deep and have slow ascent or descent speeds 
would have tissues that are more supersaturated with nitrogen gas than 
other marine mammals. Based on these data, Cox et al. (2006) 
hypothesized that a critical dive sequence might make beaked whales 
more prone to stranding in response to acoustic exposures. The sequence 
began with (1) very deep (to depths as deep as 1.2 mi (2 km)) and long 
(as long as 90 minutes) foraging dives; (2) relatively slow, controlled 
ascents; and (3) a series of ``bounce'' dives between 328 and 1,312 ft 
(100 and 400 m) in depth (see Zimmer and Tyack, 2007). They concluded 
that acoustic exposures that disrupted any part of this dive sequence 
(for example, causing beaked whales to spend more time at surface 
without the bounce dives that are necessary to recover from the deep 
dive) could produce excessive levels of nitrogen supersaturation in 
their tissues, leading to gas bubble and emboli

[[Page 19943]]

formation that produces pathologies similar to decompression sickness.
    Zimmer and Tyack (2007) modeled nitrogen tension and bubble growth 
in several tissue compartments for several hypothetical dive profiles 
and concluded that repetitive shallow dives (defined as a dive where 
depth does not exceed the depth of alveolar collapse, approximately 236 
ft (72 m) for goose-beaked whale), perhaps as a consequence of an 
extended avoidance response to sonar sound, could pose a risk for 
decompression sickness and that this risk should increase with the 
duration of the response. Their models also suggested that 
unrealistically rapid rates of ascent from normal dive behaviors are 
unlikely to result in supersaturation to the extent that bubble 
formation would be expected. Tyack et al. (2006) suggested that emboli 
observed in animals exposed to mid-frequency range sonar (Jepson et 
al., 2003; Fernandez et al., 2005; Fern[aacute]ndez et al., 2012) could 
stem from a behavioral response that involves repeated dives shallower 
than the depth of lung collapse. Given that nitrogen gas accumulation 
is a passive process (i.e., nitrogen is metabolically inert), a 
bottlenose dolphin was trained to repetitively dive a profile predicted 
to elevate nitrogen saturation to the point that nitrogen bubble 
formation was predicted to occur. However, inspection of the vascular 
system of the dolphin via ultrasound did not demonstrate the formation 
of asymptomatic nitrogen gas bubbles (Houser et al., 2007). Baird et 
al. (2008), in a beaked whale tagging study off Hawaii, showed that 
deep dives are equally common during day or night, but ``bounce dives'' 
are typically a daytime behavior, possibly associated with visual 
predator avoidance. This may indicate that ``bounce dives'' are 
associated with something other than behavioral regulation of dissolved 
nitrogen levels, which would be necessary day and night.
    Additional predictive modeling conducted to date has been performed 
with many unknowns about the respiratory physiology of deep-diving 
breath-hold animals. For example, Denk et al. (2020) found intra-
species differences in the compliance of tracheobronchial structures of 
post-mortem cetaceans and pinnipeds under diving hydrostatic pressures, 
which would affect depth of alveolar collapse. Although, as 
hypothesized by Garcia Parraga et al. (2018) and reviewed in Fahlman et 
al., (2021), mechanisms may exist that allow marine mammals to create a 
pulmonary shunt without the need for hydrostatic pressure-induced lung 
collapse, i.e., by varying perfusion to the lung independent of lung 
collapse and degree of ventilation. If such a mechanism exists, then 
assumptions in prior gas models require reconsideration, the degree of 
nitrogen gas accumulation associated with dive profiles needs to be re-
evaluated, and behavioral responses potentially leading to a 
destabilization of the relationship between pulmonary ventilation and 
perfusion should be considered. Costidis and Rommel (2016) suggested 
that gas exchange may continue to occur across the tissues of air-
filled sinuses in deep diving odontocetes below the depth of lung 
collapse if hydrostatic pressures are high enough to drive gas exchange 
across into non-capillary veins.
    If marine mammals respond to an Action Proponent vessel that is 
transmitting active sonar in the same way that they might respond to a 
predator, their probability of flight responses could increase when 
they perceive that Action Proponent vessels are approaching them 
directly, because a direct approach may convey detection and intent to 
capture (Burger and Gochfeld, 1981, 1990; Cooper, 1997; Cooper, 1998). 
The probability of flight responses could also increase as received 
levels of active sonar increase (and the ship is, therefore, closer) 
and as ship speeds increase (that is, as approach speeds increase). For 
example, the probability of flight responses in Dall's sheep (Ovis 
dalli dalli) (Frid 2001a; Frid 2001b), ringed seals (Born et al., 
1999), Pacific brant (Branta bernicla nigricans) and Canada geese (B. 
canadensis) increased as a helicopter or fixed-wing aircraft approached 
groups of these animals more directly (Ward et al., 1999). Bald eagles 
(Haliaeetus leucocephalus) perched on trees alongside a river were also 
more likely to flee from a paddle raft when their perches were closer 
to the river or were closer to the ground (Steidl and Anthony, 1996).
    Despite the many theories involving bubble formation (both as a 
direct cause of injury, see Non-Auditory Injury section and an indirect 
cause of stranding), Southall et al. (2007) summarizes that there is 
either scientific disagreement or a lack of information regarding each 
of the following important points: (1) received acoustical exposure 
conditions for animals involved in stranding events; (2) pathological 
interpretation of observed lesions in stranded marine mammals; (3) 
acoustic exposure conditions required to induce such physical trauma 
directly; (4) whether noise exposure may cause behavioral responses 
(such as atypical diving behavior) that secondarily cause bubble 
formation and non-auditory injury; and (5) the extent the post mortem 
artifacts introduced by decomposition before sampling, handling, 
freezing, or necropsy procedures affect interpretation of observed 
lesions.
Strandings Associated With Explosive Use
Silver Strand (2011)--
    During a Navy training event on March 4, 2011, at the Silver Strand 
Training Complex in San Diego, California, three or possibly four 
dolphins were killed in an explosion. During an underwater detonation 
training event, a pod of 100 to 150 long-beaked common dolphins were 
observed moving towards the 700-yd (640.1-m) exclusion zone around the 
explosive charge, monitored by personnel in a safety boat and 
participants in a dive boat. Approximately 5 minutes remained on a 
time-delay fuse connected to a single 8.76 lb (3.97 kg) explosive 
charge (C-4 and detonation cord). Although the dive boat was placed 
between the pod and the explosive in an effort to guide the dolphins 
away from the area, that effort was unsuccessful and three long-beaked 
common dolphins near the explosion died. The Navy recovered those 
animals and transferred them to the local stranding network for 
necropsy. In addition to the three dolphins found dead on March 4, the 
remains of a fourth dolphin were discovered on March 7, 2011, near 
Oceanside, California (3 days later and approximately 42 mi (68 km) 
north of the detonation), which might also have been related to this 
event. Upon necropsy, all four animals were found to have sustained 
typical mammalian primary blast injuries (Danil and St Leger, 2011). 
Association of the fourth stranding with the training event is 
uncertain because dolphins strand on a regular basis in the San Diego 
area. Details such as the dolphins' depth and distance from the 
explosive at the time of the detonation could not be estimated from the 
250 yd (228.6 m) standoff point of the observers in the dive boat or 
the safety boat.
    These dolphin mortalities are the only known occurrence of a Navy 
training or testing event involving impulsive energy (underwater 
detonation) that caused mortality or injury to a marine mammal. Despite 
this being a rare occurrence, the Navy reviewed training requirements, 
safety procedures, and possible mitigation measures and implemented 
changes to reduce the potential for this to occur in the future.

[[Page 19944]]

Discussions of procedures associated with underwater explosives 
training and other training events are presented in the Proposed 
Mitigation Measures section.
Kyle of Durness, Scotland (2011)--
    On July 22, 2011, a mass stranding event involving long-finned 
pilot whales occurred at Kyle of Durness, Scotland. An investigation by 
Brownlow et al. (2015) considered unexploded ordnance detonation 
activities at a Ministry of Defense bombing range, conducted by the 
Royal Navy prior to and during the strandings, as a plausible 
contributing factor in the mass stranding event. While Brownlow et al. 
(2015) concluded that the serial detonations of underwater ordnance 
were an influential factor in the mass stranding event (along with the 
presence of a potentially compromised animal and navigational error in 
a topographically complex region), they also suggest that mitigation 
measures--which included observations from a zodiac only and by 
personnel not experienced in marine mammal observation, among other 
deficiencies--were likely insufficient to assess if cetaceans were in 
the vicinity of the detonations. The authors also cite information from 
the Ministry of Defense indicating ``an extraordinarily high level of 
activity'' (i.e., frequency and intensity of underwater explosions) on 
the range in the days leading up to the stranding.
Strandings on the Atlantic Coast and the Gulf of America
    Stranded marine mammals are reported along the entire Atlantic 
Coast and Gulf of America each year. Marine mammals strand due to 
natural or anthropogenic causes; the majority of reported type of 
occurrences in marine mammal strandings in this region include fishery 
interactions, illness, predation, and vessel strikes (Henry et al., 
2024). Stranding events that are associated with active UMEs on the 
Atlantic Coast and the Gulf of America (inclusive of the AFTT Study 
Area) were previously discussed in the Description of Marine Mammals in 
the Area of Specified Activities section.

Potential Effects of Vessel Strike

    Vessel strikes of marine mammals can result in death or serious 
injury of the animal. Wounds resulting from vessel strike may include 
massive trauma, hemorrhaging, broken bones, or propeller lacerations 
(Knowlton and Kraus, 2001). An animal at the surface could be struck 
directly by a vessel, a surfacing animal could hit the bottom of a 
vessel, or an animal just below the surface could be cut by a vessel's 
propeller. Superficial strikes may not kill or result in the death of 
the animal. Lethal interactions are typically associated with large 
whales, which are occasionally found draped across the bulbous bow of 
large commercial ships upon arrival in port. Although smaller cetaceans 
are more maneuverable in relation to large vessels than are large 
whales, they may also be susceptible to strike. The severity of 
injuries typically depends on the size and speed of the vessel 
(Knowlton and Kraus, 2001; Laist et al., 2001; Vanderlaan and Taggart, 
2007; Conn and Silber, 2013). Impact forces increase with speed, as 
does the probability of a strike at a given distance (Silber et al., 
2010; Gende et al., 2011).
    The most vulnerable marine mammals are those that spend extended 
periods of time at the surface in order to restore oxygen levels within 
their tissues after deep dives (e.g., the sperm whale; Jaquet & 
Whitehead, 1996; Watkins et al., 1999). Additionally, NARW mother-calf 
pairs spend 45 to 80 percent of their time surface resting or near-
surface feeding during the first nine months of the calf's life (Cusano 
et al., 2019), making them more susceptible to vessel strike. Further, 
some baleen whales seem generally unresponsive to vessel sound, making 
them more susceptible to vessel strikes (Nowacek et al., 2004). These 
species are primarily large, slow-moving whales. Marine mammal 
responses to vessels may include avoidance and changes in dive pattern 
(NRC, 2003).
    Wounds resulting from vessel strike may include massive trauma, 
hemorrhaging, broken bones, or propeller lacerations (Knowlton and 
Kraus, 2001). An animal at the surface could be struck directly by a 
vessel, a surfacing animal could hit the bottom of a vessel, or an 
animal just below the surface could be cut by a vessel's propeller. 
Impact forces increase with speed as does the probability of a strike 
at a given distance (Silber et al., 2010; Gende et al., 2011). An 
examination of all known vessel strikes from all shipping sources 
(civilian and military) indicates vessel speed is a principal factor in 
whether a vessel strike results in death or serious injury (Knowlton 
and Kraus, 2001; Laist et al., 2001; Jensen and Silber, 2003; Pace and 
Silber, 2005; Vanderlaan and Taggart, 2007). In assessing records in 
which vessel speed was known, Laist et al. (2001) found a direct 
relationship between the occurrence of a whale strike and the speed of 
the vessel involved in the collision. The authors concluded that most 
deaths occurred when a vessel was traveling in excess of 13 kn (24 km/
hr).
    Jensen and Silber (2003) detailed 292 records of known or probable 
vessel strikes of all large whale species from 1975 to 2002. Of these, 
vessel speed at the time of collision was reported for 58 cases. Of 
these 58 cases, 39 (or 67 percent) resulted in serious injury or death 
(19 of those resulted in serious injury as determined by blood in the 
water, propeller gashes or severed tailstock, and fractured skull, jaw, 
vertebrae, hemorrhaging, massive bruising or other injuries noted 
during necropsy and 20 resulted in death). Operating speeds of vessels 
that struck various species of large whales ranged from 2 to 51 kn (3.7 
to 94.5 km/hr). The majority (79 percent) of these strikes occurred at 
speeds of 13 kn (24 km/hr) or greater. The average speed that resulted 
in serious injury or death was 18.6 kn (34.4 km/hr). Pace and Silber 
(2005) found that the probability of death or serious injury increased 
rapidly with increasing vessel speed. Specifically, the predicted 
probability of serious injury or death increased from 45 to 75 percent 
as vessel speed increased from 10 to 14 kn (18.5 to 25.9 km/hr), and 
exceeded 90 percent at 17 kn (31.5 km/hr). Higher speeds during strikes 
result in greater force of impact and also appear to increase the 
chance of severe injuries or death. While modeling studies have 
suggested that hydrodynamic forces pulling whales toward the vessel 
hull increase with increasing speed (Clyne, 1999; Knowlton et al., 
1995), this is inconsistent with Silber et al. (2010), which 
demonstrated that there is no such relationship (i.e., hydrodynamic 
forces are independent of speed).
    In a separate study, Vanderlaan and Taggart (2007) analyzed the 
probability of lethal mortality of large whales at a given speed, 
showing that the greatest rate of change in the probability of a lethal 
injury to a large whale as a function of vessel speed occurs between 
8.6 and 15 kn (15.9 and 27.8 km/hr). The chances of a lethal injury 
decline from approximately 80 percent at 15 kn to approximately 20 
percent at 8.6 kn (15.9 km/hr). At speeds below 11.8 kn (21.9 km/hr), 
the chances of lethal injury drop below 50 percent, while the 
probability asymptotically increases toward 100 percent above 15 kn 
(27.8 km/hr). Garrison et al. (2025) reviewed and updated available 
data on whale-vessel interactions in U.S. waters to determine the 
effects of vessel speed and size on lethality of strikes of large 
whales, and found vessel size class had a significant effect on the 
probability of lethality. Decreasing vessel speeds

[[Page 19945]]

reduced the likelihood of a lethal outcome for all vessel size classes 
modeled, with the strongest effect for vessels less than 354 ft (108 m) 
long. Notably, the probability that a strike by a very large vessel 
(length) will be lethal exceeded 0.80 at all speeds greater than 5 kn 
(9.26 km/hr) (Garrison et al., 2025).
    The Jensen and Silber (2003) report notes that the database 
represents a minimum number of strikes, because the vast majority 
probably goes undetected or unreported. In contrast, Action Proponent 
vessels are likely to detect any strike that does occur because of the 
required personnel training and Lookouts (as described in the Proposed 
Mitigation Measures section), and they are required to report all 
vessel strikes involving marine mammals.
    In the AFTT Study Area, commercial traffic is heaviest in the 
nearshore waters, near major ports and in the shipping lanes along the 
entire U.S. East Coast and along the northern coast of the Gulf of 
America, while military vessel traffic is primarily concentrated 
between the mouth of the Chesapeake Bay and Jacksonville, Florida 
(Mintz, 2016). An examination of vessel traffic within the AFTT Study 
Area determined that military vessel occurrence is two orders of 
magnitude lower than that of commercial traffic. The study also 
revealed that while commercial traffic is relatively steady throughout 
the year, military vessel usage within the range complexes is episodic, 
based on specific exercises being conducted at different times of the 
year (Mintz, 2012); however, military vessel use within inshore waters 
occurs regularly and routinely consists of high-speed small craft 
movements. Juvenile whales of some species may be particularly 
vulnerable to vessel strikes due to their particular habitat use and 
surface foraging behavior in nearshore waters, where smaller vessel 
numbers are higher (Stepanuk et al., 2021).
    Over a period of 18 years from 1995 to 2012 there were a total of 
19 Navy vessel strikes in the AFTT Study Area. Eight of the strikes 
resulted in a confirmed death; but in 11 of the 19 strikes, the fate of 
the animal was unknown. It is possible that some of the 11 reported 
strikes resulted in recoverable injury or were not marine mammals at 
all, but another large marine species (e.g., basking shark). However, 
it is prudent to consider that all of the strikes could have resulted 
in the death of a marine mammal. From 2009 to 2024, there have been a 
total of three whale strikes by the U.S. Navy (one in 2011, two in 
2012), and three whale strikes by the U.S. Coast Guard (two in 2009, 
one in 2024) reported in the AFTT Study Area. In the 2009 Coast Guard 
strike of two whales, the whales were observed swimming away with no 
apparent injuries. All known strikes of large whales by the U.S. Navy 
and the U.S. Coast Guard in the AFTT Study Area have been in the 
VACAPES Operating Area. In 2021, a small Navy vessel struck a dolphin 
in Saint Andrew's Pass, Florida (offshore Panama City, Florida).
    Between 2007 and 2009, the Navy developed and distributed 
additional training, mitigation, and reporting tools to Navy operators 
to improve marine mammal protection and to ensure compliance with 
permit requirements. In 2009, the Navy implemented Marine Species 
Awareness Training designed to improve effectiveness of visual 
observation for marine mammals and other marine resources. In 
subsequent years, the Navy issued refined policy guidance on vessel 
strikes in order to collect the most accurate and detailed data 
possible in response to a possible incident (also see the Notification 
and Reporting Plan for this proposed rule). For over a decade, the Navy 
has implemented the Protective Measures Assessment Protocol software 
tool, which provides operators with notification of the required 
mitigation and a visual display of the planned training or testing 
activity location overlaid with relevant environmental data.

Marine Mammal Habitat

    The proposed training and testing activities could potentially 
affect marine mammal habitat through the introduction of impacts to the 
prey species of marine mammals, acoustic habitat (sound in the water 
column), water quality, and biologically important habitat for marine 
mammals. Each of these potential effects was considered in the 2024 
AFTT Draft Supplemental EIS/OEIS and was determined not to have adverse 
effects on marine mammal habitat. Based on the information below and 
the supporting information included in the 2024 AFTT Draft Supplemental 
EIS/OEIS, NMFS has determined that the proposed training and training 
activities would not have adverse or long-term impacts on marine mammal 
habitat.
Effects to Prey
    Sound may affect marine mammals through impacts on the abundance, 
behavior, or distribution of prey species (e.g., crustaceans, 
cephalopods, fish, zooplankton). Marine mammal prey varies by species, 
season, and location and, for some species, is not well-documented. 
Here, we describe studies regarding the effects of noise on known 
marine mammal prey.
    Fish utilize the soundscape and components of sound in their 
environment to perform important functions such as foraging, predator 
avoidance, mating, and spawning (e.g., Zelick et al., 1999; Fay, 2009). 
The most likely effects on fishes exposed to loud, intermittent, low-
frequency sounds are behavioral responses (i.e., flight or avoidance). 
Short duration, sharp sounds (such as pile driving or air guns) can 
cause overt or subtle changes in fish behavior and local distribution. 
The response of fish to acoustic sources depends on the physiological 
state of the fish, past exposures, motivation (e.g., feeding, spawning, 
migration), and other environmental factors. Key impacts to fishes may 
include behavioral responses, hearing damage, barotrauma (pressure-
related injuries), and mortality. While it is clear that the behavioral 
responses of individual prey, such as displacement or other changes in 
distribution, can have direct impacts on the foraging success of marine 
mammals, the effects on marine mammals of individual prey that 
experience hearing damage, barotrauma, or mortality is less clear, 
though obviously population scale impacts that meaningfully reduce the 
amount of prey available could have more serious impacts.
    Fishes, like other vertebrates, have a variety of different sensory 
systems to glean information from ocean around them (Astrup and Mohl, 
1993; Astrup, 1999; Braun and Grande, 2008; Carroll et al., 2017; 
Hawkins and Johnstone, 1978; Ladich and Popper, 2004; Ladich and 
Schulz-Mirbach, 2016; Mann, 2016; Nedwell et al., 2004; Popper et al., 
2003; Popper et al., 2005). Depending on their hearing anatomy and 
peripheral sensory structures, which vary among species, fishes hear 
sounds using pressure and particle motion sensitivity capabilities and 
detect the motion of surrounding water (Fay et al., 2008) (terrestrial 
vertebrates generally only detect pressure). Most marine fishes 
primarily detect particle motion using the inner ear and lateral line 
system, while some fishes possess additional morphological adaptations 
or specializations that can enhance their sensitivity to sound 
pressure, such as a gas-filled swim bladder (Braun and Grande, 2008; 
Popper and Fay, 2011). Hearing capabilities vary considerably between 
different fish species with data only available for just over 100 
species out of the 34,000 marine and freshwater fish species (Eschmeyer 
and Fong, 2016). In order to better understand acoustic

[[Page 19946]]

impacts on fishes, fish hearing groups are defined by species that 
possess a similar continuum of anatomical features which result in 
varying degrees of hearing sensitivity (Popper and Hastings, 2009a). 
There are four hearing groups defined for all fish species (modified 
from Popper et al., 2014) within this analysis and they include: fishes 
without a swim bladder (e.g., flatfish, sharks, rays, etc.); fishes 
with a swim bladder not involved in hearing (e.g., salmon, cod, 
pollock, etc.); fishes with a swim bladder involved in hearing (e.g., 
sardines, anchovy, herring, etc.); and fishes with a swim bladder 
involved in hearing and high-frequency hearing (e.g., shad and 
menhaden). Most marine mammal fish prey species would not be likely to 
perceive or hear mid- or high-frequency sonars. While hearing studies 
have not been done on sardines and northern anchovies, it would not be 
unexpected for them to possess hearing similarities to Pacific herring 
(up to 2-5 kHz) (Mann et al., 2005). Currently, less data are available 
to estimate the range of best sensitivity for fishes without a swim 
bladder.
    In terms of physiology, multiple scientific studies have documented 
a lack of mortality or physiological effects to fish from exposure to 
low- and mid-frequency sonar and other sounds (Halvorsen et al., 2012; 
J[oslash]rgensen et al., 2005; Juanes et al., 2017; Kane et al., 2010; 
Kvadsheim and Sevaldsen, 2005; Popper et al., 2007; Popper et al., 
2016; Watwood et al., 2016). Techer et al. (2017) exposed carp in 
floating cages for up to 30 days to low-power 23 and 46 kHz sources 
without any significant physiological response. Other studies have 
documented either a lack of TTS in species whose hearing range cannot 
perceive military sonar, or for those species that could perceive 
sonar-like signals, any TTS experienced would be recoverable (Halvorsen 
et al., 2012; Ladich and Fay, 2013; Popper and Hastings, 2009a, 2009b; 
Popper et al., 2014; Smith, 2016). Only fishes that have 
specializations that enable them to hear sounds above about 2,500 Hz 
(2.5 kHz) such as herring (Halvorsen et al., 2012; Mann et al., 2005; 
Mann, 2016; Popper et al., 2014) would have the potential to receive 
TTS or exhibit behavioral responses from exposure to mid-frequency 
sonar. In addition, any sonar induced TTS to fish whose hearing range 
could perceive sonar would only occur in the narrow spectrum of the 
source (e.g., 3.5 kHz) compared to the fish's total hearing range 
(e.g., 0.01 kHz to 5 kHz). Overall, military sonar sources are much 
narrower in terms of source frequency compared to a given fish species 
full hearing range (Halvorsen et al., 2012; J[oslash]rgensen et al., 
2005; Juanes et al., 2017; Kane et al., 2010; Kvadsheim & Sevaldsen, 
2005; Popper et al., 2007; Popper and Hawkins, 2016; Watwood et al., 
2016).
    In terms of behavioral responses, Juanes et al. (2017) discuss the 
potential for negative impacts from anthropogenic soundscapes on fish, 
but the author's focus was on broader based sounds such as ship and 
boat noise sources. Watwood et al. (2016) also documented no behavioral 
responses by reef fish after exposure to MFAS. Doksaeter et al. (2009; 
2012) reported no behavioral responses to mid-frequency military sonar 
by Atlantic herring; specifically, no escape responses (vertically or 
horizontally) were observed in free swimming herring exposed to mid-
frequency sonar transmissions. Based on these results (Doksaeter et 
al., 2009; Doksaeter et al., 2012; Sivle et al., 2012), Sivle et al. 
(2014) created a model in order to report on the possible population-
level effects on Atlantic herring from active naval sonar. The authors 
concluded that the use of military sonar poses little risk to 
populations of herring regardless of season, even when the herring 
populations are aggregated and directly exposed to sonar. Finally, 
Bruintjes et al. (2016) commented that fish exposed to any short-term 
noise within their hearing range might initially startle, but would 
quickly return to normal behavior. Occasional behavioral responses to 
intermittent explosions and impulsive sound sources are unlikely to 
cause long-term consequences for individual fish or populations. Fish 
that experience hearing loss as a result of exposure to explosions and 
impulsive sound sources may have a reduced ability to detect relevant 
sounds such as predators, prey, or social vocalizations. However, PTS 
has not been known to occur in fishes and any hearing loss in fish may 
be as temporary as the timeframe required to repair or replace the 
sensory cells that were damaged or destroyed (Popper et al., 2005; 
Popper et al., 2014; Smith et al., 2006). It is not known if damage to 
auditory nerve fibers could occur, and if so, whether fibers would 
recover during this process.
    It is also possible for fish to be injured or killed by an 
explosion in the immediate vicinity of the surface from dropped or 
fired ordnance, or near the bottom from shallow water bottom-placed 
underwater mine warfare detonations. Physical effects from pressure 
waves generated by underwater sounds (e.g., underwater explosions) 
could potentially affect fish within proximity of training or testing 
activities. SPLs of sufficient strength have been known to cause injury 
to fish and fish mortality (summarized in Popper et al., 2014). The 
shock wave from an underwater explosion is lethal to fish at close 
range, causing massive organ damage and non-auditory injury and 
internal bleeding (Keevin and Hempen, 1997). At greater distance from 
the detonation point, the extent of mortality or injury depends on a 
number of factors including fish size, body shape, orientation, and 
species (Keevin and Hempen, 1997; Wright, 1982). At the same distance 
from the source, larger fish are generally less susceptible to death or 
injury, elongated forms that are round in cross-section are less at 
risk than deep-bodied forms, and fish oriented sideways to the blast 
suffer the greatest impact (Edds-Walton and Finneran, 2006; O'Keeffe, 
1984; O'Keeffe and Young, 1984; Wiley et al., 1981; Yelverton et al., 
1975). Species with gas-filled organs are more susceptible to injury 
and mortality than those without them (Gaspin, 1975; Gaspin et al., 
1976; Goertner et al., 1994). Barotrauma injuries have been documented 
during controlled exposure to impact pile driving (an impulsive noise 
source, as are explosives and air guns) (Halvorsen et al., 2012b; 
Casper et al., 2013).
    Fish not killed or driven from a location by an explosion might 
change their behavior, feeding pattern, or distribution. Changes in 
behavior of fish have been observed as a result of sound produced by 
explosives, with effect intensified in areas of hard substrate (Wright, 
1982). However, Navy explosive use avoids hard substrate to the best 
extent practical during underwater detonations, or deep-water surface 
detonations. Stunning from pressure waves could also temporarily 
immobilize fish, making them more susceptible to predation. The 
abundances of various fish (and invertebrates) near the detonation 
point for explosives could be altered for a few hours before animals 
from surrounding areas repopulate the area. However, these populations 
would likely be replenished as waters near the detonation point are 
mixed with adjacent waters. Repeated exposure of individual fish to 
sounds from underwater explosions is not likely and exposures are 
expected to be short-term and localized. Long-term consequences for 
fish populations would not be expected. Several studies have 
demonstrated that air gun sounds might affect the distribution and 
behavior of

[[Page 19947]]

some fishes, potentially impacting foraging opportunities or increasing 
energetic costs (e.g., Fewtrell and McCauley, 2012; Pearson et al., 
1992; Skalski et al., 1992; Santulli et al., 1999; Paxton et al., 
2017).
    For fishes exposed to military sonar, there would be limited sonar 
use spread out in time and space across large offshore areas such that 
only small areas are actually ensonified (tens of miles) compared to 
the total life history distribution of fish prey species. There would 
be no probability for mortality or physical injury from sonar, and for 
most species, no or little potential for hearing or behavioral effects, 
except to a few select fishes with hearing specializations (e.g., 
herring) that could perceive mid-frequency sonar. Training and testing 
exercises involving explosions are dispersed in space and time; 
therefore, repeated exposure of individual fishes is unlikely. 
Mortality and injury effects to fishes from explosives would be 
localized around the area of a given in-water explosion, but only if 
individual fish and the explosive (and immediate pressure field) were 
co-located at the same time. Fishes deeper in the water column or on 
the bottom would not be affected by water surface explosions. Repeated 
exposure of individual fish to sound and energy from underwater 
explosions is not likely given fish movement patterns, especially 
schooling prey species. Most acoustic effects, if any, are expected to 
be short-term and localized. Long-term consequences for fish 
populations, including key prey species within the AFTT Study Area, 
would not be expected.
    Vessels and in-water devices do not normally collide with adult 
fish, particularly those that are common marine mammal prey, most of 
which can detect and avoid them. Exposure of fishes to vessel strike 
stressors is limited to those fish groups that are large, slow-moving, 
and may occur near the surface, such as ocean sunfish, whale sharks, 
basking sharks, and manta rays. With the exception of sturgeon, these 
species are distributed widely in offshore portions of the AFTT Study 
Area. Any isolated cases of a military vessel striking an individual 
could injure that individual, impacting the fitness of an individual 
fish. Vessel strikes would not pose a risk to most of the other marine 
fish groups, because many fish can detect and avoid vessel movements, 
making strikes rare and allowing the fish to return to their normal 
behavior after the ship or device passes. As a vessel approaches a 
fish, they could have a detectable behavioral or physiological response 
(e.g., swimming away and increased heart rate) as the passing vessel 
displaces them. However, such responses are not expected to have 
lasting effects on the survival, growth, recruitment, or reproduction 
of these marine fish groups at the population level and therefore would 
not have an impact on marine mammal species as prey items.
    In addition to fish, prey sources such as marine invertebrates 
could potentially be impacted by sound stressors as a result of the 
proposed activities. However, most marine invertebrates' ability to 
sense sounds is very limited. In most cases, marine invertebrates would 
not respond to impulsive and non-impulsive sounds, although they may 
detect and briefly respond to nearby low-frequency sounds. These short-
term responses would likely be inconsequential to invertebrate 
populations.
    Invertebrates appear to be able to detect sounds (Pumphrey, 1950; 
Frings and Frings, 1967) and are most sensitive to low-frequency sounds 
(Packard et al., 1990; Budelmann and Williamson, 1994; Lovell et al., 
2005; Mooney et al., 2010). Data on response of invertebrates such as 
squid, another marine mammal prey species, to anthropogenic sound is 
more limited (de Soto, 2016; Sole et al., 2017b). Data suggest that 
cephalopods are capable of sensing the particle motion of sounds and 
detect low frequencies up to 1-1.5 kHz, depending on the species, and 
so are likely to detect air gun noise (Kaifu et al., 2008; Hu et al., 
2009; Mooney et al., 2010; Samson et al., 2014). Sole et al. (2017b) 
reported physiological injuries to cuttlefish in cages placed at-sea 
when exposed during a controlled exposure experiment to low-frequency 
sources (315 Hz, 139 to 142 dB re 1 [mu]Pa\2\ and 400 Hz, 139 to 141 dB 
re 1 [mu]Pa\2\). Fewtrell and McCauley (2012) reported squids 
maintained in cages displayed startle responses and behavioral changes 
when exposed to seismic air gun sonar (136-162 re 1 [mu]Pa\2\s). 
However, the sources Sole et al. (2017a) and Fewtrell and McCauley 
(2012) used are not similar and were much lower than typical military 
sources within the AFTT Study Area. Nor do the studies address the 
issue of individual displacement outside of a zone of impact when 
exposed to sound. Jones et al. (2020) found that when squid 
(Doryteuthis (Amerigo) pealeii) were exposed to impulse pile driving 
noise, body pattern changes, inking, jetting, and startle responses 
were observed and nearly all squid exhibited at least one response. 
However, these responses occurred primarily during the first eight 
impulses and diminished quickly, indicating potential rapid, short-term 
habituation.
    Cephalopods have a specialized sensory organ inside the head called 
a statocyst that may help an animal determine its position in space 
(orientation) and maintain balance (Budelmann, 1992). Packard et al. 
(1990) showed that cephalopods were sensitive to particle motion, not 
sound pressure, and Mooney et al. (2010) demonstrated that squid 
statocysts act as an accelerometer through which particle motion of the 
sound field can be detected. Auditory injuries (lesions occurring on 
the statocyst sensory hair cells) have been reported upon controlled 
exposure to low-frequency sounds, suggesting that cephalopods are 
particularly sensitive to low-frequency sound (Andre et al., 2011; Sole 
et al., 2013). Behavioral responses, such as inking and jetting, have 
also been reported upon exposure to low-frequency sound (McCauley et 
al., 2000b; Samson et al., 2014). Squids, like most fish species, are 
likely more sensitive to low frequency sounds, and may not perceive 
mid- and high-frequency sonars such as military sonars. Cumulatively 
for squid as a prey species, individual and population impacts from 
exposure to military sonar and explosives, like fish, are not likely to 
be significant, and explosive impacts would be short-term and 
localized.
    Explosions and pile driving would likely kill or injure nearby 
marine invertebrates. Vessels also have the potential to impact marine 
invertebrates by disturbing the water column or sediments, or directly 
striking organisms (Bishop, 2008). The propeller wash (water displaced 
by propellers used for propulsion) from vessel movement and water 
displaced from vessel hulls can potentially disturb marine 
invertebrates in the water column and is a likely cause of zooplankton 
mortality (Bickel et al., 2011). The localized and short-term exposure 
to explosions or vessels could displace, injure, or kill zooplankton, 
invertebrate eggs or larvae, and macro-invertebrates. However, 
mortality or long-term consequences for a few animals is unlikely to 
have measurable effects on overall populations. Long-term consequences 
to marine invertebrate populations would not be expected as a result of 
exposure to sounds of vessels in the AFTT Study Area. Impacts to 
benthic communities from impulsive sound generated by active acoustic 
sound sources are not well documented. (e.g., Andriguetto-Filho et al., 
2005; Payne et al., 2007; 2008; Boudreau et al., 2009). There are no 
published data that indicate whether

[[Page 19948]]

temporary or permanent threshold shifts, auditory masking, or 
behavioral effects occur in benthic invertebrates (Hawkins et al., 
2014) and some studies showed no short-term or long-term effects of air 
gun exposure (e.g., Andriguetto-Filho et al., 2005; Payne et al., 2007; 
2008; Boudreau et al., 2009). Exposure to air gun signals was found to 
significantly increase mortality in scallops, in addition to causing 
significant changes in behavioral patterns during exposure (Day et al., 
2017). However, the authors state that the observed levels of mortality 
were not beyond naturally occurring rates. Explosions and pile driving 
could potentially kill or injure nearby marine invertebrates; however, 
mortality or long-term consequences for a few animals is unlikely to 
have measurable effects on overall populations.
    There is little information concerning potential impacts of noise 
on zooplankton populations. However, one study (McCauley et al., 2017) 
investigated zooplankton abundance, diversity, and mortality before and 
after exposure to air gun noise, finding that the mortality rate for 
zooplankton after air gun exposure was two to three times more compared 
with controls for all taxa. The majority of taxa present were copepods 
and cladocerans; for these taxa, the range within which effects on 
abundance were detected was up to approximately 0.75 mi (1.2 km). In 
order to have significant impacts on r-selected species (species that 
produce a large number of offspring and contribute few resources to 
each individual offspring) such as plankton, the spatial or temporal 
scale of impact must be large in comparison with the ecosystem 
concerned (McCauley et al., 2017).
    Notably, a recently described study produced results inconsistent 
with those of McCauley et al. (2017). Researchers conducted a field and 
laboratory study to assess if exposure to air gun noise affects 
mortality, predator escape response, or gene expression of the copepod 
Calanus finmarchicus (Fields et al., 2019). Immediate mortality of 
copepods was significantly higher, relative to controls, at distances 
of 16.4 ft (5 m) or less from the air guns. Mortality one week after 
the air gun blast was significantly higher in the copepods placed 32.8 
ft (10 m) from the air gun but was not significantly different from the 
controls at a distance of 65.6 ft (20 m) from the air gun. The increase 
in mortality, relative to controls, did not exceed 30 percent at any 
distance from the air gun. Moreover, the authors caution that even this 
higher mortality in the immediate vicinity of the air guns may be more 
pronounced than what would be observed in free-swimming animals due to 
increased flow speed of fluid inside bags containing the experimental 
animals. There were no sublethal effects on the escape performance or 
the sensory threshold needed to initiate an escape response at any of 
the distances from the air gun that were tested. Whereas McCauley et 
al. (2017) reported an SEL of 156 dB at a range of 1,670-2,158.8 ft 
(509-658 m), with zooplankton mortality observed at that range, Fields 
et al. (2019) reported an SEL of 186 dB at a range of 82 ft (25 m), 
with no reported mortality at that distance. The large scale of effect 
observed here is of concern--particularly where repeated noise exposure 
is expected--and further study is warranted.
    Military expended materials resulting from training and testing 
activities could potentially result in minor long-term changes to 
benthic habitat, however the impacts of small amounts of expended 
materials are unlikely to have measurable effects on overall 
populations. Military expended materials may be colonized over time by 
benthic organisms that prefer hard substrate and would provide 
structure that could attract some species of fish or invertebrates.
    Overall, the combined impacts of sound exposure, explosions, vessel 
strikes, and military expended materials resulting from the proposed 
activities would not be expected to have measurable effects on 
populations of marine mammal prey species. Prey species exposed to 
sound might move away from the sound source, experience TTS, experience 
masking of biologically relevant sounds, or show no obvious direct 
effects. Mortality from decompression injuries is possible in close 
proximity to a sound, but only limited data on mortality in response to 
air gun noise exposure are available (Fields et al., 2019, Hawkins et 
al., 2014, McCauley et al., 2017). The most likely impacts for most 
prey species in a given area would be temporary avoidance of the area. 
Surveys using towed air gun arrays move through an area relatively 
quickly, limiting exposure to multiple impulsive sounds. In all cases, 
sound levels would return to ambient once a survey ends and the noise 
source is shut down and, when exposure to sound ends, behavioral and/or 
physiological responses are expected to end relatively quickly 
(McCauley et al., 2000b). The duration of fish avoidance of a given 
area after survey effort stops is unknown, but a rapid return to normal 
recruitment, distribution, and behavior is anticipated. While the 
potential for disruption of spawning aggregations or schools of 
important prey species can be meaningful on a local scale, the mobile 
and temporary nature of most surveys and the likelihood of temporary 
avoidance behavior suggest that impacts would be minor. Long-term 
consequences to marine invertebrate populations would not be expected 
as a result of exposure to sounds or vessels in the AFTT Study Area.
Acoustic Habitat
    Acoustic habitat is the soundscape which encompasses all of the 
sound present in a particular location and time, as a whole when 
considered from the perspective of the animals experiencing it. Animals 
produce sound for, or listen for sounds produced by, conspecifics 
(communication during feeding, mating, and other social activities), 
other animals (finding prey or avoiding predators), and the physical 
environment (finding suitable habitats, navigating). Together, sounds 
made by animals and the geophysical environment (e.g., produced by 
earthquakes, lightning, wind, rain, waves) make up the natural 
contributions to the total acoustics of a place. These acoustic 
conditions, termed acoustic habitat, are one attribute of an animal's 
total habitat.
    Soundscapes are also defined by, and acoustic habitat influenced 
by, the total contribution of anthropogenic sound. This may include 
incidental emissions from sources such as vessel traffic or may be 
intentionally introduced to the marine environment for data acquisition 
purposes (as in the use of air gun arrays) or for military training and 
testing purposes (as in the use of sonar and explosives and other 
acoustic sources). Anthropogenic noise varies widely in its frequency, 
content, duration, and loudness, and these characteristics greatly 
influence the potential habitat-mediated effects to marine mammals 
(please also see the previous discussion in the Masking section), which 
may range from local effects for brief periods of time to chronic 
effects over large areas and for long durations. Depending on the 
extent of effects to habitat, animals may alter their communications 
signals (thereby potentially expending additional energy) or miss 
acoustic cues (either conspecific or adventitious). Problems arising 
from a failure to detect cues are more likely to occur when noise 
stimuli are chronic and overlap with biologically relevant cues used 
for communication, orientation, and predator/prey detection (Francis 
and Barber, 2013). For more detail on these concepts see, e.g., Barber 
et al., 2009; Pijanowski et al., 2011; Francis and Barber, 2013; Lillis 
et al., 2014.

[[Page 19949]]

    The term ``listening area'' refers to the region of ocean over 
which sources of sound can be detected by an animal at the center of 
the space. Loss of communication space concerns the area over which a 
specific animal signal (used to communicate with conspecifics in 
biologically important contexts such as foraging or mating) can be 
heard, in noisier relative to quieter conditions (Clark et al., 2009). 
Lost listening area concerns the more generalized contraction of the 
range over which animals would be able to detect a variety of signals 
of biological importance, including eavesdropping on predators and prey 
(Barber et al., 2009). Such metrics do not, in and of themselves, 
document fitness consequences for the marine animals that live in 
chronically noisy environments. Long-term population-level consequences 
mediated through changes in the ultimate survival and reproductive 
success of individuals are difficult to study, and particularly so 
underwater. However, it is increasingly well documented that aquatic 
species rely on qualities of natural acoustic habitats, with 
researchers quantifying reduced detection of important ecological cues 
(e.g., Francis and Barber, 2013; Slabbekoorn et al., 2010) as well as 
survivorship consequences in several species (e.g., Simpson et al., 
2014; Nedelec et al., 2015).
    The sounds produced during training and testing activities can be 
widely dispersed or concentrated in small areas for varying periods. 
Sound produced from training and testing activities in the AFTT Study 
Area is temporary and transitory. Any anthropogenic noise attributed to 
training and testing activities in the AFTT Study Area would be 
temporary and the affected area would be expected to immediately return 
to the original state when these activities cease.
Water Quality
    Training and testing activities may introduce water quality 
constituents into the water column. Based on the analysis of the 2024 
AFTT Draft Supplemental EIS/OEIS, military expended materials (e.g., 
undetonated explosive materials) would be released in quantities and at 
rates that would not result in a violation of any water quality 
standard or criteria. NMFS has reviewed this analysis and concurs that 
it reflects the best available science. High-order explosions consume 
most of the explosive material, creating typical combustion products. 
For example, in the case of Royal Demolition Explosive, 98 percent of 
the products are common seawater constituents and the remainder is 
rapidly diluted below threshold effect level. Explosion by-products 
associated with high order detonations present no secondary stressors 
to marine mammals through sediment or water. However, low order 
detonations and unexploded ordnance present elevated likelihood of 
impacts on marine mammals.
    Indirect effects of explosives and unexploded ordnance to marine 
mammals via sediment is possible in the immediate vicinity of the 
ordnance. Degradation products of Royal Demolition Explosive are not 
toxic to marine organisms at realistic exposure levels (Rosen and 
Lotufo, 2010). Relatively low solubility of most explosives and their 
degradation products means that concentrations of these contaminants in 
the marine environment are relatively low and readily diluted. 
Furthermore, while explosives and their degradation products were 
detectable in marine sediment approximately 6-12 inches (0.15-0.3 m) 
away from degrading ordnance, the concentrations of these compounds 
were not statistically distinguishable from background beyond 3-6 ft 
(1-2 m) from the degrading ordnance. Taken together, it is possible 
that marine mammals could be exposed to degrading explosives, but it 
would be within a very small radius of the explosive (1-6 ft (0.3-2 
m)).
    Equipment used by the Action Proponents within the AFTT Study Area, 
including ships and other marine vessels, aircraft, and other 
equipment, are also potential sources of by-products. All equipment is 
properly maintained in accordance with applicable Navy, Coast Guard and 
legal requirements. All such operating equipment meets Federal water 
quality standards, where applicable.

Estimated Take of Marine Mammals

    This section indicates the number of takes that NMFS is proposing 
to authorize, which is based on the amount of take that NMFS 
anticipates is reasonably likely to occur. NMFS coordinated closely 
with the Action Proponents in the development of their incidental take 
application, and preliminarily agrees that the methods the Action 
Proponents have put forth described herein to estimate take (including 
the model, thresholds, and density estimates), and the resulting 
numbers are based on the best available science and appropriate for 
authorization.
    Takes would be predominantly in the form of harassment, but a small 
number of mortalities are also possible. For this military readiness 
activity, the MMPA defines ``harassment'' as (i) Any act that injures 
or has the significant potential to injure a marine mammal or marine 
mammal stock in the wild (Level A harassment); or (ii) Any act that 
disturbs or is likely to disturb a marine mammal or marine mammal stock 
in the wild by causing disruption of natural behavioral patterns, 
including, but not limited to, migration, surfacing, nursing, breeding, 
feeding, or sheltering, to a point where the behavioral patterns are 
abandoned or significantly altered (Level B harassment).
    Proposed authorized takes would primarily be in the form of Level B 
harassment, as use of the acoustic (e.g., active sonar, pile driving, 
and seismic air guns) and explosive sources is most likely to result in 
disruption of natural behavioral patterns to a point where they are 
abandoned or significantly altered (as defined specifically at the 
beginning of this section, but referred to generally as behavioral 
disturbance) for marine mammals, either via direct behavioral 
disturbance or TTS. There is also the potential for Level A harassment, 
in the form of auditory injury to result from exposure to the sound 
sources utilized in military readiness activities. Lastly, no more than 
6 serious injuries or mortalities total (over the 7-year period) of 
large whales could potentially occur through vessel strikes, and 13 
serious injuries or mortalities (over the 7-year period) from explosive 
use. Although we analyze the impacts of these potential serious 
injuries or mortalities that are proposed for authorization, the 
proposed mitigation and monitoring measures are expected to minimize 
the likelihood (i.e., further lower the already low probability) that 
vessel strike (and the associated serious injury or mortality) would 
occur, as well as the severity of other takes.
    Generally speaking, for acoustic impacts NMFS estimates the amount 
and type of harassment by considering: (1) acoustic thresholds above 
which NMFS believes the best available science indicates marine mammals 
would experience behavioral disturbance or incur some degree of 
temporary or permanent hearing impairment; (2) the area or volume of 
water that would be ensonified above these levels in a day or event; 
(3) the density or occurrence of marine mammals within these ensonified 
areas; and (4) the number of days of activities or events.

Acoustic Thresholds

    Using the best available science, NMFS, in coordination with the 
Navy, has established acoustic thresholds that identify the most 
appropriate received

[[Page 19950]]

level of underwater sound above which marine mammals exposed to these 
sound sources could be reasonably expected to directly incur a 
disruption in behavior patterns to a point where they are abandoned or 
significantly altered (equated to onset of Level B harassment), or to 
incur TTS onset (equated to Level B harassment via the indirect 
disruptions of behavioral patterns) or AUD INJ onset (equated to Level 
A harassment). Thresholds have also been developed to identify the 
pressure and impulse levels above which animals may incur non-auditory 
injury or mortality from exposure to explosive detonation.
Hearing Impairment (TTS/AUD INJ), Non-Auditory Injury, and Mortality
    NMFS' 2024 Technical Guidance (NMFS, 2024) identifies dual criteria 
to assess AUD INJ (Level A harassment) to five different marine mammal 
groups (based on hearing sensitivity) as a result of exposure to noise 
from two different types of sources (impulsive or non-impulsive). The 
Updated Technical Guidance also identifies criteria to predict TTS, 
which is not considered injury and falls into the Level B harassment 
category. The Action Proponents' specified activities include the use 
of non-impulsive (sonar, vibratory pile driving) and impulsive 
(explosives, air guns, impact pile driving) sources.
    For the consideration of impacts on hearing in Phase IV, marine 
mammals were divided into nine groups for analysis: very low-frequency 
cetaceans (VLF), low-frequency cetaceans (LF), high-frequency cetaceans 
(HF), very high-frequency cetaceans (VHF), sirenians (SI), phocid 
carnivores in water and in air (PCW and PCA, respectively), and 
otariids and other non-phocid marine carnivores in water and air (OCW 
and OCA, respectively). For each group, a frequency-dependent weighting 
function and numeric thresholds for the onset of TTS and the onset of 
AUD INJ were estimated. The onset of TTS is defined as a TTS of 6 dB 
measured approximately 2-5 minutes after exposure. A TTS of 40 dB is 
used as a proxy for the onset of AUD INJ; i.e., it is assumed that 
exposures beyond those capable of causing 40 dB of TTS have the 
potential to result in PTS or other auditory injury (e.g., loss of 
cochlear neuron synapses). Exposures just sufficient to cause TTS or 
AUD INJ are denoted as ``TTS onset'' or ``AUD INJ onset'' exposures. 
Onset levels are treated as step functions or ``all-or-nothing'' 
thresholds: exposures above the TTS or AUD INJ onset level are assumed 
to always result in TTS or AUD INJ, while exposures below the TTS or 
AUD INJ onset level are assumed to not cause TTS or AUD INJ. For non-
impulsive exposures, onset levels are specified in frequency-weighted 
sound exposure level (SEL); for impulsive exposures, dual metrics of 
weighted SEL and unweighted peak sound pressure level (SPL) are used.
    To compare Phase IV weighting functions and TTS/AUD INJ SEL 
thresholds to those used in Phase III, both the weighting function 
shape and the weighted threshold values were considered; the weighted 
thresholds by themselves only indicate the TTS/AUD INJ threshold at the 
most susceptible frequency (based on the relevant weighting function). 
In contrast, the TTS/AUD INJ exposure functions incorporate both the 
shape of the weighting function and the weighted threshold value and 
provide the best means of comparing the frequency-dependent TTS/AUD INJ 
thresholds for Phase III and Phase IV.
    The most significant differences between the Phase III and Phase IV 
functions and thresholds include the following:
    (1) Mysticetes were divided into two groups (VLF and LF), with the 
upper hearing limit for the LF group increased from Phase III to match 
recent hearing measurements in minke whales (Houser et al., 2024);
    (2) Group names were changed from Phase III to be consistent with 
Southall et al. (2019). Specifically, the Phase III mid-frequency (MF) 
cetacean group is now designated as the high-frequency (HF) cetacean 
group, and the group previously designated as high-frequency (HF) 
cetaceans is now the very-high frequency (VHF) cetacean group;
    (3) For the HF group, Phase IV onset TTS/AUD INJ thresholds are 
lower compared to Phase III at frequencies below approximately 10 kHz. 
This is a result of new TTS onset data for dolphins at low frequencies 
(Finneran et al., 2023);
    (4) For the PCW group, new TTS data for harbor seals (Kastelein et 
al., 2020b; Kastelein et al., 2020e) resulted in slightly lower TTS/AUD 
INJ thresholds at high frequencies compared to Phase III; and
    (5) For group OCW, new TTS data for California sea lions (Kastelein 
et al., 2021b; Kastelein et al., 2022a, 2022b) resulted in 
significantly lower TTS/AUD INJ thresholds compared to Phase III.
    Of note, the thresholds and weighting function for the LF cetacean 
hearing group in NMFS' 2024 Technical Guidance (NMFS, 2024) match the 
Navy's VLF cetacean hearing group. However, the weighting function for 
those hearing groups differs between the two documents (i.e., the 
Navy's LF cetacean group has a different weighting function from NMFS) 
due to the Houser et al. (2024) minke whale data incorporated into Navy 
2024, but not NMFS (2024). While NMFS' 2024 Technical Guidance differs 
from the criteria that the Action Proponents used to assess AUD INJ and 
TTS for low-frequency cetaceans, NMFS concurs that the criteria the 
Action Proponents applied are appropriate for assessing the impacts of 
their proposed action. The criteria used by the Action Proponents are 
conservative in that those criteria show greater sensitivity at higher 
frequencies (i.e., application of those criteria result in a higher 
amount of estimated take by higher frequency sonars than would result 
from application of NMFS' 2024 Technical Guidance) which is where more 
of the take is expected.
    These thresholds (table 17 and table 18) were developed by 
compiling and synthesizing the best available science and soliciting 
input multiple times from both public and peer reviewers. The 
references, analysis, and methodology used in the development of the 
thresholds are described in Updated Technical Guidance, which may be 
accessed at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

 Table 17--Acoustic Thresholds Identifying the Onset of TTS and AUD INJ
       for Non-Impulsive Sound Sources by Functional Hearing Group
------------------------------------------------------------------------
                                                             AUD INJ
                Group                   TTS threshold     threshold SEL
                                       SEL (weighted)      (weighted)
------------------------------------------------------------------------
Very low-frequency (VLF)............               177               197
Low-frequency (LF)..................               177               197

[[Page 19951]]

 
High-frequency (HF).................               181               201
Very high-frequency (VHF)...........               161               181
Otariid carnivores in water (OW)....               179               199
Phocid carnivores in water (PW).....               175               195
------------------------------------------------------------------------
Note: SEL thresholds in dB re 1 [mu]Pa\2\s underwater.

    Based on the best available science, the Action Proponents (in 
coordination with NMFS) used the acoustic and pressure thresholds 
indicated in table 17 to predict the onset of behavioral harassment, 
AUD INJ, TTS, non-auditory injury, and mortality due to explosive 
sources.
    For explosive activities using single detonations (i.e., no more 
than one detonation within a day), such as those described in the 
proposed activity, NMFS uses TTS onset thresholds to assess the 
likelihood of behavioral harassment, rather than the Level B harassment 
threshold for multiple detonations indicated in table 18. While marine 
mammals may also respond to single explosive detonations, these 
responses are expected to more typically be in the form of startle 
response, rather than a more meaningful disruption of a behavioral 
pattern. On the rare occasion that a single detonation might result in 
a behavioral response that qualifies as Level B harassment, it would be 
expected to be in response to a comparatively higher received level. 
Accordingly, NMFS considers the potential for these responses to be 
quantitatively accounted for through the application of the TTS 
criteria, which, as noted above, is 5 dB higher than the behavioral 
harassment threshold for multiple explosives.

                Table 18--Explosive Thresholds for Marine Mammals for AUD INJ, TTS, and Behavior
                                             [Multiple detonations]
----------------------------------------------------------------------------------------------------------------
                                          AUD INJ impulsive     TTS impulsive threshold    Behavioral threshold
            Hearing group                    threshold *                   *              (multiple detonations)
----------------------------------------------------------------------------------------------------------------
Very Low-Frequency (VLF)/Low-          Cell 1: Lpk,flat: 222    Cell 2: Lpk,flat: 216    Cell 3: LE,LF,24h: 163
 Frequency (LF) Cetaceans.              dB; LE,LF,24h: 183 dB.   dB LE,LF,24h: 168 dB.    dB.
High-Frequency (HF) Cetaceans........  Cell 4: Lpk,flat: 230    Cell 5: Lpk,flat: 224    Cell 6: LE,HF,24h: 173
                                        dB LE,HF,24h: 193 dB.    dB LE,HF,24h: 178 dB.    dB.
Very High-Frequency (VHF) Cetaceans..  Cell 7: Lpk,flat: 202    Cell 8: Lpk,flat: 196    Cell 9: LE,VHF,24h: 139
                                        dB LE,VHF,24h: 159 dB.   dB LE,VHF,24h: 144 dB.   dB.
Phocid Pinnipeds (PW) (Underwater)...  Cell 10: Lpk,flat: 223   Cell 11: Lpk,flat: 217   Cell 12: LE,PW,24h: 163
                                        dB LE,PW,24h: 183 dB.    dB LE,PW,24h: 168 dB.    dB.
Otariid Pinnipeds (OW) (Underwater)..  Cell 13: Lpk,flat: 230   Cell 14: Lpk,flat: 224   Cell 15: LE,OW,24h: 165
                                        dB LE,OW,24h: 185 dB.    dB LE,OW,24h: 170 dB.    dB.
----------------------------------------------------------------------------------------------------------------
Note: Peak sound pressure level (Lp,0-pk) has a reference value of 1 [micro]Pa, and weighted cumulative sound
  exposure level (LE,p) has a reference value of 1 [micro]Pa\2\s. In this Table, criteria are abbreviated to be
  more reflective of International Organization for Standardization standards (ISO, 2017; ISO, 2020). The
  subscript ``flat'' is being included to indicate peak sound pressure are flat weighted or unweighted within
  the generalized hearing range of marine mammals underwater (i.e., 7 Hz to 165 kHz). The subscript associated
  with cumulative sound exposure level criteria indicates the designated marine mammal auditory weighting
  function (LF, HF, and VHF cetaceans, and PW and OW pinnipeds) and that the recommended accumulation period is
  24 hours. The weighted cumulative sound exposure level criteria could be exceeded in a multitude of ways
  (i.e., varying exposure levels and durations, duty cycle). When possible, it is valuable for action proponents
  to indicate the conditions under which these criteria will be exceeded.
* Dual metric criteria for impulsive sounds: Use whichever criteria results in the larger isopleth for
  calculating AUD INJ onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure
  level criteria associated with impulsive sounds, the PK SPL criteria are recommended for consideration for non-
  impulsive sources.

    The criterion for mortality is based on severe lung injury observed 
in terrestrial mammals exposed to underwater explosions as recorded in 
Goertner (1982). The criteria for non-auditory injury are based on 
slight lung injury or gastrointestinal (G.I.) tract injury observed in 
the same data set. Mortality and slight lung injury impacts to marine 
mammals are estimated using impulse thresholds based on both calf/pup/
juvenile and adult masses (see the ``Criteria and Thresholds for U.S. 
Navy Acoustic and Explosive Effects Analysis (Phase 4)'' technical 
report (U.S. Department of the Navy, 2024)). The peak pressure 
threshold applies to all species and age classes. Unlike the prior 
analysis (Phase III), this analysis relies on the onset rather than the 
mean estimated threshold for these effects. This revision results in a 
small increase in the predicted non-auditory injuries and mortalities 
for the same event versus prior analyses. Thresholds are provided in 
table 19 for use in non-auditory injury assessment for marine mammals 
exposed to underwater explosives.

[[Page 19952]]



                       Table 19--Non-Auditory Injury Thresholds for Underwater Explosives
----------------------------------------------------------------------------------------------------------------
            Hearing group                Mortality-Impulse *         Injury-Impulse *      Injury-Peak pressure
----------------------------------------------------------------------------------------------------------------
All Marine Mammals..................  Cell 1: Modified Goertner  Cell 2: Modified         Cell 3: Lp,0-pk,flat:
                                       model; Equation 1.         Goertner model;          237 dB.
                                                                  Equation 2.
----------------------------------------------------------------------------------------------------------------
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa. In this table, thresholds are abbreviated
  to reflect ANSI (2013). However, ANSI defines peak sound pressure as incorporating frequency weighting, which
  is not the intent for this Technical Guidance. Hence, the subscript ``flat'' is being included to indicate
  peak sound pressure should be flat weighted or unweighted within the overall marine mammal generalized hearing
  range.
* Lung injury (severe and slight) thresholds are dependent on animal mass (Recommendation: table C.9 from U.S.
  Department of the Navy (2017) based on adult and/or calf/pup mass by species).
Modified Goertner Equations for severe and slight lung injury (pascal-second):
 
Equation 1: 103M\1/3\(1 + D/10.1)\1/6\ Pa-s
Equation 2: 47.5M\1/3\(1 + D/10.1)\1/6\ Pa-s
 
M animal (adult and/or calf/pup) mass (kg) (table C.9 in DoN 2017).
D animal depth (meters).

Level B Harassment by Behavioral Disturbance
    Though significantly driven by received level and distance, the 
onset of Level B harassment by behavioral disturbance from 
anthropogenic noise exposure is also informed to varying degrees by 
other factors and can be difficult to predict (Southall et al., 2007, 
Ellison et al., 2012). As discussed in the Potential Effects of 
Specified Activities on Marine Mammals and Their Habitat section, 
marine mammal responses to sound (some of which are considered 
disturbances that rise to the level of a take) are highly variable and 
context specific, i.e., they are affected by differences in acoustic 
conditions; differences between species and populations; differences in 
gender, age, reproductive status, or social behavior; and other prior 
experience of the individuals. This means there is support for 
considering alternative approaches for estimating Level B behavioral 
harassment. Although the statutory definition of Level B harassment for 
military readiness activities means that a natural behavior pattern of 
a marine mammal is significantly altered or abandoned, the current 
state of science for determining those thresholds is somewhat 
unsettled.
    Despite the rapidly evolving science, there are still challenges in 
quantifying expected behavioral responses that qualify as take by Level 
B harassment, especially where the goal is to use one or two 
predictable indicators (e.g., received level and distance) to predict 
responses that are also driven by additional factors that cannot be 
easily incorporated into the thresholds (e.g., context). So, while the 
criteria that identify Level B harassment by behavioral disturbance 
(referred to as ``behavioral harassment thresholds'') have been refined 
to better consider the best available science (e.g., incorporating both 
received level and distance), they also still have some built-in 
factors to address the challenge noted. For example, while duration of 
observed responses in the data are now considered in the thresholds, 
some of the responses that are informing take thresholds are of a very 
short duration, such that it is possible some of these responses might 
not always rise to the level of disrupting behavior patterns to a point 
where they are abandoned or significantly altered. We describe the 
application of this behavioral harassment threshold as identifying the 
maximum number of instances in which marine mammals could be reasonably 
expected to experience a disruption in behavior patterns to a point 
where they are abandoned or significantly altered. In summary, we 
believe these behavioral harassment criteria are the most appropriate 
method for predicting Level B harassment by behavioral disturbance 
given the best available science and the associated uncertainty.
Sonar--
    In its analysis of impacts associated with sonar acoustic sources 
(which was coordinated with NMFS), the Action Proponents used an 
updated approach, as described below. Many of the behavioral responses 
identified using the Action Proponents' quantitative analysis are most 
likely to be of moderate severity as described in the Southall et al. 
(2021) behavioral response severity scale. These ``moderate'' severity 
responses were considered significant if they were sustained for the 
duration of the exposure or longer. Within the Action Proponents' 
quantitative analysis, many responses are predicted from exposure to 
sound that may exceed an animal's Level B behavioral harassment 
threshold for only a single exposure (a few seconds) to several 
minutes, and it is likely that some of the resulting estimated 
behavioral responses that are counted as Level B harassment would not 
constitute ``significantly altering or abandoning natural behavioral 
patterns,'' i.e., the estimated number of takes by Level B harassment 
due to behavioral disturbance and response is likely somewhat of an 
overestimate.
    As noted above, the Action Proponents coordinated with NMFS to 
develop behavioral harassment thresholds specific to their military 
readiness activities utilizing active sonar that identify at what 
received level and distance Level B harassment by behavioral 
disturbance would be expected to result. These behavioral harassment 
thresholds consist of behavioral response functions (BRFs) and 
associated distance cut-off conditions, and are also referred to, 
together, as ``the criteria.'' These criteria are used to estimate the 
number of animals that may exhibit a behavioral response that rises to 
the level of a take when exposed to sonar and other transducers. The 
way the criteria were derived is discussed in detail in the ``Criteria 
and Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis 
(Phase 4)'' technical report (U.S. Department of the Navy, 2024). 
Developing these behavioral harassment criteria involved multiple 
steps. All peer-reviewed published behavioral response studies 
conducted both in the field and on captive animals were examined in 
order to understand the breadth of behavioral responses of marine 
mammals to sonar and other transducers. Marine mammals were divided 
into four groups for analysis: mysticetes (all baleen whales), 
odontocetes (most toothed whales, dolphins, and porpoises), sensitive 
species (beaked whales and harbor porpoise), and pinnipeds (true seals, 
sea lions, walruses, sea otters, polar bears). These groups are like 
the groups used in the behavioral response analysis (Phase III), with 
the exception of combining beaked whales and harbor porpoise into a 
single curve. For each group, a biphasic BRF was developed using the

[[Page 19953]]

best available data and Bayesian dose response models developed at the 
University of St. Andrews. The BRF base probability of response on the 
highest SPL (rms) received level.
    The analysis of BRFs differs from the previous phase (Phase III) 
due to the addition of new data and the separation of some species 
groups. The Sensitive Species BRF is more sensitive at lower received 
levels but less sensitive at higher received levels than the prior 
beaked whale and harbor porpoise functions. The Odontocete BRF is less 
sensitive across all received levels due to including additional 
behavioral response research, which will result in a lower number of 
behavioral responses than in the prior analysis for the same event, but 
also reduces the avoidance of auditory effects. The Pinnipeds (in-
water) BRF is more sensitive due to the inclusion of additional captive 
pinniped data (only three behavioral studies using captive pinnipeds 
were available for the derivation of the BRF). Behavioral studies of 
captive animals can be difficult to extrapolate to wild animals due to 
several factors (e.g., use of trained subjects). This means the 
pinniped BRF likely overestimates effects compared to observed 
responses of wild pinnipeds to sound and anthropogenic activity. The 
Mysticete BRF is less sensitive across most received levels due to 
including additional behavioral response research. This will result in 
a lower number of behavioral responses than in the prior analysis for 
the same event, but also reduces the avoidance of auditory effects.
    The BRFs only relate the highest received level of sound to the 
probability that an animal will have a behavioral response. The BRFs do 
not account for the duration or pattern of use of any individual sound 
source or of the activity as a whole; the number of sound sources that 
may be operating simultaneously; or how loud the animal may perceive 
the sonar signal to be based on the frequency of the sonar versus the 
animal's hearing range.
    Criteria for assessing marine mammal behavioral responses to sonars 
use the metric of highest received sound level (rms) to evaluate the 
risk of immediate responses by exposed animals. Currently, there are 
limited data to develop criteria that include the context of an 
exposure, characteristics of individual animals, behavioral state, 
duration of an exposure, sound source duty cycle, and the number of 
individual sources in an activity (although these factors certainly 
influence the severity of a behavioral response) and, further, even 
where certain contextual factors may be predictive where known, it is 
difficult to reliably predict when such factors will be present.
    The BRFs also do not account for distance. At moderate to low 
received levels the correlation between probability of response and 
received level is very poor and it appears that other variables mediate 
behavioral responses (e.g., Ellison et al., 2011) such as the distance 
between the animal and the sound source. For this analysis, distance 
between the animal and the sound source (i.e., range) was initially 
included, however, range was too confounded with received level and 
therefore did not provide additional information about the possibility 
of response.
    Data suggest that beyond a certain distance, significant behavioral 
responses are unlikely. At shorter ranges (less than 10 km) some 
behavioral responses have been observed at received levels below 140 dB 
re 1 [mu]Pa. Thus, proximity may mediate behavioral responses at lower 
received levels. Since most data used to derive the BRFs are within 10 
km of the source, probability of response at farther ranges is not 
well-represented. Therefore, the source-receiver range must be 
considered separately to estimate likely significant behavioral 
responses.
    This analysis applies behavioral cut-off conditions to responses 
predicted using the BRFs. Animals within a specified distance and above 
a minimum probability of response are assumed to have a significant 
behavioral response. The cut-off distance is based on the farthest 
source-animal distance across all known studies where animals exhibited 
a significant behavioral response. Animals beyond the cut-off distance 
but with received levels above the sound pressure level associated with 
a probability of response of 0.50 on the BRF are also assumed to have a 
significant behavioral response. The actual likelihood of significant 
behavioral responses occurring beyond the distance cut-off is unknown. 
Significant behavioral responses beyond 100 km are unlikely based on 
source-animal distance and attenuated received levels. The behavioral 
cut-off conditions and additional information on the derivation of the 
cut-off conditions can be found in table 2.2-3 of the ``Criteria and 
Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase 
4)'' technical report (U.S. Department of the Navy, 2024).
    The Action Proponents used cutoff distances beyond which the 
potential of significant behavioral responses (and therefore Level B 
harassment) is considered to be unlikely (see table 20). These 
distances were determined by examining all available published field 
observations of behavioral responses to sonar or sonar-like signals 
that included the distance between the sound source and the marine 
mammal. Behavioral effects calculations are based on the maximum SPL to 
which a modeled marine mammal is exposed. There is empirical evidence 
to suggest that animals are more likely to exhibit significant 
behavioral responses to moderate levels sounds that are closer and less 
likely to exhibit behavioral responses when exposed to moderate levels 
of sound from a source that is far away. To account for this, the 
Action Proponents have implemented behavioral cutoffs that consider 
both received sound level and distance from the source. These updated 
cutoffs conditions are unique to each behavioral hearing group, and are 
outlined in table 20.

   Table 20--Behavioral Cut-Off Conditions for Each Behavioral Hearing
                                  Group
------------------------------------------------------------------------
                                  Received level
                                 associated with
                                  p(0.50) on the
       Behavioral group             behavioral      Cut-off range  (km)
                                response function
                                     (dB rms)
------------------------------------------------------------------------
Sensitive Species.............  133..............  40
Odontocetes...................  168..............  15
Mysticetes....................  185..............  10
Pinnipeds.....................  156..............  5
------------------------------------------------------------------------
Note: Sensitive Species includes beaked whales and harbor porpoises.


[[Page 19954]]

    The Action Proponents and NMFS have used the best available science 
to address the challenging differentiation between significant and non-
significant behavioral responses (i.e., whether the behavior has been 
abandoned or significantly altered such that it qualifies as 
harassment), but have erred on the cautious side where uncertainty 
exists (e.g., counting these lower duration responses as take), which 
likely results in some degree of overestimation of Level B harassment 
by behavioral disturbance. We consider application of these behavioral 
harassment thresholds, therefore, as identifying the maximum number of 
instances in which marine mammals could be reasonably expected to 
experience a disruption in behavior patterns to a point where they are 
abandoned or significantly altered (i.e., Level B harassment). NMFS has 
carefully reviewed the criteria (i.e., BRFs and cutoff distances for 
the species), and agrees that it is the best available science and is 
the appropriate method to use at this time for determining impacts to 
marine mammals from military sonar and other transducers and for 
calculating take and to support the determinations made in this 
proposed rule. Because this is the most appropriate method for 
estimating Level B harassment given the best available science and 
uncertainty on the topic, it is these numbers of Level B harassment by 
behavioral disturbance that are analyzed in the Preliminary Analysis 
and Negligible Impact Determination section and would be authorized.
Air Guns, Pile Driving, and Explosives--
    Based on what the available science indicates and the practical 
need to use a threshold based on a factor that is both predictable and 
measurable for most activities, NMFS uses generalized acoustic 
thresholds based on received level to estimate the onset of behavioral 
harassment for sources other than active sonar. NMFS predicts that 
marine mammals are likely to be behaviorally harassed in a manner we 
consider Level B harassment when exposed to underwater anthropogenic 
noise above received levels of 120 dB re 1 [mu]Pa (rms) for continuous 
(e.g., vibratory pile-driving, drilling) and above 160 dB re 1 [mu]Pa 
(rms) for non-explosive impulsive (e.g., seismic air guns) or 
intermittent (e.g., scientific sonar) sources. For the Action 
Proponents' activities, to estimate behavioral effects from air guns, 
the threshold of 160 dB re 1 [micro]Pa (rms) is used and the root mean 
square calculation for air guns is based on the duration defined by 90 
percent of the cumulative energy in the impulse. The indicated 
thresholds were also applied to estimate behavioral effects from impact 
and vibratory pile driving (table 21). These thresholds are the same as 
those applied in the prior analysis (Phase III) of these stressors in 
the Study Area, although the explosive behavioral threshold has 
shifted, corresponding to changes in the TTS thresholds.

 Table 21--Behavioral Response Thresholds for Air Gun, Pile Driving, and
                               Explosives
------------------------------------------------------------------------
           Sound source                     Behavioral threshold
------------------------------------------------------------------------
Air gun...........................  160 dB rms re 1 [mu]Pa SPL.
Impact pile driving...............  160 dB rms re 1 [mu]Pa SPL.
Vibratory pile driving............  120 dB rms re 1 [mu]Pa SPL.
Single explosion..................  TTS onset threshold (weighted SEL).
Multiple explosions...............  5 dB less than the TTS onset
                                     threshold (weighted SEL).
------------------------------------------------------------------------

    While the best available science for assessing behavioral responses 
of marine mammals to impulsive sounds relies on data from seismic and 
pile driving sources, it is likely that these predicted responses using 
a threshold based on seismic and pile driving represent a worst-case 
scenario compared to behavioral responses to explosives used in 
military readiness activities, which would typically consist of single 
impulses or a cluster of impulses rather than long-duration, repeated 
impulses (e.g., large-scale air gun arrays).
    For single explosions at received sound levels below hearing loss 
thresholds, the most likely behavioral response is a brief alerting or 
orienting response. Since no further sounds follow the initial brief 
impulses, significant behavioral responses would not be expected to 
occur. If a significant response were to occur, the Action Proponents' 
analysis assumes it would be as a result of an exposure at levels 
within the range of auditory impacts (TTS and AUD INJ). Because of this 
approach, the number of auditory impacts is higher than the number of 
behavioral impacts in the quantified results for some stocks.
    If more than one explosive event occurs within any given 24-hour 
period during a military readiness activity, behavioral disturbance is 
considered more likely to occur and specific criteria are applied to 
predict the number of animals that may have a behavioral response. For 
events with multiple explosions, the behavioral threshold used in this 
analysis is 5 dB less than the TTS onset threshold. This value is 
derived from observed onsets of behavioral response by test subjects 
(bottlenose dolphins) during non-impulse TTS testing (Schlundt et al., 
2000).

Navy Acoustic Effects Model

    The Navy Acoustic Effects Model (NAEMO) is their standard model for 
assessing acoustic effects on marine mammals. NAEMO calculates sound 
energy propagation from sonar and other transducers, air guns, and 
explosives during military readiness activities and the sound received 
by animat dosimeters. Animat dosimeters are virtual representations of 
marine mammals distributed in the area around the modeled activity and 
each dosimeter records its individual sound ``dose.'' The model bases 
the distribution of animats over the AFTT Study Area on the density 
values in the Navy Marine Species Density Database (NMSDD) and 
distributes animats in the water column proportional to the known time 
that species spend at varying depths.
    The model accounts for environmental variability of sound 
propagation in both distance and depth when computing the sound level 
received by the animats. The model conducts a statistical analysis 
based on multiple model runs to compute the estimated effects on 
animals. The number of animats that exceed the thresholds for effects 
is tallied to provide an estimate of the number of marine mammals that 
could be affected.
    Assumptions in NAEMO intentionally err on the side of 
overestimation when there are unknowns. The specified activities are 
modeled as though they would occur regardless of proximity to marine 
mammals, meaning that the implementation of power downs or shut downs 
are not modeled or, thereby,

[[Page 19955]]

considered in the take estimates. For more information on this process, 
see the discussion in the Estimated Take from Acoustic Stressors 
section below. Many explosions from ordnance such as bombs and missiles 
actually occur upon impact with above-water targets. However, for this 
analysis, sources such as these were modeled as exploding underwater. 
This overestimates the amount of explosive and acoustic energy entering 
the water.
    The model estimates the acoustic impacts caused by sonars and other 
transducers, explosives, and air guns during individual military 
readiness exercises. During any individual modeled event, impacts to 
individual animats are considered over 24-hour periods. The animats do 
not represent actual animals, but rather they represent a distribution 
of animals based on density and abundance data, which allows for a 
statistical analysis of the number of instances that marine mammals may 
be exposed to sound levels resulting in an effect. Therefore, the model 
estimates the number of instances in which an effect threshold was 
exceeded over the course of a year, but does not estimate the number of 
individual marine mammals that may be impacted over a year (i.e., some 
marine mammals could be impacted several times, while others would not 
experience any impact). A detailed explanation of the Navy's Acoustic 
Effects Model is provided in the technical report ``Quantifying 
Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and 
Analytical Approach for Phase IV Training and Testing'' (U.S. 
Department of the Navy, 2024).
    As NAEMO interrogates the simulation data in the Animat Processor, 
exposures that are both outside the distance cutoff and below the 
received level cutoff are omitted when determining the maximum SPL for 
each animat. This differs from Phase III, in which only distance 
cutoffs were applied, meaning that all exposures outside the distance 
cutoffs were omitted, with no consideration of received level.
    The presence of the two cutoff criteria in Phase IV provides a more 
accurate and conservative estimation of behavioral effects because 
louder exposures that would have been omitted previously, when only a 
distance cutoff was applied, are considered in Phase IV, while the 
estimation of behavioral effects still omits exposures at distances and 
received levels that would be unlikely to produce a significant 
behavioral response. NAEMO retains the capability of calculating 
behavioral effects without the cutoffs applied, depending on user 
preference.
    The impulsive behavioral criteria are not based on the probability 
of a behavioral response but rather on a single SPL metric. For 
consideration of impulsive behavioral effects, the cutoff conditions in 
table 20 are not applied.

Pile Driving

    The Action Proponents performed a quantitative analysis without 
NAEMO to estimate the number of times marine mammals could be affected 
by pile driving and extraction used during proposed training 
activities. The analysis considered details of the activity, sound 
exposure criteria, and the number and distribution of marine mammals. 
This information was then used in an ``area*density'' model in which 
the areas within each footprint (i.e., harassment zone) that 
encompassed a potential effect were calculated for a given day's 
activities. The effects analyzed included behavioral response, TTS, and 
AUD INJ for marine mammals.
    Then, these areas were multiplied by the density of each marine 
species within the nearshore environment to estimate the number of 
effects. Uniform density values for species expected to be present in 
the nearshore areas where pile driving could occur were estimated using 
the NMSDD or available survey data specific to the activity location. 
More detail is provided in the 2024 AFTT Draft Supplemental EIS/OEIS. 
Since the same animal can be ``taken'' every day (i.e., 24-hour reset 
time), the number of predicted effects from a given day were multiplied 
by the number of days for that activity. This generated a total 
estimated number of effects over the entire activity, which was then 
multiplied by the maximum number of times per year this activity could 
happen. The result was the estimated effects per species and stock in a 
year.

Range to Effects

    This section provides range (distance) to effects for sonar and 
other active acoustic sources as well as explosives to specific 
acoustic thresholds determined using NAEMO. Ranges are determined by 
modeling the distance that noise from a source will need to propagate 
to reach exposure level thresholds specific to a hearing group that 
will cause behavioral response, TTS, AUD INJ, non-auditory injury, and 
mortality. Ranges to effects (tables 22 through 42) are utilized to 
help predict impacts from acoustic and explosive sources and assess the 
benefit of mitigation zones. Marine mammals exposed within these ranges 
for the shown duration are predicted to experience the associated 
effect. Range to effects is important information in not only 
predicting acoustic impacts, but also in verifying the accuracy of 
model results against real-world situations and determining adequate 
mitigation ranges to avoid higher level effects, especially 
physiological effects to marine mammals.

Sonar

    Ranges to effects for sonar were determined by modeling the 
distance that sound would need to propagate to reach exposure level 
thresholds specific to a hearing group that would cause behavioral 
response, TTS, and AUD INJ, as described in the ``Criteria and 
Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase 
4)'' technical report (U.S. Department of the Navy, 2024). The ranges 
do not account for an animal avoiding a source nor for the movement of 
the platform, both of which would influence the actual range to onset 
of auditory effects during an actual exposure.
    Table 22 through table 26 below provide the ranges to TTS and AUD 
INJ for marine mammals from exposure durations of 1, 30, 60, and 120 
seconds for six sonar systems proposed for use (see also appendix A of 
the application). Due to the lower acoustic thresholds for TTS versus 
AUD INJ, ranges to TTS are larger. Successive pings can be expected to 
add together, further increasing the range to the onset of TTS and AUD 
INJ.

                        Table 22--Very Low-Frequency Cetacean Ranges to Effects for Sonar
----------------------------------------------------------------------------------------------------------------
                                             Duration
         Sonar type            Depth (m)       (s)              Range to TTS               Range to AUD INJ
----------------------------------------------------------------------------------------------------------------
Dipping Sonar...............        <=200            1  160 m (34 m)...............  12 m (6 m).
Dipping Sonar...............        <=200           30  330 m (70 m)...............  21 m (10 m).
Dipping Sonar...............        <=200           60  460 m (98 m)...............  25 m (10 m).
Dipping Sonar...............        <=200          120  700 m (145 m)..............  35 m (8 m).

[[Page 19956]]

 
Dipping Sonar...............         >200            1  140 m (42 m)...............  0 m (1 m).
Dipping Sonar...............         >200           30  250 m (81 m)...............  0 m (8 m).
Dipping Sonar...............         >200           60  330 m (115 m)..............  18 m (11 m).
Dipping Sonar...............         >200          120  499 m (172 m)..............  35 m (15 m).
MF1 Ship Sonar..............        <=200            1  1,528 m (635 m)............  90 m (10 m).
MF1 Ship Sonar..............        <=200           30  1,528 m (635 m)............  90 m (10 m).
MF1 Ship Sonar..............        <=200           60  2,514 m (1,176 m)..........  140 m (19 m).
MF1 Ship Sonar..............        <=200          120  3,264 m (1,592 m)..........  180 m (27 m).
MF1 Ship Sonar..............         >200            1  1,000 m (449 m)............  85 m (3 m).
MF1 Ship Sonar..............         >200           30  1,000 m (449 m)............  85 m (3 m).
MF1 Ship Sonar..............         >200           60  1,750 m (804 m)............  130 m (6 m).
MF1 Ship Sonar..............         >200          120  2,250 m (1,143 m)..........  170 m (9 m).
MF1C Ship Sonar.............        <=200            1  1,542 m (637 m)............  90 m (10 m).
MF1C Ship Sonar.............        <=200           30  3,306 m (1,596 m)..........  180 m (27 m).
MF1C Ship Sonar.............        <=200           60  4,917 m (2,648 m)..........  273 m (51 m).
MF1C Ship Sonar.............        <=200          120  6,944 m (4,219 m)..........  447 m (92 m).
MF1C Ship Sonar.............         >200            1  1,000 m (460 m)............  85 m (3 m).
MF1C Ship Sonar.............         >200           30  2,250 m (1,162 m)..........  170 m (9 m).
MF1C Ship Sonar.............         >200           60  4,278 m (1,747 m)..........  250 m (15 m).
MF1C Ship Sonar.............         >200          120  5,750 m (2,558 m)..........  370 m (37 m).
MF1K Ship Sonar.............        <=200            1  200 m (27 m)...............  13 m (2 m).
MF1K Ship Sonar.............        <=200           30  412 m (77 m)...............  24 m (1 m).
MF1K Ship Sonar.............        <=200           60  575 m (106 m)..............  30 m (1 m).
MF1K Ship Sonar.............        <=200          120  885 m (191 m)..............  45 m (3 m).
MF1K Ship Sonar.............         >200            1  190 m (7 m)................  11 m (6 m).
MF1K Ship Sonar.............         >200           30  340 m (18 m)...............  23 m (11 m).
MF1K Ship Sonar.............         >200           60  440 m (31 m)...............  30 m (2 m).
MF1K Ship Sonar.............         >200          120  625 m (58 m)...............  40 m (2 m).
Mine-Hunting Sonar..........        <=200            1  3 m (2 m)..................  0 m (0 m).
Mine-Hunting Sonar..........        <=200           30  6 m (3 m)..................  0 m (0 m).
Mine-Hunting Sonar..........        <=200           60  9 m (5 m)..................  0 m (0 m).
Mine-Hunting Sonar..........        <=200          120  13 m (7 m).................  1 m (0 m).
Mine-Hunting Sonar..........         >200            1  0 m (0 m)..................  0 m (0 m).
Mine-Hunting Sonar..........         >200           30  5 m (2 m)..................  0 m (0 m).
Mine-Hunting Sonar..........         >200           60  8 m (4 m)..................  0 m (0 m).
Mine-Hunting Sonar..........         >200          120  12 m (6 m).................  0 m (0 m).
Sonobuoy Sonar..............        <=200            1  13 m (7 m).................  0 m (0 m).
Sonobuoy Sonar..............        <=200           30  25 m (11 m)................  0 m (0 m).
Sonobuoy Sonar..............        <=200           60  35 m (15 m)................  0 m (1 m).
Sonobuoy Sonar..............        <=200          120  50 m (16 m)................  0 m (2 m).
Sonobuoy Sonar..............         >200            1  0 m (7 m)..................  0 m (0 m).
Sonobuoy Sonar..............         >200           30  23 m (12 m)................  0 m (0 m).
Sonobuoy Sonar..............         >200           60  35 m (17 m)................  0 m (0 m).
Sonobuoy Sonar..............         >200          120  50 m (20 m)................  0 m (0 m).
----------------------------------------------------------------------------------------------------------------
Note: Median ranges are shown with standard deviation ranges in parentheses. The Action Proponents split the LF
  functional hearing group into LF and VLF based on Houser et al., (2024), however, NMFS updated acoustic
  technical guidance (NMFS, 2024) does not include these data but we have included the VLF group here for
  reference.


                          Table 23--Low-Frequency Cetacean Ranges to Effects for Sonar
----------------------------------------------------------------------------------------------------------------
                                             Duration
         Sonar type            Depth (m)       (s)              Range to TTS               Range to AUD INJ
----------------------------------------------------------------------------------------------------------------
Dipping Sonar...............        <=200            1  166 m (63 m)...............  12 m (5 m).
Dipping Sonar...............        <=200           30  333 m (109 m)..............  21 m (7 m).
Dipping Sonar...............        <=200           60  465 m (138 m)..............  25 m (8 m).
Dipping Sonar...............        <=200          120  701 m (154 m)..............  35 m (12 m).
Dipping Sonar...............         >200            1  140 m (78 m)...............  0 m (6 m).
Dipping Sonar...............         >200           30  220 m (120 m)..............  13 m (10 m).
Dipping Sonar...............         >200           60  280 m (156 m)..............  24 m (12 m).
Dipping Sonar...............         >200          120  440 m (110 m)..............  35 m (18 m).
MF1 Ship Sonar..............        <=200            1  1,653 m (658 m)............  95 m (10 m).
MF1 Ship Sonar..............        <=200           30  1,653 m (658 m)............  95 m (10 m).
MF1 Ship Sonar..............        <=200           60  2,653 m (1,213 m)..........  140 m (20 m).
MF1 Ship Sonar..............        <=200          120  3,486 m (1,632 m)..........  180 m (27 m).
MF1 Ship Sonar..............         >200            1  1,042 m (498 m)............  90 m (4 m).
MF1 Ship Sonar..............         >200           30  1,042 m (498 m)............  90 m (4 m).
MF1 Ship Sonar..............         >200           60  1,819 m (863 m)............  140 m (5 m).
MF1 Ship Sonar..............         >200          120  2,694 m (1,210 m)..........  180 m (8 m).
MF1C Ship Sonar.............        <=200            1  1,653 m (660 m)............  93 m (10 m).

[[Page 19957]]

 
MF1C Ship Sonar.............        <=200           30  3,528 m (1,637 m)..........  180 m (27 m).
MF1C Ship Sonar.............        <=200           60  5,208 m (2,724 m)..........  286 m (52 m).
MF1C Ship Sonar.............        <=200          120  7,458 m (4,345 m)..........  461 m (95 m).
MF1C Ship Sonar.............         >200            1  1,056 m (511 m)............  90 m (4 m).
MF1C Ship Sonar.............         >200           30  2,708 m (1,231 m)..........  180 m (8 m).
MF1C Ship Sonar.............         >200           60  4,514 m (1,834 m)..........  260 m (16 m).
MF1C Ship Sonar.............         >200          120  6,167 m (2,656 m)..........  380 m (41 m).
MF1K Ship Sonar.............        <=200            1  200 m (28 m)...............  14 m (1 m).
MF1K Ship Sonar.............        <=200           30  429 m (80 m)...............  25 m (0 m).
MF1K Ship Sonar.............        <=200           60  596 m (112 m)..............  30 m (1 m).
MF1K Ship Sonar.............        <=200          120  915 m (203 m)..............  45 m (3 m).
MF1K Ship Sonar.............         >200            1  190 m (6 m)................  14 m (1 m).
MF1K Ship Sonar.............         >200           30  350 m (14 m)...............  24 m (1 m).
MF1K Ship Sonar.............         >200           60  450 m (33 m)...............  30 m (0 m).
MF1K Ship Sonar.............         >200          120  650 m (72 m)...............  45 m (0 m).
Mine-Hunting Sonar..........        <=200            1  9 m (5 m)..................  0 m (0 m).
Mine-Hunting Sonar..........        <=200           30  18 m (9 m).................  1 m (1 m).
Mine-Hunting Sonar..........        <=200           60  25 m (11 m)................  2 m (1 m).
Mine-Hunting Sonar..........        <=200          120  35 m (14 m)................  3 m (2 m).
Mine-Hunting Sonar..........         >200            1  8 m (4 m)..................  0 m (0 m).
Mine-Hunting Sonar..........         >200           30  17 m (8 m).................  1 m (0 m).
Mine-Hunting Sonar..........         >200           60  25 m (11 m)................  2 m (1 m).
Mine-Hunting Sonar..........         >200          120  35 m (10 m)................  3 m (1 m).
Sonobuoy Sonar..............        <=200            1  12 m (8 m).................  0 m (0 m).
Sonobuoy Sonar..............        <=200           30  25 m (11 m)................  0 m (0 m).
Sonobuoy Sonar..............        <=200           60  40 m (16 m)................  0 m (1 m).
Sonobuoy Sonar..............        <=200          120  55 m (23 m)................  0 m (1 m).
Sonobuoy Sonar..............         >200            1  0 m (7 m)..................  0 m (0 m).
Sonobuoy Sonar..............         >200           30  20 m (12 m)................  0 m (0 m).
Sonobuoy Sonar..............         >200           60  35 m (19 m)................  0 m (0 m).
Sonobuoy Sonar..............         >200          120  55 m (27 m)................  0 m (0 m).
----------------------------------------------------------------------------------------------------------------
Note: Median ranges are shown with standard deviation ranges in parentheses. The Action Proponents split the LF
  functional hearing group into LF and VLF based on Houser et al., (2024), however, NMFS updated acoustic
  technical guidance (NMFS, 2024) does not include these data but we have included the VLF group here for
  reference.


                          Table 24--High-Frequency Cetacean Ranges to Effects for Sonar
----------------------------------------------------------------------------------------------------------------
                                             Duration
         Sonar type            Depth (m)       (s)              Range to TTS               Range to AUD INJ
----------------------------------------------------------------------------------------------------------------
Dipping Sonar...............        <=200            1  55 m (18 m)................  5 m (2 m).
Dipping Sonar...............        <=200           30  120 m (42 m)...............  9 m (3 m).
Dipping Sonar...............        <=200           60  170 m (60 m)...............  12 m (5 m).
Dipping Sonar...............        <=200          120  270 m (90 m)...............  18 m (6 m).
Dipping Sonar...............         >200            1  50 m (27 m)................  0 m (2 m).
Dipping Sonar...............         >200           30  100 m (56 m)...............  0 m (4 m).
Dipping Sonar...............         >200           60  140 m (77 m)...............  0 m (6 m).
Dipping Sonar...............         >200          120  209 m (113 m)..............  0 m (8 m).
MF1 Ship Sonar..............        <=200            1  832 m (189 m)..............  45 m (3 m).
MF1 Ship Sonar..............        <=200           30  832 m (189 m)..............  45 m (3 m).
MF1 Ship Sonar..............        <=200           60  1,208 m (357 m)............  65 m (6 m).
MF1 Ship Sonar..............        <=200          120  1,500 m (561 m)............  85 m (9 m).
MF1 Ship Sonar..............         >200            1  600 m (117 m)..............  45 m (11 m).
MF1 Ship Sonar..............         >200           30  600 m (117 m)..............  45 m (11 m).
MF1 Ship Sonar..............         >200           60  892 m (263 m)..............  65 m (13 m).
MF1 Ship Sonar..............         >200          120  1,000 m (421 m)............  85 m (6 m).
MF1C Ship Sonar.............        <=200            1  835 m (189 m)..............  45 m (3 m).
MF1C Ship Sonar.............        <=200           30  1,500 m (562 m)............  85 m (9 m).
MF1C Ship Sonar.............        <=200           60  2,514 m (1,075 m)..........  130 m (17 m).
MF1C Ship Sonar.............        <=200          120  4,069 m (1,805 m)..........  200 m (30 m).
MF1C Ship Sonar.............         >200            1  600 m (120 m)..............  45 m (11 m).
MF1C Ship Sonar.............         >200           30  1,000 m (432 m)............  85 m (6 m).
MF1C Ship Sonar.............         >200           60  1,736 m (783 m)............  130 m (8 m).
MF1C Ship Sonar.............         >200          120  3,028 m (1,363 m)..........  200 m (12 m).
MF1K Ship Sonar.............        <=200            1  100 m (9 m)................  7 m (3 m).
MF1K Ship Sonar.............        <=200           30  190 m (25 m)...............  13 m (3 m).
MF1K Ship Sonar.............        <=200           60  270 m (42 m)...............  17 m (3 m).
MF1K Ship Sonar.............        <=200          120  430 m (80 m)...............  25 m (1 m).
MF1K Ship Sonar.............         >200            1  100 m (19 m)...............  7 m (3 m).
MF1K Ship Sonar.............         >200           30  180 m (11 m)...............  13 m (6 m).

[[Page 19958]]

 
MF1K Ship Sonar.............         >200           60  240 m (11 m)...............  17 m (7 m).
MF1K Ship Sonar.............         >200          120  350 m (18 m)...............  25 m (9 m).
Mine-Hunting Sonar..........        <=200            1  8 m (4 m)..................  0 m (0 m).
Mine-Hunting Sonar..........        <=200           30  15 m (6 m).................  1 m (0 m).
Mine-Hunting Sonar..........        <=200           60  22 m (8 m).................  1 m (1 m).
Mine-Hunting Sonar..........        <=200          120  30 m (9 m).................  2 m (1 m).
Mine-Hunting Sonar..........         >200            1  7 m (3 m)..................  0 m (0 m).
Mine-Hunting Sonar..........         >200           30  15 m (5 m).................  0 m (0 m).
Mine-Hunting Sonar..........         >200           60  21 m (7 m).................  0 m (1 m).
Mine-Hunting Sonar..........         >200          120  25 m (6 m).................  0 m (1 m).
Sonobuoy Sonar..............        <=200            1  8 m (4 m)..................  0 m (0 m).
Sonobuoy Sonar..............        <=200           30  18 m (8 m).................  0 m (0 m).
Sonobuoy Sonar..............        <=200           60  25 m (12 m)................  0 m (0 m).
Sonobuoy Sonar..............        <=200          120  35 m (13 m)................  0 m (1 m).
Sonobuoy Sonar..............         >200            1  0 m (4 m)..................  0 m (0 m).
Sonobuoy Sonar..............         >200           30  0 m (9 m)..................  0 m (0 m).
Sonobuoy Sonar..............         >200           60  0 m (12 m).................  0 m (0 m).
Sonobuoy Sonar..............         >200          120  25 m (16 m)................  0 m (1 m).
----------------------------------------------------------------------------------------------------------------
Note: Median ranges are shown with standard deviation ranges in parentheses.


                       Table 25--Very High-Frequency Cetacean Ranges to Effects for Sonar
----------------------------------------------------------------------------------------------------------------
                                             Duration
         Sonar type            Depth (m)       (s)              Range to TTS               Range to AUD INJ
----------------------------------------------------------------------------------------------------------------
Dipping Sonar...............        <=200            1  100 m (37 m)...............  8 m (3 m).
Dipping Sonar...............        <=200           30  210 m (79 m)...............  14 m (5 m).
Dipping Sonar...............        <=200           60  291 m (97 m)...............  19 m (6 m).
Dipping Sonar...............        <=200          120  454 m (104 m)..............  25 m (8 m).
Dipping Sonar...............         >200            1  95 m (49 m)................  0 m (3 m).
Dipping Sonar...............         >200           30  180 m (98 m)...............  0 m (6 m).
Dipping Sonar...............         >200           60  230 m (125 m)..............  14 m (8 m).
Dipping Sonar...............         >200          120  310 m (75 m)...............  24 m (12 m).
MF1 Ship Sonar..............        <=200            1  2,750 m (1,203 m)..........  150 m (19 m).
MF1 Ship Sonar..............        <=200           30  2,750 m (1,203 m)..........  150 m (19 m).
MF1 Ship Sonar..............        <=200           60  4,347 m (2,022 m)..........  230 m (36 m).
MF1 Ship Sonar..............        <=200          120  5,306 m (2,709 m)..........  293 m (51 m).
MF1 Ship Sonar..............         >200            1  1,806 m (867 m)............  150 m (6 m).
MF1 Ship Sonar..............         >200           30  1,806 m (867 m)............  150 m (6 m).
MF1 Ship Sonar..............         >200           60  3,569 m (1,420 m)..........  220 m (12 m).
MF1 Ship Sonar..............         >200          120  4,500 m (1,761 m)..........  270 m (15 m).
MF1C Ship Sonar.............        <=200            1  2,778 m (1,206 m)..........  150 m (19 m).
MF1C Ship Sonar.............        <=200           30  5,472 m (2,717 m)..........  295 m (51 m).
MF1C Ship Sonar.............        <=200           60  7,861 m (4,337 m)..........  480 m (94 m).
MF1C Ship Sonar.............        <=200          120  10,896 m (6,387 m).........  750 m (163 m).
MF1C Ship Sonar.............         >200            1  1,806 m (892 m)............  150 m (6 m).
MF1C Ship Sonar.............         >200           30  4,514 m (1,802 m)..........  270 m (16 m).
MF1C Ship Sonar.............         >200           60  6,139 m (2,607 m)..........  390 m (42 m).
MF1C Ship Sonar.............         >200          120  8,403 m (3,750 m)..........  550 m (95 m).
MF1K Ship Sonar.............        <=200            1  350 m (61 m)...............  20 m (1 m).
MF1K Ship Sonar.............        <=200           30  724 m (139 m)..............  35 m (1 m).
MF1K Ship Sonar.............        <=200           60  976 m (222 m)..............  50 m (3 m).
MF1K Ship Sonar.............        <=200          120  1,306 m (456 m)............  85 m (6 m).
MF1K Ship Sonar.............         >200            1  300 m (9 m)................  16 m (3 m).
MF1K Ship Sonar.............         >200           30  525 m (46 m)...............  35 m (0 m).
MF1K Ship Sonar.............         >200           60  700 m (78 m)...............  50 m (2 m).
MF1K Ship Sonar.............         >200          120  1,000 m (138 m)............  85 m (3 m).
Mine-Hunting Sonar..........        <=200            1  130 m (54 m)...............  9 m (1 m).
Mine-Hunting Sonar..........        <=200           30  291 m (115 m)..............  16 m (2 m).
Mine-Hunting Sonar..........        <=200           60  453 m (161 m)..............  24 m (3 m).
Mine-Hunting Sonar..........        <=200          120  653 m (198 m)..............  35 m (6 m).
Mine-Hunting Sonar..........         >200            1  90 m (6 m).................  8 m (1 m).
Mine-Hunting Sonar..........         >200           30  150 m (15 m)...............  15 m (0 m).
Mine-Hunting Sonar..........         >200           60  210 m (30 m)...............  22 m (0 m).
Mine-Hunting Sonar..........         >200          120  300 m (45 m)...............  30 m (0 m).
Sonobuoy Sonar..............        <=200            1  65 m (22 m)................  0 m (3 m).
Sonobuoy Sonar..............        <=200           30  140 m (67 m)...............  9 m (4 m).
Sonobuoy Sonar..............        <=200           60  218 m (98 m)...............  15 m (5 m).
Sonobuoy Sonar..............        <=200          120  349 m (128 m)..............  22 m (7 m).
Sonobuoy Sonar..............         >200            1  65 m (31 m)................  0 m (1 m).

[[Page 19959]]

 
Sonobuoy Sonar..............         >200           30  110 m (60 m)...............  0 m (5 m).
Sonobuoy Sonar..............         >200           60  180 m (87 m)...............  10 m (6 m).
Sonobuoy Sonar..............         >200          120  280 m (72 m)...............  21 m (10 m).
----------------------------------------------------------------------------------------------------------------
Note: Median ranges are shown with standard deviation ranges in parentheses.


                         Table 26--Phocid Carnivore in Water Ranges to Effects for Sonar
----------------------------------------------------------------------------------------------------------------
                                             Duration
         Sonar type            Depth (m)       (s)              Range to TTS               Range to AUD INJ
----------------------------------------------------------------------------------------------------------------
Dipping Sonar...............        <=200            1  208 m (63 m)...............  0 m (7 m).
Dipping Sonar...............        <=200           30  410 m (87 m)...............  22 m (8 m).
Dipping Sonar...............        <=200           60  564 m (117 m)..............  30 m (10 m).
Dipping Sonar...............        <=200          120  853 m (170 m)..............  45 m (15 m).
Dipping Sonar...............         >200            1  170 m (80 m)...............  0 m (6 m).
Dipping Sonar...............         >200           30  300 m (73 m)...............  0 m (11 m).
Dipping Sonar...............         >200           60  400 m (84 m)...............  0 m (14 m).
Dipping Sonar...............         >200          120  600 m (131 m)..............  35 m (21 m).
MF1 Ship Sonar..............        <=200            1  2,181 m (982 m)............  120 m (16 m).
MF1 Ship Sonar..............        <=200           30  2,181 m (982 m)............  120 m (16 m).
MF1 Ship Sonar..............        <=200           60  3,417 m (1,671 m)..........  186 m (28 m).
MF1 Ship Sonar..............        <=200          120  4,306 m (2,258 m)..........  240 m (41 m).
MF1 Ship Sonar..............         >200            1  1,500 m (708 m)............  120 m (5 m).
MF1 Ship Sonar..............         >200           30  1,500 m (708 m)............  120 m (5 m).
MF1 Ship Sonar..............         >200           60  2,667 m (1,231 m)..........  180 m (9 m).
MF1 Ship Sonar..............         >200          120  3,819 m (1,543 m)..........  230 m (13 m).
MF1C Ship Sonar.............        <=200            1  2,181 m (982 m)............  120 m (16 m).
MF1C Ship Sonar.............        <=200           30  4,333 m (2,258 m)..........  240 m (41 m).
MF1C Ship Sonar.............        <=200           60  6,194 m (3,650 m)..........  381 m (77 m).
MF1C Ship Sonar.............        <=200          120  8,556 m (5,510 m)..........  606 m (130 m).
MF1C Ship Sonar.............         >200            1  1,500 m (708 m)............  120 m (5 m).
MF1C Ship Sonar.............         >200           30  3,819 m (1,543 m)..........  230 m (13 m).
MF1C Ship Sonar.............         >200           60  5,264 m (2,269 m)..........  330 m (28 m).
MF1C Ship Sonar.............         >200          120  7,292 m (3,235 m)..........  480 m (59 m).
MF1K Ship Sonar.............        <=200            1  270 m (43 m)...............  17 m (6 m).
MF1K Ship Sonar.............        <=200           30  557 m (104 m)..............  30 m (4 m).
MF1K Ship Sonar.............        <=200           60  775 m (155 m)..............  40 m (3 m).
MF1K Ship Sonar.............        <=200          120  1,000 m (312 m)............  65 m (5 m).
MF1K Ship Sonar.............         >200            1  240 m (8 m)................  16 m (6 m).
MF1K Ship Sonar.............         >200           30  430 m (27 m)...............  30 m (11 m).
MF1K Ship Sonar.............         >200           60  550 m (47 m)...............  35 m (14 m).
MF1K Ship Sonar.............         >200          120  800 m (98 m)...............  60 m (3 m).
Mine-Hunting Sonar..........        <=200            1  15 m (5 m).................  0 m (0 m).
Mine-Hunting Sonar..........        <=200           30  25 m (6 m).................  0 m (1 m).
Mine-Hunting Sonar..........        <=200           60  40 m (8 m).................  0 m (2 m).
Mine-Hunting Sonar..........        <=200          120  65 m (13 m)................  4 m (2 m).
Mine-Hunting Sonar..........         >200            1  14 m (4 m).................  0 m (0 m).
Mine-Hunting Sonar..........         >200           30  25 m (2 m).................  0 m (1 m).
Mine-Hunting Sonar..........         >200           60  35 m (2 m).................  0 m (1 m).
Mine-Hunting Sonar..........         >200          120  50 m (2 m).................  3 m (2 m).
Sonobuoy Sonar..............        <=200            1  21 m (9 m).................  0 m (0 m).
Sonobuoy Sonar..............        <=200           30  35 m (11 m)................  0 m (1 m).
Sonobuoy Sonar..............        <=200           60  50 m (15 m)................  0 m (2 m).
Sonobuoy Sonar..............        <=200          120  75 m (23 m)................  0 m (3 m).
Sonobuoy Sonar..............         >200            1  0 m (10 m).................  0 m (0 m).
Sonobuoy Sonar..............         >200           30  35 m (17 m)................  0 m (1 m).
Sonobuoy Sonar..............         >200           60  50 m (22 m)................  0 m (2 m).
Sonobuoy Sonar..............         >200          120  75 m (33 m)................  0 m (2 m).
----------------------------------------------------------------------------------------------------------------
Note: Median ranges are shown with standard deviation ranges in parentheses.

Air Guns
    Ranges to effects for air guns were determined by modeling the 
distance that sound would need to propagate to reach exposure level 
thresholds specific to a hearing group that would cause behavioral 
response, TTS, and AUD INJ, as described in the ``Criteria and 
Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase 
4)'' report (U.S. Department of the Navy, 2024)). The air gun ranges to 
effects for TTS and AUD INJ in table 27 are based on the metric (i.e., 
SEL or SPL) that produced larger ranges.

[[Page 19960]]



                                                         Table 27--Range to Effects for Air Guns
--------------------------------------------------------------------------------------------------------------------------------------------------------
       Functional hearing group         Depth (m)        Behavioral disturbance                 Range to TTS                    Range to AUD INJ
--------------------------------------------------------------------------------------------------------------------------------------------------------
VLF..................................        <=200  145 m (20 m)....................  27 m (1 m)......................  4 m (1 m).
VLF..................................         >200  143 m (20 m)....................  26 m (1 m)......................  4 m (1 m).
LF...................................        <=200  130 m (18 m)....................  12 m (0 m)......................  2 m (0 m).
LF...................................         >200  130 m (17 m)....................  12 m (0 m)......................  2 m (0 m).
HF...................................        <=200  146 m (20 m)....................  2 m (0 m).......................  1 m (0 m).
HF...................................         >200  145 m (18 m)....................  2 m (0 m).......................  1 m (0 m).
VHF..................................        <=200  150 m (18 m)....................  56 m (3 m)......................  27 m (2 m).
VHF..................................         >200  148 m (16 m)....................  55 m (3 m)......................  27 m (2 m).
PW...................................        <=200  142 m (18 m)....................  5 m (1 m).......................  2 m (0 m).
PW...................................         >200  139 m (17 m)....................  5 m (1 m).......................  2 m (0 m).
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: The values listed for TTS and AUD INJ are the greater of the respective SPL and SEL ranges. Median ranges are shown with standard deviation ranges
  in parentheses. The Action Proponents split the LF functional hearing group into LF and VLF based on Houser et al., (2024), however, NMFS updated
  acoustic technical guidance (NMFS, 2024) does not include these data but we have included the VLF group here for reference.

Pile Driving
    Only two stocks of bottlenose dolphins (Gulf of America Northern 
Coastal stock and Mississippi Sound, Lake Borgne, and Bay Boudreau 
stock) are expected to be present in the nearshore waters of Gulfport, 
Mississippi, where impact and vibratory pile driving and extraction is 
proposed to occur up to four times per year. Table 28 shows the 
predicted ranges to AUD INJ, TTS, and behavioral response for the HF 
hearing group (the only functional hearing group expected in the 
vicinity of pile driving and extraction activities) that were analyzed 
for their exposure to impact and vibratory pile driving. These ranges 
were estimated based on activity parameters described in the Acoustic 
Stressors section of the Explosive and Acoustic Analysis Report (see 
appendix A of the application) and using the calculations described in 
the Quantitative Analysis Technical Report (see ``Quantifying Acoustic 
Impacts on Marine Mammals and Sea Turtles: Methods and Analytical 
Approach for Phase IV Training and Testing'' (U.S. Department of the 
Navy, 2024)).

                    Table 28--Range to Effects for High-Frequency Cetaceans From Pile Driving
----------------------------------------------------------------------------------------------------------------
                                                                    Behavioral
               Pile type                         Method            response (m)       TTS (m)       AUD INJ (m)
----------------------------------------------------------------------------------------------------------------
16-inch timber/plastic................  Impact..................              46              17               2
16-inch timber/plastic................  Vibratory...............           6,310              17               1
24-inch steel sheet...................  Vibratory...............           3,981              11               0
----------------------------------------------------------------------------------------------------------------

Explosives
    The following section provides the range (distance) over which 
specific physiological or behavioral effects are expected to occur 
based on the explosive criteria (see section 6.2.1 (Impacts from 
Explosives) of the application and the ``Criteria and Thresholds for 
U.S. Navy Acoustic and Explosive Effects Analysis (Phase 4)'' report 
(U.S. Department of the Navy, 2024)) and the explosive propagation 
calculations from NAEMO. The range to effects are shown for a range of 
explosive bins, from E1 (0.1-0.25 lb NEW) to E16 (greater than 7,250-
14,500 lb NEW (ship shock trial only)) (table 29 through table 33). 
Ranges are determined by modeling the distance that noise from an 
explosion would need to propagate to reach exposure level thresholds 
specific to a hearing group that would cause behavioral response (to 
the degree of Level B behavioral harassment), TTS, and AUD INJ. NMFS 
has reviewed the range distance to effect data provided by the Action 
Proponents and concurs with the analysis. Range to effects is important 
information in not only predicting impacts from explosives, but also in 
verifying the accuracy of model results against real-world situations 
and determining adequate mitigation ranges to avoid higher level 
effects, especially injury to marine mammals. For additional 
information on how ranges to impacts from explosions were estimated, 
see the technical report ``Quantifying Acoustic Impacts on Marine 
Mammals and Sea Turtles: Methods and Analytical Approach for Phase IV 
Training and Testing'' (U.S. Department of the Navy, 2024).
    Table 29 through table 33 show the minimum, average, and maximum 
ranges to onset of auditory and likely behavioral effects that rise to 
the level of Level B harassment for all functional hearing groups based 
on the developed thresholds. Ranges are provided for a representative 
source depth and cluster size (the number of rounds fired, or buoys 
dropped, within a very short duration) for each bin. Ranges for 
behavioral response are only provided if more than one explosive 
cluster occurs. As noted previously, single explosions at received 
sound levels below TTS and AUD INJ thresholds are most likely to result 
in a brief alerting or orienting response. For events with multiple 
explosions, sound from successive explosions can be expected to 
accumulate and increase the range to the onset of an impact based on 
SEL thresholds. Modeled ranges to TTS and AUD INJ based on peak 
pressure for a single explosion generally exceed the modeled ranges 
based on SEL even when accumulated for multiple explosions. Peak 
pressure-based ranges are estimated using the best available science; 
however, data on peak pressure at far distances from explosions are 
very limited. The explosive ranges to effects for TTS and AUD INJ that 
are in the tables are based on the metric (i.e., SEL or SPL) that 
produced larger ranges.
    Table 34 shows ranges to non-auditory injury and mortality as a

[[Page 19961]]

function of animal mass and explosive bin. For non-auditory injury, the 
larger of the ranges to slight lung injury or gastrointestinal tract 
injury was used as a conservative estimate, and the boxplots in 
appendix A to the application present ranges for both metrics for 
comparison. For the non-auditory metric, ranges are only available for 
a cluster size of one. Animals within water volumes encompassing the 
estimated range to non-auditory injury would be expected to receive 
minor injuries at the outer ranges, increasing to more substantial 
injuries, and finally mortality as an animal approaches the detonation 
point.

                     Table 29--Very Low-Frequency Cetacean Ranges to Effects for Explosives
----------------------------------------------------------------------------------------------------------------
                                                    Range to
       Bin          Depth (m)    Cluster size      behavioral      Range to TTS          Range to AUD INJ
                                                  disturbance
----------------------------------------------------------------------------------------------------------------
E1...............        <=200               1  NA.............  310 m (149 m)..  97 m (6 m).
E1...............        <=200              25  1,250 m (336 m)  800 m (112 m)..  199 m (39 m).
E1...............        <=200             100  5,049 m (2,982   1,604 m (1,238   353 m (74 m).
                                                 m).              m).
E1...............         >200               1  NA.............  305 m (88 m)...  96 m (6 m).
E2...............        <=200               1  NA.............  292 m (9 m)....  98 m (0 m).
E3...............        <=200               1  NA.............  542 m (531 m)..  206 m (22 m).
E3...............        <=200              10  3,569 m (2,949   1,264 m (904 m)  274 m (75 m).
                                                 m).
E3...............         >200               1  NA.............  480 m (275 m)..  208 m (20 m).
E3...............         >200              10  1,500 m (881 m)  925 m (301 m)..  290 m (67 m).
E4...............        <=200               1  NA.............  2,625 m (1,017   378 m (143 m).
                                                                  m).
E4...............         >200               1  NA.............  1,000 m (160 m)  353 m (34 m).
E5...............        <=200               1  NA.............  879 m (1,240 m)  309 m (35 m).
E5...............        <=200               8  11,590 m (7,473  5,375 m (3,258   389 m (119 m).
                                                 m).              m).
E5...............         >200               1  NA.............  650 m (221 m)..  304 m (33 m).
E5...............         >200               8  1,750 m (1,403   1,000 m (654 m)  420 m (92 m).
                                                 m).
E6...............        <=200               1  NA.............  1,472 m (2,322   421 m (56 m).
                                                                  m).
E6...............        <=200               4  16,812 m (4,849  7,131 m (3,505   421 m (56 m).
                                                 m).              m).
E6...............         >200               1  NA.............  743 m (100 m)..  426 m (43 m).
E7...............        <=200               1  NA.............  2,649 m (919 m)  510 m (62 m).
E7...............         >200               1  NA.............  2,989 m (1,004   515 m (66 m).
                                                                  m).
E8...............        <=200               1  NA.............  5,619 m (1,462   767 m (114 m).
                                                                  m).
E8...............         >200               1  NA.............  5,577 m (1,617   781 m (115 m).
                                                                  m).
E9...............        <=200               1  NA.............  6,717 m (3,010   676 m (98 m).
                                                                  m).
E9...............         >200               1  NA.............  6,141 m (2,970   646 m (89 m).
                                                                  m).
E10..............        <=200               1  NA.............  12,778 m (4,320  875 m (153 m).
                                                                  m).
E10..............         >200               1  NA.............  12,964 m (3,612  912 m (158 m).
                                                                  m).
E11..............        <=200               1  NA.............  23,156 m (5,301  3,790 m (770 m).
                                                                  m).
E11..............         >200               1  NA.............  22,108 m (4,622  3,625 m (664 m).
                                                                  m).
E12..............        <=200               1  NA.............  14,652 m (4,177  1,105 m (465 m).
                                                                  m).
E12..............         >200               1  NA.............  16,150 m (3,598  1,093 m (205 m).
                                                                  m).
E16..............         >200               1  NA.............  57,600 m (5,145  16,753 m (2,305 m).
                                                                  m).
----------------------------------------------------------------------------------------------------------------
Note: Behavioral response criteria are applied to explosive clusters >1. The values listed for TTS and AUD INJ
  are the greater of the respective SPL and SEL ranges. Median ranges are shown with standard deviation ranges
  in parentheses. The Action Proponents split the LF functional hearing group into LF and VLF based on Houser et
  al., (2024), however, NMFS updated acoustic technical guidance (NMFS, 2024) does not include these data but we
  have included the VLF group here for reference. E1 (0.1-0.25 lbs), E2 (>0.25-0.5 lbs), E3 (>0.5-2.5 lbs), E4
  (>2.5-5 lbs), E5 (>5-10 lbs), E6 (>10-20 lbs), E7 (>20-60 lbs), E8 (>60-100 lbs), E9 (>100-250 lbs), E10 (>250-
  500 lbs), E11 (>500-675 lbs), E12 (>675-1,000 lbs), E16 (10,000 lbs).


                        Table 30--Low-Frequency Cetacean Ranges to Effects for Explosives
----------------------------------------------------------------------------------------------------------------
                                                    Range to
       Bin          Depth (m)    Cluster size      behavioral      Range to TTS          Range to AUD INJ
                                                  disturbance
----------------------------------------------------------------------------------------------------------------
E1...............        <=200               1  NA.............  350 m (149 m)..  99 m (4 m).
E1...............        <=200              25  1,625 m (321 m)  982 m (46 m)...  288 m (28 m).
E1...............        <=200             100  5,021 m (2,386   1,993 m (1,282   501 m (53 m).
                                                 m).              m).
E1...............         >200               1  NA.............  340 m (51 m)...  99 m (5 m).
E2...............        <=200               1  NA.............  375 m (6 m)....  98 m (0 m).
E3...............        <=200               1  NA.............  626 m (459 m)..  195 m (22 m).
E3...............        <=200              10  3,312 m (2,425   1,500 m (817 m)  371 m (62 m).
                                                 m).
E3...............         >200               1  NA.............  550 m (254 m)..  196 m (18 m).
E3...............         >200              10  1,743 m (1,121   1,000 m (333 m)  330 m (41 m).
                                                 m).
E4...............        <=200               1  NA.............  2,347 m (913 m)  353 m (120 m).
E4...............         >200               1  NA.............  1,000 m (152 m)  350 m (36 m).
E5...............        <=200               1  NA.............  956 m (1,114 m)  292 m (33 m).
E5...............        <=200               8  9,667 m (5,924   4,569 m (2,412   509 m (78 m).
                                                 m).              m).
E5...............         >200               1  NA.............  725 m (173 m)..  289 m (33 m).
E5...............         >200               8  1,750 m (1,640   1,250 m (793 m)  470 m (78 m).
                                                 m).
E6...............        <=200               1  NA.............  1,431 m (2,018   412 m (79 m).
                                                                  m).
E6...............        <=200               4  11,125 m (4,506  6,000 m (2,989   500 m (51 m).
                                                 m).              m).
E6...............         >200               1  NA.............  922 m (855 m)..  417 m (76 m).
E7...............        <=200               1  NA.............  2,818 m (1,316   492 m (147 m).
                                                                  m).
E7...............         >200               1  NA.............  2,822 m (1,165   495 m (173 m).
                                                                  m).

[[Page 19962]]

 
E8...............        <=200               1  NA.............  4,664 m (1,107   745 m (111 m).
                                                                  m).
E8...............         >200               1  NA.............  4,656 m (1,243   746 m (106 m).
                                                                  m).
E9...............        <=200               1  NA.............  4,954 m (2,390   656 m (92 m).
                                                                  m).
E9...............         >200               1  NA.............  4,786 m (3,126   623 m (92 m).
                                                                  m).
E10..............        <=200               1  NA.............  9,549 m (3,317   850 m (166 m).
                                                                  m).
E10..............         >200               1  NA.............  10,163 m (3,324  889 m (171 m).
                                                                  m).
E11..............        <=200               1  NA.............  17,248 m (5,803  2,753 m (791 m).
                                                                  m).
E11..............         >200               1  NA.............  15,925 m (5,288  2,625 m (668 m).
                                                                  m).
E12..............        <=200               1  NA.............  11,344 m (2,290  1,003 m (112 m).
                                                                  m).
E12..............         >200               1  NA.............  12,974 m (2,952  982 m (108 m).
                                                                  m).
E16..............         >200               1  NA.............  43,847 m (4,420  9,408 m (2,314 m).
                                                                  m).
----------------------------------------------------------------------------------------------------------------
Note: Behavioral response criteria are applied to explosive clusters >1. The values listed for TTS and AUD INJ
  are the greater of the respective SPL and SEL ranges. Median ranges are shown with standard deviation ranges
  in parentheses. The Action Proponents split the LF functional hearing group into LF and VLF based on Houser et
  al., (2024), however, NMFS updated acoustic technical guidance (NMFS, 2024) does not include these data but we
  have included the VLF group here for reference. E1 (0.1-0.25 lbs), E2 (>0.25-0.5 lbs), E3 (>0.5-2.5 lbs), E4
  (>2.5-5 lbs), E5 (>5-10 lbs), E6 (>10-20 lbs), E7 (>20-60 lbs), E8 (>60-100 lbs), E9 (>100-250 lbs), E10 (>250-
  500 lbs), E11 (>500-675 lbs), E12 (>675-1,000 lbs), E16 (10,000 lbs).


                       Table 31--High-Frequency Cetacean Ranges to Effects for Explosives
----------------------------------------------------------------------------------------------------------------
                                                    Range to
       Bin          Depth (m)    Cluster size      behavioral      Range to TTS          Range to AUD INJ
                                                  disturbance
----------------------------------------------------------------------------------------------------------------
E1...............        <=200               1  NA.............  110 m (19 m)...  45 m (1 m).
E1...............        <=200              25  757 m (71 m)...  514 m (49 m)...  113 m (6 m).
E1...............        <=200             100  1,004 m (133 m)  747 m (77 m)...  240 m (18 m).
E1...............         >200               1  NA.............  90 m (3 m).....  44 m (1 m).
E2...............        <=200               1  NA.............  156 m (1 m)....  45 m (1 m).
E3...............        <=200               1  NA.............  230 m (57 m)...  94 m (5 m).
E3...............        <=200              10  881 m (205 m)..  597 m (114 m)..  150 m (15 m).
E3...............         >200               1  NA.............  190 m (23 m)...  95 m (5 m).
E3...............         >200              10  525 m (172 m)..  366 m (79 m)...  120 m (7 m).
E4...............        <=200               1  NA.............  427 m (108 m)..  130 m (13 m).
E4...............         >200               1  NA.............  278 m (20 m)...  126 m (15 m).
E5...............        <=200               1  NA.............  370 m (118 m)..  138 m (11 m).
E5...............        <=200               8  1,083 m (343 m)  787 m (105 m)..  220 m (19 m).
E5...............         >200               1  NA.............  250 m (28 m)...  137 m (10 m).
E5...............         >200               8  625 m (209 m)..  450 m (139 m)..  170 m (10 m).
E6...............        <=200               1  NA.............  479 m (174 m)..  187 m (15 m).
E6...............        <=200               4  884 m (122 m)..  674 m (95 m)...  220 m (18 m).
E6...............         >200               1  NA.............  341 m (27 m)...  191 m (11 m).
E7...............        <=200               1  NA.............  544 m (67 m)...  239 m (18 m).
E7...............         >200               1  NA.............  552 m (68 m)...  237 m (20 m).
E8...............        <=200               1  NA.............  719 m (93 m)...  333 m (37 m).
E8...............         >200               1  NA.............  713 m (101 m)..  327 m (40 m).
E9...............        <=200               1  NA.............  731 m (90 m)...  336 m (29 m).
E9...............         >200               1  NA.............  739 m (99 m)...  325 m (31 m).
E10..............        <=200               1  NA.............  872 m (96 m)...  400 m (37 m).
E10..............         >200               1  NA.............  898 m (107 m)..  398 m (36 m).
E11..............        <=200               1  NA.............  1,857 m (420 m)  839 m (153 m).
E11..............         >200               1  NA.............  1,788 m (375 m)  840 m (159 m).
E12..............        <=200               1  NA.............  1,053 m (96 m).  490 m (43 m).
E12..............         >200               1  NA.............  1,053 m (67 m).  488 m (40 m).
E16..............         >200               1  NA.............  4,306 m (646 m)  1,986 m (367 m).
----------------------------------------------------------------------------------------------------------------
Note: Behavioral response criteria are applied to explosive clusters >1. The values listed for TTS and AUD INJ
  are the greater of the respective SPL and SEL ranges. Median ranges are shown with standard deviation ranges
  in parentheses. E1 (0.1-0.25 lbs), E2 (>0.25-0.5 lbs), E3 (>0.5-2.5 lbs), E4 (>2.5-5 lbs), E5 (>5-10 lbs), E6
  (>10-20 lbs), E7 (>20-60 lbs), E8 (>60-100 lbs), E9 (>100-250 lbs), E10 (>250-500 lbs), E11 (>500-675 lbs),
  E12 (>675-1,000 lbs), E16 (10,000 lbs).


                     Table 32--Very High-Frequency Cetacean Ranges to Effects for Explosives
----------------------------------------------------------------------------------------------------------------
                                                    Range to
       Bin          Depth (m)    Cluster size      behavioral      Range to TTS          Range to AUD INJ
                                                  disturbance
----------------------------------------------------------------------------------------------------------------
E1...............        <=200               1  NA.............  2,306 m (1,200   756 m (54 m).
                                                                  m).
E1...............        <=200              25  8,750 m (2,277   6,201 m (1,446   1,507 m (294 m).
                                                 m).              m).
E1...............        <=200             100  12,639 m (3,565  9,500 m (2,588   2,986 m (991 m).
                                                 m).              m).
E1...............         >200               1  NA.............  1,750 m (1,283   756 m (67 m).
                                                                  m).
E2...............        <=200               1  NA.............  2,319 m (189 m)  636 m (41 m).
E3...............        <=200               1  NA.............  4,229 m (1,812   1,369 m (214 m).
                                                                  m).

[[Page 19963]]

 
E3...............        <=200              10  12,403 m (5,829  9,181 m (4,143   2,319 m (986 m).
                                                 m).              m).
E3...............         >200               1  NA.............  3,188 m (2,063   1,358 m (218 m).
                                                                  m).
E3...............         >200              10  7,931 m (3,781   5,417 m (2,727   1,750 m (521 m).
                                                 m).              m).
E4...............        <=200               1  NA.............  7,708 m (3,229   3,718 m (510 m).
                                                                  m).
E4...............         >200               1  NA.............  6,956 m (940 m)  3,708 m (476 m).
E5...............        <=200               1  NA.............  6,188 m (2,432   2,389 m (607 m).
                                                                  m).
E5...............        <=200               8  16,743 m (6,550  12,785 m (4,590  3,708 m (1,410 m).
                                                 m).              m).
E5...............         >200               1  NA.............  5,139 m (1,394   2,400 m (650 m).
                                                                  m).
E5...............         >200               8  6,944 m (3,970   5,139 m (1,394   2,400 m (650 m).
                                                 m).              m).
E6...............        <=200               1  NA.............  8,450 m (1,848   4,163 m (982 m).
                                                                  m).
E6...............        <=200               4  14,139 m (2,139  10,806 m (1,894  4,163 m (982 m).
                                                 m).              m).
E6...............         >200               1  NA.............  8,161 m (1,685   4,142 m (886 m).
                                                                  m).
E7...............        <=200               1  NA.............  9,972 m (2,473   5,417 m (1,153 m).
                                                                  m).
E7...............         >200               1  NA.............  10,797 m (2,602  5,417 m (1,234 m).
                                                                  m).
E8...............        <=200               1  NA.............  15,042 m (2,913  8,474 m (1,510 m).
                                                                  m).
E8...............         >200               1  NA.............  14,576 m (2,952  8,508 m (1,647 m).
                                                                  m).
E9...............        <=200               1  NA.............  17,125 m (4,607  9,306 m (2,744 m).
                                                                  m).
E9...............         >200               1  NA.............  18,111 m (4,553  9,257 m (2,571 m).
                                                                  m).
E10..............        <=200               1  NA.............  23,389 m (5,616  14,477 m (3,639 m).
                                                                  m).
E10..............         >200               1  NA.............  24,140 m (5,392  14,360 m (3,368 m).
                                                                  m).
E11..............        <=200               1  NA.............  32,167 m (5,134  20,460 m (3,618 m).
                                                                  m).
E11..............         >200               1  NA.............  31,136 m (5,579  19,871 m (3,817 m).
                                                                  m).
E12..............        <=200               1  NA.............  22,356 m (4,938  13,444 m (3,602 m).
                                                                  m).
E12..............         >200               1  NA.............  23,368 m (4,434  14,097 m (2,913 m).
                                                                  m).
E16..............         >200               1  NA.............  63,764 m (5,297  46,979 m (5,225 m).
                                                                  m).
----------------------------------------------------------------------------------------------------------------
Note: Behavioral response criteria are applied to explosive clusters >1. The values listed for TTS and AUD INJ
  are the greater of the respective SPL and SEL ranges. Median ranges are shown with standard deviation ranges
  in parentheses. E1 (0.1-0.25 lbs), E2 (>0.25-0.5 lbs), E3 (>0.5-2.5 lbs), E4 (>2.5-5 lbs), E5 (>5-10 lbs), E6
  (>10-20 lbs), E7 (>20-60 lbs), E8 (>60-100 lbs), E9 (>100-250 lbs), E10 (>250-500 lbs), E11 (>500-675 lbs),
  E12 (>675-1,000 lbs), E16 (10,000 lbs).


                      Table 33--Phocid Carnivore in Water Ranges to Effects for Explosives
----------------------------------------------------------------------------------------------------------------
                                                    Range to
       Bin          Depth (m)    Cluster size      behavioral      Range to TTS          Range to AUD INJ
                                                  disturbance
----------------------------------------------------------------------------------------------------------------
E1...............        <=200               1  NA.............  342 m (110 m)..  88 m (4 m).
E1...............        <=200              25  1,493 m (265 m)  994 m (40 m)...  309 m (25 m).
E1...............        <=200             100  3,861 m (2,008   1,833 m (880 m)  500 m (52 m).
                                                 m).
E1...............         >200               1  NA.............  310 m (36 m)...  88 m (5 m).
E2...............        <=200               1  NA.............  382 m (5 m)....  91 m (1 m).
E3...............        <=200               1  NA.............  625 m (278 m)..  188 m (16 m).
E3...............        <=200              10  2,715 m (1,485   1,319 m (604 m)  393 m (50 m).
                                                 m).
E3...............         >200               1  NA.............  550 m (174 m)..  188 m (13 m).
E3...............         >200              10  1,500 m (909 m)  974 m (267 m)..  320 m (20 m).
E4...............        <=200               1  NA.............  1,569 m (638 m)  303 m (37 m).
E4...............         >200               1  NA.............  925 m (83 m)...  304 m (32 m).
E5...............        <=200               1  NA.............  879 m (736 m)..  273 m (22 m).
E5...............        <=200               8  5,840 m (3,339   2,611 m (1,253   517 m (61 m).
                                                 m).              m).
E5...............         >200               1  NA.............  625 m (144 m)..  270 m (20 m).
E5...............         >200               8  1,750 m (1,211   1,083 m (616 m)  420 m (50 m).
                                                 m).
E6...............        <=200               1  NA.............  1,055 m (1,248   361 m (40 m).
                                                                  m).
E6...............        <=200               4  6,556 m (3,277   2,410 m (1,313   487 m (43 m).
                                                 m).              m).
E6...............         >200               1  NA.............  725 m (178 m)..  368 m (29 m).
E7...............        <=200               1  NA.............  1,471 m (301 m)  418 m (35 m).
E7...............         >200               1  NA.............  1,480 m (304 m)  411 m (36 m).
E8...............        <=200               1  NA.............  2,974 m (660 m)  683 m (96 m).
E8...............         >200               1  NA.............  2,900 m (761 m)  704 m (92 m).
E9...............        <=200               1  NA.............  2,761 m (812 m)  611 m (88 m).
E9...............         >200               1  NA.............  2,713 m (702 m)  578 m (87 m).
E10..............        <=200               1  NA.............  4,917 m (1,223   770 m (117 m).
                                                                  m).
E10..............         >200               1  NA.............  4,967 m (1,132   790 m (148 m).
                                                                  m).
E11..............        <=200               1  NA.............  12,592 m (2,706  2,312 m (460 m).
                                                                  m).
E11..............         >200               1  NA.............  11,950 m (2,415  2,225 m (366 m).
                                                                  m).
E12..............        <=200               1  NA.............  5,578 m (1,142   903 m (110 m).
                                                                  m).
E12..............         >200               1  NA.............  6,146 m (1,343   869 m (93 m).
                                                                  m).
E16..............         >200               1  NA.............  24,319 m (1,977  5,478 m (1,106 m).
                                                                  m).
----------------------------------------------------------------------------------------------------------------
Note: Behavioral response criteria are applied to explosive clusters >1. The values listed for TTS and AUD INJ
  are the greater of the respective SPL and SEL ranges. Median ranges are shown with standard deviation ranges
  in parentheses. E1 (0.1-0.25 lbs), E2 (>0.25-0.5 lbs), E3 (>0.5-2.5 lbs), E4 (>2.5-5 lbs), E5 (>5-10 lbs), E6
  (>10-20 lbs), E7 (>20-60 lbs), E8 (>60-100 lbs), E9 (>100-250 lbs), E10 (>250-500 lbs), E11 (>500-675 lbs),
  E12 (>675-1,000 lbs), E16 (10,000 lbs).


[[Page 19964]]


                                Table 34--Explosive Ranges to Non-Auditory Injury and Mortality for All Marine Mammal Hearing Groups as a Function of Animal Mass
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
      Bin               Effect                   10 kg                    250 kg                   1,000 kg                  5,000 kg                  25,000 kg                72,000 kg
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
E1.............  Non-auditory injury.  22 m (0 m)..............  22 m (1 m)..............  22 m (1 m)..............  22 m (1 m)..............  22 m (0 m)..............  22 m (0 m).
E1.............  Mortality...........  4 m (0 m)...............  1 m (1 m)...............  0 m (0 m)...............  0 m (0 m)...............  0 m (0 m)...............  0 m (0 m).
E2.............  Non-auditory injury.  26 m (1 m)..............  25 m (1 m)..............  26 m (2 m)..............  26 m (0 m)..............  26 m (1 m)..............  26 m (0 m).
E2.............  Mortality...........  4 m (0 m)...............  2 m (1 m)...............  1 m (0 m)...............  0 m (0 m)...............  0 m (0 m)...............  0 m (0 m).
E3.............  Non-auditory injury.  47 m (1 m)..............  47 m (3 m)..............  46 m (5 m)..............  46 m (2 m)..............  46 m (2 m)..............  46 m (2 m).
E3.............  Mortality...........  10 m (1 m)..............  5 m (2 m)...............  2 m (1 m)...............  1 m (0 m)...............  0 m (0 m)...............  0 m (0 m).
E4.............  Non-auditory injury.  58 m (6 m)..............  58 m (6 m)..............  60 m (7 m)..............  64 m (6 m)..............  62 m (8 m)..............  64 m (5 m).
E4.............  Mortality...........  23 m (3 m)..............  12 m (4 m)..............  5 m (1 m)...............  3 m (1 m)...............  2 m (0 m)...............  1 m (0 m).
E5.............  Non-auditory injury.  74 m (4 m)..............  73 m (7 m)..............  73 m (10 m).............  75 m (4 m)..............  73 m (6 m)..............  75 m (4 m).
E5.............  Mortality...........  17 m (3 m)..............  9 m (3 m)...............  4 m (1 m)...............  3 m (1 m)...............  1 m (0 m)...............  1 m (0 m).
E6.............  Non-auditory injury.  95 m (4 m)..............  95 m (7 m)..............  94 m (11 m).............  97 m (5 m)..............  94 m (9 m)..............  97 m (4 m).
E6.............  Mortality...........  34 m (7 m)..............  16 m (6 m)..............  8 m (2 m)...............  5 m (1 m)...............  2 m (1 m)...............  1 m (0 m).
E7.............  Non-auditory injury.  121 m (8 m).............  122 m (9 m).............  121 m (15 m)............  125 m (7 m).............  117 m (18 m)............  125 m (7 m).
E7.............  Mortality...........  40 m (9 m)..............  19 m (7 m)..............  11 m (4 m)..............  7 m (2 m)...............  3 m (2 m)...............  2 m (1 m).
E8.............  Non-auditory injury.  206 m (38 m)............  159 m (19 m)............  159 m (21 m)............  162 m (18 m)............  158 m (20 m)............  165 m (19 m).
E8.............  Mortality...........  74 m (15 m).............  34 m (13 m).............  16 m (5 m)..............  11 m (2 m)..............  3 m (2 m)...............  3 m (1 m).
E9.............  Non-auditory injury.  207 m (77 m)............  184 m (13 m)............  179 m (16 m)............  189 m (11 m)............  174 m (11 m)............  196 m (11 m).
E9.............  Mortality...........  94 m (39 m).............  22 m (19 m).............  12 m (1 m)..............  8 m (1 m)...............  4 m (0 m)...............  3 m (0 m).
E10............  Non-auditory injury.  316 m (82 m)............  219 m (13 m)............  216 m (15 m)............  224 m (13 m)............  214 m (13 m)............  231 m (12 m).
E10............  Mortality...........  152 m (38 m)............  54 m (39 m).............  15 m (2 m)..............  10 m (1 m)..............  6 m (0 m)...............  4 m (0 m).
E11............  Non-auditory injury.  770 m (170 m)...........  421 m (154 m)...........  382 m (68 m)............  433 m (72 m)............  372 m (68 m)............  452 m (63 m).
E11............  Mortality...........  368 m (53 m)............  197 m (66 m)............  89 m (11 m).............  55 m (8 m)..............  25 m (5 m)..............  21 m (3 m).
E12............  Non-auditory injury.  475 m (99 m)............  277 m (16 m)............  275 m (19 m)............  277 m (19 m)............  273 m (17 m)............  298 m (16 m).
E12............  Mortality...........  235 m (52 m)............  118 m (53 m)............  18 m (10 m).............  13 m (1 m)..............  7 m (0 m)...............  5 m (0 m).
E16............  Non-auditory injury.  3,139 m (786 m).........  1,451 m (505 m).........  1,003 m (115 m).........  1,097 m (119 m).........  1,004 m (122 m).........  1,155 m (132 m).
E16............  Mortality...........  1,222 m (163 m).........  850 m (167 m)...........  491 m (62 m)............  350 m (34 m)............  189 m (10 m)............  134 m (18 m).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Median ranges with standard deviation ranges in parentheses. For non-auditory injury ranges, the greater of the respective ranges for 1 percent chance of gastro-intestinal tract injury
  and 1 percent chance of injury. E1 (0.1-0.25 lbs), E2 (>0.25-0.5 lbs), E3 (>0.5-2.5 lbs), E4 (>2.5-5 lbs), E5 (>5-10 lbs), E6 (>10-20 lbs), E7 (>20-60 lbs), E8 (>60-100 lbs), E9 (>100-250
  lbs), E10 (>250-500 lbs), E11 (>500-675 lbs), E12 (>675-1,000 lbs), E16 (10,000 lbs).

Marine Mammal Density

    A quantitative analysis of impacts on a species or stock requires 
data on their abundance and distribution that may be affected by 
anthropogenic activities in the potentially impacted area. The most 
appropriate metric for this type of analysis is density, which is the 
number of animals present per unit area. Marine species density 
estimation requires a significant amount of effort to both collect and 
analyze data to produce a reasonable estimate. Unlike surveys for 
terrestrial wildlife, many marine species spend much of their time 
submerged and are not easily observed. In order to collect enough 
sighting data to make reasonable density estimates, multiple 
observations are required, often in areas that are not easily 
accessible (e.g., far offshore). Ideally, marine mammal species 
sighting data would be collected for the specific area and time period 
(e.g., season) of interest and density estimates derived accordingly. 
However, in many places, poor weather conditions and high sea states 
prohibit the completion of comprehensive visual surveys.
    For most cetacean species, abundance is estimated using line-
transect surveys or mark-recapture studies (e.g., Barlow, 2010; Barlow 
and Forney, 2007; Calambokidis et al., 2008). This is the general 
approach applied in estimating cetacean abundance in NMFS SARs. 
Although the single value provides a good average estimate of abundance 
(total number of individuals) for a specified area, it does not provide 
information on the species distribution or concentrations within that 
area, and it does not estimate density for other timeframes or seasons 
that were not surveyed. More recently, spatial habitat modeling has 
been used to estimate cetacean densities (e.g., Roberts et al. 2023). 
These models estimate cetacean density as a continuous function of 
habitat variables (e.g., sea surface temperature, seafloor depth, etc.) 
and thus allow predictions of cetacean densities on finer spatial 
scales than traditional line-transect or mark recapture analyses, and 
for areas that have not been surveyed. Within the geographic area that 
was modeled, densities can be predicted wherever these habitat 
variables can be measured or estimated.
    Ideally, density data would be available for all species throughout 
the Study Area year-round, in order to best estimate the impacts of 
specified activities on marine species. However, in many places, vessel 
availability, lack of funding, inclement weather conditions, and high 
sea states prevent the completion of comprehensive year-round surveys. 
Even with surveys that are completed, poor conditions may result in 
lower sighting rates for species that would typically be sighted with 
greater frequency under favorable conditions. Lower sighting rates 
preclude having an acceptably low uncertainty in the density estimates. 
A high level of uncertainty, indicating a low level of confidence in 
the density estimate, is typical for species that are rare or difficult 
to sight. In areas where survey data are limited or non-existent, known 
or inferred associations between marine habitat features and the likely 
presence of specific species are sometimes used to predict densities in 
the absence of actual animal sightings. Consequently, there is no 
single source of density data for every area, species, and season 
because of the fiscal costs, resources, and effort involved in 
providing enough survey coverage to sufficiently estimate density.
    To characterize the marine species density for large oceanic 
regions, the Action Proponents review, critically assess, and 
prioritize existing density estimates from multiple sources, requiring 
the development of a systematic method for selecting the most 
appropriate density estimate for each combination of species/stock, 
area, and season. The selection and compilation of the best available 
marine species density data resulted in the NMSDD, which includes 
seasonal density values for every marine mammal species and stock 
present within the AFTT Study Area. This database is described in the 
``U.S. Navy Marine Species Density Database Phase IV for the Atlantic 
Fleet Training and Testing Study Area'' technical report (U.S. 
Department of the Navy, 2024),

[[Page 19965]]

hereafter referred to as the Density Technical Report. NMFS reviewed 
all cetacean densities provided by the Action Proponents prior to use 
in their acoustic analysis for the current rulemaking process.
    A variety of density data and density models are needed to develop 
a density database that encompasses the entirety of the AFTT Study 
Area. Because these data are collected using different methods with 
varying amounts of accuracy and uncertainty, the Action Proponents have 
developed a hierarchy to ensure the most accurate data is used when 
available. The Density Technical Report describes these models in 
detail and provides detailed explanations of the models applied to each 
species density estimate. The below list describes possible models in 
order of preference and use:
    1. Density estimates from spatial models are preferred and used 
when available because they provide an estimate with the least amount 
of uncertainty by deriving estimates for divided segments of the 
sampling area. These models (see DiMatteo et al. (2024), Garrison et 
al. (2023a, 2023b), and Roberts et al. (2023)) predict spatial 
variability of animal presence based on habitat variables (e.g., sea 
surface temperature, seafloor depth, etc.). Density spatial models are 
developed for areas, species, and, when available, specific timeframes 
(months or seasons) with sufficient survey data; therefore, this model 
cannot be used for species with low numbers of sightings. In the AFTT 
Study Area, density spatial models are available for certain species 
along the east coast to the offshore extent of available survey data 
and in the Gulf of America. For species not covered by the newer 
generation of models, the older Roberts et al. (2016) density estimates 
from Phase III could be used.
    2. Design-based density models predict animal density based on 
survey data. Like spatial density models, they are applied to areas 
with survey data. Design-based density models may be stratified, in 
which a density is predicted for each sub-region of a survey area, 
allowing for better prediction of species distribution across the 
density model area. In the AFTT Study Area, stratified density models 
are used for certain species on both the east coast and the Gulf of 
America. In addition, a few species' stratified density models are 
applied to areas east of regions with available survey data and cover a 
substantial portion of the Atlantic Ocean portion of the AFTT Study 
Area.
    3. Extrapolative models are used in areas where there is 
insufficient or no survey data. These models use a limited set of 
environmental variables to predict probable species densities based on 
environmental observations during actual marine mammal surveys (see 
Mannocci et al. (2017)). In the AFTT Study Area, extrapolative models 
are typically used east of regions with available survey data and cover 
a substantial portion of the Atlantic Ocean of the AFTT Study Area. 
Because some unsurveyed areas have oceanographic conditions that are 
very different from surveyed areas (e.g., the Labrador Sea and North 
Atlantic gyre) and some species models rely on a very limited data set, 
the predictions of some species' extrapolative density models and some 
regions of certain species' extrapolative density models are considered 
highly speculative. Extrapolative models are not used in the Gulf of 
America.
    4. Existing relative environmental suitability models include a 
high degree of uncertainty, but are applied when no other model is 
available.
    When interpreting the results of the quantitative analysis, as 
described in the Density Technical Report for Phase III (U.S. 
Department of the Navy, 2017), ``it is important to consider that even 
the best estimate of marine species density is really a model 
representation of the values of concentration where these animals might 
occur. Each model is limited to the variables and assumptions 
considered by the original data source provider. No mathematical model 
representation of any biological population is perfect and with regards 
to marine species biodiversity, any single model method will not 
completely explain the actual distribution and abundance of marine 
mammal species. It is expected that there would be anomalies in the 
results that need to be evaluated, with independent information for 
each case, to support if we might accept or reject a model or portions 
of the model.''
    The Action Proponents' estimates of abundance (based on density 
estimates used in the AFTT Study Area) utilize NMFS' SARs. For some 
species, the stock assessment for a given species may exceed the Navy's 
density prediction because those species' home range extends beyond the 
Study Area boundaries. For other species, the stock assessment 
abundance may be much less than the number of animals in the Navy's 
modeling given that the AFTT Study Area extends beyond the U.S. waters 
covered by the SAR abundance estimate. The primary source of density 
estimates are geographically specific survey data and either peer-
reviewed line-transect estimates or habitat-based density models that 
have been extensively validated to provide the most accurate estimates 
possible.
    NMFS coordinated with the Navy in the development of its take 
estimates and concurs that the Navy's approach for density 
appropriately utilizes the best available science. Later, in the 
Preliminary Analysis and Negligible Impact Determination section, we 
assess how the estimated take numbers compare to stock abundance in 
order to better understand the potential number of individuals 
impacted, and the rationale for which abundance estimate is used is 
included there.

Estimated Take From Acoustic Stressors

    The 2024 AFTT Draft Supplemental EIS/OEIS considered all military 
readiness activities proposed to occur in the AFTT Study Area that have 
the potential to result in the MMPA defined take of marine mammals. The 
Action Proponents determined that the three stressors below could 
result in the incidental taking of marine mammals. NMFS has reviewed 
the Action Proponents' data and analysis and determined that it is 
complete and accurate and agrees that the following stressors have the 
potential to result in takes by harassment of marine mammals from the 
specified activities:
     Acoustics (sonars and other transducers, air guns, pile 
driving/extraction);
     Explosives (explosive shock wave and sound, assumed to 
encompass the risk due to fragmentation); and
     Vessel strike.
    Acoustic and explosive sources are likely to result in incidental 
takes of marine mammals by harassment. Explosive sources and vessel 
strikes have the potential to result in incidental take by injury, 
serious injury, and/or mortality.
    The quantitative analysis process used for the 2024 AFTT Draft 
Supplemental EIS/OEIS and the application to estimate potential 
exposures to marine mammals resulting from acoustic and explosive 
stressors is detailed in the technical report titled ``Quantifying 
Acoustic Impacts on Marine Mammals and Sea Turtles: Methods and 
Analytical Approach for Phase IV Training and Testing'' (U.S. 
Department of the Navy, 2024).
    Regarding how avoidance of loud sources is considered in the take 
estimation, NAEMO does not simulate horizontal animat movement during 
an event. However, NAEMO approximates marine mammal avoidance of high 
sound levels due to exposure to sonars

[[Page 19966]]

in a one-dimensional calculation that scales how far an animat would be 
from a sound source based on sensitivity to disturbance, swim speed, 
and avoidance duration. This process reduces the sound exposure level 
(SEL), defined as the accumulation for a given animat (i.e., a virtual 
animal), by reducing the received sound pressure levels (SPL) of 
individual exposures based on a spherical spreading calculation from 
sources on each unique platform in an event. The onset of avoidance was 
based on the BRFs. Avoidance speeds and durations were informed by a 
review of available exposure and baseline data. This method captures a 
more accurate representation of avoidance by using the received sound 
levels, distance to platform, and species-specific criteria to 
calculate potential avoidance for each animat than the approach used in 
Phase III. However, this avoidance method may underestimate avoidance 
of long-duration sources with lower sound levels because it triggers 
avoidance calculations based on the highest modeled SPL received level 
exceeding p(0.5) on the BRF, rather than on cumulative exposure. This 
is because initiation of the avoidance calculation is based on the 
highest modeled SPL received level over p(0.5) on the BRF. Please see 
section 4.4.2.2 of the technical report titled ``Quantifying Acoustic 
Impacts on Marine Mammals and Sea Turtles: Methods and Analytical 
Approach for Phase IV Training and Testing'' (U.S. Department of the 
Navy, 2024).
    Regarding the consideration of mitigation effectiveness in the take 
estimation, during military readiness activities, there is typically at 
least one, if not numerous, support personnel involved in the activity 
(e.g., range support personnel aboard a torpedo retrieval boat or 
support aircraft). In addition to the Lookout posted for the purpose of 
mitigation, these additional personnel observe and disseminate marine 
species sighting information amongst the units participating in the 
activity whenever possible as they conduct their primary mission 
responsibilities. However, the quantitative analysis does not reduce 
model-estimated impacts to account for activity-based mitigation, as 
was done in previous phases of AFTT. While the activity-based 
mitigation is not quantitatively included in the take estimates, table 
2.3-1 of appendix A of the application indicates the percentage of the 
instances of take where an animal's closest point of approach was 
within a mitigation zone and, therefore, AUD INJ could potentially be 
mitigated. Note that these percentages do not account for other 
factors, such as the sightability of a given species or viewing 
conditions.
    Unlike activity-based mitigation, in some cases, implementation of 
the proposed geographic mitigation areas are incorporated into the 
quantitative analysis. The extent to which the mitigation areas reduce 
impacts on the affected species is addressed in the Preliminary 
Analysis and Negligible Impact Determination section.
    For additional information on the quantitative analysis process, 
refer to the technical report titled ``Quantifying Acoustic Impacts on 
Marine Mammals and Sea Turtles: Methods and Analytical Approach for 
Phase IV Training and Testing'' (U.S. Department of the Navy, 2024) and 
sections 6 and 11 of the application.
    As a general matter, NMFS does not prescribe the methods for 
estimating take for any applicant, but we review and ensure that 
applicants use the best available science, and methodologies that are 
logical and technically sound. Applicants may use different methods of 
calculating take (especially when using models) and still get to a 
result that is representative of the best available science and that 
allows for a rigorous and accurate evaluation of the effects on the 
affected populations. There are multiple pieces of the Navy's take 
estimation methods--propagation models, animat movement models, and 
behavioral thresholds, for example. NMFS evaluates the acceptability of 
these pieces as they evolve and are used in different rules and impact 
analyses. Some of the pieces of the Action Proponents' take estimation 
process have been used in Navy incidental take rules since 2009 and 
undergone multiple public comment processes; all of them have undergone 
extensive internal Navy review, and all of them have undergone 
comprehensive review by NMFS, which has sometimes resulted in 
modifications to methods or models.
    The Navy uses rigorous review processes (verification, validation, 
and accreditation processes; peer and public review) to ensure the data 
and methodology it uses represent the best available science. For 
instance, NAEMO is the result of a NMFS-led Center for Independent 
Experts (CIE) review of the components used in earlier models. The 
acoustic propagation component of NAEMO (CASS/GRAB) is accredited by 
the Oceanographic and Atmospheric Master Library (OAML), and many of 
the environmental variables used in NAEMO come from approved OAML 
databases and are based on in-situ data collection. The animal density 
components of NAEMO are base products of the NMSDD, which includes 
animal density components that have been validated and reviewed by a 
variety of scientists from NMFS Science Centers and academic 
institutions. Several components of the model, for example the Duke 
University habitat-based density models, have been published in peer 
reviewed literature. Additionally, NAEMO simulation components 
underwent quality assurance and quality control (QA/QC) review and 
validation for model parts such as the scenario builder, acoustic 
builder, scenario simulator, etc., conducted by qualified statisticians 
and modelers to ensure accuracy. Other models and methodologies have 
gone through similar review processes.
    In summary, we believe the Action Proponents' methods, including 
the method for incorporating avoidance, are the most appropriate 
methods for predicting AUD INJ, non-auditory injury, TTS, and 
behavioral disturbance. But even with the consideration of avoidance, 
given some of the more conservative components of the methodology 
(e.g., the thresholds do not consider ear recovery between pulses), we 
would describe the application of these methods as identifying the 
maximum number of instances in which marine mammals would be reasonably 
expected to be taken through AUD INJ, non-auditory injury, TTS, or 
behavioral disturbance.
    Based on the methods discussed in the previous sections and NAEMO, 
the Action Proponents provided their take estimate and request for 
authorization of takes incidental to the use of acoustic and explosive 
sources for military readiness activities annually (based on the 
maximum number of activities that could occur per 12-month period) and 
over the 7-year period, as well as the Navy's take request for ship 
shock trials, covered by the application. The following species/stocks 
present in the AFTT Study Area were modeled by the Navy and estimated 
to have 0 takes of any type from any activity source: Central Georgia 
Estuarine System stock of bottlenose dolphin, Northern South Carolina 
Estuarine System stock of bottlenose dolphin, and the Puerto Rico and 
U.S. Virgin Islands stock of sperm whale. NMFS has reviewed the Action 
Proponents' data, methodology, and analysis and determined that it is 
complete and accurate. NMFS agrees that the estimates for incidental 
takes by harassment from all sources requested for authorization are 
the maximum number of instances in which marine mammals are reasonably 
expected to be

[[Page 19967]]

taken and that the takes by mortality requested for authorization are 
for the maximum number of instances mortality or serious injury could 
occur, as in the case of ship shock trials and vessel strikes.
    Table 35, table 36, and table 37 summarize the maximum annual and 
7-year total amount and type of Level A harassment and Level B 
harassment that NMFS concurs is reasonably expected to occur by species 
and stock for Navy training activities, Navy testing activities, and 
Coast Guard training activities, respectively.

                    Table 35--Incidental Take Estimate by Stock Due to Acoustic and Explosive Sources During Navy Training Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                            Maximum      Maximum
                                                                             annual       annual      Maximum   7-Year total  7-Year total  7-Year total
                  Species                               Stock               Level B      Level A      annual       Level B       Level A      mortality
                                                                           harassment   harassment   mortality   harassment    harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale................  Western.....................           97            1           0           642             2             0
Blue whale................................  Western North Atlantic......           40            0           0           265             0             0
Bryde's whale.............................  Primary.....................           10            0           0            69             0             0
Fin whale.................................  Western North Atlantic......        1,089            6           0         7,585            38             0
Humpback whale............................  Gulf of Maine...............          341            7           0         2,351            41             0
Minke whale...............................  Canadian East Coast.........        2,606           18           0        17,676           120             0
Rice's whale..............................  Northern Gulf of America....            8            1           0            49             1             0
Sei whale.................................  Nova Scotia.................          356            3           0         2,430            17             0
Sperm whale...............................  North Atlantic..............        7,189            3           0        50,266             5             0
Sperm whale...............................  Northern Gulf of America....           38            0           0           254             0             0
Dwarf sperm whale.........................  Northern Gulf of America....           14            1           0            87             1             0
Pygmy sperm whale.........................  Northern Gulf of America....           15            2           0            96             2             0
Dwarf sperm whale.........................  Western North Atlantic......        3,678           32           0        25,551           221             0
Pygmy sperm whale.........................  Western North Atlantic......        3,625           34           0        25,175           231             0
Blainville's beaked whale.................  Northern Gulf of America....           12            0           0            79             0             0
Goose-beaked whale........................  Northern Gulf of America....           41            0           0           281             0             0
Gervais' beaked whale.....................  Northern Gulf of America....           14            0           0            90             0             0
Blainville's beaked whale.................  Western North Atlantic......       15,267            1           0       106,751             1             0
Goose-beaked whale........................  Western North Atlantic......       66,011            1           0       461,356             3             0
Gervais' beaked whale.....................  Western North Atlantic......       15,761            0           0       110,198             0             0
Northern bottlenose whale.................  Western North Atlantic......          828            0           0         5,789             0             0
Sowerby's beaked whale....................  Western North Atlantic......       15,846            0           0       110,804             0             0
True's beaked whale.......................  Western North Atlantic......       15,892            0           0       111,111             0             0
Atlantic spotted dolphin..................  Northern Gulf of America....          792            1           0         5,515             4             0
Bottlenose dolphin........................  Gulf of America Eastern                29            0           0           126             0             0
                                             Coastal.
Bottlenose dolphin........................  Gulf of America Northern            2,094            1           0        14,645             2             0
                                             Coastal.
Bottlenose dolphin........................  Gulf of America Oceanic.....          517            1           0         3,611             1             0
Bottlenose dolphin........................  Gulf of America Western               791            0           0         2,372             0             0
                                             Coastal.
Bottlenose dolphin........................  Mississippi Sound, Lake             1,564            0           0        10,944             0             0
                                             Borgne, and Bay Boudreau.
Bottlenose dolphin........................  Northern Gulf of America            4,665            3           0        31,959            13             0
                                             Continental Shelf.
Bottlenose dolphin........................  Nueces and Corpus Christi               4            0           0            11             0             0
                                             Bays.
Bottlenose dolphin........................  Sabine Lake.................            1            0           0             2             0             0
Bottlenose dolphin........................  St. Andrew Bay..............           14            0           0            92             0             0
Bottlenose dolphin........................  St. Joseph Bay..............            7            0           0            47             0             0
Bottlenose dolphin........................  Tampa Bay...................          350            0           0         1,050             0             0
Clymene dolphin...........................  Northern Gulf of America....           66            0           0           459             0             0
False killer whale........................  Northern Gulf of America....           24            0           0           160             0             0
Fraser's dolphin..........................  Northern Gulf of America....           25            0           0           159             0             0
Killer whale..............................  Northern Gulf of America....           13            0           0            82             0             0
Melon-headed whale........................  Northern Gulf of America....           81            0           0           561             0             0
Pygmy killer whale........................  Northern Gulf of America....           29            0           0           198             0             0
Risso's dolphin...........................  Northern Gulf of America....           23            0           0           155             0             0
Rough-toothed dolphin.....................  Northern Gulf of America....          128            0           0           866             0             0
Short-finned pilot whale..................  Northern Gulf of America....           88            0           0           611             0             0
Striped dolphin...........................  Northern Gulf of America....          244            1           0         1,696             1             0
Pantropical spotted dolphin...............  Northern Gulf of America....          720            3           0         5,036             5             0
Spinner dolphin...........................  Northern Gulf of America....           20            0           0           135             0             0
Atlantic white-sided dolphin..............  Western North Atlantic......        3,233            4           0        22,590            18             0
Common dolphin............................  Western North Atlantic......      165,863           39           0     1,160,553           261             0
Atlantic spotted dolphin..................  Western North Atlantic......       74,649           27           0       508,116           179             0
Bottlenose dolphin........................  Indian River Lagoon                 1,422            0           0         9,601             0             0
                                             Estuarine System.
Bottlenose dolphin........................  Jacksonville Estuarine                348            0           0         2,408             0             0
                                             System.
Bottlenose dolphin........................  Northern Georgia/Southern               2            0           0             6             0             0
                                             South Carolina Estuarine
                                             System.
Bottlenose dolphin........................  Northern North Carolina             9,181            3           0        63,391            20             0
                                             Estuarine System.
Bottlenose dolphin........................  Southern Georgia Estuarine            122            1           0           710             1             0
                                             System.
Bottlenose dolphin........................  Southern North Carolina               162            0           0           535             0             0
                                             Estuarine System.
Tamanend's bottlenose dolphin.............  Western North Atlantic              7,692            2           0        49,736             6             0
                                             Central Florida Coastal.
Tamanend's bottlenose dolphin.............  Western North Atlantic             17,003            2           0       116,702             4             0
                                             Northern Florida Coastal.
Bottlenose dolphin........................  Western North Atlantic             64,712           34           0       450,293           227             0
                                             Northern Migratory Coastal.
Bottlenose dolphin........................  Western North Atlantic            120,151           27           1       818,458           173             1
                                             Offshore.
Tamanend's bottlenose dolphin.............  Western North Atlantic South        3,867            3           1        24,408            11             1
                                             Carolina/Georgia Coastal.

[[Page 19968]]

 
Bottlenose dolphin........................  Western North Atlantic              8,868            7           0        56,933            44             0
                                             Southern Migratory Coastal.
Clymene dolphin...........................  Western North Atlantic......       69,460           15           1       486,205            94             3
False killer whale........................  Western North Atlantic......          406            0           0         2,821             0             0
Fraser's dolphin..........................  Western North Atlantic......        1,904            2           0        12,826             8             0
Killer whale..............................  Western North Atlantic......          110            0           0           759             0             0
Long-finned pilot whale...................  Western North Atlantic......       13,501            5           0        94,499            18             0
Melon-headed whale........................  Western North Atlantic......        3,517            1           0        23,968             2             0
Pantropical spotted dolphin...............  Western North Atlantic......       10,976            3           0        75,620            12             0
Pygmy killer whale........................  Western North Atlantic......          368            1           0         2,512             1             0
Risso's dolphin...........................  Western North Atlantic......       22,128            5           0       150,830            24             0
Rough-toothed dolphin.....................  Western North Atlantic......        3,365            3           0        22,647            10             0
Short-finned pilot whale..................  Western North Atlantic......       21,745            3           0       149,080            18             0
Spinner dolphin...........................  Western North Atlantic......        4,185            1           0        28,962             3             0
Striped dolphin...........................  Western North Atlantic......      121,279           26           0       848,940           178             0
White-beaked dolphin......................  Western North Atlantic......            4            0           0            27             0             0
Harbor porpoise...........................  Gulf of Maine/Bay of Fundy..       36,396           73           0       253,899           505             0
Gray seal.................................  Western North Atlantic......        7,862           14           0        54,598            93             0
Harbor seal...............................  Western North Atlantic......       11,207           18           0        77,914           125             0
Harp seal.................................  Western North Atlantic......       14,632            2           0       102,365            12             0
Hooded seal...............................  Western North Atlantic......          460            1           0         3,205             1             0
--------------------------------------------------------------------------------------------------------------------------------------------------------


                     Table 36--Incidental Take Estimate by Stock Due to Acoustic and Explosive Source During Navy Testing Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                            Maximum      Maximum
                                                                             annual       annual      Maximum   7-Year total  7-Year total  7-Year total
                  Species                               Stock               Level B      Level A      annual       Level B       Level A      mortality
                                                                           harassment   harassment   mortality   harassment    harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale................  Western.....................          316            1           0         2,036             6             0
Blue whale................................  Western North Atlantic......           31            1           0           199             2             0
Bryde's whale.............................  Primary.....................            1            0           0             1             0             0
Fin whale.................................  Western North Atlantic......        1,524           15           0         9,710            93             0
Humpback whale............................  Gulf of Maine...............          500            5           0         3,186            33             0
Minke whale...............................  Canadian East Coast.........        2,032           38           0        13,316           257             0
Rice's whale..............................  Northern Gulf of America....          294            2           0         1,997             5             0
Sei whale.................................  Nova Scotia.................          389            4           0         2,549            27             0
Sperm whale...............................  North Atlantic..............        5,395            4           0        34,373            16             0
Sperm whale...............................  Northern Gulf of America....          237            0           0         1,399             0             0
Dwarf sperm whale.........................  Northern Gulf of America....          173           21           0         1,023            72             0
Pygmy sperm whale.........................  Northern Gulf of America....          158           20           0           919            63             0
Dwarf sperm whale.........................  Western North Atlantic......        2,640          147           0        16,951           962             0
Pygmy sperm whale.........................  Western North Atlantic......        2,663          141           0        17,096           925             0
Blainville's beaked whale.................  Northern Gulf of America....          114            0           0           733             0             0
Goose-beaked whale........................  Northern Gulf of America....          419            0           0         2,681             0             0
Gervais' beaked whale.....................  Northern Gulf of America....          111            0           0           710             0             0
Blainville's beaked whale.................  Western North Atlantic......       10,431            0           0        65,790             0             0
Goose-beaked whale........................  Western North Atlantic......       46,017            1           0       290,954             2             0
Gervais' beaked whale.....................  Western North Atlantic......        9,678            1           0        62,096             1             0
Northern bottlenose whale.................  Western North Atlantic......          823            1           0         5,090             1             0
Sowerby's beaked whale....................  Western North Atlantic......        9,770            1           0        62,705             1             0
True's beaked whale.......................  Western North Atlantic......        9,684            0           0        62,151             0             0
Atlantic spotted dolphin..................  Northern Gulf of America....       11,976           19           0        78,071           119             0
Bottlenose dolphin........................  Gulf of America Eastern                51            0           0           329             0             0
                                             Coastal.
Bottlenose dolphin........................  Gulf of America Northern            5,052           16           0        35,305           112             0
                                             Coastal.
Bottlenose dolphin........................  Gulf of America Oceanic.....        5,755            3           0        36,970            10             0
Bottlenose dolphin........................  Gulf of America Western             2,540            1           0        15,751             1             0
                                             Coastal.
Bottlenose dolphin........................  Mississippi Sound, Lake               194            1           0         1,070             1             0
                                             Borgne, and Bay Boudreau.
Bottlenose dolphin........................  Northern Gulf of America           66,581           25           0       448,847           151             0
                                             Continental Shelf.
Bottlenose dolphin........................  St. Andrew Bay..............           32            0           0           211             0             0
Bottlenose dolphin........................  St. Joseph Bay..............           35            0           0           240             0             0
Clymene dolphin...........................  Northern Gulf of America....          533            3           0         3,118             4             0
False killer whale........................  Northern Gulf of America....          206            0           0         1,263             0             0
Fraser's dolphin..........................  Northern Gulf of America....          216            0           0         1,328             0             0
Killer whale..............................  Northern Gulf of America....           97            0           0           598             0             0
Melon-headed whale........................  Northern Gulf of America....          690            1           0         4,245             1             0
Pygmy killer whale........................  Northern Gulf of America....          256            0           0         1,575             0             0
Risso's dolphin...........................  Northern Gulf of America....          180            0           0         1,097             0             0
Rough-toothed dolphin.....................  Northern Gulf of America....        1,510            3           0         9,920             5             0
Short-finned pilot whale..................  Northern Gulf of America....          933            3           0         5,572            13             0
Striped dolphin...........................  Northern Gulf of America....        2,132            6           1        13,718            14             2
Pantropical spotted dolphin...............  Northern Gulf of America....        5,596            6           2        34,923            23             5
Spinner dolphin...........................  Northern Gulf of America....          636            0           0         4,324             0             0

[[Page 19969]]

 
Atlantic white-sided dolphin..............  Western North Atlantic......        7,662            5           0        49,052            25             0
Common dolphin............................  Western North Atlantic......      103,523          121           0       659,876           753             0
Atlantic spotted dolphin..................  Western North Atlantic......       46,117           60           0       288,483           398             0
Bottlenose dolphin........................  Indian River Lagoon                   154            0           0         1,074             0             0
                                             Estuarine System.
Bottlenose dolphin........................  Jacksonville Estuarine                 12            0           0            69             0             0
                                             System.
Bottlenose dolphin........................  Northern North Carolina               851            3           0         5,151            17             0
                                             Estuarine System.
Bottlenose dolphin........................  Southern Georgia Estuarine              1            0           0             1             0             0
                                             System.
Tamanend's bottlenose dolphin.............  Western North Atlantic              2,797            1           0        16,626             4             0
                                             Central Florida Coastal.
Tamanend's bottlenose dolphin.............  Western North Atlantic              4,382            3           0        26,243             9             0
                                             Northern Florida Coastal.
Bottlenose dolphin........................  Western North Atlantic              6,236           26           0        37,917           148             0
                                             Northern Migratory Coastal.
Bottlenose dolphin........................  Western North Atlantic             66,789           76           1       427,270           504             1
                                             Offshore.
Tamanend's bottlenose dolphin.............  Western North Atlantic South        1,092            3           0         6,372            11             0
                                             Carolina/Georgia Coastal.
Bottlenose dolphin........................  Western North Atlantic              1,015            2           0         5,874             8             0
                                             Southern Migratory Coastal.
Clymene dolphin...........................  Western North Atlantic......       63,262           89           0       416,118           604             0
False killer whale........................  Western North Atlantic......          165            1           0         1,050             1             0
Fraser's dolphin..........................  Western North Atlantic......        1,000            1           0         6,602             6             0
Killer whale..............................  Western North Atlantic......           69            1           0           435             1             0
Long-finned pilot whale...................  Western North Atlantic......        8,177            7           0        51,507            45             0
Melon-headed whale........................  Western North Atlantic......        1,078            2           0         7,099            10             0
Pantropical spotted dolphin...............  Western North Atlantic......        2,087            2           0        13,525            13             0
Pygmy killer whale........................  Western North Atlantic......          108            0           0           712             0             0
Risso's dolphin...........................  Western North Atlantic......       15,103           20           0        95,004           119             0
Rough-toothed dolphin.....................  Western North Atlantic......        1,386            3           0         8,901            15             0
Short-finned pilot whale..................  Western North Atlantic......       11,275           12           0        72,834            73             0
Spinner dolphin...........................  Western North Atlantic......        1,168            1           0         7,536             7             0
Striped dolphin...........................  Western North Atlantic......       87,521          137           0       548,894           931             0
White-beaked dolphin......................  Western North Atlantic......           12            0           0            76             0             0
Harbor porpoise...........................  Gulf of Maine/Bay of Fundy..       50,625           70           0       332,156           421             0
Gray seal.................................  Western North Atlantic......        7,813           10           0        50,645            58             0
Harbor seal...............................  Western North Atlantic......       10,813           13           0        70,072            78             0
Harp seal.................................  Western North Atlantic......       11,156            3           0        72,257            15             0
Hooded seal...............................  Western North Atlantic......        1,264            1           0         7,777             4             0
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: All Navy Testing estimated mortalities are due to ship shock trials without consideration of extensive mitigation measures


                Table 37--Incidental Take Estimate by Stock Due to Acoustic and Explosive Sources During Coast Guard Training Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                            Maximum      Maximum
                                                                             annual       annual      Maximum   7-Year total  7-Year total  7-Year total
                  Species                               Stock               Level B      Level A      annual       Level B       Level A      mortality
                                                                           harassment   harassment   mortality   harassment    harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale................  Western.....................            1            0           0             4             0             0
Fin whale.................................  Western North Atlantic......            3            0           0             3             0             0
Humpback whale............................  Gulf of Maine...............            3            0           0             7             0             0
Minke whale...............................  Canadian East Coast.........            5            0           0            14             0             0
Rice's whale..............................  Northern Gulf of America....            1            0           0             1             0             0
Sei whale.................................  Nova Scotia.................            2            0           0             2             0             0
Sperm whale...............................  North Atlantic..............            6            0           0            36             0             0
Dwarf sperm whale.........................  Northern Gulf of America....            2            0           0             2             0             0
Pygmy sperm whale.........................  Northern Gulf of America....            2            0           0             2             0             0
Dwarf sperm whale.........................  Western North Atlantic......            8            1           0            45             1             0
Pygmy sperm whale.........................  Western North Atlantic......            6            1           0            31             1             0
Blainville's beaked whale.................  Western North Atlantic......            7            0           0            46             0             0
Goose-beaked whale........................  Western North Atlantic......           42            0           0           277             0             0
Gervais' beaked whale.....................  Western North Atlantic......            7            0           0            45             0             0
Sowerby's beaked whale....................  Western North Atlantic......            6            0           0            37             0             0
True's beaked whale.......................  Western North Atlantic......            6            0           0            39             0             0
Atlantic spotted dolphin..................  Northern Gulf of America....           36            0           0           241             0             0
Bottlenose dolphin........................  Gulf of America Oceanic.....            2            0           0             3             0             0
Bottlenose dolphin........................  Northern Gulf of America               85            1           0           585             1             0
                                             Continental Shelf.
Rough-toothed dolphin.....................  Northern Gulf of America....            4            0           0            22             0             0
Atlantic white-sided dolphin..............  Western North Atlantic......            6            0           0            27             0             0
Common dolphin............................  Western North Atlantic......           19            1           0           127             1             0
Atlantic spotted dolphin..................  Western North Atlantic......           32            0           0           205             0             0
Bottlenose dolphin........................  Northern North Carolina               500            0           0         3,494             0             0
                                             Estuarine System.
Tamanend's bottlenose dolphin.............  Western North Atlantic                  5            0           0            30             0             0
                                             Central Florida Coastal.

[[Page 19970]]

 
Bottlenose dolphin........................  Western North Atlantic              2,772            0           0        19,400             0             0
                                             Northern Migratory Coastal.
Bottlenose dolphin........................  Western North Atlantic                106            0           0           723             0             0
                                             Offshore.
Tamanend's bottlenose dolphin.............  Western North Atlantic South            1            0           0             1             0             0
                                             Carolina/Georgia Coastal.
Bottlenose dolphin........................  Western North Atlantic                297            0           0         2,076             0             0
                                             Southern Migratory Coastal.
Clymene dolphin...........................  Western North Atlantic......            1            0           0             1             0             0
False killer whale........................  Western North Atlantic......            1            0           0             1             0             0
Fraser's dolphin..........................  Western North Atlantic......            1            0           0             7             0             0
Killer whale..............................  Western North Atlantic......            1            0           0             1             0             0
Long-finned pilot whale...................  Western North Atlantic......            2            0           0             3             0             0
Melon-headed whale........................  Western North Atlantic......            3            0           0            19             0             0
Pantropical spotted dolphin...............  Western North Atlantic......            5            0           0            29             0             0
Pygmy killer whale........................  Western North Atlantic......            1            0           0             2             0             0
Risso's dolphin...........................  Western North Atlantic......            8            0           0            43             0             0
Rough-toothed dolphin.....................  Western North Atlantic......            2            0           0            14             0             0
Short-finned pilot whale..................  Western North Atlantic......           15            0           0            93             0             0
Spinner dolphin...........................  Western North Atlantic......            3            0           0            15             0             0
Striped dolphin...........................  Western North Atlantic......            2            0           0             4             0             0
Harbor porpoise...........................  Gulf of Maine/Bay of Fundy..           98            4           0           677            28             0
Gray seal.................................  Western North Atlantic......           49            0           0           342             0             0
Harbor seal...............................  Western North Atlantic......           74            1           0           500             1             0
Harp seal.................................  Western North Atlantic......            4            1           0            27             1             0
Hooded seal...............................  Western North Atlantic......            2            0           0             3             0             0
--------------------------------------------------------------------------------------------------------------------------------------------------------

Estimated Take From Sonar and Other Transducers
    Table 38, table 39, and table 40 provide estimated effects from 
sonar and other transducers, including the comparative amounts of TTS 
and behavioral disturbance for each species and stock annually, noting 
that if a modeled marine mammal was ``taken'' through exposure to both 
TTS and behavioral disturbance in the model, it was recorded as a TTS. 
Of note, a higher proportion of the takes by Level B harassment of 
mysticetes include the potential for TTS (as compared to other taxa and 
prior rules) due to a combination of the fact that mysticetes are 
relatively less sensitive to behavioral disturbance and the number of 
auditory impacts from sonar (both TTS and AUD INJ) have increased for 
some species since the Phase III analysis (84 FR 70712, December 23, 
2019) largely due to changes in how avoidance was modeled; for some 
stocks, changes in densities in areas that overlap activities have also 
contributed to increased or decreased impacts compared to those modeled 
in Phase III.
    Additionally, although the Navy proposes to use substantially fewer 
hours of hull-mounted sonars in this action compared to the Phase III 
analysis, the updated HF cetacean criteria reflect greater 
susceptibility to auditory effects at low and mid-frequencies than 
previously analyzed. Consequently, the predicted auditory effects due 
to sources under 10 kHz, including but not limited to MF1 hull-mounted 
sonar and other anti-submarine warfare sonars, are substantially higher 
for this auditory group than in prior analyses of the same activities. 
Thus, for activities with sonars, some modeled exposures that would 
previously have been categorized as significant behavioral responses 
may now instead be counted as auditory effects (TTS and AUD INJ). 
Similarly, the updated HF cetacean criteria reflect greater 
susceptibility to auditory effects at low and mid-frequencies in 
impulsive sounds. For VHF cetaceans, susceptibility to auditory effects 
has not changed substantially since the prior analysis.

       Table 38--Annual and 7-Year Estimated Take of Marine Mammal Stocks From Sonar and Other Active Transducers During Navy Training Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                    Maximum                 Maximum   Maximum 7-              Maximum 7-
                    Species                                   Stock                 annual      Maximum   annual AUD     year     Maximum 7-   year AUD
                                                                                  behavioral  annual TTS      INJ     behavioral   year TTS       INJ
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale....................  Western.........................          17          56           1         113         370           2
Blue whale....................................  Western North Atlantic..........           6          32           0          42         220           0
Bryde's whale.................................  Primary.........................           1           9           -           6          63           -
Fin whale.....................................  Western North Atlantic..........         218         833           6       1,520       5,810          38
Humpback whale................................  Gulf of Maine...................          56         264           6         387       1,827          40
Minke whale...................................  Canadian East Coast.............         239       2,332          17       1,665      15,771         113
Rice's whale..................................  Northern Gulf of America........           1           6           1           7          41           1
Sei whale.....................................  Nova Scotia.....................          38         313           3         264       2,136          17
Sperm whale...................................  North Atlantic..................       5,692       1,487           1      39,824      10,380           1
Sperm whale...................................  Northern Gulf of America........          32           4           -         224          28           -
Dwarf sperm whale.............................  Northern Gulf of America........           2           8           0          14          55           0
Pygmy sperm whale.............................  Northern Gulf of America........           2           9           1          14          61           1
Dwarf sperm whale.............................  Western North Atlantic..........         743       2,875          25       5,191      19,945         174
Pygmy sperm whale.............................  Western North Atlantic..........         774       2,792          25       5,409      19,359         171
Blainville's beaked whale.....................  Northern Gulf of America........          12           0           -          79           0           -
Goose-beaked whale............................  Northern Gulf of America........          40           1           -         280           1           -
Gervais' beaked whale.........................  Northern Gulf of America........          13           1           -          89           1           -

[[Page 19971]]

 
Blainville's beaked whale.....................  Western North Atlantic..........      15,211          53           -     106,367         371           -
Goose-beaked whale............................  Western North Atlantic..........      65,767         234           -     459,656       1,636           -
Gervais' beaked whale.........................  Western North Atlantic..........      15,616         143           -     109,195         999           -
Northern bottlenose whale.....................  Western North Atlantic..........         824           4           -       5,765          24           -
Sowerby's beaked whale........................  Western North Atlantic..........      15,679         165           -     109,639       1,153           -
True's beaked whale...........................  Western North Atlantic..........      15,721         169           -     109,931       1,178           -
Atlantic spotted dolphin......................  Northern Gulf of America........         508         280           0       3,544       1,948           0
Bottlenose dolphin............................  Gulf of America Eastern Coastal.          27           -           -         115           -           -
Bottlenose dolphin............................  Gulf of America Northern Coastal         197           -           -       1,379           -           -
Bottlenose dolphin............................  Gulf of America Oceanic.........         432          83           1       3,024         580           1
Bottlenose dolphin............................  Gulf of America Western Coastal.         359         432           -       1,076       1,296           -
Bottlenose dolphin............................  Northern Gulf of America               4,268         364           0      29,367       2,365           0
                                                 Continental Shelf.
Bottlenose dolphin............................  Nueces and Corpus Christi Bays..           4           -           -          11           -           -
Bottlenose dolphin............................  Sabine Lake.....................           1           -           -           2           -           -
Bottlenose dolphin............................  St. Andrew Bay..................          14           -           -          92           -           -
Bottlenose dolphin............................  St. Joseph Bay..................           7           -           -          47           -           -
Bottlenose dolphin............................  Tampa Bay.......................         163         187           -         490         560           -
Clymene dolphin...............................  Northern Gulf of America........          35          31           0         242         217           0
False killer whale............................  Northern Gulf of America........          15           9           -          99          61           -
Fraser's dolphin..............................  Northern Gulf of America........          17           6           -         119          38           -
Killer whale..................................  Northern Gulf of America........           8           5           -          51          31           -
Melon-headed whale............................  Northern Gulf of America........          53          28           -         366         195           -
Pygmy killer whale............................  Northern Gulf of America........          18          11           -         125          73           -
Risso's dolphin...............................  Northern Gulf of America........          16           7           0         109          46           0
Rough-toothed dolphin.........................  Northern Gulf of America........          89          37           -         617         245           -
Short-finned pilot whale......................  Northern Gulf of America........          54          33           0         377         231           0
Striped dolphin...............................  Northern Gulf of America........         186          57           0       1,300         394           0
Pantropical spotted dolphin...................  Northern Gulf of America........         498         220           1       3,486       1,538           1
Spinner dolphin...............................  Northern Gulf of America........          12           8           0          80          55           0
Atlantic white-sided dolphin..................  Western North Atlantic..........       2,051       1,172           2      14,333       8,190           8
Common dolphin................................  Western North Atlantic..........      83,926      81,845          33     587,262     572,658         228
Atlantic spotted dolphin......................  Western North Atlantic..........      34,866      39,711          22     241,359     266,255         151
Bottlenose dolphin............................  Indian River Lagoon Estuarine          1,421           1           0       9,598           3           0
                                                 System.
Bottlenose dolphin............................  Jacksonville Estuarine System...         264          84           -       1,825         583           -
Bottlenose dolphin............................  Northern Georgia/Southern South            2           -           -           6           -           -
                                                 Carolina Estuarine System.
Bottlenose dolphin............................  Northern North Carolina                7,653       1,527           3      53,027      10,363          20
                                                 Estuarine System.
Bottlenose dolphin............................  Southern Georgia Estuarine                84          38           1         498         212           1
                                                 System.
Bottlenose dolphin............................  Southern North Carolina                   81          80           -         255         279           -
                                                 Estuarine System.
Tamanend's bottlenose dolphin.................  Western North Atlantic Central         6,517       1,157           0      44,348       5,270           0
                                                 Florida Coastal.
Tamanend's bottlenose dolphin.................  Western North Atlantic Northern       15,287       1,711           1     106,216      10,461           3
                                                 Florida Coastal.
Bottlenose dolphin............................  Western North Atlantic Northern       52,040      12,610          28     363,648      86,215         196
                                                 Migratory Coastal.
Bottlenose dolphin............................  Western North Atlantic Offshore.      62,316      57,732          20     431,069     386,677         131
Tamanend's bottlenose dolphin.................  Western North Atlantic South           1,172       2,685           2       7,399      16,942           8
                                                 Carolina/Georgia Coastal.
Bottlenose dolphin............................  Western North Atlantic Southern        2,345       6,475           2      15,085      41,513          14
                                                 Migratory Coastal.
Clymene dolphin...............................  Western North Atlantic..........      39,694      29,729           8     277,855     208,097          54
False killer whale............................  Western North Atlantic..........         236         170           -       1,647       1,174           -
Fraser's dolphin..............................  Western North Atlantic..........       1,000         902           1       6,872       5,948           6
Killer whale..................................  Western North Atlantic..........          68          42           0         476         283           0
Long-finned pilot whale.......................  Western North Atlantic..........       8,540       4,954           2      59,774      34,676           8
Melon-headed whale............................  Western North Atlantic..........       1,684       1,833           1      11,682      12,286           2
Pantropical spotted dolphin...................  Western North Atlantic..........       5,641       5,332           2      39,262      36,344          11
Pygmy killer whale............................  Western North Atlantic..........         185         183           0       1,283       1,229           0
Risso's dolphin...............................  Western North Atlantic..........      12,425       9,694           3      86,042      64,728          21
Rough-toothed dolphin.........................  Western North Atlantic..........       1,444       1,917           2       9,949      12,681           9
Short-finned pilot whale......................  Western North Atlantic..........      12,319       9,414           2      85,503      63,500          11
Spinner dolphin...............................  Western North Atlantic..........       2,193       1,991           1      15,284      13,673           3
Striped dolphin...............................  Western North Atlantic..........      69,973      51,282          22     489,808     358,968         153
White-beaked dolphin..........................  Western North Atlantic..........           3           1           -          20           7           -
Harbor porpoise...............................  Gulf of Maine/Bay of Fundy......      34,065       2,022           6     237,737      14,003          41
Gray seal.....................................  Western North Atlantic..........       5,241       2,531          11      36,379      17,593          73
Harbor seal...................................  Western North Atlantic..........       7,331       3,737          14      51,139      25,808          97
Harp seal.....................................  Western North Atlantic..........       7,813       6,819           2      54,673      47,692          12
Hooded seal...................................  Western North Atlantic..........         343         117           1       2,397         808           1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Zero (0) impacts indicate total less than 0.5 and a dash (-) is a true zero. In some cases where the estimated take within a cell is equal to 1,
  that value has been rounded up from a value that is less than 0.5 to avoid underestimating potential impacts to a species or stock based on the 7-year
  rounding rules discussed in Section 2.4 of Appendix E (Acoustic and Explosive Impacts Analysis) of the 2024 AFTT Draft Supplemental EIS/OEIS.


[[Page 19972]]


        Table 39--Annual and 7-Year Estimated Take of Marine Mammal Stocks From Sonar and Other Active Transducers During Navy Testing Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                    Maximum                 Maximum   Maximum 7-              Maximum 7-
                    Species                                   Stock                 annual      Maximum   annual AUD     year     Maximum 7-   year AUD
                                                                                  behavioral  annual TTS      INJ     behavioral   year TTS       INJ
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale....................  Western.........................          71         236           1         471       1,511           6
Blue whale....................................  Western North Atlantic..........           4          25           1          27         167           2
Bryde's whale.................................  Primary.........................           1           -           -           1           -           -
Fin whale.....................................  Western North Atlantic..........         328       1,010          12       2,128       6,469          76
Humpback whale................................  Gulf of Maine...................         127         353           5         836       2,227          33
Minke whale...................................  Canadian East Coast.............         401       1,575          37       2,631      10,399         253
Rice's whale..................................  Northern Gulf of America........          79         204           1         536       1,387           4
Sei whale.....................................  Nova Scotia.....................          75         305           4         489       2,003          27
Sperm whale...................................  North Atlantic..................       3,174       2,218           3      19,302      15,058          15
Sperm whale...................................  Northern Gulf of America........         214          21           -       1,281         116           -
Dwarf sperm whale.............................  Northern Gulf of America........          19         124           5         112         820          32
Pygmy sperm whale.............................  Northern Gulf of America........          20         106           4         122         693          23
Dwarf sperm whale.............................  Western North Atlantic..........         521       2,076         139       3,205      13,540         937
Pygmy sperm whale.............................  Western North Atlantic..........         525       2,095         132       3,226      13,665         892
Blainville's beaked whale.....................  Northern Gulf of America........         114           0           -         733           0           -
Goose-beaked whale............................  Northern Gulf of America........         417           1           -       2,679           1           -
Gervais' beaked whale.........................  Northern Gulf of America........         110           0           -         709           0           -
Blainville's beaked whale.....................  Western North Atlantic..........      10,331          98           0      65,116         672           0
Goose-beaked whale............................  Western North Atlantic..........      45,642         373           0     288,385       2,556           0
Gervais' beaked whale.........................  Western North Atlantic..........       9,485         191           -      60,788       1,306           -
Northern bottlenose whale.....................  Western North Atlantic..........         817           5           -       5,056          33           -
Sowerby's beaked whale........................  Western North Atlantic..........       9,570         198           -      61,349       1,351           -
True's beaked whale...........................  Western North Atlantic..........       9,488         194           -      60,825       1,324           -
Atlantic spotted dolphin......................  Northern Gulf of America........       6,523       5,425          18      42,782      35,096         113
Bottlenose dolphin............................  Gulf of America Eastern Coastal.          47           3           -         314          14           -
Bottlenose dolphin............................  Gulf of America Northern Coastal       4,346         503           -      30,370       3,519           -
Bottlenose dolphin............................  Gulf of America Oceanic.........       4,326       1,425           2      27,878       9,070           8
Bottlenose dolphin............................  Gulf of America Western Coastal.       1,412       1,125           -       8,760       6,977           -
Bottlenose dolphin............................  Mississippi Sound, Lake Borgne,          151          43           1         832         238           1
                                                 and Bay Boudreau.
Bottlenose dolphin............................  Northern Gulf of America              42,067      23,967          21     288,739     156,296         132
                                                 Continental Shelf.
Bottlenose dolphin............................  St. Andrew Bay..................          30           0           0         209           0           0
Bottlenose dolphin............................  St. Joseph Bay..................          35           -           -         240           -           -
Clymene dolphin...............................  Northern Gulf of America........         354         177           1       2,062       1,049           2
False killer whale............................  Northern Gulf of America........         152          52           0         936         325           0
Fraser's dolphin..............................  Northern Gulf of America........         150          66           0         911         417           0
Killer whale..................................  Northern Gulf of America........          76          21           0         470         128           0
Melon-headed whale............................  Northern Gulf of America........         525         163           1       3,233       1,008           1
Pygmy killer whale............................  Northern Gulf of America........         185          69           0       1,137         436           0
Risso's dolphin...............................  Northern Gulf of America........         138          40           0         857         238           0
Rough-toothed dolphin.........................  Northern Gulf of America........         888         612           1       5,852       4,008           3
Short-finned pilot whale......................  Northern Gulf of America........         574         357           2       3,391       2,176          12
Striped dolphin...............................  Northern Gulf of America........       1,541         580           0       9,961       3,725           0
Pantropical spotted dolphin...................  Northern Gulf of America........       4,088       1,495           2      25,521       9,358          12
Spinner dolphin...............................  Northern Gulf of America........         466         169           -       3,161       1,162           -
Atlantic white-sided dolphin..................  Western North Atlantic..........       5,106       2,547           4      32,124      16,876          24
Common dolphin................................  Western North Atlantic..........      52,543      50,344         100     334,319     321,736         634
Atlantic spotted dolphin......................  Western North Atlantic..........      16,870      29,186          56     101,954     186,189         381
Bottlenose dolphin............................  Indian River Lagoon Estuarine             17         137           0         119         955           0
                                                 System.
Bottlenose dolphin............................  Jacksonville Estuarine System...           5           7           0          30          39           0
Bottlenose dolphin............................  Northern North Carolina                  436         415           3       2,607       2,544          17
                                                 Estuarine System.
Bottlenose dolphin............................  Southern Georgia Estuarine                 1           -           -           1           -           -
                                                 System.
Tamanend's bottlenose dolphin.................  Western North Atlantic Central         1,377       1,403           0       8,277       8,253           0
                                                 Florida Coastal.
Tamanend's bottlenose dolphin.................  Western North Atlantic Northern        1,761       2,616           2      10,598      15,617           8
                                                 Florida Coastal.
Bottlenose dolphin............................  Western North Atlantic Northern        2,442       3,790          25      14,480      23,416         147
                                                 Migratory Coastal.
Bottlenose dolphin............................  Western North Atlantic Offshore.      28,717      37,950          69     176,788     249,785         470
Tamanend's bottlenose dolphin.................  Western North Atlantic South             239         841           2       1,483       4,817           8
                                                 Carolina/Georgia Coastal.
Bottlenose dolphin............................  Western North Atlantic Southern          269         734           1       1,664       4,137           6
                                                 Migratory Coastal.
Clymene dolphin...............................  Western North Atlantic..........      20,507      42,746          87     125,318     290,746         599
False killer whale............................  Western North Atlantic..........          80          84           1         495         554           1
Fraser's dolphin..............................  Western North Atlantic..........         359         638           1       2,249       4,345           6
Killer whale..................................  Western North Atlantic..........          30          37           1         180         252           1
Long-finned pilot whale.......................  Western North Atlantic..........       4,220       3,929           6      25,633      25,706          41
Melon-headed whale............................  Western North Atlantic..........         305         772           2       1,841       5,257          10
Pantropical spotted dolphin...................  Western North Atlantic..........         788       1,299           2       4,970       8,555          13
Pygmy killer whale............................  Western North Atlantic..........          30          77           0         186         525           0
Risso's dolphin...............................  Western North Atlantic..........       7,772       7,293          16      46,827      47,956         103
Rough-toothed dolphin.........................  Western North Atlantic..........         425         959           3       2,546       6,351          15
Short-finned pilot whale......................  Western North Atlantic..........       4,625       6,626          10      28,176      44,522          64
Spinner dolphin...............................  Western North Atlantic..........         410         757           1       2,487       5,047           7
Striped dolphin...............................  Western North Atlantic..........      37,593      49,900         134     218,185     330,534         918
White-beaked dolphin..........................  Western North Atlantic..........           7           5           -          44          32           -
Harbor porpoise...............................  Gulf of Maine/Bay of Fundy......      46,821       3,627          48     307,933      23,099         297
Gray seal.....................................  Western North Atlantic..........       4,438       3,318           8      29,334      20,924          48

[[Page 19973]]

 
Harbor seal...................................  Western North Atlantic..........       5,878       4,858          11      38,909      30,640          67
Harp seal.....................................  Western North Atlantic..........       8,808       2,327           2      56,816      15,303          11
Hooded seal...................................  Western North Atlantic..........         735         527           1       4,337       3,432           4
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Zero (0) impacts indicate total less than 0.5 and a dash (-) is a true zero. In some cases where the estimated take within a cell is equal to 1,
  that value has been rounded up from a value that is less than 0.5 to avoid underestimating potential impacts to a species or stock based on the 7-year
  rounding rules discussed in Section 2.4 of Appendix E (Acoustic and Explosive Impacts Analysis) of the 2024 AFTT Draft Supplemental EIS/OEIS.


    Table 40--Annual and 7-Year Estimated Take of Marine Mammal Stocks From Sonar and Other Active Transducers During Coast Guard Training Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                    Maximum                 Maximum   Maximum 7-              Maximum 7-
                    Species                                   Stock                 annual      Maximum   annual AUD     year     Maximum 7-   year AUD
                                                                                  behavioral  annual TTS      INJ     behavioral   year TTS       INJ
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale....................  Western.........................           1           -           -           4           -           -
Fin whale.....................................  Western North Atlantic..........           1           -           -           1           -           -
Humpback whale................................  Gulf of Maine...................           1           -           -           4           -           -
Minke whale...................................  Canadian East Coast.............           2           1           -          11           1           -
Rice's whale..................................  Northern Gulf of America........           1           -           -           1           -           -
Sei whale.....................................  Nova Scotia.....................           1           -           -           1           -           -
Sperm whale...................................  North Atlantic..................           5           -           -          35           -           -
Dwarf sperm whale.............................  Western North Atlantic..........           2           4           -          10          23           -
Pygmy sperm whale.............................  Western North Atlantic..........           2           2           -          10          11           -
Blainville's beaked whale.....................  Western North Atlantic..........           7           -           -          46           -           -
Goose-beaked whale............................  Western North Atlantic..........          40           -           -         275           -           -
Gervais' beaked whale.........................  Western North Atlantic..........           7           -           -          45           -           -
Sowerby's beaked whale........................  Western North Atlantic..........           6           -           -          37           -           -
True's beaked whale...........................  Western North Atlantic..........           6           -           -          39           -           -
Atlantic spotted dolphin......................  Northern Gulf of America........          35           -           -         239           -           -
Bottlenose dolphin............................  Gulf of America Oceanic.........           1           -           -           2           -           -
Bottlenose dolphin............................  Northern Gulf of America                  78           -           -         542           -           -
                                                 Continental Shelf.
Rough-toothed dolphin.........................  Northern Gulf of America........           4           -           -          22           -           -
Atlantic white-sided dolphin..................  Western North Atlantic..........           3           -           -          16           -           -
Common dolphin................................  Western North Atlantic..........          13           -           -          91           -           -
Atlantic spotted dolphin......................  Western North Atlantic..........          29           1           -         200           2           -
Bottlenose dolphin............................  Northern North Carolina                  489          11           -       3,423          71           -
                                                 Estuarine System.
Tamanend's bottlenose dolphin.................  Western North Atlantic Central             5           -           -          30           -           -
                                                 Florida Coastal.
Bottlenose dolphin............................  Western North Atlantic Northern        2,712          60           -      18,984         416           -
                                                 Migratory Coastal.
Bottlenose dolphin............................  Western North Atlantic Offshore.         103           1           -         716           1           -
Tamanend's bottlenose dolphin.................  Western North Atlantic South               1           -           -           1           -           -
                                                 Carolina/Georgia Coastal.
Bottlenose dolphin............................  Western North Atlantic Southern          294           3           -       2,056          20           -
                                                 Migratory Coastal.
Clymene dolphin...............................  Western North Atlantic..........           1           -           -           1           -           -
False killer whale............................  Western North Atlantic..........           1           -           -           1           -           -
Fraser's dolphin..............................  Western North Atlantic..........           1           -           -           7           -           -
Killer whale..................................  Western North Atlantic..........           1           -           -           1           -           -
Melon-headed whale............................  Western North Atlantic..........           3           -           -          19           -           -
Pantropical spotted dolphin...................  Western North Atlantic..........           5           -           -          29           -           -
Pygmy killer whale............................  Western North Atlantic..........           1           -           -           2           -           -
Risso's dolphin...............................  Western North Atlantic..........           6           -           -          41           -           -
Rough-toothed dolphin.........................  Western North Atlantic..........           2           -           -          14           -           -
Short-finned pilot whale......................  Western North Atlantic..........          13           0           -          91           0           -
Spinner dolphin...............................  Western North Atlantic..........           3           -           -          15           -           -
Harbor porpoise...............................  Gulf of Maine/Bay of Fundy......          46           6           -         321          40           -
Gray seal.....................................  Western North Atlantic..........          46           1           -         322           7           -
Harbor seal...................................  Western North Atlantic..........          68           2           -         474           8           -
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Zero (0) impacts indicate total less than 0.5 and a dash (-) is a true zero. In some cases where the estimated take within a cell is equal to 1,
  that value has been rounded up from a value that is less than 0.5 to avoid underestimating potential impacts to a species or stock based on the 7-year
  rounding rules discussed in Section 2.4 of Appendix E (Acoustic and Explosive Impacts Analysis) of the 2024 AFTT Draft Supplemental EIS/OEIS.

Estimated Take From Air Guns and Pile Driving
    Table 41 provides estimated effects from air guns, including the 
comparative amounts of TTS and behavioral disturbance for each species 
and stock annually, noting that if a modeled marine mammal was 
``taken'' through exposure to both TTS and behavioral disturbance in 
the model, it was recorded as a TTS.

[[Page 19974]]



                     Table 41--Annual and 7-Year Estimated Take of Marine Mammal Stocks From Air Guns During Navy Testing Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                              Maximum                   Maximum     Maximum 7-                Maximum 7-
                  Species                                Stock                 annual      Maximum     annual AUD      year      Maximum 7-    year AUD
                                                                             behavioral   annual TTS      INJ       behavioral    year TTS       INJ
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fin whale..................................  Western North Atlantic.......            1            -            -            1            -            -
Dwarf sperm whale..........................  Northern Gulf of America.....            1            -            -            1            -            -
Dwarf sperm whale..........................  Western North Atlantic.......            1            1            0            3            2            0
Pygmy sperm whale..........................  Western North Atlantic.......            1            1            -            2            4            -
Bottlenose dolphin.........................  Northern Gulf of America                 1            0            -            1            0            -
                                              Continental Shelf.
Common dolphin.............................  Western North Atlantic.......            1            -            -            4            -            -
Bottlenose dolphin.........................  Western North Atlantic                   1            -            -            1            -            -
                                              Offshore.
Striped dolphin............................  Western North Atlantic.......            1            -            -            2            -            -
Harbor porpoise............................  Gulf of Maine/Bay of Fundy...            2            3            1           12           15            1
Gray seal..................................  Western North Atlantic.......            1            0            -            7            0            -
Harbor seal................................  Western North Atlantic.......            1            0            -            5            0            -
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Zero (0) impacts indicate total less than 0.5 and a dash (-) is a true zero. In some cases where the estimated take within a cell is equal to 1,
  that value has been rounded up from a value that is less than 0.5 to avoid underestimating potential impacts to a species or stock based on the 7-year
  rounding rules discussed in Section 2.4 of Appendix E (Acoustic and Explosive Impacts Analysis) of the 2024 AFTT Draft Supplemental EIS/OEIS.

    Table 42 provides the estimated effects from pile driving and 
extraction, including the comparative amounts of TTS and behavioral 
disturbance for each species and stock annually, noting that if a 
modeled marine mammal was ``taken'' through exposure to both TTS and 
behavioral disturbance in the model, it was recorded as a TTS.

                  Table 42--Annual and 7-Year Estimated Take of Marine Mammal Stocks From Pile Driving During Navy Training Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                              Maximum                   Maximum     Maximum 7-                Maximum 7-
                  Species                                Stock                 annual      Maximum     annual AUD      year      Maximum 7-    year AUD
                                                                             behavioral   annual TTS      INJ       behavioral    year TTS       INJ
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bottlenose dolphin.........................  Gulf of America Northern             1,894            0            -       13,255            0            -
                                              Coastal.
Bottlenose dolphin.........................  Mississippi Sound, Lake              1,564            0            -       10,944            0            -
                                              Borgne, and Bay Boudreau.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Zero (0) impacts indicate total less than 0.5 and a dash (-) is a true zero.

Estimated Take From Explosives
    Table 43 provides estimated effects from explosives during Navy 
training activities and table 44 provides estimated effects from 
explosives including small ship shock trials from Navy testing 
activities. Table 45 provides estimated effects from small ship shock 
trials over a maximum year (two events) of Navy testing activities, 
which is a subset of the information included in table 44. Table 46 
provides estimated effects from explosives during Coast Guard training 
activities.

[[Page 19975]]



                                       Table 43--Annual and 7-Year Estimated Take of Marine Mammal Stocks From Explosives During Navy Training Activities
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                   Maximum                                                   Maximum
                                                                                 Maximum     Maximum    Maximum     annual    Maximum    Maximum  7-   Maximum    Maximum     7-year    Maximum
                   Species                                 Stock                 annual       annual     annual      non-      annual       year        7-year     7-year      non-      7-year
                                                                               behavioral      TTS      AUD INJ    auditory  mortality   behavioral      TTS      AUD INJ    auditory  mortality
                                                                                                                    injury                                                    injury
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale..................  Western.......................            14         10          0          -          -            93         66          0          -          -
Blue whale..................................  Western North Atlantic........             1          1          -          -          -             2          1          -          -          -
Fin whale...................................  Western North Atlantic........            30          8          0          -          -           205         50          0          -          -
Humpback whale..............................  Gulf of Maine.................            14          7          1          -          -            94         43          1          -          -
Minke whale.................................  Canadian East Coast...........            24         11          1          -          -           167         73          7          -          -
Rice's whale................................  Northern Gulf of America......             0          1          -          -          -             0          1          -          -          -
Sei whale...................................  Nova Scotia...................             4          1          0          -          -            27          3          0          -          -
Sperm whale.................................  North Atlantic................             4          6          1          1          -            26         36          3          1          -
Sperm whale.................................  Northern Gulf of America......             1          1          0          -          -             1          1          0          -          -
Dwarf sperm whale...........................  Northern Gulf of America......             2          2          1          0          -             8         10          1          0          -
Pygmy sperm whale...........................  Northern Gulf of America......             2          2          1          -          -             9         12          1          -          -
Dwarf sperm whale...........................  Western North Atlantic........            27         33          7          -          -           188        227         47          -          -
Pygmy sperm whale...........................  Western North Atlantic........            26         33          9          -          -           182        225         60          -          -
Blainville's beaked whale...................  Western North Atlantic........             1          2          1          -          -             5          8          1          -          -
Goose-beaked whale..........................  Western North Atlantic........             6          4          1          -          -            36         28          3          -          -
Gervais' beaked whale.......................  Western North Atlantic........             1          1          -          -          -             1          3          -          -          -
Sowerby's beaked whale......................  Western North Atlantic........             1          1          0          -          -             7          5          0          -          -
True's beaked whale.........................  Western North Atlantic........             1          1          0          -          -             1          1          0          -          -
Atlantic spotted dolphin....................  Northern Gulf of America......             1          3          1          0          -             4         19          4          0          -
Bottlenose dolphin..........................  Gulf of America Eastern                    1          1          -          -          -             4          7          -          -          -
                                               Coastal.
Bottlenose dolphin..........................  Gulf of America Northern                   1          2          1          -          -             3          8          2          -          -
                                               Coastal.
Bottlenose dolphin..........................  Gulf of America Oceanic.......             1          1          0          -          -             3          4          0          -          -
Bottlenose dolphin..........................  Northern Gulf of America                  14         19          2          1          0            95        132         12          1          0
                                               Continental Shelf.
Fraser's dolphin............................  Northern Gulf of America......             1          1          0          -          -             1          1          0          -          -
Rough-toothed dolphin.......................  Northern Gulf of America......             1          1          0          -          -             1          3          0          -          -
Short-finned pilot whale....................  Northern Gulf of America......             0          1          -          -          -             0          3          -          -          -
Striped dolphin.............................  Northern Gulf of America......             0          1          1          0          -             0          2          1          0          -
Pantropical spotted dolphin.................  Northern Gulf of America......             1          1          1          1          0             5          7          2          2          0
Atlantic white-sided dolphin................  Western North Atlantic........             4          6          1          1          -            26         41          7          3          -
Common dolphin..............................  Western North Atlantic........            50         42          5          1          -           345        288         29          4          -
Atlantic spotted dolphin....................  Western North Atlantic........            35         37          4          1          0           245        257         23          5          0
Bottlenose dolphin..........................  Northern North Carolina                    1          -          -          -          -             1          -          -          -          -
                                               Estuarine System.
Bottlenose dolphin..........................  Southern North Carolina                    1          -          -          -          -             1          -          -          -          -
                                               Estuarine System.
Tamanend's bottlenose dolphin...............  Western North Atlantic Central            10          8          1          1          -            65         53          4          2          -
                                               Florida Coastal.
Tamanend's bottlenose dolphin...............  Western North Atlantic                     2          3          1          0          -             8         17          1          0          -
                                               Northern Florida Coastal.
Bottlenose dolphin..........................  Western North Atlantic                    21         41          5          1          0           147        283         30          1          0
                                               Northern Migratory Coastal.
Bottlenose dolphin..........................  Western North Atlantic                    50         53          6          1          1           347        365         39          3          1
                                               Offshore.
Tamanend's bottlenose dolphin...............  Western North Atlantic South               5          5          1          0          1            32         35          3          0          1
                                               Carolina/Georgia Coastal.
Bottlenose dolphin..........................  Western North Atlantic                    19         29          4          1          0           133        202         26          4          0
                                               Southern Migratory Coastal.
Clymene dolphin.............................  Western North Atlantic........            16         21          6          1          1           112        141         37          3          3
Fraser's dolphin............................  Western North Atlantic........             1          1          1          0          -             4          2          2          0          -
Long-finned pilot whale.....................  Western North Atlantic........             4          3          2          1          -            28         21          9          1          -
Pantropical spotted dolphin.................  Western North Atlantic........             2          1          1          0          0             8          6          1          0          0
Pygmy killer whale..........................  Western North Atlantic........             0          -          1          0          -             0          -          1          0          -
Risso's dolphin.............................  Western North Atlantic........             4          5          1          1          0            28         32          2          1          0
Rough-toothed dolphin.......................  Western North Atlantic........             2          2          1          0          -             8          9          1          0          -
Short-finned pilot whale....................  Western North Atlantic........             7          5          1          0          0            45         32          7          0          0
Spinner dolphin.............................  Western North Atlantic........             0          1          0          -          -             0          5          0          -          -
Striped dolphin.............................  Western North Atlantic........            11         13          3          1          0            77         87         20          5          0
Harbor porpoise.............................  Gulf of Maine/Bay of Fundy....            74        235         67          0          -           515      1,644        464          0          -
Gray seal...................................  Western North Atlantic........            46         44          3          0          -           322        304         20          0          -
Harbor seal.................................  Western North Atlantic........            72         67          4          0          -           499        468         28          0          -
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Zero (0) impacts indicate total less than 0.5 and a dash (-) is a true zero. In some cases where the estimated take within a cell is equal to 1, that value has been rounded up from a
  value that is less than 0.5 to avoid underestimating potential impacts to a species or stock based on the 7-year rounding rules discussed in Section 2.4 of Appendix E (Acoustic and Explosive
  Impacts Analysis) of the 2024 AFTT Draft Supplemental EIS/OEIS.


[[Page 19976]]


                                       Table 44--Annual and 7-Year Estimated Take of Marine Mammal Stocks From Explosives During Navy Training Activities
                                                                               [Includes small ship shock trials]
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                   Maximum                                                   Maximum
                                                                                 Maximum     Maximum    Maximum     annual    Maximum    Maximum  7-   Maximum    Maximum     7-year    Maximum
                   Species                                 Stock                 annual       annual     annual      non-      annual       year        7-year     7-year      non-      7-year
                                                                               behavioral      TTS      AUD INJ    auditory  mortality   behavioral      TTS      AUD INJ    auditory  mortality
                                                                                                                    injury                                                    injury
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale..................  Western.......................             6          3          0          -          -            34         20          0          -          -
Blue whale..................................  Western North Atlantic........             1          1          -          -          -             2          3          -          -          -
Fin whale...................................  Western North Atlantic........           110         75          3          -          -           670        442         17          -          -
Humpback whale..............................  Gulf of Maine.................            13          7          0          -          -            81         42          0          -          -
Minke whale.................................  Canadian East Coast...........            26         30          1          -          -           162        124          4          -          -
Rice's whale................................  Northern Gulf of America......             7          4          1          -          -            49         25          1          -          -
Sei whale...................................  Nova Scotia...................             6          3          0          -          -            40         17          0          -          -
Sperm whale.................................  North Atlantic................             2          1          1          -          -             8          5          1          -          -
Sperm whale.................................  Northern Gulf of America......             1          1          0          0          0             1          1          0          0          0
Dwarf sperm whale...........................  Northern Gulf of America......             2         27         16          -          -            12         78         40          -          -
Dwarf sperm whale...........................  Western North Atlantic........            13         28          8          0          0            82        119         25          0          0
Pygmy sperm whale...........................  Northern Gulf of America......             3         29         16          -          -            17         87         40          -          -
Pygmy sperm whale...........................  Western North Atlantic........            12         29          9          0          -            73        126         33          0          -
Blainville's beaked whale...................  Western North Atlantic........             1          1          0          0          -             1          1          0          0          -
Goose-beaked whale..........................  Northern Gulf of America......             0          1          0          -          -             0          1          0          -          -
Gervais' beaked whale.......................  Northern Gulf of America......             0          1          -          -          -             0          1          -          -          -
Goose-beaked whale..........................  Western North Atlantic........             1          1          1          0          0             7          6          2          0          0
Gervais' beaked whale.......................  Western North Atlantic........             1          1          1          -          -             1          1          1          -          -
Northern bottlenose whale...................  Western North Atlantic........             1          0          1          -          -             1          0          1          -          -
Sowerby's beaked whale......................  Western North Atlantic........             1          1          1          -          -             1          4          1          -          -
True's beaked whale.........................  Western North Atlantic........             1          1          0          -          -             1          1          0          -          -
Atlantic spotted dolphin....................  Northern Gulf of America......            17         11          1          0          0           119         74          6          0          0
Bottlenose dolphin..........................  Gulf of America Eastern                    -          1          0          -          -             -          1          0          -          -
                                               Coastal.
Bottlenose dolphin..........................  Gulf of America Northern                  86        117         16          -          -           601        815        112          -          -
                                               Coastal.
Bottlenose dolphin..........................  Gulf of America Oceanic.......             3          1          1          0          0            15          7          2          0          0
Bottlenose dolphin..........................  Gulf of America Western                    2          1          1          0          -            10          4          1          0          -
                                               Coastal.
Bottlenose dolphin..........................  Northern Gulf of America                 369        177          3          1          0         2,577      1,234         18          1          0
                                               Continental Shelf.
Bottlenose dolphin..........................  St. Andrew Bay................             1          1          -          -          -             1          1          -          -          -
Clymene dolphin.............................  Northern Gulf of America......             1          1          1          1          0             4          3          1          1          0
False killer whale..........................  Northern Gulf of America......             1          1          0          -          -             1          1          0          -          -
Fraser's dolphin............................  Northern Gulf of America......             0          0          0          0          -             0          0          0          0          -
Melon-headed whale..........................  Northern Gulf of America......             1          1          0          0          0             1          3          0          0          0
Pygmy killer whale..........................  Northern Gulf of America......             1          1          0          0          0             1          1          0          0          0
Risso's dolphin.............................  Northern Gulf of America......             1          1          0          0          0             1          1          0          0          0
Rough-toothed dolphin.......................  Northern Gulf of America......             6          4          1          1          0            39         21          1          1          0
Short-finned pilot whale....................  Northern Gulf of America......             1          1          1          0          0             3          2          1          0          0
Striped dolphin.............................  Northern Gulf of America......             1         10          4          2          1             5         27          9          5          2
Pantropical spotted dolphin.................  Northern Gulf of America......             2         11          2          2          2            13         31          5          6          5
Spinner dolphin.............................  Northern Gulf of America......             0          1          0          0          -             0          1          0          0          -
Atlantic white-sided dolphin................  Western North Atlantic........             6          3          1          0          0            37         15          1          0          0
Common dolphin..............................  Western North Atlantic........           384        251         20          1          0         2,320      1,497        118          1          0
Atlantic spotted dolphin....................  Western North Atlantic........            39         22          3          1          0           221        119         16          1          0
Tamanend's bottlenose dolphin...............  Western North Atlantic Central            12          5          1          0          0            67         29          4          0          0
                                               Florida Coastal.
Tamanend's bottlenose dolphin...............  Western North Atlantic                     4          1          1          -          -            21          7          1          -          -
                                               Northern Florida Coastal.
Bottlenose dolphin..........................  Western North Atlantic                     2          2          1          -          -            10         11          1          -          -
                                               Northern Migratory Coastal.
Bottlenose dolphin..........................  Western North Atlantic                    67         54          6          1          1           396        300         31          3          1
                                               Offshore.
Tamanend's bottlenose dolphin...............  Western North Atlantic South               9          3          1          0          0            55         17          3          0          0
                                               Carolina/Georgia Coastal.
Bottlenose dolphin..........................  Western North Atlantic                     9          3          1          0          -            55         18          2          0          -
                                               Southern Migratory Coastal.
Clymene dolphin.............................  Western North Atlantic........             5          4          1          1          0            30         24          4          1          0
False killer whale..........................  Western North Atlantic........             -          1          -          -          -             -          1          -          -          -
Fraser's dolphin............................  Western North Atlantic........             1          2          0          0          -             3          5          0          0          -
Killer whale................................  Western North Atlantic........             1          1          0          -          0             2          1          0          -          0
Long-finned pilot whale.....................  Western North Atlantic........            18         10          1          0          0           108         60          4          0          0
Melon-headed whale..........................  Western North Atlantic........             1          0          0          0          0             1          0          0          0          0

[[Page 19977]]

 
Pantropical spotted dolphin.................  Western North Atlantic........             0          0          0          0          0             0          0          0          0          0
Pygmy killer whale..........................  Western North Atlantic........             0          1          0          -          -             0          1          0          -          -
Risso's dolphin.............................  Western North Atlantic........            18         20          3          1          0           116        105         15          1          0
Rough-toothed dolphin.......................  Western North Atlantic........             1          1          0          0          -             2          2          0          0          -
Short-finned pilot whale....................  Western North Atlantic........            13         11          2          0          0            78         58          9          0          0
Spinner dolphin.............................  Western North Atlantic........             1          0          0          0          -             2          0          0          0          -
Striped dolphin.............................  Western North Atlantic........            17         10          2          1          0           109         64         12          1          0
Harbor porpoise.............................  Gulf of Maine/Bay of Fundy....            75         97         21          0          0           493        604        123          0          0
Gray seal...................................  Western North Atlantic........            38         18          2          0          -           262        118         10          0          -
Harbor seal.................................  Western North Atlantic........            54         22          2          0          0           370        148         11          0          0
Harp seal...................................  Western North Atlantic........            13          8          1          0          -            88         50          4          0          -
Hooded seal.................................  Western North Atlantic........             1          1          0          -          -             4          4          0          -          -
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Zero (0) impacts indicate total less than 0.5 and a dash (-) is a true zero. In some cases where the estimated take within a cell is equal to 1, that value has been rounded up from a
  value that is less than 0.5 to avoid underestimating potential impacts to a species or stock based on the 7-year rounding rules discussed in Section 2.4 of Appendix E (Acoustic and Explosive
  Impacts Analysis) of the 2024 AFTT Draft Supplemental EIS/OEIS.


[[Page 19978]]


 Table 45--Annual Estimated Effects to Marine Mammal Stocks From Small Ship Shock Trials Over a Maximum Year of
                                                  Navy Testing
                                                  [Two events]
----------------------------------------------------------------------------------------------------------------
                                                                                          Maximum
                                                                Maximum     Maximum    annual  non-     Maximum
               Species                         Stock            annual      annual       auditory       annual
                                                                  TTS       AUD INJ       injury       mortality
----------------------------------------------------------------------------------------------------------------
North Atlantic right whale..........  Western...............           1           -               -           -
Blue whale..........................  Western North Atlantic           1           -               -           -
Fin whale...........................  Western North Atlantic           2           0               -           -
Humpback whale......................  Gulf of Maine.........           1           -               -           -
Minke whale.........................  Canadian East Coast...          17           1               -           -
Sei whale...........................  Nova Scotia...........           1           0               -           -
Dwarf sperm whale...................  Northern Gulf of                24          15               -           -
                                       America.
Pygmy sperm whale...................  Northern Gulf of                26          15               -           -
                                       America.
Dwarf sperm whale...................  Western North Atlantic          14           5               -           -
Pygmy sperm whale...................  Western North Atlantic          14           6               -           -
Goose-beaked whale..................  Northern Gulf of                 1           0               -           -
                                       America.
Gervais' beaked whale...............  Northern Gulf of                 1           -               -           -
                                       America.
Melon-headed whale..................  Northern Gulf of                 1           0               0           0
                                       America.
Pantropical spotted dolphin.........  Northern Gulf of                 9           1               2           2
                                       America.
Rough-toothed dolphin...............  Northern Gulf of                 1           0               1           0
                                       America.
Short-finned pilot whale............  Northern Gulf of                 1           1               0           0
                                       America.
Striped dolphin.....................  Northern Gulf of                10           3               2           1
                                       America.
Atlantic spotted dolphin............  Western North Atlantic           1           -               1           -
Bottlenose dolphin..................  Western North Atlantic           5           1               1           1
                                       Offshore.
Fraser's dolphin....................  Western North Atlantic           2           0               0           -
Pygmy killer whale..................  Western North Atlantic           1           -               -           -
Risso's dolphin.....................  Western North Atlantic           4           1               1           0
Rough-toothed dolphin...............  Western North Atlantic           1           -               0           -
Short-finned pilot whale............  Western North Atlantic           1           1               0           0
----------------------------------------------------------------------------------------------------------------
Note: Zero (0) impacts indicate total less than 0.5 and a dash (-) is a true zero. In some cases where the
  estimated take within a cell is equal to 1, that value has been rounded up from a value that is less than 0.5
  to avoid underestimating potential impacts to a species or stock based on the 7-year rounding rules discussed
  in Section 2.4 of Appendix E (Acoustic and Explosive Impacts Analysis) of the 2024 AFTT Draft Supplemental EIS/
  OEIS.


[[Page 19979]]


                                    Table 46--Annual and 7-Year Estimated Take of Marine Mammal Stocks From Explosives During Coast Guard Training Activities
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                   Maximum                                                   Maximum
                                                                                 Maximum     Maximum    Maximum     annual    Maximum    Maximum  7-   Maximum    Maximum     7-year    Maximum
                   Species                                 Stock                 annual       annual     annual      non-      annual       year        7-year     7-year      non-      7-year
                                                                               behavioral      TTS      AUD INJ    auditory  mortality   behavioral      TTS      AUD INJ    auditory  mortality
                                                                                                                    injury                                                    injury
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Fin whale...................................  Western North Atlantic........             1          1          0          -          -             1          1          0          -          -
Humpback whale..............................  Gulf of Maine.................             1          1          0          -          -             2          1          0          -          -
Minke whale.................................  Canadian East Coast...........             1          1          0          -          -             1          1          0          -          -
Sei whale...................................  Nova Scotia...................             1          0          -          -          -             1          0          -          -          -
Sperm whale.................................  North Atlantic................             1          0          -          -          -             1          0          -          -          -
Dwarf sperm whale...........................  Northern Gulf of America......             1          1          -          -          -             1          1          -          -          -
Pygmy sperm whale...........................  Northern Gulf of America......             1          1          -          -          -             1          1          -          -          -
Dwarf sperm whale...........................  Western North Atlantic........             1          1          1          -          -             7          5          1          -          -
Pygmy sperm whale...........................  Western North Atlantic........             1          1          1          -          -             5          5          1          -          -
Goose-beaked whale..........................  Western North Atlantic........             1          1          -          -          -             1          1          -          -          -
Atlantic spotted dolphin....................  Northern Gulf of America......             1          0          -          -          -             2          0          -          -          -
Bottlenose dolphin..........................  Gulf of America Oceanic.......             1          0          -          -          -             1          0          -          -          -
Bottlenose dolphin..........................  Northern Gulf of America                   4          3          1          -          -            25         18          1          -          -
                                               Continental Shelf.
Atlantic white-sided dolphin................  Western North Atlantic........             2          1          0          -          -             8          3          0          -          -
Common dolphin..............................  Western North Atlantic........             3          3          1          -          -            21         15          1          -          -
Atlantic spotted dolphin....................  Western North Atlantic........             1          1          -          -          -             2          1          -          -          -
Bottlenose dolphin..........................  Western North Atlantic                     1          1          -          0          -             4          2          -          0          -
                                               Offshore.
Long-finned pilot whale.....................  Western North Atlantic........             1          1          0          -          -             2          1          0          -          -
Risso's dolphin.............................  Western North Atlantic........             1          1          0          -          -             1          1          0          -          -
Short-finned pilot whale....................  Western North Atlantic........             1          1          0          -          -             1          1          0          -          -
Striped dolphin.............................  Western North Atlantic........             1          1          0          -          -             3          1          0          -          -
Harbor porpoise.............................  Gulf of Maine/Bay of Fundy....            22         24          4          -          -           150        166         28          -          -
Gray seal...................................  Western North Atlantic........             1          1          0          -          -             7          6          0          -          -
Harbor seal.................................  Western North Atlantic........             2          2          1          -          -            10          8          1          -          -
Harp seal...................................  Western North Atlantic........             2          2          1          -          -            14         13          1          -          -
Hooded seal.................................  Western North Atlantic........             1          1          0          -          -             2          1          0          -          -
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Zero (0) impacts indicate total less than 0.5 and a dash (-) is a true zero. In some cases where the estimated take within a cell is equal to 1, that value has been rounded up from a
  value that is less than 0.5 to avoid underestimating potential impacts to a species or stock based on the 7-year rounding rules discussed in Section 2.4 of Appendix E (Acoustic and Explosive
  Impacts Analysis) of the 2024 AFTT Draft Supplemental EIS/OEIS.


[[Page 19980]]

Estimated Take From Vessel Strike by Serious Injury or Mortality

    Vessel strikes from commercial, recreational, and military vessels 
are known to affect large whales and have resulted in serious injury 
and fatalities to cetaceans (Abramson et al., 2011; Berman-Kowalewski 
et al., 2010a; Calambokidis, 2012; Douglas et al., 2008; Laggner, 2009; 
Lammers et al., 2003; Van der Hoop et al., 2013; Van der Hoop et al., 
2012). Records of vessel strikes of large whales date back to the early 
17th century, and the worldwide number of vessel strikes of large 
whales appears to have increased steadily during recent decades (Laist 
et al., 2001; Ritter 2012).
    Numerous studies of interactions between surface vessels and marine 
mammals have demonstrated that free-ranging marine mammals often, but 
not always (e.g., McKenna et al., 2015), engage in avoidance behavior 
when surface vessels move toward them. It is not clear whether these 
responses are caused by the physical presence of a surface vessel, the 
underwater noise generated by the vessel, or an interaction between the 
two (Amaral and Carlson, 2005; Au and Green, 2000; Bain et al., 2006; 
Bauer 1986; Bejder et al., 1999; Bejder and Lusseau, 2008; Bejder et 
al., 2009; Bryant et al., 1984; Corkeron, 1995; Erbe, 2002; 
F[eacute]lix, 2001; Goodwin and Cotton, 2004; Greig et al., 2020; 
Guilpin et al., 2020; Keen et al., 2019; Lemon et al., 2006; Lusseau, 
2003; Lusseau, 2006; Magalhaes et al., 2002; Nowacek et al., 2001; 
Redfern et al., 2020; Richter et al., 2003; Scheidat et al., 2004; 
Simmonds, 2005; Szesciorka et al., 2019; Watkins, 1986; Williams et 
al., 2002; Wursig et al., 1998). Several authors suggest that the noise 
generated during motion is probably an important factor (Blane and 
Jaakson, 1994; Evans et al., 1992; Evans et al., 1994). These studies 
suggest that the behavioral responses of marine mammals to surface 
vessels are similar to their behavioral responses to predators. 
Avoidance behavior is expected to be even stronger in the subset of 
instances during which the Action Proponents are conducting military 
readiness activities using active sonar or explosives.
    The marine mammals most vulnerable to vessel strikes are those that 
spend extended periods of time at the surface in order to restore 
oxygen levels within their tissues after deep dives (e.g., sperm 
whales). In addition, some baleen whales seem generally unresponsive to 
vessel sound, making them more susceptible to vessel strikes (Nowacek 
et al., 2004). These species are primarily large, slow moving whales. 
There are nine species (15 stocks) of large whales that are known to 
occur within the AFTT Study Area (table 14): blue whale, Bryde's whale, 
fin whale, humpback whale, minke whale, NARW, Rice's whale, sei whale, 
and sperm whale.
    Some researchers have suggested the relative risk of a vessel 
strike can be assessed as a function of animal density and the 
magnitude of vessel traffic (e.g., Fonnesbeck et al., 2008; Vanderlaan 
et al., 2008). Differences among vessel types also influence the 
probability of a vessel strike. The ability of any vessel to detect a 
marine mammal and avoid a collision depends on a variety of factors, 
including environmental conditions, vessel design, size, speed, and 
ability and number of personnel observing, as well as the behavior of 
the animal. Vessel speed, size, and mass are all important factors in 
determining if injury or death of a marine mammal is likely due to a 
vessel strike. For large vessels, speed and angle of approach can 
influence the severity of a strike. Large whales also do not have to be 
at the water's surface to be struck. Silber et al. (2010) found that 
when a whale is below the surface (about one to two times the vessel 
draft), under certain circumstances (vessel speed and location of the 
whale relative to the ship's centerline), there is likely to be a 
pronounced propeller suction effect. This suction effect may draw the 
whale into the hull of the ship, increasing the probability of 
propeller strikes.
    There are some key differences between the operation of military 
and non-military vessels which make the likelihood of a military vessel 
striking a whale lower than some other vessels (e.g., commercial 
merchant vessels). Key differences include:
     Military vessels have personnel assigned to stand watch at 
all times, day and night, when moving through the water (i.e., when the 
vessel is underway). Watch personnel undertake extensive training and 
are certified to stand watch only after demonstrating competency in all 
necessary skills. While on watch, personnel employ visual search and 
reporting procedures in accordance with the U.S. Navy Lookout Training 
Handbook, the Coast Guard's Shipboard Lookout Manual, or civilian 
equivalent.
     The bridges of many military vessels are positioned closer 
to the bow, offering better visibility ahead of the vessel (compared to 
a commercial merchant vessel);
     Military readiness activities often involve aircraft 
(which can serve as part of the Lookout team), that can more readily 
detect cetaceans in the vicinity of a vessel or ahead of a vessel's 
present course, often before crew on the vessel would be able to detect 
them;
     Military vessels are generally more maneuverable than 
commercial merchant vessels, and are therefore capable of changing 
course more quickly in the event cetaceans are spotted in the vessel's 
path;
     Military vessels operate at the slowest speed practical 
consistent with operational requirements. While minimum speed is 
intended as a fuel conservation measure particular to a certain ship 
class, secondary benefits include a better ability to detect and avoid 
objects in the water, including marine mammals;
     Military ships often operate within a defined area for a 
period of time, in contrast to point-to-point commercial shipping over 
greater distances;
     The crew size on military vessels is generally larger than 
merchant vessels, allowing for stationing more trained Lookouts on the 
bridge. At all times when the Action Proponents' vessels are underway, 
trained Lookouts and bridge navigation teams are used to detect objects 
on the surface of the water ahead of the ship, including cetaceans. 
Some events may have additional personnel (beyond the minimum number of 
required Lookouts) who are already standing watch in or on the platform 
conducting the event or additional participating platforms and would 
have eyes on the water for all or part of an event. These additional 
personnel serve as members of the Lookout team; and
     When submerged, submarines are generally slow moving (to 
avoid detection); as a result, marine mammals at depth with a submarine 
are likely able to avoid collision with the submarine. When a submarine 
is transiting on the surface, the Navy posts Lookouts serving the same 
function as they do on surface vessels.
    Vessel strike to marine mammals is not associated with any specific 
military readiness activity. Rather, vessel strike is a limited and 
sporadic, but possible, accidental result of military vessel movement 
within the AFTT Study Area or while in transit.
    Prior to 2009, there is limited information on vessel strikes from 
military readiness activities in the AFTT Study Area. One known 
incident of vessel strike in the AFTT Study Area occurred in 2001, when 
a 505 ft (154 m) Navy vessel struck and killed a sperm whale 20 mi 
(32.2 km) south of Puerto Rico (Jensen and Silber, 2004). (Of note, at 
the time of the strike, the Navy still used the Vieques Naval Training 
Range; activities in this area ceased in 2003, and since then, vessel 
traffic has significantly decreased, and there are

[[Page 19981]]

currently no plans to increase activity in that area.) A second known 
incident of vessel strike occurred in VACAPES on May 15, 2005, when a 
Navy vessel was involved in a strike with ``reasonable potential'' to 
have been a sperm whale.
    Since 2009, there have been six recorded vessel strikes of large 
whales by the Action Proponents in the AFTT Study Area: three by the 
Navy and three by the Coast Guard. The Navy struck one whale in 2011 
(species unknown), two whales in 2012 (species unknown), and has not 
struck a large whale in the AFTT Study Area since 2012. All strikes 
during this timeframe occurred in the VACAPES OPAREA: one strike in the 
VACAPES Range Complex in 2011, one strike in the VACAPES Range Complex 
in 2012, and one strike in the Lower Chesapeake Bay in 2012. The Coast 
Guard struck two whales in 2009 (both reported as NARW), and one whale 
in May 2024 (species unknown). On December 14, 2009, an 87 ft (26.5 m) 
Coast Guard patrol boat traveling at a speed of 9.2 kn (17 km/hr) 
struck two whales (reported as NARW) at the same time near Cape Henry, 
Virginia, and observed the animals swimming away without apparent 
injuries, though it is important to note that not all injuries are 
evident when a whale is struck and the fate of these two NARW is 
unknown. It is also important to note that not all whale strikes result 
in mortality, however, given the potential for non-visible injuries, 
NMFS conservatively assumes that these strikes resulted in mortality of 
both whales.
    In light of the key differences between the operation of military 
and non-military vessels discussed above, it is highly unlikely that a 
military vessel would strike any type of marine mammal without 
detecting it. Specifically, Lookouts posted on or near the ship's bow 
can visually detect a strike in the absence of other indications that a 
strike has occurred. The Action Proponents' internal procedures and 
mitigation requirements include reporting of any vessel strikes of 
marine mammals, and the Action Proponents' discipline, extensive 
training (not only for detecting marine mammals, but for detecting and 
reporting any potential navigational obstruction), and strict chain of 
command give NMFS a high level of confidence that all strikes are 
reported. Accordingly, NMFS is confident that the Navy and Coast 
Guard's reported strikes are accurate and appropriate for use in the 
analysis.
    When generally compared to mysticetes, odontocetes are more capable 
of physically avoiding a vessel strike and since some species occur in 
large groups, they are more easily seen when they are closer to the 
water surface. The smaller size and maneuverability of dolphins, small 
whales (not including large whale calves), porpoises, and pinnipeds 
generally make vessel strike very unlikely. For as long as records have 
been kept, neither the Navy nor the Coast Guard have any record of any 
small whales or pinnipeds being struck by a vessel as a result of 
military readiness activities. Over the same time period, NMFS, the 
Navy, and the Coast Guard have only one record of a dolphin being 
struck by a vessel as a result of Navy or Coast Guard activities. The 
dolphin was accidentally struck by a Navy small boat in fall 2021 in 
Saint Andrew's Pass, Florida. Other than this one reported strike of a 
dolphin in 2021, NMFS has never received any reports from other LOA or 
Incidental Harassment Authorization holders indicating that these 
species have been struck by vessels. Worldwide vessel strike records 
show little evidence of strikes of these groups or marine mammals from 
the shipping sector and larger vessels (though for many species, 
records do exist, e.g., West et al. 2024, Waerebeek et al., 2007, Van 
Waerebeek et al., 2007), and the majority of the Action Proponents' 
activities involving faster-moving vessels (that could be considered 
more likely to hit a marine mammal) are located in offshore areas where 
smaller delphinid, porpoise, and pinniped densities are lower.
    In order to account for the accidental nature of vessel strike to 
large whales in general, and the potential risk from vessel movement 
within the AFTT Study Area within the 7-year period of this proposed 
authorization, the Action Proponents requested incidental takes based 
on probabilities derived from a Poisson distribution. A Poisson 
distribution is often used to describe random occurrences when the 
probability of an occurrence is small. Count data, such as cetacean 
sighting data, or in this case strike data, are often described as a 
Poisson or over-dispersed Poisson distribution. The Poisson 
distribution was calculated using vessel strike data between 2009-2024 
in the AFTT Study Area, historical at-sea days in the AFTT Study Area 
for the Navy and the Coast Guard (described in detail in section 6 of 
the application), and estimated potential at-sea days for both Action 
Proponents during the 7-year period from 2025-2032 covered by the 
requested regulations. The Navy evaluated data beginning in 2009 as 
that was the start of the Navy's Marine Species Awareness Training and 
adoption of additional mitigation measures to address vessel strike, 
which will remain in place along with additional and modified 
mitigation measures during the 7 years of this rulemaking. Navy vessel 
strike data only accounts for vessels larger than 65 ft (19.8 m) and 
does not include USVs/UUVs as the Navy does not yet have data on their 
use in the AFTT Study Area. The Poisson vessel strike calculations do 
not include any specific number of at-sea days for USVs. Historically, 
the USVs used in the AFTT Study Area were equivalent to small boats. 
While it is anticipated that larger USVs will begin testing in the AFTT 
Study Area during the 7-year period, it was assessed that the addition 
of any at-sea days associated with the limited number of medium or 
large USVs being tested in AFTT would not be large enough to change the 
results of the analysis. In addition, there is no historical strike 
data for USVs. The analysis for the period of 2025 to 2032 is described 
in detail below and in section 6.3.2 (Probability of Vessel Strike of 
Large Whale Species) of the application.
    Between 2009 and early 2024, there were a total of 42,748 Navy at-
sea days and 26,756 Coast Guard at-sea days in the AFTT Study Area. 
During that same time, there were three Navy vessel strikes of large 
whales and three Coast Guard vessel strikes of large whales. From 2025 
through 2032, the Navy anticipates 18,702 at-sea days, and the Coast 
Guard anticipates 11,706 at-sea days.
    To calculate a vessel strike rate for each Action Proponent for the 
period of 2009 through 2024, the Action Proponents used the respective 
number of past vessel strikes of large whales and the respective number 
of at-sea days. Navy at-sea days (for vessels greater than 65 ft (19.8 
m)) from 2009 through 2024 was estimated to be 42,748 days. Dividing 
the three known Navy strikes during that period by the at-sea days 
(i.e., 3 strikes/42,748 at-sea days) results in a strike rate of 
0.000070 strikes per at-sea day. Coast Guard at-sea days (for vessels 
greater than 65 ft (19.8 m)) from 2009 through 2024 was estimated to be 
26,756 days. Dividing the three known Coast Guard strikes during that 
period by the at-sea days (i.e., 3 strikes/26,756 at-sea days) results 
in a strike rate of 0.000112 strikes per day.
    Based on the average annual at-sea days from 2009 to early 2024, 
the Action Proponents estimated that 18,702 Navy and 11,706 Coast Guard 
at-sea days would occur over the 7-year period associated with the 
requested authorization. Given a strike rate of

[[Page 19982]]

0.000070 Navy strikes per at-sea day, and 0.000112 Coast Guard strikes 
per at-sea day, the predicted number of vessel strikes over a 7-year 
period would be 1.31 strikes by the Navy and 1.31 strikes by the Coast 
Guard.
    Using this predicted number of strikes, the Poisson distribution 
predicted the probabilities of a specific number of strikes (n = 0, 1, 
2, etc.) from 2025 through 2032. The probability analysis concluded 
that, for each Action Proponent, there is a 27 percent chance that zero 
whales would be struck by the Action Proponents' vessels over the 7-
year period, and a 35, 23, 10, and 4 percent chance that one, two, 
three, or four whales, respectively, would be struck by each Action 
Proponent over the 7-year period (with a 73 percent chance that at 
least one whale would be struck by each Action Proponent over the 
entire 7-year period). Based on this analysis, the Navy is requesting 
authorization to take three large whales by serious injury or mortality 
by vessel strike incidental to Navy training and testing activities, 
and the Coast Guard is requesting authorization to take three large 
whales by serious injury or mortality by vessel strike incidental to 
Coast Guard training activities. NMFS concurs that take by serious 
injury or mortality by vessel strike of up to three large whales by 
each action proponent (six whales total) could occur over the 7-year 
regulations and, based on the information provided earlier in this 
section, NMFS concurs with the Action Proponents' assessment and 
recognizes the potential for incidental take by vessel strike of large 
whales only (i.e., no dolphins, small whales (not including large whale 
calves), porpoises, or pinnipeds) over the course of the 7-year 
regulations from military readiness activities.
    While the Poisson distribution allows the Action Proponents and 
NMFS to determine the likelihood of vessel strike of all large whales, 
it does not indicate the likelihood of each strike occurring to a 
particular species or stock. As described above, the Action Proponents 
have not always been able to identify the species of large whale struck 
during previous known vessel strikes. Therefore, the Action Proponents 
requested authorization for take by serious injury or mortality by 
vessel strike of any combination of the following stocks in the AFTT 
Study Area, with no more than two takes total from any single stock: 
humpback whale (Gulf of Maine stock), fin whale (Western North Atlantic 
stock), sei whale (Nova Scotia stock), minke whale (Canadian East Coast 
stock), blue whale (Western North Atlantic stock), and sperm whale 
(North Atlantic stock).
    After concurring that take of up to six large whales could occur 
(three takes by each Action Proponent), and in consideration of the 
Navy's request, NMFS considered which species could be among the six 
large whales struck. NMFS conducted an analysis that considered several 
factors: (1) The relative likelihood of striking one stock versus 
another based on available strike data from all vessel types as denoted 
in the SARs, (2) whether each Action Proponent has ever struck an 
individual from a particular species or stock in the AFTT Study Area, 
and if so, how many times, and (3) whether implementation of the 
proposed mitigation measures (i.e., specific measures to reduce the 
potential for vessel strike) would be expected to successfully prevent 
vessel strikes of certain species or stocks (noting that, for all 
stocks, activity-based mitigation would reduce the potential of vessel 
strike).
    To address number (1) above, NMFS compiled information from the 
SARs (Hayes et al., 2024) on detected annual rates of large whale M/SI 
from vessel strike (table 47). The annual rates of large whale serious 
injury or mortality from vessel strike reported in the SARs help inform 
the relative susceptibility of large whale species to vessel strike in 
AFTT Study Area as recorded systematically over the five-year period 
used for the SARs. We summed the annual rates of serious injury or 
mortality from vessel strikes as reported in the SARs and then divided 
each species' annual rate by this sum to get the percentage of total 
annual strikes for each species/stock (table 47).
    To inform the likelihood of a single action proponent striking a 
particular species of large whale, we multiplied the percent of total 
annual strikes for a given species in table 47 by the total percent 
likelihood of a single action proponent striking at least one whale 
(i.e., 73 percent, as described by the probability analysis above). We 
also calculated the percent likelihood of a single action proponent 
striking a particular species of large whale two or three times by 
squaring or cubing, respectively, the value estimated for the 
probability of striking a particular species of whale once (i.e., to 
calculate the probability of an event occurring twice, multiply the 
probability of the first event by the second). The results of these 
calculations are reflected in the last two columns of table 47. We note 
that these probabilities vary from year to year as the average annual 
mortality changes depending on the specific range of time considered; 
however, over the years and through updated data in the SARs, stocks 
tend to consistently maintain a relatively higher or relatively lower 
likelihood of being struck.

  Table 47--Annual Rates of Mortality and Serious Injury From Vessel Collisions and Percent Likelihood of Each Action Proponent Striking a Large Whale
                                                   Species in the AFTT Study Area Over a 7-Year Period
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                  Annual rate of   Percentage      Percent       Percent       Percent
                                                                                     M/SI from      of total     likelihood    likelihood    likelihood
                    Species                                   Stock                vessel strike     annual      of 1 strike  of 2 strikes  of 3 strikes
                                                                                         a           strikes    over 7 years  over 7 years  over 7 years
--------------------------------------------------------------------------------------------------------------------------------------------------------
Blue whale....................................  Western North Atlantic..........               0             0             0             0             0
Fin whale.....................................  Western North Atlantic..........             0.6           8.2             6          0.36          0.02
Humpback whale................................  Gulf of Maine...................             4.4          60.3            44         19.36          8.52
Minke whale...................................  Canadian East Coast.............             0.8            11             8          0.64          0.05
North Atlantic right whale b..................  Western.........................             1.5          20.5            15          2.25          0.34
Rice's whale..................................  Northern Gulf of America........               0             0             0             0             0
Sei whale.....................................  Nova Scotia.....................               0             0             0             0             0
Sperm whale...................................  North Atlantic..................               0             0             0             0             0
Sperm whale...................................  Northern Gulf of America........               0             0             0             0             0
--------------------------------------------------------------------------------------------------------------------------------------------------------
a Values are from the most recent stock assessment report (Hayes et al., 2024).
b While these percentages suggest that NARW has a quantitatively higher likelihood of vessel strike in comparison with other stocks, this proposed
  rulemaking includes extensive mitigation measures for NARW that would minimize the risk of vessel strike such that vessel strike of this stock is not
  anticipated to occur. Please see the discussion in this section and the Proposed Mitigation Measures section for additional detail.


[[Page 19983]]

    The percent likelihood calculated (as described above) are then 
considered in combination with the information indicating the known 
species that the Navy or Coast Guard has struck in the AFTT Study Area 
since 2000 (table 48). We note that for the lethal take of species 
specifically denoted in table 48 below, most of those struck by the 
Navy or Coast Guard remained unidentified. However, given the 
information on known stocks struck, the analysis below remains 
appropriate.

Table 48--Number of Known Vessel Strikes by Each Action Proponent in the
                         AFTT Study Area by Year
------------------------------------------------------------------------
                                                          Coast Guard
            Year                U.S. Navy strikes      strikes (species/
                                 (species/stock)            stock)
------------------------------------------------------------------------
2000.......................  1 (unknown)............  0.
2001.......................  4 (3 unknown, one
                              probable Puerto Rico/
                              U.S. Virgin Islands
                              stock sperm whale).
2004.......................  3 (unknown)............
2005.......................  2 (1 unknown, 1
                              probable sperm whale).
2009.......................  .......................  2 (NARW).
2011.......................  1 (unknown, probable
                              humpback whale).
2012.......................  2 (1 unknown, 1
                              probable humpback).
2021.......................  1 (dolphin)............
2024.......................  .......................  1 (unknown,
                                                       probable humpback
                                                       whale).
------------------------------------------------------------------------

    Accordingly, stocks that have no record of ever having been struck 
by any vessel are considered to have a zero percent likelihood of being 
struck by the Navy in the 7-year period of the rule. While the Western 
North Atlantic stock of blue whales, Northern Gulf of America stock of 
Rice's whale, Nova Scotia stock of sei whales, and North Atlantic stock 
of sperm whales have a reported annual rate of M/SI from vessel strike 
of 0, each of these stocks have records of strikes prior to the period 
reported in the SAR (Hayes et al. 2024). There is record of a vessel 
strike in 1996 of a Western North Atlantic blue whale (Hayes et al. 
2024), two records of vessel strike of Rice's whale (one in 2009 and 
one in 2019), several records of vessel strikes in the 1990s and early 
2000s of North Atlantic sperm whales, and a record of a probable sperm 
whale (Northern Gulf of America stock) strike in 1990. For the Nova 
Scotia stock of sei whale, several sei whale strandings during the time 
period analyzed for the SAR (i.e., 2017-2021) had an undetermined cause 
of death (Garron, 2022), and M/SI by vessel strike for sei whales along 
the U.S. East Coast were a more common occurrence in previous SAR 5-
year periods (i.e., four from 2012-2016, three from 2007-2011, and two 
from 2002-2006). Therefore, NMFS included each of these stocks for 
further analysis, and considered the historical strikes, but lack of 
recent strikes to inform the relative likelihood that the Navy or Coast 
Guard would strike these stocks.
    While Bryde's whales in the Atlantic are not a NMFS-managed stock, 
the low number of estimated takes by harassment (11 takes by Level B 
harassment) indicate very low overlap of this stock with the Action 
Proponents' activities. As such, and given that there are no records of 
either action proponent having struck Bryde's whale in the Atlantic in 
the past, NMFS neither anticipates, nor proposes to authorize, serious 
injury or mortality by vessel strike of Bryde's whale.
    To address number (2) above, the percent likelihoods of a certain 
number of strikes of each stock are then considered in combination with 
the information indicating the species that the Action Proponents have 
definitively struck in the AFTT Study Area since 2009. As noted above, 
since 2009, the U.S. Navy and Coast Guard have each struck three whales 
in the AFTT Study Area. The Navy struck one unidentified species in 
June 2011, one unidentified species (thought to likely be a humpback) 
in February 2012, and one unidentified species in October 2012. The 
Coast Guard struck two whales (reported as NARW) in December 2009, and 
one unidentified large whale (thought to likely be a humpback) in 2024.
    Stocks that have never been struck by the Navy, have rarely been 
struck by other vessels, and have a low percent likelihood based on the 
historical vessel strike calculation are also considered to have a zero 
percent likelihood to be struck by the Navy during the 7-year rule. As 
noted in table 48, in 2001, the Navy struck an unidentified whale in 
the Gulf of America, and given the stocks that occur there, that this 
strike was of either a sperm whale or Rice's whale. Given the relative 
abundance of these two stocks, NMFS expects that this strike was likely 
of a sperm whale (Northern Gulf of America stock). Therefore, this step 
in the analysis rules out take by vessel strike of blue whale and 
Rice's whale. Even if the 2001 strike had been of a Rice's whale, 
consideration of the proposed geographic mitigation for Rice's whale 
(see Proposed Mitigation Measures section below) and the low stock 
abundance further supports the conclusion that vessel strike of Rice's 
whale is unlikely. This leaves the following stocks for further 
analysis: fin whale (Western North Atlantic stock), humpback whale 
(Gulf of Maine stock), minke whale (Canadian Eastern Coastal stock), 
NARW (Western stock), sei whale (Nova Scotia stock), and sperm whale 
(North Atlantic and Northern Gulf of America stocks).
    Based on the information summarized in table 47, and the fact that 
there is potential for up to six large whales to be struck over the 7-
year duration of this rulemaking, NMFS anticipates that each action 
proponent could strike one of each of the following stocks (two total 
per stock across both action proponents): fin whales (Western North 
Atlantic stock), minke whales (Canadian Eastern Coastal stock), sei 
whales (Nova Scotia stock), and sperm whales (North Atlantic stock). 
NMFS also anticipates that the Navy may strike up to one sperm whale 
(Northern Gulf of America stock) given the 2001 likely sperm whale 
strike. Given the already lower likelihood of striking this stock given 
the relatively lower vessel activity in the Gulf of America portion of 
the AFTT Study Area, and the relatively lower Coast Guard vessel 
traffic compared to Navy vessel traffic, NMFS neither anticipates, nor 
proposes to authorize, a Coast Guard strike of this stock. NMFS 
anticipates that each Action Proponent could strike up to two humpback 
whales (Gulf of Maine stock) given the higher relative strike 
likelihood indicated in table 47, and the Action

[[Page 19984]]

Proponents' conclusion that several previous Navy and Coast Guard 
strikes of unidentified species were likely humpback whales.
    Following the conclusion for the stocks above, NARW is the only 
remaining stock. NARW are known to be particularly susceptible to 
vessel strike, and vessel strike is one of the greatest threats to this 
stock. NMFS' quantitative analysis (table 47) indicates a 15 percent 
likelihood of one strike of NARW over the 7-year duration of this 
proposed rulemaking. However, for the reasons described below, NMFS 
does not anticipate vessel strike of NARW by either action proponent. 
As stated previously, in 2009, the Coast Guard struck two whales 
(reported as NARW). Since 2009, the Navy has had no known strikes of 
NARW, and it has been implementing extensive mitigation measures to 
avoid vessel strike of NARW. The lack of known strikes of NARWs 
indicates that the mitigation used by the Navy since 2009 and included 
here for the Action Proponents has likely been successful. Given that 
the Navy will continue to implement this mitigation for NARW, and the 
Coast Guard will begin implementing it also, (e.g., funding of and 
communication with sightings systems, awareness of slow zones and 
dynamic management areas for NARW) we neither anticipate nor propose to 
authorize take by serious injury or mortality by vessel strike of NARW. 
Please see the Proposed Mitigation Measures section of this proposed 
rulemaking and section 11 of the application for additional detail.
    In conclusion, although it is generally unlikely that any whales 
will be struck in a year, based on the information and analysis above, 
NMFS anticipates that no more than six takes of large whales by serious 
injury or mortality could occur over the 7-year period of the rule, 
with no more than three by each Action Proponent. Of those six whales 
over the 7 years, no more than four may come from the Gulf of Maine 
stock of humpback whale; no more than two may come from the Western 
North Atlantic stock of fin whale, the Canadian East Coast stock of 
minke whale, the Nova Scotia stock of sei whale, and the North Atlantic 
stock of sperm whale; no more than one strike by the Navy may come from 
the Northern Gulf of America stock of sperm whale. Accordingly, NMFS 
has evaluated under the negligible impact standard the M/SI of 0.14, 
0.29 or 0.57 whales annually from each of these species or stocks 
(i.e., 1, 2 or 4 takes, respectively, divided by 7 years to get the 
annual value), along with the expected incidental takes by harassment.

Summary of Requested Take From Military Readiness Activities

    Table 49 and table 50 summarize the Action Proponents' take 
proposed by harassment type and effect type, respectively.

                      Table 49--Total Annual and 7-Year Incidental Take Proposed by Stock During All Activities by Harassment Type
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                            Maximum      Maximum
                                                                             annual       annual      Maximum   7-Year total  7-Year total  7-Year total
                  Species                               Stock               Level B      Level A      annual       Level B       Level A      mortality
                                                                           harassment   harassment   mortality   harassment    harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale................  Western.....................          414            2           0         2,682             8             0
Blue whale................................  Western North Atlantic......           71            1           0           464             2             0
Bryde's whale.............................  Primary.....................           11            0           0            70             0             0
Fin whale.................................  Western North Atlantic......        2,616           21        0.29        17,298           131             2
Humpback whale............................  Gulf of Maine...............          844           12        0.57         5,544            74             4
Minke whale...............................  Canadian East Coast.........        4,643           56        0.29        31,006           377             2
Rice's whale..............................  Northern Gulf of America....          303            3           0         2,047             6             0
Sei whale.................................  Nova Scotia.................          747            7        0.29         4,981            44             2
Sperm whale...............................  North Atlantic..............       12,590            7        0.29        84,675            21             2
Sperm whale...............................  Northern Gulf of America....          275            0        0.29         1,653             0             1
Dwarf sperm whale.........................  Northern Gulf of America....          189           22           0         1,112            73             0
Pygmy sperm whale.........................  Northern Gulf of America....          175           22           0         1,017            65             0
Dwarf sperm whale.........................  Western North Atlantic......        6,326          180           0        42,547         1,184             0
Pygmy sperm whale.........................  Western North Atlantic......        6,294          176           0        42,302         1,157             0
Blainville's beaked whale.................  Northern Gulf of America....          126            0           0           812             0             0
Goose-beaked whale........................  Northern Gulf of America....          460            0           0         2,962             0             0
Gervais' beaked whale.....................  Northern Gulf of America....          125            0           0           800             0             0
Blainville's beaked whale.................  Western North Atlantic......       25,705            1           0       172,587             1             0
Goose-beaked whale........................  Western North Atlantic......      112,070            2           0       752,587             5             0
Gervais' beaked whale.....................  Western North Atlantic......       25,446            1           0       172,339             1             0
Northern bottlenose whale.................  Western North Atlantic......         1651            1           0        10,879             1             0
Sowerby's beaked whale....................  Western North Atlantic......       25,622            1           0       173,546             1             0
True's beaked whale.......................  Western North Atlantic......       25,582            0           0       173,301             0             0
Atlantic spotted dolphin..................  Northern Gulf of America....       12,804           20           0        83,827           123             0
Bottlenose dolphin........................  Gulf of America Eastern                80            0           0           455             0             0
                                             Coastal.
Bottlenose dolphin........................  Gulf of America Northern            7,146           17           0        49,950           114             0
                                             Coastal.
Bottlenose dolphin........................  Gulf of America, Oceanic....        6,274            4           0        40,584            11             0
Bottlenose dolphin........................  Gulf of America Western             3,331            1           0        18,123             1             0
                                             Coastal.
Bottlenose dolphin........................  Mississippi Sound, Lake             1,758            1           0        12,014             1             0
                                             Borgne, and Bay Boudreau.
Bottlenose dolphin........................  Northern Gulf of America           71,331           29           0       481,391           165             0
                                             Continental Shelf.
Bottlenose dolphin........................  Nueces and Corpus Christi               4            0           0            11             0             0
                                             Bays.
Bottlenose dolphin........................  Sabine Lake.................            1            0           0             2             0             0
Bottlenose dolphin........................  St. Andrew Bay..............           46            0           0           303             0             0
Bottlenose dolphin........................  St. Joseph Bay..............           42            0           0           287             0             0
Bottlenose dolphin........................  Tampa Bay...................          350            0           0         1,050             0             0
Clymene dolphin...........................  Northern Gulf of America....          599            3           0         3,577             4             0
False killer whale........................  Northern Gulf of America....          230            0           0         1,423             0             0
Fraser's dolphin..........................  Northern Gulf of America....          241            0           0         1,487             0             0
Killer whale..............................  Northern Gulf of America....          110            0           0           680             0             0
Melon-headed whale........................  Northern Gulf of America....          771            1           0         4,806             1             0
Pygmy killer whale........................  Northern Gulf of America....          285            0           0         1,773             0             0
Risso's dolphin...........................  Northern Gulf of America....          203            0           0         1,252             0             0

[[Page 19985]]

 
Rough-toothed dolphin.....................  Northern Gulf of America....        1,642            3           0        10,808             5             0
Short-finned pilot whale..................  Northern Gulf of America....        1,021            3           0         6,183            13             0
Striped dolphin...........................  Northern Gulf of America....        2,376            7        0.29        15,414            15             2
Pantropical spotted dolphin...............  Northern Gulf of America....        6,316            9        0.71        39,959            28             5
Spinner dolphin...........................  Northern Gulf of America....          656            0           0         4,459             0             0
Atlantic white-sided dolphin..............  Western North Atlantic......       10,901            9           0        71,669            43             0
Common dolphin............................  Western North Atlantic......      269,405          161           0     1,820,556         1,015             0
Atlantic spotted dolphin..................  Western North Atlantic......      120,798           87           0       796,804           577             0
Bottlenose dolphin........................  Indian River Lagoon                 1,576            0           0        10,675             0             0
                                             Estuarine System.
Bottlenose dolphin........................  Jacksonville Estuarine                360            0           0         2,477             0             0
                                             System.
Bottlenose dolphin........................  Northern Georgia/Southern               2            0           0             6             0             0
                                             South Carolina Estuarine
                                             System.
Bottlenose dolphin........................  Northern North Carolina            10,532            6           0        72,036            37             0
                                             Estuarine System.
Bottlenose dolphin........................  Southern Georgia Estuarine            123            1           0           711             1             0
                                             System.
Bottlenose dolphin........................  Southern North Carolina               162            0           0           535             0             0
                                             Estuarine System.
Tamanend's bottlenose dolphin.............  Western North Atlantic             10,494            3           0        66,392            10             0
                                             Central Florida Coastal.
Tamanend's bottlenose dolphin.............  Western North Atlantic             21,385            5           0       142,945            13             0
                                             Northern Florida Coastal.
Bottlenose dolphin........................  Western North Atlantic             73,720           60           0       507,610           375             0
                                             Northern Migratory Coastal.
Bottlenose dolphin........................  Western North Atlantic            187,046          103        0.29     1,246,451           677             2
                                             Offshore.
Tamanend's Bottlenose dolphin.............  Western North Atlantic South        4,960            6        0.14        30,781            22             1
                                             Carolina/Georgia Coastal.
Bottlenose dolphin........................  Western North Atlantic             10,180            9           0        64,883            52             0
                                             Southern Migratory Coastal.
Clymene dolphin...........................  Western North Atlantic......      132,723          104        0.43       902,324           698             3
False killer whale........................  Western North Atlantic......          572            1           0         3,872             1             0
Fraser's dolphin..........................  Western North Atlantic......        2,905            3           0        19,435            14             0
Killer whale..............................  Western North Atlantic......          180            1           0         1,195             1             0
Long-finned pilot whale...................  Western North Atlantic......       21,680           12           0       146,009            63             0
Melon-headed whale........................  Western North Atlantic......        4,598            3           0        31,086            12             0
Pantropical spotted dolphin...............  Western North Atlantic......       13,068            5           0        89,174            25             0
Pygmy killer whale........................  Western North Atlantic......          477            1           0         3,226             1             0
Risso's dolphin...........................  Western North Atlantic......       37,239           25           0       245,877           143             0
Rough-toothed dolphin.....................  Western North Atlantic......        4,753            6           0        31,562            25             0
Short-finned pilot whale..................  Western North Atlantic......       33,035           15           0       222,007            91             0
Spinner dolphin...........................  Western North Atlantic......        5,356            2           0        36,513            10             0
Striped dolphin...........................  Western North Atlantic......      208,802          163           0     1,397,838         1,109             0
White-beaked dolphin......................  Western North Atlantic......           16            0           0           103             0             0
Harbor porpoise...........................  Gulf of Maine/Bay of Fundy..       87,119          147           0       586,732           954             0
Gray seal.................................  Western North Atlantic......       15,724           24           0       105,585           151             0
Harbor seal...............................  Western North Atlantic......       22,094           32           0       148,486           204             0
Harp seal.................................  Western North Atlantic......       25,792            6           0       174,649            28             0
Hooded seal...............................  Western North Atlantic......        1,726            2           0        10,985             5             0
--------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 19986]]


                                            Table 50--Total Annual and 7-Year Incidental Take Proposed by Stock During All Activities by Effect Type
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                     Maximum
                                                                                    Maximum    Maximum    Maximum     annual    Maximum   Maximum 7-             Maximum 7- Maximum 7- Maximum 7-
                 Species                                   Stock                    annual      annual     annual      non-      annual      year     Maximum 7-  year AUD  year non-     year
                                                                                  behavioral     TTS      AUD INJ    auditory  mortality  behavioral   year TTS     INJ      auditory  mortality
                                                                                                                      injury                                                  injury
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale...............  Western..............................         109        305          2          0          0         715      1,967          8          0          0
Blue whale...............................  Western North Atlantic...............          12         59          1          0          0          73        391          2          0          0
Bryde's whale............................  Primary..............................           2          9          0          0          0           7         63          0          0          0
Fin whale................................  Western North Atlantic...............         689      1,927         21          0       0.29       4,526     12,772        131          0          2
Humpback whale...........................  Gulf of Maine........................         212        632         12          0       0.57       1,404      4,140         74          0          4
Minke whale..............................  Canadian East Coast..................         693      3,950         56          0       0.29       4,637     26,369        377          0          2
Rice's whale.............................  Northern Gulf of America.............          88        215          3          0          0         593      1,454          6          0          0
Sei whale................................  Nova Scotia..........................         125        622          7          0       0.29         822      4,159         44          0          2
Sperm whale..............................  North Atlantic.......................       8,878      3,712          6          1       0.29      59,196     25,479         20          1          2
Sperm whale..............................  Northern Gulf of America.............         248         27          0          0       0.29       1,507        146          0          0          1
Dwarf sperm whale........................  Northern Gulf of America.............          27        162         22          0          0         148        964         73          0          0
Pygmy sperm whale........................  Northern Gulf of America.............          28        147         22          0          0         163        854         65          0          0
Dwarf sperm whale........................  Western North Atlantic...............       1,308      5,018        180          0          0       8,686     33,861      1,184          0          0
Pygmy sperm whale........................  Western North Atlantic...............       1,341      4,953        176          0          0       8,907     33,395      1,157          0          0
Blainville's beaked whale................  Northern Gulf of America.............         126          0          0          0          0         812          0          0          0          0
Blainville's beaked whale................  Western North Atlantic...............      25,551        154          1          0          0     171,535      1,052          1          0          0
Goose-beaked whale.......................  Northern Gulf of America.............         457          3          0          0          0       2,959          3          0          0          0
Goose-beaked whale.......................  Western North Atlantic...............     111,457        613          2          0          0     748,360      4,227          5          0          0
Gervais' beaked whale....................  Northern Gulf of America.............         123          2          0          0          0         798          2          0          0          0
Gervais' beaked whale....................  Western North Atlantic...............      25,110        336          1          0          0     170,030      2,309          1          0          0
Northern bottlenose whale................  Western North Atlantic...............       1,642          9          1          0          0      10,822         57          1          0          0
Sowerby's beaked whale...................  Western North Atlantic...............      25,257        365          1          0          0     171,033      2,513          1          0          0
True's beaked whale......................  Western North Atlantic...............      25,217        365          0          0          0     170,797      2,504          0          0          0
Atlantic spotted dolphin.................  Northern Gulf of America.............       7,085      5,719         20          0          0      46,690     37,137        123          0          0
Bottlenose dolphin.......................  Gulf of America Eastern Coastal......          75          5          0          0          0         433         22          0          0          0
Bottlenose dolphin.......................  Gulf of America Northern Coastal.....       6,524        622         17          0          0      45,608      4,342        114          0          0
Bottlenose dolphin.......................  Gulf of America Oceanic..............       4,764      1,510          4          0          0      30,923      9,661         11          0          0
Bottlenose dolphin.......................  Gulf of America Western Coastal......       1,773      1,558          1          0          0       9,846      8,277          1          0          0
Bottlenose dolphin.......................  Mississippi Sound, Lake Borgne, and         1,715         43          1          0          0      11,776        238          1          0          0
                                            Bay Boudreau.
Bottlenose dolphin.......................  Northern Gulf of America Continental       46,801     24,530         27          2          0     321,346    160,045        163          2          0
                                            Shelf.
Bottlenose dolphin.......................  Nueces and Corpus Christi Bays.......           4          0          0          0          0          11          0          0          0          0
Bottlenose dolphin.......................  Sabine Lake..........................           1          0          0          0          0           2          0          0          0          0
Bottlenose dolphin.......................  St. Andrew Bay.......................          45          1          0          0          0         302          1          0          0          0
Bottlenose dolphin.......................  St. Joseph Bay.......................          42          0          0          0          0         287          0          0          0          0
Bottlenose dolphin.......................  Tampa Bay............................         163        187          0          0          0         490        560          0          0          0
Clymene dolphin..........................  Northern Gulf of America.............         390        209          2          1          0       2,308      1,269          3          1          0
False killer whale.......................  Northern Gulf of America.............         168         62          0          0          0       1,036        387          0          0          0
Fraser's dolphin.........................  Northern Gulf of America.............         168         73          0          0          0       1,031        456          0          0          0
Killer whale.............................  Northern Gulf of America.............          84         26          0          0          0         521        159          0          0          0
Melon-headed whale.......................  Northern Gulf of America.............         579        192          1          0          0       3,600      1,206          1          0          0
Pygmy killer whale.......................  Northern Gulf of America.............         204         81          0          0          0       1,263        510          0          0          0
Risso's dolphin..........................  Northern Gulf of America.............         155         48          0          0          0         967        285          0          0          0
Rough-toothed dolphin....................  Northern Gulf of America.............         988        654          2          1          0       6,531      4,277          4          1          0
Short-finned pilot whale.................  Northern Gulf of America.............         629        392          3          0          0       3,771      2,412         13          0          0
Striped dolphin..........................  Northern Gulf of America.............       1,728        648          5          2       0.29      11,266      4,148         10          5          2
Pantropical spotted dolphin..............  Northern Gulf of America.............       4,589      1,727          6          3       0.71      29,025     10,934         20          8          5
Spinner dolphin..........................  Northern Gulf of America.............         478        178          0          0          0       3,241      1,218          0          0          0
Atlantic white-sided dolphin.............  Western North Atlantic...............       7,172      3,729          8          1          0      46,544     25,125         40          3          0
Common dolphin...........................  Western North Atlantic...............     136,920    132,485        159          2          0     924,362    896,194      1,010          5          0
Atlantic spotted dolphin.................  Western North Atlantic...............      51,840     68,958         85          2          0     343,981    452,823        571          6          0
Bottlenose dolphin.......................  Indian River Lagoon Estuarine System.       1,438        138          0          0          0       9,717        958          0          0          0
Bottlenose dolphin.......................  Jacksonville Estuarine System........         269         91          0          0          0       1,855        622          0          0          0
Bottlenose dolphin.......................  Northern Georgia/Southern South                 2          0          0          0          0           6          0          0          0          0
                                            Carolina Estuarine System.
Bottlenose dolphin.......................  Northern North Carolina Estuarine           8,579      1,953          6          0          0      59,058     12,978         37          0          0
                                            System.
Bottlenose dolphin.......................  Southern Georgia Estuarine System....          85         38          1          0          0         499        212          1          0          0
Bottlenose dolphin.......................  Southern North Carolina Estuarine              82         80          0          0          0         256        279          0          0          0
                                            System.

[[Page 19987]]

 
Tamanend's bottlenose dolphin............  Western North Atlantic Central              7,921      2,573          2          1          0      52,787     13,605          8          2          0
                                            Florida Coastal.
Tamanend's bottlenose dolphin............  Western North Atlantic Northern            17,054      4,331          5          0          0     116,843     26,102         13          0          0
                                            Florida Coastal.
Bottlenose dolphin.......................  Western North Atlantic Northern            57,217     16,503         59          1          0     397,269    110,341        374          1          0
                                            Migratory Coastal.
Bottlenose dolphin.......................  Western North Atlantic Offshore......      91,255     95,791        101          2       0.29     609,321    637,130        671          6          2
Tamanend's bottlenose dolphin............  Western North Atlantic South Carolina/      1,426      3,534          6          0       0.14       8,970     21,811         22          0          1
                                            Georgia Coastal.
Bottlenose dolphin.......................  Western North Atlantic Southern             2,936      7,244          8          1          0      18,993     45,890         48          4          0
                                            Migratory Coastal.
Clymene dolphin..........................  Western North Atlantic...............      60,223     72,500        102          2       0.43     403,316    499,008        694          4          3
False killer whale.......................  Western North Atlantic...............         317        255          1          0          0       2,143      1,729          1          0          0
Fraser's dolphin.........................  Western North Atlantic...............       1,362      1,543          3          0          0       9,135     10,300         14          0          0
Killer whale.............................  Western North Atlantic...............         100         80          1          0          0         659        536          1          0          0
Long-finned pilot whale..................  Western North Atlantic...............      12,783      8,897         11          1          0      85,545     60,464         62          1          0
Melon-headed whale.......................  Western North Atlantic...............       1,993      2,605          3          0          0      13,543     17,543         12          0          0
Pantropical spotted dolphin..............  Western North Atlantic...............       6,436      6,632          5          0          0      44,269     44,905         25          0          0
Pygmy killer whale.......................  Western North Atlantic...............         216        261          1          0          0       1,471      1,755          1          0          0
Risso's dolphin..........................  Western North Atlantic...............      20,226     17,013         23          2          0     133,055    112,822        141          2          0
Rough-toothed dolphin....................  Western North Atlantic...............       1,874      2,879          6          0          0      12,519     19,043         25          0          0
Short-finned pilot whale.................  Western North Atlantic...............      16,978     16,057         15          0          0     113,894    108,113         91          0          0
Spinner dolphin..........................  Western North Atlantic...............       2,607      2,749          2          0          0      17,788     18,725         10          0          0
Striped dolphin..........................  Western North Atlantic...............     107,596    101,206        161          2          0     708,184    689,654      1,103          6          0
White-beaked dolphin.....................  Western North Atlantic...............          10          6          0          0          0          64         39          0          0          0
Harbor porpoise..........................  Gulf of Maine/Bay of Fundy...........      81,105      6,014        147          0          0     547,161     39,571        954          0          0
Gray seal................................  Western North Atlantic...............       9,811      5,913         24          0          0      66,633     38,952        151          0          0
Harbor seal..............................  Western North Atlantic...............      13,406      8,688         32          0          0      91,406     57,080        204          0          0
Harp seal................................  Western North Atlantic...............      16,636      9,156          6          0          0     111,591     63,058         28          0          0
Hooded seal..............................  Western North Atlantic...............       1,080        646          2          0          0       6,740      4,245          5          0          0
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: This includes effects from sonar and other transducers, air guns, pile driving, explosives (including small ship shock trials), and vessel strike.


[[Page 19988]]

Proposed Mitigation Measures

    Under section 101(a)(5)(A) of the MMPA, NMFS must set forth the 
permissible methods of taking pursuant to the activity, and other means 
of effecting the least practicable adverse impact on the species or 
stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance, and on the 
availability of the species or stocks for subsistence uses (``least 
practicable adverse impact''). NMFS does not have a regulatory 
definition for least practicable adverse impact. The 2004 NDAA amended 
the MMPA as it relates to military readiness activities and the 
incidental take authorization process such that a determination of 
``least practicable adverse impact'' shall include consideration of 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity. For additional 
discussion of NMFS' interpretation of the least practicable adverse 
impact standard, see the Mitigation Measures section of the Gulf of 
Alaska Study Area final rule (88 FR 604, January 4, 2023).

Implementation of Least Practicable Adverse Impact Standard

    Here, we discuss how we determine whether a measure or set of 
measures meets the ``least practicable adverse impact'' standard. Our 
separate analysis of whether the take anticipated to result from the 
Action Proponents' activities meets the ``negligible impact'' standard 
appears in the Preliminary Analysis and Negligible Impact Determination 
section below.
    Our evaluation of potential mitigation measures includes 
consideration of two primary factors: (1) The manner in which, and the 
degree to which, implementation of the potential measure(s) is expected 
to reduce adverse impacts to marine mammal species or stocks, their 
habitat, or their availability for subsistence uses (where relevant). 
This analysis considers such things as the nature of the potential 
adverse impact (such as likelihood, scope, and range), the likelihood 
that the measure will be effective if implemented, and the likelihood 
of successful implementation; and (2) The practicability of the 
measure(s) for applicant implementation. Practicability of 
implementation may consider such things as cost, impact on activities, 
and, in the case of a military readiness activity, specifically 
considers personnel safety, practicality of implementation, and impact 
on the effectiveness of the military readiness activity.
    While the language of the least practicable adverse impact standard 
calls for minimizing impacts to affected species or stocks, we 
recognize that the reduction of impacts to those species or stocks 
accrues through the application of mitigation measures that limit 
impacts to individual animals. Accordingly, NMFS' analysis focuses on 
measures that are designed to avoid or minimize impacts on individual 
marine mammals that are more likely to increase the probability or 
severity of population-level effects.
    While direct evidence of impacts to species or stocks from a 
specified activity is rarely available, and additional study is still 
needed to understand how specific disturbance events affect the fitness 
of individuals of certain species, there have been improvements in 
understanding the process by which disturbance effects are translated 
to the population. With recent scientific advancements (both marine 
mammal energetic research and the development of energetic frameworks), 
the relative likelihood or degree of impacts on species or stocks may 
often be inferred given a detailed understanding of the activity, the 
environment, and the affected species or stocks--and the best available 
science has been used here. This same information is used in the 
development of mitigation measures and helps us understand how 
mitigation measures contribute to lessening effects (or the risk 
thereof) to species or stocks. We also acknowledge that there is always 
the potential that new information, or a new recommendation, could 
become available in the future and necessitate reevaluation of 
mitigation measures (which may be addressed through adaptive 
management) to see if further reductions of population impacts are 
possible and practicable.
    In the evaluation of specific measures, the details of the 
specified activity will necessarily inform each of the two primary 
factors discussed above (expected reduction of impacts and 
practicability), and are carefully considered to determine the types of 
mitigation that are appropriate under the least practicable adverse 
impact standard. Analysis of how a potential mitigation measure may 
reduce adverse impacts on a marine mammal stock or species, 
consideration of personnel safety, practicality of implementation, and 
consideration of the impact on effectiveness of military readiness 
activities are not issues that can be meaningfully evaluated through a 
yes/no lens. The manner in which, and the degree to which, 
implementation of a measure is expected to reduce impacts, as well as 
its practicability in terms of these considerations, can vary widely. 
For example, a time/area restriction could be of very high value for 
decreasing population-level impacts (e.g., avoiding disturbance of 
feeding females in an area of established biological importance) or it 
could be of lower value (e.g., decreased disturbance in an area of high 
productivity but of less biological importance). Regarding 
practicability, a measure might involve restrictions in an area or time 
that impede the Navy's ability to certify a strike group (higher impact 
on mission effectiveness), or it could mean delaying a small in-port 
training event by 30 minutes to avoid exposure of a marine mammal to 
injurious levels of sound (lower impact). A responsible evaluation of 
``least practicable adverse impact'' will consider the factors along 
these realistic scales. Accordingly, the greater the likelihood that a 
measure will contribute to reducing the probability or severity of 
adverse impacts to the species or stock or its habitat, the greater the 
weight that measure is given when considered in combination with 
practicability to determine the appropriateness of the mitigation 
measure, and vice versa. We discuss consideration of these factors in 
greater detail below.
    1. Reduction of adverse impacts to marine mammal species or stocks 
and their habitat. The emphasis given to a measure's ability to reduce 
the impacts on a species or stock considers the degree, likelihood, and 
context of the anticipated reduction of impacts to individuals (and how 
many individuals) as well as the status of the species or stock.
    The ultimate impact on any individual from a disturbance event 
(which informs the likelihood of adverse species- or stock-level 
effects) is dependent on the circumstances and associated contextual 
factors, such as duration of exposure to stressors. Though any proposed 
mitigation needs to be evaluated in the context of the specific 
activity and the species or stocks affected, measures with the 
following types of effects have greater value in reducing the 
likelihood or severity of adverse species- or stock-level impacts: 
avoiding or minimizing injury or mortality; limiting interruption of 
known feeding, breeding, mother/young, or resting behaviors; minimizing 
the abandonment of important habitat (temporally and spatially); 
minimizing the number of individuals subjected to these types of 
disruptions; and limiting degradation of habitat. Mitigating these

[[Page 19989]]

types of effects is intended to reduce the likelihood that the activity 
will result in energetic or other types of impacts that are more likely 
to result in reduced reproductive success or survivorship. It is also 
important to consider the degree of impacts that are expected in the 
absence of mitigation in order to assess the added value of any 
potential measures. Finally, because the least practicable adverse 
impact standard gives NMFS discretion to weigh a variety of factors 
when determining appropriate mitigation measures and because the focus 
of the standard is on reducing impacts at the species or stock level, 
the least practicable adverse impact standard does not compel 
mitigation for every kind of take, or every individual taken, if that 
mitigation is unlikely to meaningfully contribute to the reduction of 
adverse impacts on the species or stock and its habitat, even when 
practicable for implementation by the applicant.
    The status of the species or stock is also relevant in evaluating 
the appropriateness of potential mitigation measures in the context of 
least practicable adverse impact. The following are examples of factors 
that may (either alone, or in combination) result in greater emphasis 
on the importance of a mitigation measure in reducing impacts on a 
species or stock: the stock is known to be decreasing or status is 
unknown, but believed to be declining; the known annual mortality (from 
any source) is approaching or exceeding the potential biological 
removal (PBR) level (as defined in MMPA section 3(20)); the affected 
species or stock is a small, resident population; or the stock is 
involved in a UME or has other known vulnerabilities, such as 
recovering from an oil spill.
    Habitat mitigation, particularly as it relates to rookeries, mating 
grounds, and areas of similar significance, is also relevant to 
achieving the standard and can include measures such as reducing 
impacts of the activity on known prey utilized in the activity area or 
reducing impacts on physical habitat. As with species- or stock-related 
mitigation, the emphasis given to a measure's ability to reduce impacts 
on a species or stock's habitat considers the degree, likelihood, and 
context of the anticipated reduction of impacts to habitat. Because 
habitat value is informed by marine mammal presence and use, in some 
cases there may be overlap in measures for the species or stock and for 
use of habitat. We consider available information indicating the 
likelihood of any measure to accomplish its objective. If evidence 
shows that a measure has not typically been effective nor successful, 
then either that measure should be modified or the potential value of 
the measure to reduce effects should be lowered.
    2. Practicability. Factors considered may include cost, impact on 
activities, and, in the case of a military readiness activity, will 
include personnel safety, practicality of implementation, and impact on 
the effectiveness of the military readiness activity (see MMPA section 
101(a)(5)(A)(ii)).

Assessment of Mitigation Measures for the AFTT Study Area

    NMFS has fully reviewed the specified activities and the mitigation 
measures included in the application and the 2024 AFTT Draft 
Supplemental EIS/OEIS to determine if the mitigation measures would 
result in the least practicable adverse impact on marine mammals and 
their habitat. NMFS worked with the Action Proponents in the 
development of their initially proposed measures, which are informed by 
years of implementation and monitoring. A complete discussion of the 
Action Proponents' evaluation process used to develop, assess, and 
select mitigation measures, which was informed by input from NMFS, can 
be found in chapter 5 (Mitigation) of the 2024 AFTT Draft Supplemental 
EIS/OEIS. The process described in chapter 5 (Mitigation) and appendix 
A (Activity Descriptions) of the 2024 AFTT Draft Supplemental EIS/OEIS 
robustly supported NMFS' independent evaluation of whether the 
mitigation measures would meet the least practicable adverse impact 
standard. The Action Proponents would be required to implement the 
mitigation measures identified in this rule for the full 7 years to 
avoid or reduce potential impacts from acoustic, explosive, and 
physical disturbance and strike stressors.
    As a general matter, where an applicant proposes measures that are 
likely to reduce impacts to marine mammals, the fact that they are 
included in the application indicates that the measures are 
practicable, and it is not necessary for NMFS to conduct a detailed 
analysis of the measures the applicant proposed (rather, they are 
simply included). However, it is still necessary for NMFS to consider 
whether there are additional practicable measures that would 
meaningfully reduce the probability or severity of impacts that could 
affect reproductive success or survivorship.
    Overall the Action Proponents have agreed to mitigation measures 
that would reduce the probability and/or severity of impacts expected 
to result from acute exposure to acoustic sources or explosives, vessel 
strike, and impacts to marine mammal habitat. Specifically, the Action 
Proponents would use a combination of delayed starts, powerdowns, and 
shutdowns to avoid mortality or serious injury, minimize the likelihood 
or severity of AUD INJ or non-auditory injury, and reduce instances of 
TTS or more severe behavioral disturbance caused by acoustic sources or 
explosives. The Action Proponents would also implement multiple time/
area restrictions that would reduce take of marine mammals in areas or 
at times where they are known to engage in important behaviors, such as 
calving, where the disruption of those behaviors would have a higher 
probability of resulting in impacts on reproduction or survival of 
individuals that could lead to population-level impacts.
    The Action Proponents assessed the practicability of the proposed 
measures in the context of personnel safety, practicality of 
implementation, and their impacts on the Action Proponents' ability to 
meet their Congressionally mandated requirements and found that the 
measures are supportable. As described in more detail below, NMFS has 
independently evaluated the measures the Action Proponents proposed in 
the manner described earlier in this section (i.e., in consideration of 
their ability to reduce adverse impacts on marine mammal species and 
their habitat and their practicability for implementation). We have 
determined that the measures would significantly reduce impacts on the 
affected marine mammal species and stocks and their habitat and, 
further, be practicable for implementation by the Action Proponents. We 
have preliminarily determined that the mitigation measures assure that 
the Action Proponents' activities would have the least practicable 
adverse impact on the species or stocks and their habitat.
    The Action Proponents also evaluated numerous measures in the 2024 
AFTT Draft Supplemental EIS/OEIS that were not included in the 
application, and NMFS independently reviewed and preliminarily concurs 
with the Action Proponents' analysis that their inclusion was not 
appropriate under the least practicable adverse impact standard based 
on our assessment. The Action Proponents considered these additional 
potential mitigation measures in the context of the potential benefits 
to marine mammals and whether they are practical or impractical.
    Section 5.9 (Measures Considered but Eliminated) of chapter 5 
(Mitigation) of

[[Page 19990]]

the 2024 AFTT Draft Supplemental EIS/OEIS, includes an analysis of an 
array of different types of mitigation that have been recommended over 
the years by non-governmental organizations or the public, through 
scoping or public comment on environmental compliance documents. These 
recommendations generally fall into three categories, discussed below: 
reduction of activity, activity-based operational measures, and time/
area limitations.
    As described in section 5.9 (Measures Considered but Eliminated) of 
the 2024 AFTT Draft Supplemental EIS/OEIS, the Action Proponents 
considered reducing the overall amount of training, reducing explosive 
use, modifying sound sources, completely replacing live training with 
computer simulation, and including time of day restrictions. Many of 
these mitigation measures could potentially reduce the number of marine 
mammals taken via direct reduction of the activities or amount of sound 
energy put in the water. However, as described in chapter 5 
(Mitigation) of the 2024 AFTT Draft Supplemental EIS/OEIS, the Action 
Proponents need to train in the conditions in which they fight--and 
these types of modifications fundamentally change the activity in a 
manner that would not support the purpose and need for the training 
(i.e., are entirely impracticable) and therefore are not considered 
further. NMFS finds the Action Proponents' explanation of why adoption 
of these recommendations would unacceptably undermine the purpose of 
the training persuasive. After independent review, NMFS finds the 
Action Proponents' judgment on the impacts of these potential 
mitigation measures to personnel safety, practicality of 
implementation, and the effectiveness of training persuasive, and for 
these reasons, NMFS finds that these measures do not meet the least 
practicable adverse impact standard because they are not practicable.
    Also in chapter 5 (Mitigation) of the 2024 AFTT Draft Supplemental 
EIS/OEIS, the Action Proponents evaluated additional potential 
activity-based mitigation measures, including increased mitigation 
zones, ramp-up measures, additional passive acoustic and visual 
monitoring, and decreased vessel speeds. Some of these measures have 
the potential to incrementally reduce take to some degree in certain 
circumstances, though the degree to which this would occur is typically 
low or uncertain. However, as described in the Action Proponents' 
analysis, the measures would have significant direct negative effects 
on mission effectiveness and are considered impracticable (see chapter 
5 of the 2024 AFTT Draft Supplemental EIS/OEIS). NMFS independently 
reviewed the Action Proponents' evaluation and concurs with this 
assessment, which supports NMFS' preliminary findings that the 
impracticability of this additional mitigation would greatly outweigh 
any potential minor reduction in marine mammal impacts that might 
result; therefore, these additional mitigation measures are not 
warranted.
    Last, chapter 5 (Mitigation) of the 2024 AFTT Draft Supplemental 
EIS/OEIS also describes a comprehensive analysis of potential 
geographic mitigation that includes consideration of both a biological 
assessment of how the potential time/area limitation would benefit the 
species and its habitat (e.g., is a key area of biological importance 
or would result in avoidance or reduction of impacts) in the context of 
the stressors of concern in the specific area and an operational 
assessment of the practicability of implementation (e.g., including an 
assessment of the specific importance of an area for training, 
considering proximity to training ranges and emergency landing fields 
and other issues). In some cases potential benefits to marine mammals 
were non-existent, while in others the consequences on mission 
effectiveness were too great.
    NMFS has reviewed the Action Proponents' analysis in chapter 5 
(Mitigation) and appendix A (Activity Descriptions) of the 2024 AFTT 
Draft Supplemental EIS/OEIS, which consider the same factors that NMFS 
considers to satisfy the least practicable adverse impact standard, and 
concurs with the analysis and conclusions. Therefore, NMFS is not 
proposing to include any of the measures that the Action Proponents 
ruled out in the 2024 AFTT Draft Supplemental EIS/OEIS. Below are the 
mitigation measures that NMFS has preliminarily determined would ensure 
the least practicable adverse impact on all affected species and their 
habitat, including the specific considerations for military readiness 
activities. Table 51 describes the information designed to aid Lookouts 
and other applicable personnel with their observation, environmental 
compliance, and reporting responsibilities. The following sections 
describe the mitigation measures that would be implemented in 
association with the activities analyzed in this document. The 
mitigation measures are organized into two categories: activity-based 
mitigation and geographic mitigation areas.
    Of note, according to the U.S. Navy, consistent with customary 
international law, when a foreign military vessel participates in a 
U.S. Navy exercise within the U.S. territorial sea (i.e., 0 to 12 nmi 
(0 to 22.2 km) from shore), the U.S. Navy will request that the foreign 
vessel follow the U.S. Navy's mitigation measures for that particular 
event. When a foreign military vessel participates in a U.S. Navy 
exercise beyond the U.S. territorial sea but within the U.S. Exclusive 
Economic Zone, the U.S. Navy will encourage the foreign vessel to 
follow the U.S. Navy's mitigation measures for that particular event 
(Navy 2022a; Navy 2022b). In either scenario (i.e., both within and 
beyond the territorial sea), U.S. Navy personnel will provide the 
foreign vessels participating with a description of the mitigation 
measures to follow.

             Table 51--Environmental Awareness and Education
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: All training and testing activities, as
 applicable.
------------------------------------------------------------------------
Requirements: Navy personnel (including civilian personnel) involved in
 mitigation and training or testing activity reporting under the
 specified activities must complete one or more modules of the U.S. Navy
 Afloat Environmental Compliance Training Series, as identified in their
 career path training plan. Modules include:
     Introduction to Afloat Environmental Compliance Training
     Series. The introductory module provides information on
     environmental laws (e.g., ESA, MMPA) and the corresponding
     responsibilities that are relevant to military readiness
     activities. The material explains why environmental compliance is
     important in supporting the Action Proponents' commitment to
     environmental stewardship.
     Marine Species Awareness Training. All bridge watch
     personnel, Commanding Officers, Executive Officers, maritime patrol
     aircraft aircrews, anti-submarine warfare and mine warfare rotary-
     wing aircrews, Lookouts, and equivalent civilian personnel must
     successfully complete the Marine Species Awareness Training prior
     to standing watch or serving as a Lookout. The Marine Species
     Awareness Training provides information on sighting cues, visual
     observation tools and techniques, and sighting notification
     procedures. Navy biologists developed Marine Species Awareness
     Training to improve the effectiveness of visual observations for
     biological resources, focusing on marine mammals and sea turtles,
     and including floating vegetation, jellyfish aggregations, and
     flocks of seabirds.

[[Page 19991]]

 
     Protective Measures Assessment Protocol. This module
     provides the necessary instruction for accessing mitigation
     requirements during the event planning phase using the Protective
     Measures Assessment Protocol (PMAP) software tool.
     Sonar Positional Reporting System and Marine Mammal
     Incident Reporting. This module provides instruction on the
     procedures and activity reporting requirements for the Sonar
     Positional Reporting System and marine mammal incident reporting.
------------------------------------------------------------------------

Activity-Based Mitigation

    Activity-based mitigation is mitigation that the Action Proponents 
would implement whenever and wherever an applicable military readiness 
activity takes place within the AFTT Study Area. Previously referred to 
as ``Procedural Mitigation,'' the primary objective of activity-based 
mitigation is to reduce overlap of marine mammals with stressors that 
have the potential to cause injury or mortality in real time. Activity-
based mitigations are fundamentally consistent across stressor 
activity, although specific variations account for differences in 
platform configuration, event characteristics, and stressor types. The 
Action Proponents customize mitigation for each applicable activity 
category or stressor. Activity-based mitigation generally involves: (1) 
The use of one or more trained Lookouts to diligently observe for 
marine mammals and other specific biological resources (e.g., indicator 
species like floating vegetation, jelly aggregations, large schools of 
fish, and flocks of seabirds) within a mitigation zone, (2) 
requirements for Lookouts to immediately communicate sightings of 
marine mammals and other specific biological resources to the 
appropriate watch station for information dissemination, and (3) 
requirements for the watch station to implement mitigation (e.g., halt 
an activity) until certain recommencement conditions have been met. The 
remainder of the mitigation measures are activity-based mitigation 
measures (table 52 through table 70) organized by stressor type and 
activity category and include acoustic stressors (i.e., active sonar, 
air guns, pile driving, weapons firing noise), explosive stressors 
(i.e., sonobuoys, torpedoes, medium-caliber and large-caliber 
projectiles, missiles and rockets, bombs, SINKEX, mine counter-measure 
and neutralization activities, mine neutralization involving Navy 
divers, line charge testing, ship shock trials), and physical 
disturbance and strike stressors (i.e., vessel movement, towed in-water 
devices, small-, medium-, and large-caliber non-explosive practice 
munitions, non-explosive missiles and rockets, non-explosive bombs, 
mine shapes).
    The Action Proponents must implement the proposed mitigation 
measures described in table 52 through table 70, as appropriate, in 
response to an applicable sighting within, or entering into, the 
relevant mitigation zone for acoustic stressors, explosives, and non-
explosive munitions. Each table describes the activities that the 
requirements apply to, the required mitigation zones in which the 
action proponents must take a mitigation action, the required number of 
Lookouts and observation platform, the required mitigation actions that 
the action proponents must take before, during, and/or after an 
activity, and a required wait period prior to commencing or 
recommencing an activity after a delay, power down, or shutdown of an 
activity.
    The Action Proponents proposed wait periods because events cannot 
be delayed or ceased indefinitely for the purpose of mitigation due to 
impacts on safety, sustainability, and the ability to meet mission 
requirements. Wait periods are designed to allow animals the maximum 
amount of time practical to resurface (i.e., become available to be 
observed) before activities resume. The action proponents factored in 
an assumption that mitigation may need to be implemented more than once 
when developing wait period durations. Wait periods are 10 minutes, 15 
minutes, or 30 minutes depending on the fuel constraints of the 
platform and feasibility of implementation. NMFS concurs with these 
proposed wait periods.
    If an applicable species (identified in relevant mitigation table) 
is observed within a required mitigation zone prior to the initial 
start of the activity, the Action Proponents must: (1) relocate the 
event to a location where applicable species are not observed, or (2) 
delay the initial start of the event (or stressor use) until one of the 
``Mitigation Zone All-Clear Conditions'' (defined below) has been met. 
If an applicable stressor is observed within a required mitigation zone 
during the event (i.e., during use of the indicated source) the Action 
Proponents must take the action described in the ``Mitigation Zones'' 
section of the table until one of the Mitigation Zone All-Clear 
Conditions has been met.
    For all activities, an activity may not commence or recommence 
until one of the following ``Mitigation Zone All-Clear Conditions'' 
have been met: (1) a Lookout observes the applicable species exiting 
the mitigation zone, (2) a Lookout determines the applicable species 
has exited the mitigation zone based on its observed course and speed 
relative to the mitigation zone, (3) a Lookout affirms the mitigation 
zone has been clear from additional sightings for a designated ``wait 
period,'' or (4) for mobile events, the stressor has transited a 
distance equal to double the mitigation zone size beyond the location 
of the last sighting.
Activity-Based Mitigation for Active Acoustic Stressors
    Mitigation measures for acoustic stressors are provided below and 
include active acoustic sources (table 52), pile driving and extraction 
(table 53), and weapons firing noise (table 54). Activity-based 
mitigation for acoustic stressors does not apply to:
    (i) sources not operated under positive control (i.e., sources not 
actively controlled by a crewmember, e.g., unmanned platforms 
performing predetermined operations);
    (ii) sources used for safety of navigation;
    (iii) sources used or deployed by aircraft operating at high 
altitudes;
    (iv) sources used, deployed, or towed by unmanned platforms except 
when escort vessels are already participating in the event and have 
positive control over the source;
    (v) sources used by submerged submarines;
    (vi) de minimis sources;
    (vii) long-duration sources, including those used for acoustic and 
oceanographic research; and
    (viii) vessel-based, unmanned vehicle-based, or towed in-water 
sources when marine mammals (e.g., dolphins) are determined to be 
intentionally swimming at the bow or alongside or directly behind the 
vessel, vehicle, or device (e.g., to bow-ride or wake-ride).

[[Page 19992]]



            Table 52--Mitigation for Active Acoustic Sources
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Active acoustic sources with power down and shut
 down capabilities:
     Low-frequency active sonar >=200 dB.
     Mid-frequency active sonar sources that are hull mounted on
     a surface ship (including surfaced submarines).
     Broadband and other active acoustic sources >200 dB.
------------------------------------------------------------------------
     Mitigation Zones:
        [cir] 1,000 yd (914.4 m) from active acoustic sources (power
         down of 6 dB total).
        [cir] 500 yd (457.2 m) from active acoustic sources (power down
         of 10 dB total).
        [cir] 200 yd (182.9 m) from active acoustic sources (shut down).
     Mitigation Requirements:
        [cir] One Lookout in/on one of the following:
            [ssquf] Aircraft.
            [ssquf] Pierside, moored, or anchored vessel.
            [ssquf] Underway vessel with space/crew restrictions
             (including small boats).
            [ssquf] Underway vessel already participating in the event
             that is escorting (and has positive control over sources
             used, deployed, or towed by) an unmanned platform.
        [cir] Two Lookouts on an underway vessel without space/crew
         restrictions.
        [cir] Lookouts would use information from passive acoustic
         detections to inform visual observations when passive acoustic
         devices are already being used in the event.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals and floating vegetation
         immediately prior to the initial start of using active acoustic
         sources (e.g., while maneuvering on station).
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals during use of active
         acoustic sources.
     Wait Period:
        [cir] 10 or 30 minutes (depending on fuel constraints of the
         platform).
------------------------------------------------------------------------
Stressor or Activity: Active acoustic sources with shut down (but not
 power down) capabilities:
     Low-frequency active sonar <200 dB.
     Mid-frequency active sonar sources that are not hull
     mounted on a surface ship (e.g., dipping sonar, towed arrays).
     High-frequency active sonar.
     Air guns.
     Broadband and other active acoustic sources <200 dB.
------------------------------------------------------------------------
     Mitigation Zone:
         200 yd (182.9 m) from active acoustic sources (shut
         down).
     Mitigation Requirements:
         One Lookout in/on one of the following:
             Aircraft.
             Pierside, moored, or anchored vessel.
             Underway vessel with space/crew restrictions
             (including small boats).
             Underway vessel already participating in the event
             that is escorting (and has positive control over sources
             used, deployed, or towed by) an unmanned platform.
         Two Lookouts on an underway vessel without space/crew
         restrictions.
         Lookouts would use information from passive acoustic
         detections to inform visual observations when passive acoustic
         devices are already being used in the event.
     Mitigation Requirement Timing:
         Action Proponent personnel must observe the mitigation
         zone for marine mammals and floating vegetation immediately
         prior to the initial start of using active acoustic sources
         (e.g., while maneuvering on station).
         Action Proponent personnel must observe the mitigation
         zone for marine mammals during use of active acoustic sources.
     Wait Period:
         10 or 30 minutes (depending on fuel constraints of the
         platform).
------------------------------------------------------------------------


          Table 53--Mitigation for Pile Driving and Extraction
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Vibratory and impact pile driving and extraction.
------------------------------------------------------------------------
     Mitigation Zone:
         100 yd (91.4 m) from piles being driven or extracted
         (cease pile driving or extraction).
     Mitigation Requirements
         One Lookout on one of the following:
             Shore.
             Pier.
             Small boat.
     Mitigation Requirement Timing:
         Action Proponent personnel must observe the mitigation
         zone for marine mammals and floating vegetation for 15 minutes
         prior to the initial start of pile driving or pile extraction.
         Action Proponent personnel must observe the mitigation
         zone for marine mammals during pile driving or extraction.
     Wait Period:
         15 minutes.
------------------------------------------------------------------------


[[Page 19993]]


              Table 54--Mitigation for Weapons Firing Noise
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Explosive and non-explosive large-caliber gunnery
 firing noise (surface-to-surface and surface-to-air).
------------------------------------------------------------------------
     Mitigation Zone:
         30 degrees on either side of the firing line out to 70
         yd (64 m) from the gun muzzle (cease fire).
     Mitigation Requirements:
         One Lookout on a vessel.
     Mitigation Requirement Timing:
         Action Proponent personnel must observe the mitigation
         zone for marine mammals and floating vegetation immediately
         prior to the initial start of large-caliber gun firing (e.g.,
         during target deployment).
         Action Proponent personnel must observe the mitigation
         zone for marine mammals during large-caliber gun firing.
     Wait Period:
         30 minutes.
------------------------------------------------------------------------

Activity-Based Mitigation for Explosive Stressors
    Mitigation measures for explosive stressors are provided below and 
include explosive bombs (table 55), explosive gunnery (table 56), 
explosive line charges (table 57), explosive mine countermeasure and 
neutralization without divers (table 58), explosive mine neutralization 
with divers (table 59), explosive missiles and rockets (table 60), 
explosive sonobuoys and research-based sub-surface explosives (table 
61), explosive torpedoes (table 62), ship shock trials (table 63), and 
SINKEX (table 64). After the event, the Action Proponents must observe 
the area for marine mammals. Post-event observations are intended to 
aid incident reporting requirements for marine mammals. Practicality 
and the duration of post-event observations will be determined on site 
by fuel restrictions and mission-essential follow-on commitments. For 
example, it is more challenging to remain on-site for extended periods 
of time for some activities due to factors such as range from the 
target or altitude of an aircraft. Activity-based mitigation for 
explosive stressors does not apply to explosives:
    (i) deployed by aircraft operating at high altitudes;
    (ii) deployed by submerged submarines, except for explosive 
torpedoes;
    (iii) deployed against aerial targets;
    (iv) during vessel-launched missile or rocket events;
    (v) used at or below the de minimis threshold; and
    (vi) deployed by unmanned platforms except when escort vessels are 
already participating in the event and have positive control over the 
explosive.

                Table 55--Mitigation for Explosive Bombs
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Any NEW.
------------------------------------------------------------------------
     Mitigation Zone:
        [cir] 2,500 yd (2,286 m) from the intended target (cease fire).
     Mitigation Requirements:
        [cir] One Lookout in an aircraft.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals and floating vegetation
         immediately prior to the initial start of bomb delivery (e.g.,
         when arriving on station).
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals during bomb delivery.
        [cir] After the event, when practical, Action Proponent
         personnel must observe the detonation vicinity for injured or
         dead marine mammals. If any injured or dead marine mammals are
         observed, Action Proponent personnel must follow established
         incident reporting procedures.
     Wait Period:
        [cir] 10 minutes.
------------------------------------------------------------------------


               Table 56--Mitigation for Explosive Gunnery
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Air-to-surface medium-caliber, surface-to-surface
 medium-caliber, surface-to-surface large-caliber.
------------------------------------------------------------------------
     Mitigation Zones:
        [cir] Air-to-surface medium-caliber:
            [ssquf] 200 yd (182.9 m) from the intended impact location
             (cease fire).
        [cir] Surface-to-surface medium-caliber:
            [ssquf] 600 yd (548.6 m) from the intended impact location
             (cease fire).
        [cir] Surface-to-surface large-caliber:
            [ssquf] 1,000 yd (914.4 m) from the intended impact location
             (cease fire).
     Mitigation Requirements:
        [cir] One Lookout on a vessel or in an aircraft.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals and floating vegetation
         immediately prior to the initial start of gun firing (e.g.,
         while maneuvering on station).
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals during gunnery fire.
        [cir] After the event, when practical, Action Proponent
         personnel must observe the detonation vicinity for injured or
         dead marine mammals. If any injured or dead marine mammals are
         observed, Action Proponent personnel must follow established
         incident reporting procedures.
     Wait Period:

[[Page 19994]]

 
        [cir] 10 or 30 minutes (depending on fuel constraints of the
         platform).
------------------------------------------------------------------------


             Table 57--Mitigation for Explosive Line Charges
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Any NEW.
------------------------------------------------------------------------
     Mitigation Zone:
        [cir] 900 yd (823 m) from the detonation site (cease fire).
     Mitigation Requirements:
        [cir] One Lookout on a vessel.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals and floating vegetation immediately
         prior to the initial start of detonations (e.g., while
         maneuvering on station).
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals during detonations.
        [cir] After the event, when practical, Action Proponent
         personnel must observe the detonation vicinity for injured or
         dead marine mammals. If any injured or dead marine mammals are
         observed, Action Proponent personnel must follow established
         incident reporting procedures.
     Wait Period:
        [cir] 30 minutes.
------------------------------------------------------------------------


       Table 58--Mitigation for Explosive Mine Countermeasure and
                       Neutralization (No Divers)
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: 0.1-5 lb (0.05-2.3 kg) NEW, >5 lb (2.3 kg) NEW.
------------------------------------------------------------------------
     Mitigation Zones:
        [cir] 0.1-5 lb (0.05-2.3 kg) NEW:
            [ssquf] 600 yd (548.6 m) from the detonation site (cease
             fire).
        [cir] >5 lb (2.3 kg) NEW:
            [ssquf] 2,100 yd (1,920.2 m) from the detonation site (cease
             fire).
     Mitigation Requirements:
        [cir] 0.1-5 lb (0.05-2.3 kg) NEW:
            [ssquf] One Lookout on a vessel or in an aircraft.
        [cir] >5 lb (2.3 kg) NEW:
            [ssquf] Two Lookouts: one on a small boat and one in an
             aircraft.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals and floating vegetation
         immediately prior to the initial start of detonations (e.g.,
         while maneuvering on station; typically, 10 or 30 minutes
         depending on fuel constraints).
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals during detonations or fuse
         initiation.
        [cir] After the event, when practical, Action Proponent
         personnel must observe the detonation vicinity for 10 or 30
         minutes (depending on fuel constraints) for injured or dead
         marine mammals. If any injured or dead marine mammals are
         observed, Action Proponent personnel must follow established
         incident reporting procedures.
     Wait Period:
        [cir] 10 or 30 minutes (depending on fuel constraints of the
         platform).
------------------------------------------------------------------------


  Table 59--Mitigation for Explosive Mine Neutralization (With Divers)
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: 0.1-20 lb (0.05-9.1 kg) NEW (positive control),
 0.1-20 lb (0.05-9.1 kg) NEW (time-delay), >20-60 lb (9.1-27.2 kg) NEW
 (positive control).
------------------------------------------------------------------------
     Mitigation Zones:
        [cir] 0.1-20 lb (0.05-9.1 kg) NEW (positive control):
            [ssquf] 500 yd (457.2 m) from the detonation site (cease
             fire).
        [cir] 0.1-20 lb (0.05-9.1 kg) NEW (time-delay), >20-60 lb (9.1-
         27.2 kg) NEW (positive control):
            [ssquf] 1,000 yd (914.4 m) from the detonation site (cease
             fire).
     Mitigation Requirements:
        [cir] 0.1-20 lb (0.05-9.1 kg) NEW (positive control):
            [ssquf] Two Lookouts in two small boats (one Lookout per
             boat) or one small boat and one rotary-wing aircraft (with
             one Lookout each).
        [cir] 0.1-20 lb (0.05-9.1 kg) NEW (time-delay), >20-60 lb (9.1-
         27.2 kg) NEW (positive control):
            [ssquf] Four Lookouts in two small boats (two Lookouts per
             boat), and one additional Lookout in an aircraft if used in
             the event.
     Mitigation Requirement Timing:
        [cir] Time-delay devices must be set not to exceed 10 minutes.
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals and floating vegetation
         immediately prior to the initial start of detonations or fuse
         initiation for positive control events (e.g., while maneuvering
         on station) or for 30 minutes prior for time-delay events.
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals during detonations or fuse
         initiation.
        [cir] When practical based on mission, safety, and environmental
         conditions:
            [ssquf] Boats must observe from the mitigation zone radius
             mid-point.
            [ssquf] When two boats are used, boats must observe from
             opposite sides of the mine location.
            [ssquf] Platforms must travel a circular pattern around the
             mine location.
            [ssquf] Boats must have one Lookout observe inward toward
             the mine location and one Lookout observe outward toward
             the mitigation zone perimeter.

[[Page 19995]]

 
            [ssquf] Divers must be part of the Lookout Team.
        [cir] After the event, when practical, Action Proponent
         personnel must observe the detonation vicinity for 30 minutes
         for injured or dead marine mammals. If any injured or dead
         marine mammals are observed, Action Proponent personnel must
         follow established incident reporting procedures.
     Wait Period:
        [cir] 10 or 30 minutes (depending on fuel constraints of the
         platform).
------------------------------------------------------------------------


         Table 60--Mitigation for Explosive Missiles and Rockets
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: 0.6-20 lb (0.3-9.1 kg) NEW (air-to-surface), >20-
 500 lb (9.1-226.8 kg) NEW (air-to-surface).
------------------------------------------------------------------------
     Mitigation Zones:
        [cir] 0.6-20 lb (0.3-9.1 kg) NEW (air-to-surface):
            [ssquf] 900 yd (823 m) from the intended impact location
             (cease fire).
        [cir] >20-500 lb (9.1-226.8 kg) NEW (air-to-surface):
            [ssquf] 2,000 yd (1,828.8 m) from the intended impact
             location (cease fire).
     Mitigation Requirements:
        [cir] One Lookout in an aircraft.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals and floating vegetation
         immediately prior to the initial start of missile or rocket
         delivery (e.g., during a fly-over of the mitigation zone).
        [cir] Action Proponent personnel must observe the applicable
         mitigation zone for marine mammals during missile or rocket
         delivery.
        [cir] After the event, when practical, Action Proponent
         personnel must observe the detonation vicinity for injured or
         dead marine mammals. If any injured or dead marine mammals are
         observed, Action Proponent personnel must follow established
         incident reporting procedures.
     Wait Period:
        [cir] 10 or 30 minutes (depending on fuel constraints of the
         platform).
------------------------------------------------------------------------


  Table 61--Mitigation for Explosive Sonobuoys and Research-Based Sub-
                           Surface Explosives
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Any NEW of sonobuoys, 0.1-5 lb (0.05-2.3 kg) NEW
 for other types of sub-surface explosives used in research
 applications.
------------------------------------------------------------------------
     Mitigation Zones:
        [cir] 600 yd (548.6 m) from the device or detonation sites
         (cease fire).
     Mitigation Requirements:
        [cir] One Lookout on a small boat or in an aircraft.
        [cir] Conduct passive acoustic monitoring for marine mammals;
         use information from detections to assist visual observations.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals and floating vegetation immediately
         prior to the initial start of detonations (e.g., during
         sonobuoy deployment, which typically lasts 20-30 minutes).
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals during detonations.
        [cir] After the event, when practical, Action Proponent
         personnel must observe the detonation vicinity for injured or
         dead marine mammals. If any injured or dead marine mammals are
         observed, Action Proponent personnel must follow established
         incident reporting procedures.
     Wait Period:
        [cir] 10 or 30 minutes (depending on fuel constraints of the
         platform).
------------------------------------------------------------------------


              Table 62--Mitigation for Explosive Torpedoes
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Any NEW.
------------------------------------------------------------------------
     Mitigation Zone:
        [cir] 2,100 yd (1,920.2 m) from the intended impact location
         (cease fire).
     Mitigation Requirements:
        [cir] One Lookout in an aircraft.
        [cir] Conduct passive acoustic monitoring for marine mammals;
         use information from detections to assist visual observations.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals, floating vegetation, and jellyfish
         aggregations immediately prior to the initial start of
         detonations (e.g., during target deployment).
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals and jellyfish aggregations during
         torpedo launches.
        [cir] After the event, when practical, Action Proponent
         personnel must observe the detonation vicinity for injured or
         dead marine mammals. If any injured or dead marine mammals are
         observed, Action Proponent personnel must follow established
         incident reporting procedures.
     Wait Period:
        [cir] 10 or 30 minutes (depending on fuel constraints of the
         platform).
------------------------------------------------------------------------


[[Page 19996]]


               Table 63--Mitigation for Ship Shock Trials
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Any NEW.
------------------------------------------------------------------------
     Mitigation Zone:
        [cir] 3.5 nmi (6.5 km) from the target ship hull (cease fire).
     Mitigation Requirements:
        [cir] On the day of the event, 10 observers (Lookouts and third-
         party observers combined), spread between aircraft or multiple
         vessels as specified in the event-specific mitigation plan.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must develop a detailed, event-
         specific monitoring and mitigation plan in the year prior to
         the event and provide it to NMFS for review.
        [cir] Beginning at first light on days of detonation, until the
         moment of detonation (as allowed by safety measures) Action
         Proponent personnel must observe the mitigation zone for marine
         mammals, floating vegetation, jellyfish aggregations, large
         schools of fish, and flocks of seabirds.
        [cir] If any dead or injured marine mammals are observed after
         an individual detonation, Action Proponent personnel must
         follow established incident reporting procedures and halt any
         remaining detonations until Action Proponent personnel or third-
         party observers can consult with NMFS and review or adapt the
         event-specific mitigation plan, if necessary.
        [cir] During the 2 days following the event (minimum) and up to
         7 days following the event (maximum), and as specified in the
         event-specific mitigation plan, Action Proponent personnel must
         observe the detonation vicinity for injured or dead marine
         mammals.
     Wait Period:
        [cir] 30 minutes.
------------------------------------------------------------------------


           Table 64--Mitigation for Sinking Exercises (SINKEX)
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Any NEW.
------------------------------------------------------------------------
     Mitigation Zone:
        [cir] 2.5 nmi (4.6 km) from the target ship hull (cease fire).
     Mitigation Requirements:
        [cir] Two Lookouts: one on a vessel and one in an aircraft.
        [cir] Conduct passive acoustic monitoring for marine mammals;
         use information from detections to assist visual observations.
     Mitigation Requirement Timing:
        [cir] During aerial observations for 90 minutes prior to the
         initial start of weapon firing, Action Proponent personnel must
         observe the mitigation zone for marine mammals, floating
         vegetation, and jellyfish aggregations.
        [cir] From the vessel during weapon firing, and from the
         aircraft and vessel immediately after planned or unplanned
         breaks in weapon firing of more than 2 hours, Action Proponent
         personnel must observe the mitigation zone for marine mammals.
        [cir] Action Proponent personnel must observe the detonation
         vicinity for injured or dead marine mammals for 2 hours after
         sinking the vessel or until sunset, whichever comes first. If
         any injured or dead marine mammals are observed, Action
         Proponent personnel must follow established incident reporting
         procedures.
     Wait Period:
        [cir] 30 minutes.
------------------------------------------------------------------------

Activity-Based Mitigation for Non-Explosive Ordnance
    Mitigation measures for non-explosive ordnance are provided below 
and include non-explosive aerial-deployed mines and bombs (table 65), 
non-explosive gunnery (table 66), and non-explosive missiles and 
rockets (table 67). Explosive aerial-deployed mines do not detonate 
upon contact with the water surface and are therefore considered non-
explosive when mitigating the potential for a mine shape to strike a 
marine mammal at the water surface. Activity-based mitigation for non-
explosive ordnance does not apply to non-explosive ordnance deployed:
    (i) by aircraft operating at high altitudes;
    (ii) against aerial targets;
    (iii) during vessel-launched missile or rocket events; and
    (iv) by unmanned platforms except when escort vessels are already 
participating in the event and have positive control over ordnance 
deployment.

 Table 65--Mitigation for Non-Explosive Aerial-Deployed Mines and Bombs
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Non-explosive aerial-deployed mines and non-
 explosive bombs.
------------------------------------------------------------------------
     Mitigation Zone:
        [cir] 1,000 yd (914.4 m) from the intended target (cease fire).
     Mitigation Requirements:
        [cir] One Lookout in an aircraft.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals and floating vegetation immediately
         prior to the initial start of mine or bomb delivery (e.g., when
         arriving on station).
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals during mine or bomb delivery.
     Wait Period:
        [cir] 10 minutes.
------------------------------------------------------------------------


[[Page 19997]]


             Table 66--Mitigation for Non-Explosive Gunnery
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Non-explosive surface-to-surface large-caliber
 ordnance, non-explosive surface-to-surface and air-to-surface medium-
 caliber ordnance, non-explosive surface-to-surface and air-to-surface
 small-caliber ordnance.
------------------------------------------------------------------------
     Mitigation Zone:
        [cir] 200 yd (182.9 m) from the intended impact location (cease
         fire).
     Mitigation Requirements:
        [cir] One Lookout on a vessel or in an aircraft.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals and floating vegetation immediately
         prior to the start of gun firing (e.g., while maneuvering on
         station).
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals during gunnery firing.
     Wait Period:
        [cir] 10 or 30 minutes (depending on fuel constraints of the
         platform).
------------------------------------------------------------------------


       Table 67--Mitigation for Non-Explosive Missiles and Rockets
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Non-explosives (air-to-surface).
------------------------------------------------------------------------
     Mitigation Zone:
        [cir] 900 yd (823 m) from the intended impact location (cease
         fire).
     Mitigation Requirements:
        [cir] One Lookout in an aircraft.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals and floating vegetation immediately
         prior to the start of missile or rocket delivery (e.g., during
         a fly-over of the mitigation zone).
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals during missile or rocket delivery.
     Wait Period:
        [cir] 10 or 30 minutes (depending on fuel constraints of the
         platform).
------------------------------------------------------------------------

Activity-Based Mitigation for Physical Disturbance and Strike Stressors
    Mitigation measures for physical disturbance and strike stressors 
are provided below and include manned surface vessels (table 68), 
unmanned vehicles (table 69), and towed in-water devices (table 70).

             Table 68--Mitigation for Manned Surface Vessels
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Manned surface vessels, including surfaced
 submarines.
------------------------------------------------------------------------
     Mitigation Zones:
        [cir] Underway manned surface vessels must maneuver themselves
         (which may include reducing speed) to maintain the following
         distances as mission and circumstances allow:
            [ssquf] 500 yd (457.2 m) from whales.
            [ssquf] 200 yd (182.9 m) from other marine mammals.
     Mitigation Requirements:
        [cir] One or more Lookouts on manned underway surface vessels in
         accordance with the most recent navigation safety instruction.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals immediately prior to manned surface
         vessels getting underway and while underway.
------------------------------------------------------------------------


               Table 69--Mitigation for Unmanned Vehicles
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: Unmanned Surface Vehicles and Unmanned Underwater
 Vehicles already being escorted (and operated under positive control)
 by a manned surface support vessel.
------------------------------------------------------------------------
     Mitigation Zones:
        [cir] A surface support vessel that is already participating in
         the event, and has positive control over the unmanned vehicle,
         must maneuver the unmanned vehicle (which may include reducing
         its speed) to ensure it maintains the following distances as
         mission and circumstances allow:
            [ssquf] 500 yd (457.2 m) from whales.
            [ssquf] 200 yd (182.9 m) from other marine mammals.
     Mitigation Requirements:
        [cir] One Lookout on a surface support vessel that is already
         participating in the event, and has positive control over the
         unmanned vehicle.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals immediately prior to unmanned vehicles
         getting underway and while underway, the Lookout must observe.
------------------------------------------------------------------------


[[Page 19998]]


             Table 70--Mitigation for Towed In-Water Devices
------------------------------------------------------------------------
 
-------------------------------------------------------------------------
Stressor or Activity: In-water devices towed by an aircraft, a manned
 surface vessel, or an Unmanned Surface Vehicle or Unmanned Underwater
 Vehicle already being escorted (and operated under positive control) by
 a manned surface vessel.
------------------------------------------------------------------------
     Mitigation Zone:
        [cir] Manned towing platforms, or surface support vessels
         already participating in the event that have positive control
         over an unmanned vehicle that is towing an in-water device,
         must maneuver itself or the unmanned vehicle (which may include
         reducing speed) to ensure towed in-water devices maintain the
         following distances as mission and circumstances allow:
            [ssquf] 250 yd (228.6 m) from marine mammals.
     Mitigation Requirements:
        [cir] One Lookout on the manned towing vessel, or on a surface
         support vessel that is already participating in the event and
         has positive control over an unmanned vehicle that is towing an
         in-water device.
     Mitigation Requirement Timing:
        [cir] Action Proponent personnel must observe the mitigation
         zone for marine mammals immediately prior to and while in-water
         devices are being towed.
------------------------------------------------------------------------

Geographic Mitigation Areas

    In addition to activity-based mitigation, the Action Proponents 
would implement mitigation measures within mitigation areas to avoid or 
minimize potential impacts on marine mammals (see figure 11.6-1 of the 
application). A full technical analysis of the mitigation areas that 
the Action Proponents considered for marine mammals is provided in 
section 5.7 (Geographic Mitigation) of the 2024 AFTT Draft Supplemental 
EIS/OEIS. The Action Proponents took into account public comments 
received on the 2018 AFTT Draft EIS/OEIS, the best available science, 
and the practicability of implementing additional mitigation measures 
and has enhanced its mitigation areas and mitigation measures beyond 
those that were included in the 2018-2025 regulations to further reduce 
impacts to marine mammals.
    Information on the mitigation measures that the Action Proponents 
propose to implement within mitigation areas are provided in table 71 
through table 78. The mitigation applies year-round unless specified 
otherwise in the tables.
    NMFS conducted an independent analysis of the mitigation areas that 
the Action Proponent proposed, which are described below. NMFS 
preliminarily concurs with the Action Proponents' analysis, which 
indicates that the measures in these mitigation areas are both 
practicable and will reduce the likelihood, magnitude, or severity of 
adverse impacts to marine mammals or their habitat in the manner 
described in the Action Proponents' analysis and this rule. NMFS is 
heavily reliant on the Action Proponents' description of operational 
practicability, since the Action Proponents are best equipped to 
describe the degree to which a given mitigation measure affects 
personnel safety or mission effectiveness, and is practical to 
implement. The Action Proponents consider the measures in this proposed 
rule to be practicable, and NMFS concurs. We further discuss the manner 
in which the Geographic Mitigation Areas in the proposed rule will 
reduce the likelihood, magnitude, or severity of adverse impacts to 
marine mammal species or their habitat in the Preliminary Analysis and 
Negligible Impact Determination section.
    Table 71 details geographic mitigation related to ship shock 
trials, which involve the use of explosives. Ship shock trials are 
conducted only within established ship shock trial boxes within the 
Gulf of America and overlapping the Jacksonville OPAREA. The boundaries 
of the mitigation areas match the boundaries of each ship shock trial 
box. Mitigation is a continuation of existing measures, except for new 
mitigation related to the location of the northern Gulf of America ship 
shock trial box as described in table 71.

                                   Table 71--Ship Shock Trial Mitigation Area
----------------------------------------------------------------------------------------------------------------
               Category                          Mitigation requirements                Mitigation benefits
----------------------------------------------------------------------------------------------------------------
Explosives...........................  Navy personnel must not conduct ship shock  Prior to being repositioned,
                                        trials within the portion of the ship       the northern Gulf of America
                                        shock trial box that overlaps the           ship shock trial box
                                        Jacksonville OPAREA from November 15        overlapped the Rice's whale
                                        through April 15.                           core distribution area.
                                       Pre-event planning for ship shock trials     Preliminary Navy Acoustic
                                        must include the selection of one primary   Effects Model data indicated
                                        and two secondary sites (within one of      that Rice's whales would
                                        the ship shock trial boxes) where marine    have potentially been
                                        mammal abundance is expected to be the      exposed to AUD INJ, TTS, and
                                        lowest during an event, with the primary    behavioral impacts from
                                        and secondary locations located more than   explosives if events were to
                                        2 nmi (3.7 km) from the western boundary    occur at that location. Navy
                                        of the Gulf Stream for events planned       personnel determined it
                                        within the portion of the ship shock        would be practicable to
                                        trial box that overlaps the Jacksonville    reposition the ship shock
                                        OPAREA.                                     trial box outside of the
                                       If Navy personnel determine during pre-      Rice's whale core
                                        event visual observations that the          distribution area, and into
                                        primary site is environmentally             a new location that would
                                        unsuitable (e.g., continuous observations   avoid potential exposure of
                                        of marine mammals), they would evaluate     Rice's whales to injurious
                                        the potential to move the event to one of   levels of sound. The
                                        the secondary sites in accordance with      repositioned ship shock
                                        the event-specific mitigation and           trial box is now located off
                                        monitoring plan (see table 11.5-2 of the    the Naval Surface Warfare
                                        application for additional information).    Center, Panama City Division
                                                                                    Testing Range's southern
                                                                                    boundary.
                                                                                   Mitigation to not conduct
                                                                                    ship shock trials in the
                                                                                    Jacksonville OPAREA from
                                                                                    November 15 through April 15
                                                                                    is designed to avoid
                                                                                    potential injurious and
                                                                                    behavioral impacts on NARW
                                                                                    during calving season.
                                                                                   Mitigation to consider marine
                                                                                    mammal abundance during pre-
                                                                                    event planning, to
                                                                                    prioritize locations that
                                                                                    are more than 2 nmi (3.7 km)
                                                                                    from the western boundary of
                                                                                    the Gulf Stream (where
                                                                                    marine mammals would be
                                                                                    expected in greater
                                                                                    concentrations for foraging
                                                                                    and migration) when
                                                                                    conducting ship shock trials
                                                                                    in the boxes that overlap
                                                                                    the Jacksonville OPAREA, and
                                                                                    to evaluate the
                                                                                    environmental suitability of
                                                                                    the selected site based on
                                                                                    pre-event observations, are
                                                                                    collectively designed to
                                                                                    reduce the number of
                                                                                    individual marine mammals
                                                                                    exposed, as well as the
                                                                                    level of impact that could
                                                                                    potentially be received by
                                                                                    each animal.

[[Page 19999]]

 
                                       ..........................................  The benefits of the
                                                                                    mitigation for Rice's
                                                                                    whales, NARW, and other
                                                                                    marine mammal species would
                                                                                    be substantial because ship
                                                                                    shock trials use the largest
                                                                                    NEW of any explosive
                                                                                    activity conducted under the
                                                                                    Proposed Action.
----------------------------------------------------------------------------------------------------------------

    Table 72 details geographic mitigation related to MTEs (i.e., 
Composite Training Unit Exercises and Sustainment Exercises). 
Mitigation is a continuation of existing measures.

                      Table 72--Major Training Exercise Planning Awareness Mitigation Area
----------------------------------------------------------------------------------------------------------------
               Category                          Mitigation requirements                Mitigation benefits
----------------------------------------------------------------------------------------------------------------
Acoustic, Explosives, Physical         Northeast: Within Major Training Exercise   Mitigation to prohibit or
 disturbance and strike.                Planning Awareness Mitigation Areas         limit MTEs within regional
                                        located in the Northeast (i.e., the         planning mitigation areas is
                                        combined areas within the Gulf of Maine,    collectively designed to
                                        over the continental shelves off Long       reduce the number of marine
                                        Island, Rhode Island, Massachusetts, and    mammal species, and
                                        Maine), the Action Proponents must not      individuals within each
                                        conduct any full or partial MTEs.           species, that are exposed to
                                       Mid-Atlantic: Within Major Training          potential impacts from
                                        Exercise Planning Awareness Mitigation      active sonar during MTEs.
                                        Areas located in the Mid-Atlantic (i.e.,    The mitigation areas are
                                        the combined areas off Maryland,            situated among highly
                                        Delaware, and North Carolina), the Action   productive environments and
                                        Proponents must avoid conducting any full   persistent oceanographic
                                        or partial MTEs to the maximum extent       features associated with
                                        practical, and must not conduct more than   upwelling, steep bathymetric
                                        four full or partial MTEs per year.         contours, and canyons. The
                                                                                    areas have high marine
                                                                                    mammal densities, abundance,
                                                                                    or concentrated use for
                                                                                    feeding, reproduction, or
                                                                                    migration. Mitigation
                                                                                    benefits would be
                                                                                    substantial because MTEs are
                                                                                    conducted on a larger scale
                                                                                    and with more hours of
                                                                                    active sonar use than other
                                                                                    types of active sonar
                                                                                    events.
                                                                                   Mitigation for the Northeast
                                                                                    planning areas (including in
                                                                                    the Gulf of Maine) is
                                                                                    designed to prevent MTEs
                                                                                    from occurring within NARW
                                                                                    foraging critical habitat,
                                                                                    across the shelf break in
                                                                                    the northeast, on Georges
                                                                                    Bank, and in areas that
                                                                                    contain underwater canyons
                                                                                    (e.g., Hydrographer Canyon).
                                                                                    These locations (including
                                                                                    within a portion of the
                                                                                    Northeast Canyons and
                                                                                    Seamounts National Marine
                                                                                    Monument) have been
                                                                                    associated with high
                                                                                    occurrences of marine mammal
                                                                                    feeding, abundance, or
                                                                                    mating for harbor porpoises
                                                                                    and humpback, minke, sei,
                                                                                    fin, and NARW.
                                       ..........................................  Mitigation for the Mid-
                                                                                    Atlantic planning areas is
                                                                                    designed to limit the number
                                                                                    of MTEs that could occur
                                                                                    within large swaths of shelf
                                                                                    break that contain
                                                                                    underwater canyons or other
                                                                                    habitats (e.g., Norfolk
                                                                                    Canyon, part of the Cape
                                                                                    Hatteras Special Research
                                                                                    Area) associated with high
                                                                                    marine mammal diversity in
                                                                                    this region, including blue,
                                                                                    fin, minke, sei, sperm,
                                                                                    beaked, dwarf sperm, pygmy
                                                                                    sperm, and humpback whales,
                                                                                    as well as Risso's dolphins
                                                                                    and other delphinid species.
                                                                                    The planning areas also
                                                                                    overlap NARW migration
                                                                                    habitats.
----------------------------------------------------------------------------------------------------------------

    Table 73 details geographic mitigation related to active sonar and 
explosives (and special reporting for their use), and physical 
disturbance and strike stressors off the northeastern United States. 
The mitigation area extent matches that of the NARW foraging critical 
habitat designated in 2016 (81 FR 4838, February 26, 2016). Mitigation 
is a continuation of existing measures, with clarification that 
requirements pertain to in-water stressors (i.e., not activities with 
no potential marine mammal impacts, such as air-to-air activities). 
Mitigation is designed to protect individual NARW within their foraging 
critical habitat. Mitigation will also protect individuals of other 
species whose biologically significant habitats overlap the mitigation 
area, including harbor porpoises and humpback, minke, sei, and fin 
whales. Special reporting for the use of acoustics and explosives is 
also required for this area (see Proposed Reporting section for 
details).

                         Table 73--Northeast North Atlantic Right Whale Mitigation Area
----------------------------------------------------------------------------------------------------------------
               Category                          Mitigation requirements                Mitigation benefits
----------------------------------------------------------------------------------------------------------------
Acoustic.............................  The Action Proponents must minimize the     Mitigation is designed to
                                        use of low-frequency active sonar, mid-     minimize exposure of NARW to
                                        frequency active sonar, and high-           sounds with potential for
                                        frequency active sonar in the mitigation    injury or behavioral
                                        area to the maximum extent practical.       impacts.
Explosives...........................  The Action Proponents must not detonate in- Mitigation is designed to
                                        water explosives (including underwater      prevent exposure of NARW to
                                        explosives and explosives deployed          explosives with potential
                                        against surface targets) within the         for injury, mortality, or
                                        mitigation area.                            behavioral impacts.
                                       The Action Proponents must not detonate     Mitigation to prohibit
                                        explosive sonobuoys within 3 nmi (5.6 km)   explosive sonobuoys within 3
                                        of the mitigation area.                     nmi (5.6 km) is designed to
                                                                                    further prevent exposure to
                                                                                    large and dispersed
                                                                                    explosive sonobuoy fields.

[[Page 20000]]

 
Physical disturbance and strike......  The Action Proponents must not use non-     Mitigation to prohibit use of
                                        explosive bombs within the mitigation       non-explosive bombs is
                                        area.                                       designed to reduce the
                                       During non-explosive torpedoes events        potential for NARW to be
                                        within the mitigation area:                 struck by non-explosive
                                       --The Action Proponents must conduct         ordnance.
                                        activities during daylight hours in        Mitigation to conduct non-
                                        Beaufort sea state 3 or less.               explosive torpedo activities
                                       --In addition to Lookouts required as        during daylight hours in
                                        described in section 11.5 of the            Beaufort sea state 3 or
                                        application, the Action Proponents must     less, and to post additional
                                        post two Lookouts in an aircraft during     Lookouts from aircraft (and
                                        dedicated aerial surveys, and one Lookout   submarines, when surfaced),
                                        on the submarine participating in the       is designed to improve
                                        event (when surfaced). Lookouts must        marine mammal sightability
                                        begin conducting visual observations        during visual observations.
                                        immediately prior to the start of an       Mitigation for vessels to
                                        event. If floating vegetation or marine     obtain sightings information
                                        mammals are observed in the event           from the North Atlantic
                                        vicinity, the event must not commence       Right Whale Sighting
                                        until the vicinity is clear or the event    Advisory System and
                                        is relocated to an area where the           implement speed reductions
                                        vicinity is clear. Lookouts must continue   in certain circumstances is
                                        to conduct visual observations during the   designed to reduce the
                                        event. If marine mammals are observed in    potential for vessels to
                                        the vicinity, the event must cease until    encounter NARW. The North
                                        one of the Mitigation Zone All-Clear        Atlantic Right Whale
                                        Conditions has been met as described in     Sighting Advisory System is
                                        section 11.5 of the application.            a NOAA Northeast Fisheries
                                       --During transits and normal firing,         Science Center program that
                                        surface ships must maintain a speed of no   collects sightings
                                        more than 10 kn (18.5 km/hr); during        information off the
                                        submarine target firing, surface ships      northeastern United States
                                        must maintain speeds of no more than 18     from aerial surveys,
                                        kn (33.3 km/hr); and during vessel target   shipboard surveys, whale
                                        firing, surface ship speeds may exceed 18   watching vessels, and
                                        kn (33.3 km/hr) for brief periods of time   opportunistic sources, such
                                        (e.g., 10-15 minutes).                      as the Coast Guard,
                                                                                    commercial ships, fishing
                                                                                    vessels, and the public.
                                       For vessel transits within the mitigation
                                        area:
                                       --The Action Proponents must conduct a web
                                        query or e-mail inquiry to the North
                                        Atlantic Right Whale Sighting Advisory
                                        System or WhaleMap (https://whalemap.org/
                                        ) to obtain the latest NARW sightings
                                        data prior to transiting the mitigation
                                        area. The Action Proponents must provide
                                        Lookouts the sightings data prior to
                                        standing watch. Lookouts must use that
                                        data to help inform visual observations
                                        during vessel transits.
                                       Surface ships must implement speed
                                        reductions after observing a NARW, if
                                        transiting within 5 nmi (9.3 km) of a
                                        sighting reported to the North Atlantic
                                        Right Whale Sighting Advisory System
                                        within the past week, and when transiting
                                        at night or during periods of reduced
                                        visibility.
----------------------------------------------------------------------------------------------------------------

    Table 74 details geographic mitigation related to active sonar and 
special reporting for the use of active sonar and in-water explosives 
within the Gulf of Maine. Mitigation is a continuation of existing 
measures. Special reporting for the use of acoustics and explosives is 
also required for this area (see Proposed Reporting section for 
details).

                              Table 74--Gulf of Maine Marine Mammal Mitigation Area
----------------------------------------------------------------------------------------------------------------
               Category                          Mitigation requirements                Mitigation benefits
----------------------------------------------------------------------------------------------------------------
Acoustic.............................  The Action Proponents must not use more     Mitigation is designed to
                                        than 200 hours of surface ship hull-        reduce exposure of NARW to
                                        mounted mid-frequency active sonar          potentially injurious levels
                                        annually within the mitigation area.        of sound from the type of
                                                                                    active sonar with the
                                                                                    highest source power used in
                                                                                    the Study Area within
                                                                                    foraging critical habitat
                                                                                    designated by NMFS in 2016
                                                                                    (81 FR 4838, February 26,
                                                                                    2016) and additional sea
                                                                                    space southward over Georges
                                                                                    Bank.
----------------------------------------------------------------------------------------------------------------

    Table 75 details geographic mitigation related to active sonar and 
explosives (and special reporting for their use), and physical 
disturbance and strike stressors in the Jacksonville OPAREA. Mitigation 
is a continuation of existing measures, with clarification that 
requirements pertain to in-water stressors (i.e., not activities with 
no potential marine mammal impacts, such as air-to-air activities).

                Table 75--Jacksonville Operating Area North Atlantic Right Whale Mitigation Area
----------------------------------------------------------------------------------------------------------------
               Category                          Mitigation requirements                Mitigation benefits
----------------------------------------------------------------------------------------------------------------
Acoustic, explosives, and physical     From November 15 to April 15 within the     Mitigation is designed to
 disturbance and vessel strike.         mitigation area, prior to vessel transits   minimize potential NARW-
                                        or military readiness activities            vessel interactions and
                                        involving active sonar, in-water            exposure to stressors with
                                        explosives (including underwater            the potential for mortality,
                                        explosives and explosives deployed          injury, or behavioral
                                        against surface targets), or non-           disturbance within the
                                        explosive ordnance deployed against         portions of the reproduction
                                        surface targets (including aerial-          (calving) critical habitat
                                        deployed mines), the Action Proponents      designated by NMFS in 2016
                                        must initiate communication with Fleet      (81 FR 4838) and important
                                        Area Control and Surveillance Facility,     migration habitat that
                                        Jacksonville to obtain Early Warning        overlaps the Jacksonville
                                        System data. The facility must advise of    OPAREA.
                                        all reported NARW sightings in the         The benefits of the
                                        vicinity of planned vessel transits and     mitigation would be
                                        military readiness activities.              substantial because the
                                       --Sightings data must be used when           Jacksonville OPAREA is an
                                        planning event details (e.g., timing,       Action Proponent
                                        location, duration) to minimize             concentration area within
                                        interactions with NARW to the maximum       the southeastern region.
                                        extent practical.

[[Page 20001]]

 
                                       The Action Proponents must provide
                                        Lookouts the sightings data prior to
                                        standing watch to help inform visual
                                        observations.
----------------------------------------------------------------------------------------------------------------

    Table 76 details geographic mitigation related to active sonar and 
explosives (and special reporting for their use), and physical 
disturbance and strike stressors off the Southeastern U.S. Mitigation 
is a continuation of existing measures, with clarification that 
requirements pertain to the use of in-water stressors (i.e., not 
activities with no potential marine mammal impacts, such as air-to-air 
activities). The mitigation area is the largest area practical to 
implement within the NARW reproduction critical habitat designated by 
NMFS in 2016 (81 FR 4838). Mitigation is designed to protect 
reproductive mothers, calves, and mother-calf pairs within the only 
known NARW calving habitat. Mitigation benefits would be substantial 
because the mitigation area encompasses the Georgia and northeastern 
Florida coastlines (where the highest seasonal concentrations occur) 
and coastal extent of the Jacksonville OPAREA (an Action Proponent 
concentration area). Special reporting for the use of acoustics and 
explosives is also required for this area (see Proposed Reporting 
section for details).

                         Table 76--Southeast North Atlantic Right Whale Mitigation Area
----------------------------------------------------------------------------------------------------------------
               Category                          Mitigation requirements                Mitigation benefits
----------------------------------------------------------------------------------------------------------------
Acoustic.............................  From November 15 to April 15 within the     Mitigation is designed to
                                        mitigation area, the Action Proponents      minimize exposure to levels
                                        must not use high-frequency active sonar;   of sound that have the
                                        or low-frequency or mid-frequency active    potential to cause injurious
                                        sonar except:                               or behavioral impacts.
                                       --To the maximum extent practical, the
                                        Action Proponents must minimize use of
                                        (1) helicopter dipping sonar (a mid-
                                        frequency active sonar source) and (2)
                                        low-frequency or surface ship hull-
                                        mounted mid-frequency active sonar during
                                        navigation training or object detection.
Explosives...........................  From November 15 to April 15 within the     Mitigation is designed to
                                        mitigation area, the Action Proponents      prevent exposure to
                                        must not detonate in-water explosives       explosives with the
                                        (including underwater explosives and        potential for injury,
                                        explosives deployed against surface         mortality, or behavioral
                                        targets).                                   disturbance.
Physical disturbance and vessel        From November 15 to April 15 within the     Mitigation is designed to
 strike.                                mitigation area, the Action Proponents      prevent strikes by non-
                                        must not deploy non-explosive ordnance      explosive ordnance, and to
                                        against surface targets (including aerial-  decrease the potential for
                                        deployed mines).                            vessel strikes. North-south
                                       From November 15 to April 15 within the      transit restrictions are
                                        mitigation area, surface ships must         designed to reduce the time
                                        minimize north-south transits to the        ships spend in the highest
                                        maximum extent practical, and must          seasonal occurrence areas to
                                        implement speed reductions after they       further decrease vessel
                                        observe a NARW, if they are within 5 nmi    strike risk.
                                        (9.3 km) of an Early Warning System
                                        sighting reported within the past 12
                                        hours, and at night and in poor
                                        visibility.
Acoustic, explosives, and physical     From November 15 to April 15 within the     Mitigation is designed to
 disturbance and vessel strike.         mitigation area, prior to vessel transits   minimize potential vessel
                                        or military readiness activities            interactions and exposure to
                                        involving active sonar, in-water            stressors with the potential
                                        explosives (including underwater            for mortality, injury, or
                                        explosives and explosives deployed          behavioral disturbance.
                                        against surface targets), or non-
                                        explosive ordnance deployed against
                                        surface targets (including aerial-
                                        deployed mines), the Action Proponents
                                        must initiate communication with Fleet
                                        Area Control and Surveillance Facility,
                                        Jacksonville to obtain Early Warning
                                        System sightings data. The facility must
                                        advise of all reported NARW sightings in
                                        the vicinity of planned vessel transits
                                        and military readiness activities.
                                       The Action Proponents must provide
                                        Lookouts the sightings data prior to
                                        standing watch to help inform visual
                                        observations.
----------------------------------------------------------------------------------------------------------------

    Table 77 details geographic mitigation related to active sonar, 
explosives, and physical disturbance and strike stressors off the U.S. 
east coast to the boundary of the U.S. EEZ. Mitigation is a 
continuation of existing measures, with clarification that requirements 
pertain to the use of in-water stressors (i.e., not activities with no 
potential marine mammal impacts, such as air-to-air activities).

                          Table 77--Dynamic North Atlantic Right Whale Mitigation Areas
----------------------------------------------------------------------------------------------------------------
               Category                          Mitigation requirements                Mitigation benefits
----------------------------------------------------------------------------------------------------------------
Acoustic, explosives, and physical     The applicable dates and locations of this  The mitigation area extent
 disturbance and vessel strike.         mitigation area must correspond with        matches the boundary of the
                                        NMFS' Dynamic Management Areas, which       U.S. EEZ on the East Coast,
                                        fluctuate throughout the year based on      which is the full extent of
                                        the locations and timing of confirmed       where Dynamic Management
                                        NARW detections.                            Areas could potentially be
                                       The Action Proponents must provide NARW      established year-round. NMFS
                                        Dynamic Management Area information         manages the Dynamic
                                        (e.g., location and dates) to applicable    Management Areas program off
                                        assets transiting and training or testing   the U.S. East Coast with the
                                        in the vicinity of the Dynamic Management   primary goal of reducing the
                                        Area.                                       likelihood of NARW vessel
                                       --The broadcast awareness notification       strikes from all mariners.
                                        messages must alert assets (and their      Mitigation is designed to
                                        Lookouts) to the possible presence of       minimize potential NARW
                                        NARW in their vicinity.                     vessel interactions and
                                                                                    exposure to acoustic
                                                                                    stressors, explosives, and
                                                                                    physical disturbance and
                                                                                    strike stressors that have
                                                                                    the potential to cause
                                                                                    mortality, injury, or
                                                                                    behavioral disturbance.

[[Page 20002]]

 
                                       Lookouts must use the information to help
                                        inform visual observations during
                                        military readiness activities that
                                        involve vessel movements, active sonar,
                                        in-water explosives (including underwater
                                        explosives and explosives deployed
                                        against surface targets), or non-
                                        explosive ordnance deployed against
                                        surface targets in the mitigation area.
----------------------------------------------------------------------------------------------------------------

    Table 78 details geographic mitigation related to active sonar and 
explosives (and special reporting for their use) in the northeastern 
Gulf of America. Mitigation is a continuation of existing measures. The 
mitigation area extent aligns with this species' small and resident 
population area identified by NMFS in its 2016 status review (Rosel et 
al., 2016). Special reporting for the use of acoustics and explosives 
is also required for this area (see Proposed Reporting section for 
details).

                                     Table 78--Rice's Whale Mitigation Area
----------------------------------------------------------------------------------------------------------------
               Category                          Mitigation requirements                Mitigation benefits
----------------------------------------------------------------------------------------------------------------
Acoustic.............................  The Action Proponents must not use more     Mitigation is designed to
                                        than 200 hours of surface ship hull-        reduce exposure of
                                        mounted mid-frequency active sonar          individuals within the small
                                        annually within the mitigation area.        and resident population of
                                                                                    Rice's whales to potentially
                                                                                    injurious levels of sound by
                                                                                    the type of active sonar
                                                                                    with the highest source
                                                                                    power used in the Study
                                                                                    Area.
Explosives...........................  Except during mine warfare activities, the  Mitigation is designed to
                                        Action Proponents must not detonate in-     reduce exposure of
                                        water explosives (including underwater      individuals within the small
                                        explosives and explosives deployed          and resident population of
                                        against surface targets) within the         Rice's whales to explosives
                                        mitigation area.                            that have the potential to
                                                                                    cause injury, mortality, or
                                                                                    behavioral disturbance.
----------------------------------------------------------------------------------------------------------------

Mitigation Conclusions

    NMFS has carefully evaluated the Action Proponents' proposed 
mitigation measures--many of which were developed with NMFS' input 
during the previous phases of AFTT authorizations but several of which 
are new since implementation of the 2018 to 2025 regulations--and 
considered a broad range of other measures (i.e., the measures 
considered but eliminated in the 2018 AFTT Final EIS/OEIS, which 
reflect many of the comments that have arisen from public input or 
through discussion with NMFS in past years) in the context of ensuring 
that NMFS prescribes the means of effecting the least practicable 
adverse impact on the affected marine mammal species and their habitat. 
Our evaluation of potential measures included consideration of the 
following factors in relation to one another: the manner in which, and 
the degree to which, the successful implementation of the mitigation 
measures is expected to reduce the likelihood and/or magnitude of 
adverse impacts to marine mammal species and their habitat; the proven 
or likely efficacy of the measures; and the practicability of the 
measures for applicant implementation, including consideration of 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.
    Based on our evaluation of the Action Proponents' proposed 
measures, as well as other measures considered by the Action Proponents 
and NMFS (see section 5.9 (Measures Considered but Eliminated) of 
chapter 5 (Mitigation) of the 2024 AFTT Draft Supplemental EIS/OEIS), 
NMFS has preliminarily determined that these proposed mitigation 
measures are appropriate means of effecting the least practicable 
adverse impact on marine mammal species and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and considering specifically personnel safety, 
practicality of implementation, and impact on the effectiveness of the 
military readiness activity. Additionally, an adaptive management 
component helps further ensure that mitigation is regularly assessed 
and provides a mechanism to improve the mitigation, based on the 
factors above, through modification as appropriate.
    The proposed rule comment period provides the public an opportunity 
to submit recommendations, views, and/or concerns regarding the Action 
Proponents' activities and the proposed mitigation measures. While NMFS 
has preliminarily determined that the Action Proponents' proposed 
mitigation measures would effect the least practicable adverse impact 
on the affected species and their habitat, NMFS will consider all 
public comments to help inform our final determination. Consequently, 
proposed mitigation measures may be refined, modified, removed, or 
added prior to the issuance of the final rule based on public comments 
received and, as appropriate, analysis of additional potential 
mitigation measures.

Proposed Monitoring

    Section 101(a)(5)(A) of the MMPA states that in order to authorize 
incidental take for an activity, NMFS must set forth requirements 
pertaining to the monitoring and reporting of such taking. The MMPA 
implementing regulations at 50 CFR 216.104(a)(13) indicate that 
requests for incidental take authorizations must include the suggested 
means of accomplishing the necessary monitoring and reporting that will 
result in increased knowledge of the species and of the level of taking 
or impacts on populations of marine mammals that are expected to be 
present.
    Although the Navy has been conducting research and monitoring for 
over 20 years in areas where it has been training, it developed a 
formal marine species monitoring program in support of the AFTT Study 
Area MMPA and ESA processes in 2009. Across all Navy training and 
testing study areas, the robust marine species monitoring program has 
resulted in hundreds of technical reports and publications on marine 
mammals that have informed Navy and NMFS analyses in environmental 
planning documents, rules, and Biological Opinions. The reports are 
made available to the public on the Navy's marine species monitoring 
website (www.navymarinespeciesmonitoring.us) and the data on the Ocean 
Biogeographic Information System

[[Page 20003]]

Spatial Ecological Analysis of Megavertebrate Populations (OBIS-SEAMAP) 
(https://seamap.env.duke.edu/).
    The Navy would continue collecting monitoring data to inform our 
understanding of the occurrence of marine mammals in the AFTT Study 
Area; the likely exposure of marine mammals to stressors of concern in 
the AFTT Study Area; the response of marine mammals to exposures to 
stressors; the consequences of a particular marine mammal response to 
their individual fitness and, ultimately, populations; and the 
effectiveness of implemented mitigation measures. Taken together, 
mitigation and monitoring comprise the Navy's integrated approach for 
reducing environmental impacts from the specified activities. The 
Navy's overall monitoring approach seeks to leverage and build on 
existing research efforts whenever possible.
    As agreed upon between the Action Proponents and NMFS, the 
monitoring measures presented here, as well as the mitigation measures 
described above, focus on the protection and management of potentially 
affected marine mammals. A well-designed monitoring program can provide 
important feedback for validating assumptions made in analyses and 
allow for adaptive management of marine mammals and their habitat, and 
other marine resources. Monitoring is required under the MMPA, and 
details of the monitoring program for the specified activities have 
been developed through coordination between NMFS and the Action 
Proponents through the regulatory process for previous Navy at-sea 
training and testing activities.

Navy Marine Species Research and Monitoring Strategic Framework

    The initial structure for the U.S. Navy's marine species monitoring 
efforts was developed in 2009 with the Integrated Comprehensive 
Monitoring Program (ICMP). The intent of the ICMP was to provide an 
overarching framework for coordination of the Navy's monitoring efforts 
during the early years of the program's establishment. A Strategic 
Planning Process (U.S. Department of the Navy, 2013) was subsequently 
developed and together with the ICMP framework serves as a planning 
tool to focus marine species monitoring priorities defined by ESA and 
MMPA requirements, and to coordinate monitoring efforts across regions 
based on a set of common objectives. Using an underlying conceptual 
framework incorporating a progression of knowledge from occurrence to 
exposure/response, and ultimately consequences, the Strategic Planning 
Process was developed as a tool to help guide the investment of 
resources to address top level objectives and goals of the monitoring 
program most efficiently. The Strategic Planning Process identifies 
Intermediate Scientific Objectives, which form the basis of evaluating, 
prioritizing, and selecting new monitoring projects or investment 
topics and serve as the basis for developing and executing new 
monitoring projects across the Navy's training and testing ranges (both 
Atlantic and Pacific).
    Monitoring activities relating to the effects of military readiness 
activities on marine species are generally designed address one or more 
of the following top-level goals:
    (i) An increase in the understanding of the likely occurrence of 
marine mammals and ESA-listed marine species in the vicinity of the 
action (i.e., presence, abundance, distribution, and density);
    (ii) An increase in the understanding of the nature, scope, or 
context of the likely exposure of marine mammals and ESA-listed species 
to any of the potential stressors associated with the action (e.g., 
sound, explosive detonation, or military expended materials), through 
better understanding of one or more of the following:
    A. The nature of the action and its surrounding environment (e.g., 
sound-source characterization, propagation, and ambient noise levels),
    B. The affected species (e.g., life history or dive patterns),
    C. The likely co-occurrence of marine mammals and ESA-listed marine 
species with the action (in whole or part), or
    D. The likely biological or behavioral context of exposure to the 
stressor for the marine mammal and ESA-listed marine species (e.g., age 
class of exposed animals or known pupping, calving, or feeding areas).
    (iii) An increase in the understanding of how individual marine 
mammals or ESA-listed marine species respond (behaviorally or 
physiologically) to the specific stressors associated with the action 
(in specific contexts, where possible (e.g., at what distance or 
received level)).
    (iv) An increase in the understanding of how anticipated individual 
responses, to individual stressors or anticipated combinations of 
stressors, may impact either:
    A. The long-term fitness and survival of an individual; or
    B. The population, species, or stock (e.g., through impacts on 
annual rates of recruitment or survival).
    (v) An increase in the understanding of the effectiveness of 
mitigation and monitoring measures.
    (vi) A better understanding and record of the manner in which the 
authorized entity complies with the Incidental Take Authorization and 
Incidental Take Statement.
    (vii) An increase in the probability of detecting marine mammals 
(through improved technology or methods), both specifically within the 
mitigation zone (thus allowing for more effective implementation of the 
mitigation) and in general, to better achieve the above goals; and
    (viii) Ensuring that adverse impact of activities remains at the 
least practicable level.
    The Navy's Marine Species Monitoring Program investments are 
evaluated through the Adaptive Management Review process to (1) assess 
overall progress, (2) review goals and objectives, and (3) make 
recommendations for refinement and evolution of the monitoring 
program's focus and direction. The Marine Species Monitoring Program 
has developed and matured significantly since its inception and now 
supports a portfolio of several dozen active projects across a range of 
geographic areas and protected species taxa addressing both regional 
priorities (i.e., particular species of concern), and Navy-wide needs 
such as the behavioral response of beaked whales to training and 
testing activities.
    A Research and Monitoring Summit was held in early 2023 to evaluate 
the current state of the Marine Species Monitoring Program in terms of 
progress, objectives, priorities, and needs, and to solicit valuable 
input from meeting participants including NMFS, Marine Mammal 
Commission, Navy, and scientific experts. The overarching goal of the 
summit was to facilitate updating the ICMP framework for guiding marine 
species research and monitoring investments, and to identify data gaps 
and priorities to be addressed over the next 5-10 years across a range 
of basic research through applied monitoring. One of the outcomes of 
this summit meeting is a refreshed strategic framework effectively 
replacing the ICMP which will provide increased coordination and 
synergy across the Navy's protected marine species investment programs 
(see section 13.1 of the application). This will contribute to the 
collective goal of supporting improved assessment of effects from 
training and testing activities through

[[Page 20004]]

development of first in class science and data.

Past and Current Action Proponent Monitoring in the AFTT Study Area

    The Navy's monitoring program has undergone significant changes 
since the first rule was issued for the AFTT Study Area in 2008 through 
the process of adaptive management. The monitoring program developed 
for the first cycle of environmental compliance documents (e.g., U.S. 
Department of the Navy, 2008a, 2008b) utilized effort-based compliance 
metrics that were somewhat limiting. Through adaptive management 
discussions, the Navy designed and conducted monitoring studies 
according to scientific objectives and eliminated specific effort 
requirements.
    Progress has also been made on the conceptual framework categories 
from the Scientific Advisory Group for Navy Marine Species Monitoring 
(U.S. Department of the Navy, 2011), ranging from occurrence of 
animals, to their exposure, response, and population consequences. The 
Navy continues to manage the Atlantic and Pacific program as a whole, 
with monitoring in each range complex taking a slightly different but 
complementary approach. The Navy has continued to use the approach of 
layering multiple simultaneous components in many of the range 
complexes to leverage an increase in return of the progress toward 
answering scientific monitoring questions. This includes in the AFTT 
Study Area, for example, (a) Analysis of Acoustic Ecology of North 
Atlantic Shelf Break Cetaceans and Effects of Anthropogenic Noise 
Impacts; (b) Mid-Atlantic Nearshore and Mid-shelf Baleen Whale 
Monitoring; (c) Atlantic Behavioral Response Study; and (d) Occurrence 
of Rice's Whale in the Northeastern Gulf of America.
    Numerous publications, dissertations, and conference presentations 
have resulted from research conducted under the marine species 
monitoring program (https://www.navymarinespeciesmonitoring.us/reading-room/), leading to a significant contribution to the body of marine 
mammal science. Publications on occurrence, distribution, and density 
have fed the modeling input, and publications on exposure and response 
have informed Navy and NMFS analysis of behavioral response and 
consideration of mitigation measures.
    Furthermore, collaboration between the monitoring program and the 
Navy's research and development (e.g., the ONR) and demonstration-
validation (e.g., Living Marine Resources (LMR)) programs has been 
strengthened, leading to research tools and products that have already 
transitioned to the monitoring program. These include Marine Mammal 
Monitoring on Ranges, controlled exposure experiment behavioral 
response studies, acoustic sea glider surveys, and global positioning 
system-enabled satellite tags. Recent progress has been made with 
better integration with monitoring across all Navy at-sea study areas, 
including the AFTT Study Area and various other ranges. Publications 
from the LMR and ONR programs have also resulted in significant 
contributions to hearing, acoustic criteria used in effects modeling, 
exposure, and response, as well as in developing tools to assess 
biological significance (e.g., consequences).
    NMFS and the Navy also consider data collected during mitigations 
as monitoring. Data are collected by shipboard personnel on hours spent 
training, hours of observation, hours of sonar, and marine mammals 
observed within the mitigation zones when mitigations are implemented. 
These data are provided to NMFS in both classified and unclassified 
annual exercise reports, which would continue under this proposed rule.
    NMFS has received multiple years' worth of annual exercise and 
monitoring reports addressing active sonar use and explosive 
detonations within the AFTT Study Area and other Navy range complexes. 
The data and information contained in these reports have been 
considered in developing mitigation and monitoring measures for the 
proposed military readiness activities within the AFTT Study Area. The 
Navy's annual exercise and monitoring reports may be viewed at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities and https://www.navymarinespeciesmonitoring.us/reporting/.
    The Navy's marine species monitoring program supports several 
monitoring projects in the AFTT Study Area at any given time. 
Additional details on the scientific objectives for each project can be 
found at: https://www.navymarinespeciesmonitoring.us/regions/atlantic/current-projects/. Projects can be either major multi-year efforts, or 
1 to 2-year special studies. The emphasis on monitoring in the AFTT 
Study Area is to improve understanding of the occurrence and 
distribution of protected marine species within the AFTT Study Area, 
improve understanding of their exposure and response to sonar and 
explosives training and testing activities, and ultimately inform 
decision makers of the consequences of that exposure.
    Specific monitoring under the 2018-2025 regulations included the 
following projects:
    (i) Atlantic Behavioral Response Study;
    (ii) Behavioral Response Analysis of Two Populations of Short-
Finned Pilot Whales to Mid-Frequency Active Sonar;
    (iii) Behavioral Response of Humpback Whales to Vessel Traffic;
    (iv) Analysis of Acoustic Ecology of North Atlantic Shelf Break 
Cetaceans and Effects of Anthropogenic Noise Impacts;
    (v) North Atlantic Right Whale Monitoring, Conservation, and 
Protection;
    (vi) Atlantic Marine Assessment Program for Protected Species 
(AMAPPS);
    (vii) Haul-Out Counts and Photo-Identification of Pinnipeds in 
Virginia;
    (viii) Time-lapse Camera Surveys of Pinnipeds in Southeastern 
Virginia;
    (ix) Pinniped Monitoring in the Northeast;
    (x) Jacksonville Shallow Water Training Range Vessel Surveys;
    (xi) Mid-Atlantic Autonomous Passive Acoustic Monitoring;
    (xii) Mid-Atlantic Nearshore & Mid-shelf Baleen Whale Monitoring;
    (xiii) Mid-Atlantic Offshore Cetacean Study; and
    (xiv) Occurrence of Rice's Whale in the Northeastern Gulf of 
America.
    Future monitoring efforts by the Action Proponents in the AFTT 
Study Area are anticipated to continue along the same objectives: 
establish the baseline habitat uses and movement patterns; establish 
the baseline behavior (foraging, dive patterns, etc.); evaluate 
potential exposure and behavioral responses of marine mammals exposed 
to training and testing activities, and support conservation and 
management of NARWs.
    Currently planned monitoring projects and their Intermediate 
Scientific Objective for the 2025-2032 rule are listed below, many of 
which are continuations of projects currently underway. Other than 
those ongoing projects, monitoring projects are typically planned one 
year in advance; therefore, this list does not include all projects 
that will occur over the entire period of the rule.
    (i) Atlantic Behavioral Response Study (ongoing)--The objective is 
to evaluate behavioral responses of marine mammals exposed to Navy 
training and testing activities.
    (ii) Behavioral Response Analysis of Two Populations of Short-
Finned Pilot Whales to Mid-Frequency Active Sonar

[[Page 20005]]

(ongoing)--The objective is to evaluate behavioral responses of marine 
mammals exposed to Navy training and testing activities.
    (iii) Analysis of Acoustic Ecology of North Atlantic Shelf Break 
Cetaceans and Effects of Anthropogenic Noise Impacts (ongoing)--The 
objectives are to (1) establish the baseline vocalization behavior of 
marine mammals where Navy training and testing activities occur; and 
(2) evaluate trends in distribution and abundance of populations that 
are regularly exposed to sonar and underwater explosives.
    (iv) North Atlantic Right Whale Monitoring, Conservation, and 
Protection (ongoing)--The objectives are to (1) Establish the baseline 
habitat uses and movement patterns of marine mammals where Navy 
training and testing activities occur; and (2) establish the baseline 
behavior (foraging, dive patterns, etc.) of marine mammals where Navy 
training and testing activities occur.
    (v) Haul-Out Counts and Photo-Identification of Pinnipeds in 
Virginia (ongoing)--The objectives are to (1) estimate the density of 
marine mammals and sea turtles in Navy range complexes and in specific 
training areas; (2) establish the baseline habitat uses and movement 
patterns of marine mammals and sea turtles where Navy training and 
testing activities occur; and (3) evaluate trends in distribution and 
abundance of populations that are regularly exposed to sonar and 
underwater explosives.
    (vi) Time-lapse Camera Surveys of Pinnipeds in Southeastern 
Virginia (ongoing)--The objectives are to (1) estimate the density of 
marine mammals and sea turtles in Navy range complexes and in specific 
training areas; (2) establish the baseline habitat uses and movement 
patterns of marine mammals and sea turtles where Navy training and 
testing activities occur; and (3) evaluate trends in distribution and 
abundance of populations that are regularly exposed to sonar and 
underwater explosives.
    (vii) Jacksonville Shallow Water Training Range Vessel Surveys 
(ongoing)--The objectives are to (1) establish the baseline habitat 
uses and movement patterns of marine mammals and sea turtles where Navy 
training and testing activities occur; (2) determine what populations 
of marine mammals are exposed to Navy training and testing activities; 
and (3) evaluate trends in distribution and abundance of populations 
that are regularly exposed to Navy training and testing activities.
    (viii) Mid-Atlantic Autonomous Passive Acoustic Monitoring 
(ongoing)--The objectives are to (1) establish the baseline habitat 
uses and movement patterns of marine mammals where Navy training and 
testing activities occur; and (2) establish the baseline behavior 
(foraging, dive patterns, etc.) of marine mammals where Navy training 
and testing activities occur.
    (ix) Mid-Atlantic Nearshore & Mid-shelf Baleen Whale Monitoring 
(ongoing)--The objectives are to (1) establish the baseline habitat 
uses and movement patterns of marine mammals where Navy training and 
testing activities occur; (2) establish the baseline behavior 
(foraging, dive patterns, etc.) of marine mammals where Navy training 
and testing activities occur; and (3) support conservation and 
management of North Atlantic right whales.
    (x) Mid-Atlantic Offshore Cetacean Study (ongoing)--The objectives 
are to (1) establish the baseline habitat uses and movement patterns of 
marine mammals where Navy training and testing activities occur; and 
(2) establish the baseline behavior (foraging, dive patterns, etc.) of 
marine mammals where Navy training and testing activities occur.

Adaptive Management

    The proposed regulations governing the take of marine mammals 
incidental to military readiness activities in the AFTT Study Area 
contain an adaptive management component. Our understanding of the 
effects of military readiness activities (e.g., acoustic and explosive 
stressors) on marine mammals continues to evolve, which makes the 
inclusion of an adaptive management component both valuable and 
necessary within the context of 7-year regulations.
    The reporting requirements associated with this rule are designed 
to provide NMFS with monitoring data from the previous year to allow 
NMFS to consider whether any changes to existing mitigation and 
monitoring requirements are appropriate. The use of adaptive management 
allows NMFS to consider new information from different sources to 
determine (with input from the Action Proponents regarding 
practicability) on an annual or biennial basis if mitigation or 
monitoring measures should be modified (including additions or 
deletions). Mitigation measures could be modified if new data suggests 
that such modifications would have a reasonable likelihood of more 
effectively accomplishing the goals of the mitigation and monitoring 
and if the measures are practicable. If the modifications to the 
mitigation, monitoring, or reporting measures are substantial, NMFS 
would publish a notice of the planned LOAs in the Federal Register and 
solicit public comment.
    The following are some of the possible sources of applicable data 
to be considered through the adaptive management process: (1) Results 
from monitoring and exercise reports, as required by MMPA 
authorizations; (2) compiled results of Navy-funded research and 
development studies; (3) results from specific stranding 
investigations; (4) results from general marine mammal and sound 
research; and (5) any information which reveals that marine mammals may 
have been taken in a manner, extent, or number not authorized by these 
regulations or subsequent LOAs. The results from monitoring reports and 
other studies may be viewed at https://www.navymarinespeciesmonitoring.us.

Proposed Reporting

    In order to issue incidental take authorization for an activity, 
section 101(a)(5)(A) of the MMPA states that NMFS must set forth 
requirements pertaining to the monitoring and reporting of such taking. 
Effective reporting is critical both to compliance as well as ensuring 
that the most value is obtained from the required monitoring. Reports 
from individual monitoring events, results of analyses, publications, 
and periodic progress reports for specific monitoring projects will be 
posted to the Navy's Marine Species Monitoring web portal: https://www.navymarinespeciesmonitoring.us.
    There are several different reporting requirements for the Navy 
pursuant to the current regulations. All of these reporting 
requirements would be continued for the Navy under this proposed rule 
for the 7-year period.

Special Reporting for Geographic Mitigation Areas

    The following sections describe special reporting for geographic 
mitigation areas that the Action Proponents must include in the Annual 
AFTT Training and Testing Reports. Special reporting for these areas is 
designed to aid the Action Proponents and NMFS in continuing to analyze 
potential impacts of training and testing in the mitigation areas. In 
addition to the mitigation area-specific requirements described below, 
for all mitigation areas, should national security require the Action 
Proponents to exceed the activity restrictions in a given mitigation 
area, Action Proponent personnel must provide NMFS with advance 
notification and include the information (e.g., sonar hours, explosives 
usage, or restricted area use)

[[Page 20006]]

in its annual activity reports submitted to NMFS.
Northeast North Atlantic Right Whale Mitigation Area
    The Action Proponents must report the total annual hours and counts 
of active sonar and in-water explosives (including underwater 
explosives and explosives deployed against surface targets) used in the 
mitigation area.
Gulf of Maine Marine Mammal Mitigation Area
    The Action Proponents must report the total annual hours and counts 
of active sonar and in-water explosives (including underwater 
explosives and explosives deployed against surface targets) used in the 
mitigation area.
Southeast North Atlantic Right Whale Mitigation Area
    The Action Proponents must report the total annual hours and counts 
of active sonar and in-water explosives (including underwater 
explosives and explosives deployed against surface targets) used in the 
mitigation area from November 15 to April 15.
Southeast North Atlantic Right Whale Special Reporting Mitigation Area
    The Action Proponents must report the total annual hours and counts 
of active sonar and in-water explosives (including underwater 
explosives and explosives deployed against surface targets) used within 
the mitigation area from November 15 to April 15. The mitigation area 
extent aligns with the boundaries of the North Atlantic right whale 
critical habitat for reproduction designated by NMFS in 2016 (81 FR 
4838, January 27, 2016).
Rice's Whale Mitigation Area
    The Action Proponents must report the total annual hours and counts 
of active sonar and in-water explosives (including underwater 
explosives and explosives deployed against surface targets) used in the 
mitigation area.
Notification of Injured, Live Stranded, or Dead Marine Mammals
    The Action Proponents would consult the Notification and Reporting 
Plan, which sets out notification, reporting, and other requirements 
when injured, live stranded, or dead marine mammals are detected. The 
Notification and Reporting Plan is available for review at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities.

Annual AFTT Study Area Marine Species Monitoring Report

    The Action Proponents would submit an annual AFTT Study Area marine 
species monitoring report describing the implementation and results 
from the previous calendar year. Data collection methods will be 
standardized across range complexes and the AFTT Study Area to allow 
for comparison in different geographic locations. The draft report must 
be submitted to the Director of the Office of Protected Resources of 
NMFS annually as specified in the LOAs. NMFS will submit comments or 
questions on the report, if any, within 3 months of receipt. The report 
will be considered final after the Action Proponents have addressed 
NMFS' comments, or 3 months after submittal of the draft if NMFS does 
not provide comments on the draft report. The report would describe 
progress of knowledge made with respect to intermediate scientific 
objectives within the AFTT Study Area associated with the ICMP. Similar 
study questions would be treated together so that progress on each 
topic can be summarized across all Navy ranges. The report need not 
include analyses and content that do not provide direct assessment of 
cumulative progress on the monitoring plan study questions.

Annual AFTT Training and Testing Reports

    In the event that the analyzed sound levels were exceeded, the 
Action Proponents would submit a preliminary report(s) detailing the 
exceedance within 21 days after the anniversary date of issuance of the 
LOAs. Regardless of whether analyzed sound levels were exceeded, the 
Navy would submit a detailed report (AFTT Annual Training Exercise 
Report and Testing Activity Report) and Coast Guard would submit a 
detailed report (AFTT Annual Training Exercise Report) to NMFS annually 
as specified in the LOAs. NMFS will submit comments or questions on the 
reports, if any, within 1 month of receipt. The reports will be 
considered final after the Action Proponents have addressed NMFS' 
comments, or 1 month after submittal of the drafts if NMFS does not 
provide comments on the draft reports. The annual report shall contain 
information on MTEs, ship shock trials, SINKEX events, and a summary of 
all sound sources used (total hours or quantity (per the LOA)) of each 
bin of sonar or other non-impulsive source; total annual number of each 
type of explosive exercises; and total annual expended/detonated rounds 
(missiles, bombs, sonobuoys, etc.) for each explosive bin). The annual 
reports will also contain cumulative sonar and explosive use quantity 
from previous years' reports through the current year. Additionally, if 
there were any changes to the sound source allowance in the reporting 
year, or cumulatively, the reports would include a discussion of why 
the change was made and include analysis to support how the change did 
or did not affect the analysis in the 2024 AFTT Draft Supplemental EIS/
OEIS and MMPA final rule. The annual reports would also include the 
details regarding specific requirements associated with specific 
mitigation areas. The analysis in the detailed report would be based on 
the accumulation of data from the current year's report and data 
collected from previous annual reports. The detailed reports shall also 
contain special reporting for the Northeast North Atlantic Right Whale 
Mitigation Area, Gulf of Maine Marine Mammal Mitigation Area, Southeast 
North Atlantic Right Whale Mitigation Area, and Rice's Whale Mitigation 
Area, as described in the LOAs.

Other Reporting and Coordination

    The Action Proponents would continue to report and coordinate with 
NMFS for the following:
    (i) Annual marine species monitoring technical review meetings that 
also include researchers and the Marine Mammal Commission; and
    (ii) Annual Adaptive Management meetings that also include the 
Marine Mammal Commission (and could occur in conjunction with the 
annual marine species monitoring technical review meetings).

Preliminary Analysis and Negligible Impact Determination

General Negligible Impact Analysis

Introduction
    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
taken by Level A harassment or Level B harassment (as presented in 
table 35,

[[Page 20007]]

table 36, and table 37), NMFS considers other factors, such as the 
likely nature of any responses (e.g., intensity, duration) and the 
context of any responses (e.g., critical reproductive time or location, 
migration), as well as effects on habitat and the likely effectiveness 
of the mitigation. We also assess the number, intensity, and context of 
estimated takes by evaluating this information relative to population 
status. Consistent with the 1989 preamble for NMFS' implementing 
regulations (54 FR 40338, September 29, 1989), the impacts from other 
past and ongoing anthropogenic activities are incorporated into this 
analysis via their impacts on the environmental baseline (e.g., as 
reflected in the regulatory status of the species, population size and 
growth rate where known, other ongoing sources of human-caused 
mortality, and ambient noise levels).
    In the Estimated Take of Marine Mammals section, we identified the 
subset of potential effects that would be expected to rise to the level 
of takes both annually and over the 7-year period covered by this 
proposed rule, and then identified the maximum number of takes we 
believe could occur (mortality) or are reasonably expected to occur 
(harassment) based on the methods described. The impact that any given 
take will have is dependent on many case-specific factors that need to 
be considered in the negligible impact analysis (e.g., the context of 
behavioral exposures such as duration or intensity of a disturbance, 
the health of impacted animals, the status of a species that incurs 
fitness-level impacts to individuals, etc.). For this proposed rule we 
evaluated the likely impacts of the enumerated maximum number of 
harassment takes that are proposed for authorization and reasonably 
expected to occur, in the context of the specific circumstances 
surrounding these predicted takes. We also include a specific 
assessment of serious injury or mortality (hereafter referred to as M/
SI) takes that could occur, as well as consideration of the traits and 
statuses of the affected species and stocks. Last, we collectively 
evaluated this information, as well as other more taxa-specific 
information and mitigation measure effectiveness, in group-specific 
assessments that support our negligible impact conclusions for each 
stock or species. Because all of the Action Proponents' specified 
activities would occur within the ranges of the marine mammal stocks 
identified in the rule, all negligible impact analyses and 
determinations are at the stock level (i.e., additional species-level 
determinations are not needed).
Harassment
    The specified activities reflect representative levels of military 
readiness activities. The Description of the Proposed Activity section 
describes annual activities. There may be some flexibility in the exact 
number of hours, items, or detonations that may vary from year to year, 
but take totals would not exceed the maximum annual totals and 7-year 
totals indicated in table 35, table 36, and table 37. We base our 
analysis and negligible impact determination on the maximum number of 
takes that would be reasonably expected to occur annually and are 
proposed to be authorized, although, as stated before, the number of 
takes are only one part of the analysis, which includes extensive 
qualitative consideration of other contextual factors that influence 
the degree of impact of the takes on the affected individuals. To avoid 
repetition, we provide some general analysis immediately below that 
applies to all the species listed in table 35, table 36, and table 37, 
given that some of the anticipated effects of the Action Proponents' 
military readiness activities on marine mammals are expected to be 
relatively similar in nature. Below that, we provide additional 
information specific to Mysticetes, Odontocetes, and Pinnipeds and, 
finally, break our analysis into species (and/or stocks), or groups of 
species (and the associated stocks) where relevant similarities exist, 
to provide more specific information related to the anticipated effects 
on individuals of a specific stock or where there is information about 
the status or structure of any species that would lead to a differing 
assessment of the effects on the species or stock. Organizing our 
analysis by grouping species or stocks that share common traits or that 
will respond similarly to effects of the Action Proponents' activities 
and then providing species- or stock-specific information allows us to 
avoid duplication while assuring that we have analyzed the effects of 
the specified activities on each affected species or stock.
    The Action Proponents' harassment take request is based on one 
model for pile driving, and a second model (NAEMO) for all other 
acoustic stressors, which NMFS reviewed and concurs appropriately 
estimate the maximum amount of harassment that is reasonably likely to 
occur. As described in more detail above, NAEMO calculates sound energy 
propagation from sonar and other transducers, air guns, and explosives 
during military readiness activities; the sound or impulse received by 
animat dosimeters representing marine mammals distributed in the area 
around the modeled activity; and whether the sound or impulse energy 
received by a marine mammal exceeds the thresholds for effects. 
Assumptions in the Navy models intentionally err on the side of 
overestimation when there are unknowns. The effects of the specified 
activities are modeled as though they would occur regardless of 
proximity to marine mammals, meaning that no activity-based mitigation 
is considered (e.g., no power down or shut down). However, the modeling 
does quantitatively consider the possibility that marine mammals would 
avoid continued or repeated sound exposures to some degree, based on a 
species' sensitivity to behavioral disturbance. Additionally, the sonar 
modeling reflects some, but not all, of the geographic mitigation 
measures. NMFS provided input to, independently reviewed, and concurred 
with the Action Proponents on this process and the Action Proponents' 
analysis, which is described in detail in section 6 of the application, 
was used to quantify harassment takes for this rule.
    The Action Proponents and NMFS anticipate more severe effects from 
takes resulting from exposure to higher received levels (though this is 
in no way a strictly linear relationship for behavioral effects 
throughout species, individuals, or circumstances) and less severe 
effects from takes resulting from exposure to lower received levels. 
However, there is also growing evidence of the importance of distance 
in predicting marine mammal behavioral response to sound--i.e., sounds 
of a similar level emanating from a more distant source have been shown 
to be less likely to elicit a response of equal magnitude (DeRuiter 
2012). The estimated number of takes by Level A harassment and Level B 
harassment does not equate to the number of individual animals the 
Action Proponents expect to harass (which is lower), but rather to the 
instances of take (i.e., exposures above the Level A harassment and 
Level B harassment threshold) that are anticipated to occur over the 7-
year period. These instances may represent either brief exposures 
(seconds or minutes) or, in some cases, longer durations of exposure 
within a day. In some cases, an animal that incurs a single take by AUD 
INJ or TTS may also experience a direct behavioral harassment from the 
same exposure. Some individuals may experience multiple instances of 
take (meaning over multiple days) over the course of the

[[Page 20008]]

year, which means that the number of individuals taken is smaller than 
the total estimated takes. Generally speaking, the higher the number of 
takes as compared to the population abundance, the more repeated takes 
of individuals are likely, and the higher the actual percentage of 
individuals in the population that are likely taken at least once in a 
year. We look at this comparative metric (number of takes to population 
abundance) to give us a relative sense of where a larger portion of a 
species is being taken by the specified activities, where there is a 
likelihood that the same individuals are being taken across multiple 
days, and whether the number of days might be higher or more likely 
sequential. Where the number of instances of take is less than 100 
percent of the abundance, and there is no information to specifically 
suggest that some subset of animals is known to congregate in an area 
in which activities are regularly occurring (e.g., a small resident 
population, takes occurring in a known important area such as a BIA, or 
a large portion of the takes occurring in a certain region and season), 
the overall likelihood and number of repeated takes is generally 
considered low, as it could, on one extreme, mean that every take 
represents a separate individual in the population being taken on one 
day (a minimal impact to an individual) or, more likely, that some 
smaller number of individuals are taken on one day annually and some 
are taken on a few, not likely sequential, days annually, and of course 
some are not taken at all.
    In the ocean, the use of sonar and other active acoustic sources is 
often transient and is unlikely to repeatedly expose the same 
individual animals within a short period, for example within one 
specific exercise. However, for some individuals of some species, 
repeated exposures across different activities could occur over the 
year, especially where events occur in generally the same area with 
more resident species. In short, for some species, we expect that the 
total anticipated takes represent exposures of a smaller number of 
individuals of which some would be exposed multiple times, but based on 
the nature of the specified activities and the movement patterns of 
marine mammals, it is unlikely that individuals from most stocks would 
be taken over more than a few days within a given year. This means that 
even where repeated takes of individuals are likely to occur, they are 
more likely to result from non-sequential exposures from different 
activities, and, even if sequential, individual animals are not 
predicted to be taken for more than several days in a row, at most. As 
described elsewhere, the nature of the majority of the exposures would 
be expected to be of a less severe nature, and based on the numbers, it 
is likely that any individual exposed multiple times is still only 
taken on a small percentage of the days of the year. The greater 
likelihood is that not every individual is taken, or perhaps a smaller 
subset is taken with a slightly higher average and larger variability 
of highs and lows, but still with no reason to think that, for most 
species or stocks, any individuals would be taken a significant portion 
of the days of the year.
Physiological Stress Response
    Some of the lower level physiological stress responses (e.g., 
orientation or startle response, change in respiration, change in heart 
rate) discussed earlier would likely co-occur with the predicted 
harassments, although these responses are more difficult to detect and 
fewer data exist relating these responses to specific received levels 
of sound. Level B harassment takes, then, may have a stress-related 
physiological component as well; however, we would not expect the 
Action Proponents' generally short-term, intermittent, and (typically 
in the case of sonar) transitory activities to create conditions of 
long-term continuous noise leading to long-term physiological stress 
responses in marine mammals that could affect reproduction or survival.
Behavioral Response
    The estimates calculated using the BRF do not differentiate between 
the different types of behavioral responses that rise to the level of 
Level B harassment. As described in the application, the Action 
Proponents identified (with NMFS' input) that moderate behavioral 
responses, as characterized in Southall et al. (2021), would be 
considered a take. The behavioral responses predicted by the BRFs are 
assumed to be moderate severity exposures (e.g., altered migration 
paths or dive profiles, interrupted nursing, breeding or feeding, or 
avoidance) that may last for the duration of an exposure. The Action 
Proponents then compiled the available data indicating at what received 
levels and distances those responses have occurred, and used the 
indicated literature to build biphasic behavioral response curves and 
cut-off conditions that are used to predict how many instances of Level 
B behavioral harassment occur in a day (see the ``Criteria and 
Thresholds for U.S. Navy Acoustic and Explosive Effects Analysis (Phase 
4)'' technical report (U.S. Department of the Navy, 2024)). Take 
estimates alone do not provide information regarding the potential 
fitness or other biological consequences of the responses on the 
affected individuals. We therefore consider the available activity-
specific, environmental, and species-specific information to determine 
the likely nature of the modeled behavioral responses and the potential 
fitness consequences for affected individuals.
    Use of sonar and other transducers would typically be transient and 
temporary. The majority of acoustic effects to individual animals from 
sonar and other active sound sources during military readiness 
activities would be primarily from anti-submarine warfare events. It is 
important to note although anti-submarine warfare is one of the warfare 
areas of focus during MTEs, there are significant periods when active 
anti-submarine warfare sonars are not in use. Nevertheless, behavioral 
responses are assumed more likely to be significant during MTEs than 
during other anti-submarine warfare activities due to the duration 
(i.e., multiple days), scale (i.e., multiple sonar platforms), and use 
of high-power hull-mounted sonar in the MTEs. In other words, in the 
range of potential behavioral effects that might be expected as part of 
a response that qualifies as an instance of Level B behavioral 
harassment (which by nature of the way it is modeled/counted, occurs 
within 1 day), the less severe end might include exposure to 
comparatively lower levels of a sound, at a detectably greater distance 
from the animal, for a few or several minutes, and that could result in 
a behavioral response such as avoiding an area that an animal would 
otherwise have chosen to move through or feed in for some amount of 
time or breaking off one or a few feeding bouts. More severe effects 
could occur when the animal gets close enough to the source to receive 
a comparatively higher level, is exposed continuously to one source for 
a longer time, or is exposed intermittently to different sources 
throughout a day. Such effects might result in an animal having a more 
severe flight response and leaving a larger area for a day or more or 
potentially losing feeding opportunities for a day. However, such 
severe behavioral effects are expected to occur infrequently.
    To help assess this, for sonar (LFAS/MFAS/HFAS) used in the AFTT 
Study Area, the Action Proponents provided information estimating the 
instances of take by Level B harassment by behavioral disturbance under 
each BRF

[[Page 20009]]

that would occur within 6-dB increments (discussed below in the Group 
and Species-Specific Analyses section), and by distance in 5-km bins in 
section 2.3.3 of appendix A to the application. As mentioned above, all 
else being equal, an animal's exposure to a higher received level is 
more likely to result in a behavioral response that is more likely to 
lead to adverse effects, which could more likely accumulate to impacts 
on reproductive success or survivorship of the animal, but other 
contextual factors (e.g., distance, duration of exposure, and 
behavioral state of the animals) are also important (Di Clemente et 
al., 2018; Ellison et al., 2012; Moore and Barlow, 2013, Southall et 
al., 2019, Wensveen et al., 2017, etc.). The majority of takes by Level 
B harassment are expected to be in the form of comparatively milder 
responses (i.e., lower-level exposures that still rise to the level of 
take, but would likely be less severe along the continuum of responses 
that qualify as take) of a generally shorter duration. We anticipate 
more severe effects from takes when animals are exposed to higher 
received levels of sound or at closer proximity to the source. Because 
species belonging to taxa that share common characteristics are likely 
to respond and be affected in similar ways, these discussions are 
presented within each species group below in the Group and Species-
Specific Analyses section. As noted previously in this proposed rule, 
behavioral response is likely highly variable between species, 
individuals within a species, and context of the exposure. 
Specifically, given a range of behavioral responses that may be 
classified as Level B harassment, to the degree that higher received 
levels of sound are expected to result in more severe behavioral 
responses, only a smaller percentage of the anticipated Level B 
harassment from the specified activities might result in more severe 
responses (see the Group and Species-Specific Analyses section below 
for more detailed information).
Diel Cycle
    Many animals perform vital functions, such as feeding, resting, 
traveling, and socializing on a diel cycle (24-hour cycle). Behavioral 
responses to noise exposure, when taking place in a biologically 
important context, such as disruption of critical life functions, 
displacement, or avoidance of important habitat, are more likely to be 
significant if they last more than one diel cycle or recur on 
subsequent days (Southall et al., 2007). Henderson et al. (2016) found 
that ongoing smaller scale events had little to no impact on foraging 
dives for Blainville's beaked whale, while multi-day training events 
may decrease foraging behavior for Blainville's beaked whale (Manzano-
Roth et al., 2016). Consequently, a behavioral response lasting less 
than one day and not recurring on subsequent days is not considered 
severe unless it could directly affect reproduction or survival 
(Southall et al., 2007). Note that there is a difference between 
multiple-day substantive behavioral responses and multiple-day 
anthropogenic activities. For example, just because an at-sea exercise 
lasts for multiple days does not necessarily mean that individual 
animals are either exposed to those exercises for multiple days or, 
further, exposed in a manner resulting in a sustained multiple day 
substantive behavioral response. Large multi-day Navy exercises, such 
as anti-submarine warfare activities, typically include vessels moving 
faster than while in transit (typically 10-15 kn (18.5-27.8 km/hr) or 
higher) and generally cover large areas that are relatively far from 
shore (typically more than 3 nmi (5.6 km) from shore) and in waters 
greater than 600 ft (182.9 m) deep. Marine mammals are moving as well, 
which would make it unlikely that the same animal could remain in the 
immediate vicinity of the ship for the entire duration of the exercise. 
Further, the Action Proponents do not necessarily operate active sonar 
the entire time during an exercise. While it is certainly possible that 
these sorts of exercises could overlap with individual marine mammals 
multiple days in a row at levels above those anticipated to result in a 
take, because of the factors mentioned above, it is considered unlikely 
for the majority of takes. However, it is also worth noting that the 
Action Proponents conduct many different types of noise-producing 
activities over the course of the year and it is likely that some 
marine mammals will be exposed to more than one activity and taken on 
multiple days, even if they are not sequential.
    Durations of Navy activities utilizing tactical sonar sources and 
explosives vary and are fully described in chapter 2 of the 2024 AFTT 
Draft Supplemental EIS/OEIS. Sonar used during anti-submarine warfare 
would impart the greatest amount of acoustic energy of any category of 
sonar and other transducers analyzed in the application and include 
hull-mounted, towed, line array, sonobuoy, helicopter dipping, and 
torpedo sonars. Most anti-submarine warfare sonars are MFAS (1-10 kHz); 
however, some sources may use higher or lower frequencies. Anti-
submarine warfare training activities using hull-mounted sonar proposed 
for the AFTT Study Area generally last for only a few hours. However, 
anti-submarine warfare testing activities range from several hours, to 
days, to more than 10 days for large integrated anti-submarine warfare 
MTEs (see table 4 and table 5). For these multi-day exercises there 
will typically be extended intervals of non-activity in between active 
sonar periods. Because of the need to train in a large variety of 
situations, the Navy conducts anti-submarine warfare training exercises 
in varying locations. Given the average length and dynamic nature of 
anti-submarine warfare exercises (times of sonar use) and typical 
vessel speed, combined with the fact that the majority of the cetaceans 
would not likely remain in proximity to the sound source, it is 
unlikely that an animal would be exposed to LFAS/MFAS/HFAS at levels or 
durations likely to result in a substantive response that would then be 
carried on for more than one day or on successive days.
    Most planned explosive events are instantaneous or scheduled to 
occur over a short duration (less than 2 hours) and the explosive 
component of these activities only lasts for minutes. Although 
explosive exercises may sometimes be conducted in the same general 
areas repeatedly, because of their short duration and the fact that 
they are in the open ocean and animals can easily move away, it is 
similarly unlikely that animals would be exposed for long, continuous 
amounts of time, or demonstrate sustained behavioral responses. 
Although SINKEXs may last for up to 48 hours (4-8 hours typically, 
possibly 1-2 days), they are almost always completed in a single day 
and only one event is planned annually for the AFTT Study Area (see 
table 6). They are stationary and conducted in deep, open water (where 
fewer marine mammals would typically be expected to be randomly 
encountered), and they have rigorous monitoring (see table 64) and 
shutdown procedures all of which make it unlikely that individuals 
would be exposed to the exercise for extended periods or on consecutive 
days, though some individuals may be exposed on multiple days.
Assessing the Number of Individuals Taken and the Likelihood of 
Repeated Takes
    As described previously, Navy modeling uses the best available 
science to predict the instances of exposure above certain acoustic 
thresholds, which are equated, as appropriate, to harassment takes. As 
further noted, for

[[Page 20010]]

active acoustics it is more challenging to parse out the number of 
individuals taken by Level B harassment and the number of times those 
individuals are taken from this larger number of instances, though 
factors such as movement ecology (e.g., is the species resident and 
more likely to remain in closer proximity to ongoing activities, versus 
nomadic or migratory; Keen et al. 2021) or whether there are known BIAs 
where animals are known to congregate can help inform this. One method 
that NMFS uses to help better understand the overall scope of the 
impacts is to compare these total instances of take against the 
abundance of that species (or stock if applicable). For example, if 
there are 100 harassment takes in a population of 100, one can assume 
either that every individual was exposed above acoustic thresholds once 
per year, or that some smaller number were exposed a few times per 
year, and a few were not exposed at all. Where the instances of take 
exceed 100 percent of the population, multiple takes of some 
individuals are predicted and expected to occur within a year. 
Generally speaking, the higher the number of takes as compared to the 
population abundance, the more multiple takes of individuals are 
likely, and the higher the actual percentage of individuals in the 
population that are likely taken at least once in a year. We look at 
this comparative metric to give us a relative sense of where larger 
portions of the species are being taken by the Action Proponents' 
activities and where there is a higher likelihood that the same 
individuals are being taken across multiple days and where that number 
of days might be higher. It also provides a relative picture of the 
scale of impacts to each species.
    In the ocean, unlike a modeling simulation with static animals, the 
transient nature of sonar use makes it unlikely to repeatedly expose 
the same individual animals within a short period, for example, within 
one specific exercise. However, some repeated exposures across 
different activities could occur over the year with more resident 
species. In short, we expect the total anticipated takes represent 
exposures of a smaller number of individuals of which some could be 
exposed multiple times, but based on the nature of the Action 
Proponents' activities and the movement patterns of marine mammals, it 
is unlikely that any particular subset would be taken over more than 
several sequential days (with a few possible exceptions discussed in 
the species-specific conclusions). In other cases, such as during 
pierside sonar testing at Naval Station Norfolk, repeated exposures of 
the same individuals may be more likely given the concentrated area 
within which the operations occur and the likelihood that a smaller 
number of animals would routinely use the affected habitat.
    When calculating the proportion of a population taken (e.g., the 
number of takes divided by population abundance), which can also be 
helpful in estimating the number of days over which some individuals 
may be taken, it is important to choose an appropriate population 
estimate against which to make the comparison. Herein, NMFS considers 
two potential abundance estimates, the SARs and the NMSDD abundance 
estimates. The SARs, where available, provide the official population 
estimate for a given species or stock in U.S. waters in a given year. 
These estimates are typically generated from the most recent shipboard 
and/or aerial surveys conducted, and in some cases, the estimates show 
substantial year-to-year variability. When the stock is known to range 
well outside of U.S. EEZ boundaries, population estimates based on 
surveys conducted only within the U.S. EEZ are known to be 
underestimates. The NMSDD-derived abundance estimates are abundances 
for within the U.S. EEZ boundaries only and, therefore, differ from 
some SAR abundance estimates.
    The SAR and NMSDD abundance estimates can differ substantially 
because these estimates may be based on different methods and data 
sources. For example, the SARs only consider data from the past 8 year 
period, whereas the NMSDD considers a longer data history. Further, the 
SARs estimate the number of animals in a population but not spatial 
densities. NMSDD uses predictive density models to estimate species 
presence, even where sighting data is limited or lacking altogether. 
Thus, NMSDD density models beyond the U.S. EEZ have greater uncertainty 
than those within the U.S. EEZ, where most proposed activities would 
occur. Each density model is limited to the variables and assumptions 
considered by the original data source provider. NMFS considered these 
factors and others described in the Density Technical Report (U.S. 
Department of the Navy, 2024) when comparing the estimated takes to 
current population abundances for each species or stock.
    In consideration of the factors described above, to estimate 
repeated impacts across large areas relative to species geographic 
distributions, comparing the impacts predicted in NAEMO to abundances 
predicted using the NMSDD models is usually preferable. By comparing 
estimated take to the NMSDD abundance estimates, impacts and abundance 
estimates are based on the same underlying assumptions about a species' 
presence. NMFS has compared the estimated take to the NMSDD abundance 
estimates herein for all stocks, with the exception of stocks where the 
abundance information fits into one of the following scenarios, in 
which case NMFS concluded that comparison to the SAR abundance estimate 
is more appropriate: (1) a species' or stocks' range extends beyond the 
U.S. EEZ and the SAR abundance estimate is greater than the NMSDD 
abundance. For highly migratory species (e.g., large whales) or those 
whose geographic distribution extends beyond the boundaries of the AFTT 
Study Area (e.g., populations with distribution along the entire 
western Atlantic Ocean rather than just the AFTT Study Area), 
comparisons to the SAR are appropriate. Many of the stocks present in 
the AFTT Study Area have ranges significantly larger than the AFTT 
Study Area, and that abundance is captured by the SAR. A good 
descriptive example is migrating large whales, which occur seasonally 
in the AFTT Study Area. Therefore, at any one time there may be a 
stable number of animals, but over the course of the entire year the 
entire population may pass through the AFTT Study Area. Therefore, 
comparing the estimated takes to an abundance, in this case the SAR 
abundance, which represents the total population, may be more 
appropriate than modeled abundances for only the AFTT Study Area; and 
(2) when the current minimum population estimate in the SAR is greater 
than the NMSDD abundance, regardless of whether the stock range extends 
beyond the EEZ. The NMSDD and SAR abundance estimates are both included 
in table 81 (mysticetes), table 83 (sperm whales, dwarf sperm whales, 
and pygmy sperm whales), table 85 (beaked whales), table 87 (dolphins 
and small whales), table 89 (porpoises), and table 91 (pinnipeds), and 
each table indicates which stock abundance estimate was selected for 
comparison to the take estimate for each species or stock.
Temporary Threshold Shift
    NMFS and the Navy have estimated that all species of marine mammals 
may incur some level of TTS from active sonar. As mentioned previously, 
in general, TTS can last from a few minutes to days, be of varying 
degree, and occur across various frequency bandwidths, all of which 
determine the severity of the impacts on the affected individual, which 
can range from minor

[[Page 20011]]

to more severe. Table 38 through table 46 indicate the number of takes 
by TTS that may be incurred by different species from exposure to 
active sonar, air guns, pile driving, and explosives. The TTS incurred 
by an animal is primarily characterized by three characteristics:
    (i) Frequency--Available data suggest that most TTS occurs in the 
frequency range of the source up to one octave higher than the source 
(with the maximum TTS at \1/2\ octave above) (Finneran 2015, Southall 
et al. 2019). The Navy's MF anti-submarine warfare sources, which are 
the highest power and most numerous sources and the ones that cause the 
most take by TTS, utilize the 1-10 kHz frequency band, which suggests 
that if TTS were to be induced by any of these MF sources it would be 
in a frequency band somewhere between approximately 1 and 20 kHz, which 
is in the range of communication calls for many odontocetes, but below 
the range of the echolocation signals used for foraging. There are 
fewer hours of HF source use and the sounds would attenuate more 
quickly, plus they have lower source levels, but if an animal were to 
incur TTS from these sources, it would cover a higher frequency range 
(sources are between 10 and 100 kHz, which means that TTS could range 
up to the highest frequencies audible to VHF cetaceans, approaching 200 
kHz), which could overlap with the range in which some odontocetes 
communicate or echolocate. However, HF systems are typically used less 
frequently and for shorter time periods than surface ship and aircraft 
MF systems, so TTS from HF sources is less likely than from MF sources. 
There are fewer LF sources and the majority are used in the more 
readily mitigated testing environment, and TTS from LF sources would 
most likely occur below 2 kHz, which is in the range where many 
mysticetes communicate and also where other auditory cues are located 
(waves, snapping shrimp, fish prey). Also of note, the majority of 
sonar sources from which TTS may be incurred occupy a narrow frequency 
band, which means that the TTS incurred would also be across a narrower 
band (i.e., not affecting the majority of an animal's hearing range).
    (ii) Degree of the shift (i.e., by how many dB the sensitivity of 
the hearing is reduced)--Generally, both the degree of TTS and the 
duration of TTS will be greater if the marine mammal is exposed to a 
higher level of energy (which would occur when the peak SPL is higher 
or the duration is longer). The threshold for the onset of TTS was 
discussed previously in this rule. An animal would have to approach 
closer to the source or remain in the vicinity of the sound source 
appreciably longer to increase the received SEL, which would be 
difficult considering the Lookouts and the nominal speed of an active 
sonar vessel (10-15 kn (18.5-27.8 km/hr)) and the relative motion 
between the sonar vessel and the animal. In the TTS studies discussed 
in the Potential Effects of Specified Activities on Marine Mammals and 
Their Habitat section, some using exposures of almost an hour in 
duration or up to 217 SEL, most of the TTS induced was 15 dB or less, 
though Finneran et al. (2007) induced 43 dB of TTS with a 64-second 
exposure to a 20 kHz source. The SQS-53 (MFAS) hull-mounted sonar (MF1) 
nominally emits a short (1-second) ping typically every 50 seconds, 
incurring those levels of TTS due to this source is highly unlikely. 
Sources with higher duty cycles produce longer ranges to effects and 
contribute to auditory effects from this action. Since any hull-mounted 
sonar, such as the SQS-53, engaged in anti-submarine warfare training 
would be moving at between 10 and 15 kn (18.5 to 27.8 km/hr) and 
nominally pinging every 50 seconds, the vessel will have traveled a 
minimum distance of approximately 843.2 ft (257 m) during the time 
between those pings. For a Navy vessel moving at a nominal 10 kn (18.5 
km/hr), it is unlikely a marine mammal would track with the ship and 
could maintain speed parallel to the ship to receive adequate energy 
over successive pings to suffer TTS. In short, given the anticipated 
duration and levels of sound exposure, we would not expect marine 
mammals to incur more than relatively low levels of TTS in most cases 
for sonar exposure. To add context to this degree of TTS, individual 
marine mammals may regularly experience variations of 6 dB differences 
in hearing sensitivity in their lifetime (Finneran et al., 2000, 
Finneran et al., 2002, Schlundt et al., 2000).
    (iii) Duration of TTS (recovery time)--In the TTS laboratory 
studies (as discussed in the Potential Effects of Specified Activities 
on Marine Mammals and Their Habitat section), some using exposures of 
almost an hour in duration or up to 217 dB SEL, almost all individuals 
recovered within 1 day (or less, often in minutes), although in one 
study (Finneran et al., 2015; Southall et al. 2019), recovery took 4 
days.
    Compared to laboratory studies, marine mammals are likely to 
experience lower SELs from sonar used in the AFTT Study Area due to 
movement of the source and animals, and because of the lower duty 
cycles typical of higher power sources (though some of the Navy MF1C 
sources have higher duty cycles). Therefore, TTS resulting from MFAS 
would likely be of lesser magnitude and duration compared to laboratory 
studies. Also, for the same reasons discussed in the Preliminary 
Analysis and Negligible Impact Determination--Diel Cycle section, and 
because of the short distance between the source and animals needed to 
reach high SELs, it is unlikely that animals would be exposed to the 
levels necessary to induce TTS in subsequent time periods such that 
hearing recovery is impeded. Additionally, though the frequency range 
of TTS that marine mammals might incur would overlap with some of the 
frequency ranges of their vocalization types, the frequency range of 
TTS from MFAS would not usually span the entire frequency range of one 
vocalization type, much less span all types of vocalizations or other 
critical auditory cues.
    As a general point, the majority of the TTS takes are the result of 
exposure to hull-mounted MFAS (MF narrower band sources), with fewer 
from explosives (broad-band lower frequency sources), and even fewer 
from LFAS or HFAS sources (narrower band). As described above, we 
expect the majority of these takes to be in the form of mild, short-
term (minutes to hours), narrower band (only affecting a portion of the 
animal's hearing range) TTS. This means that for one to several times 
per year, for several minutes, maybe a few hours, or at most in limited 
circumstances a few days, a taken individual will have diminished 
hearing sensitivity (more than natural variation, but nowhere near 
total deafness). More often than not, such an exposure would occur 
within a narrower mid- to higher frequency band that may overlap part 
(but not all) of a communication, echolocation, or predator range, but 
sometimes across a lower or broader bandwidth. The significance of TTS 
is also related to the auditory cues that are germane within the time 
period that the animal incurs the TTS. For example, if an odontocete 
has TTS at echolocation frequencies, but incurs it at night when it is 
resting and not feeding, it is not impactful. In short, the expected 
results of any one of these small number of mild TTS occurrences could 
be that (1) it does not overlap signals that are pertinent to that 
animal in the given time period, (2) it overlaps parts of signals that 
are important to the animal, but not in a manner that impairs 
interpretation, or (3) it reduces

[[Page 20012]]

detectability of an important signal to a small degree for a short 
amount of time--in which case the animal may be aware and be able to 
compensate (but there may be slight energetic cost), or the animal may 
have some reduced opportunities (e.g., to detect prey) or reduced 
capabilities to react with maximum effectiveness (e.g., to detect a 
predator or navigate optimally). However, it is unlikely that 
individuals would experience repeated or high degree TTS overlapping in 
frequency and time with signals critical for behaviors that would 
impact overall fitness.
Auditory Masking or Communication Impairment
    The ultimate potential impacts of masking on an individual (if it 
were to occur) are similar to those discussed for TTS, but an important 
difference is that masking only occurs during the time of the signal, 
versus TTS, which continues beyond the duration of the signal. 
Fundamentally, masking is referred to as a chronic effect because one 
of the key harmful components of masking is its duration--the fact that 
an animal would have reduced ability to hear or interpret critical cues 
becomes much more likely to cause a problem the longer it is occurring. 
Also inherent in the concept of masking is the fact that the potential 
for the effect is only present during the times that the animal and the 
source are in close enough proximity for the effect to occur (and 
further, this time period would need to coincide with a time that the 
animal was utilizing sounds at the masked frequency). As our analysis 
has indicated, because of the relative movement of vessels and the 
sound sources primarily involved in this rule, we do not expect the 
exposures with the potential for masking to be of a long duration.
    Masking is fundamentally more of a concern at lower frequencies, 
because low frequency signals propagate significantly farther than 
higher frequencies and because they are more likely to overlap both the 
narrower LF calls of mysticetes, as well as many non-communication cues 
such as fish and invertebrate prey, and geologic sounds that inform 
navigation. Masking is also more of a concern from continuous sources 
(versus intermittent sonar signals) where there is no quiet time 
between pulses and detection and interpretation of auditory signals is 
likely more challenging. For these reasons, dense aggregations of, and 
long exposure to, continuous LF activity are much more of a concern for 
masking, whereas comparatively short-term exposure to the predominantly 
intermittent pulses of often narrow frequency range MFAS or HFAS, or 
explosions are not expected to result in a meaningful amount of 
masking. While the Action Proponents occasionally use LF and more 
continuous sources, it is not in the contemporaneous aggregate amounts 
that would be expected to accrue to degrees that would have the 
potential to affect reproductive success or survival. Additional detail 
is provided below.
    Standard hull-mounted MFAS typically pings every 50 seconds. Some 
hull-mounted anti-submarine sonars can also be used in an object 
detection mode known as ``Kingfisher'' mode (e.g., used on vessels when 
transiting to and from port) where pulse length is shorter but pings 
are much closer together in both time and space since the vessel goes 
slower when operating in this mode, and during which an increased 
likelihood of masking in the vicinity of vessel could be expected. For 
the majority of other sources, however, the pulse length is 
significantly shorter than hull-mounted active sonar, on the order of 
several microseconds to tens of milliseconds. Some of the vocalizations 
that many marine mammals make are less than 1 second long, so, for 
example with hull-mounted sonar, there would be a 1 in 50 chance (only 
if the source was in close enough proximity for the sound to exceed the 
signal that is being detected) that a single vocalization might be 
masked by a ping. However, when vocalizations (or series of 
vocalizations) are longer than the 1 second pulse of hull-mounted 
sonar, or when the pulses are only several microseconds long, the 
majority of most animals' vocalizations would not be masked.
    Most anti-submarine warfare sonars and countermeasures use MF 
frequencies and a few use LF and HF frequencies. Most of these sonar 
signals are limited in the temporal, frequency, and spatial domains. 
The duration of most individual sounds is short, lasting up to a few 
seconds each. A few systems operate with higher duty cycles or nearly 
continuously, but they typically use lower power, which means that an 
animal would have to be closer, or in the vicinity for a longer time, 
to be masked to the same degree as by a higher level source. 
Nevertheless, masking could occasionally occur at closer ranges to 
these high-duty cycle and continuous active sonar systems, but as 
described previously, it would be expected to be of a short duration. 
While data are lacking on behavioral responses of marine mammals to 
continuously active sonars, mysticete species are known to habituate to 
novel and continuous sounds (Nowacek et al., 2004), suggesting that 
they are likely to have similar responses to high-duty cycle sonars. 
Furthermore, most of these systems are hull-mounted on surface ships 
with the ships moving at least 10 kn (18.5 km/hr), and it is unlikely 
that the ship and the marine mammal would continue to move in the same 
direction and the marine mammal subjected to the same exposure due to 
that movement. Most anti-submarine warfare activities are 
geographically dispersed and last for only a few hours, often with 
intermittent sonar use even within this period. Most anti-submarine 
warfare sonars also have a narrow frequency band (typically less than 
one-third octave). These factors reduce the likelihood of sources 
causing significant masking. HF signals (above 10 kHz) attenuate more 
rapidly in the water due to absorption than do lower frequency signals, 
thus producing only a very small zone of potential masking. If masking 
or communication impairment were to occur briefly, it would more likely 
be in the frequency range of MFAS (the more powerful source), which 
overlaps with some odontocete vocalizations (but few mysticete 
vocalizations); however, it would likely not mask the entirety of any 
particular vocalization, communication series, or other critical 
auditory cue, because the signal length, frequency, and duty cycle of 
the MFAS/HFAS signal does not perfectly resemble the characteristics of 
any single marine mammal species' vocalizations.
    Other sources used in the Action Proponents' training and testing 
that are not explicitly addressed above, many of either higher 
frequencies (meaning that the sounds generated attenuate even closer to 
the source) or used less frequently, would be expected to contribute to 
masking over far smaller areas and/or times. For the reasons described 
here, any limited masking that could potentially occur would be minor 
and short-term.
    In conclusion, masking is more likely to occur in the presence of 
broadband, relatively continuous noise sources such as from vessels, 
however, the duration of temporal and spatial overlap with any 
individual animal and the spatially separated sources that the Action 
Proponents use would not be expected to result in more than short-term, 
low impact masking that would not affect reproduction or survival.

[[Page 20013]]

Auditory Injury From Sonar Acoustic Sources and Explosives and Non-
Auditory Injury From Explosives
    Table 38 through table 46 indicate the number of takes of each 
species by Level A harassment in the form of auditory injury resulting 
from exposure to active sonar and/or explosives is estimated to occur, 
and table 50 indicates the totals across all activities. The number of 
takes estimated to result from auditory injury annually from sonar, air 
guns, and explosives for each species/stock from all activities 
combined ranges from 0 to 180 (the 180 is for the Western North 
Atlantic stock of dwarf sperm whale). Nineteen stocks (all odontocetes) 
have the potential to incur non-auditory injury from explosives, and 
the number of individuals from any given stock from all activities 
combined ranges from 1 to 3 (the 3 is for the Northern Gulf of America 
stock of pantropical spotted dolphin). As described previously, the 
Navy's model likely overestimates the number of injurious takes to some 
degree. Nonetheless, these Level A harassment take numbers represent 
the maximum number of instances in which marine mammals would be 
reasonably expected to incur auditory and/or non-auditory injury, and 
we have analyzed them accordingly.
    If a marine mammal is able to approach a surface vessel within the 
distance necessary to incur auditory injury in spite of the mitigation 
measures, the likely speed of the vessel (nominally 10-15 kn (18.5-27.8 
km/hr)) and relative motion of the vessel would make it very difficult 
for the animal to remain in range long enough to accumulate enough 
energy to result in more than a mild case of auditory injury. As 
discussed previously in relation to TTS, the likely consequences to the 
health of an individual that incurs auditory injury can range from mild 
to more serious, and is dependent upon the degree of auditory injury 
and the frequency band associated with auditory injury. The majority of 
any auditory injury incurred as a result of exposure to Navy sources 
would be expected to be in the 2-20 kHz range (resulting from the most 
powerful hull-mounted sonar) and could overlap a small portion of the 
communication frequency range of many odontocetes, whereas other marine 
mammal groups have communication calls at lower frequencies. Because of 
the broadband nature of explosives, auditory injury incurred from 
exposure to explosives would occur over a lower, but wider, frequency 
range. Regardless of the frequency band, the more important point in 
this case is that any auditory injury accrued as a result of exposure 
to Navy activities would be expected to be of a small amount (single 
digits). Permanent loss of some degree of hearing is a normal 
occurrence for older animals, and many animals are able to compensate 
for the shift, both in old age or at younger ages as the result of 
stressor exposure. While a small loss of hearing sensitivity may 
include some degree of energetic costs for compensating or may mean 
some small loss of opportunities or detection capabilities, at the 
expected scale it would be unlikely to impact behaviors, opportunities, 
or detection capabilities to a degree that would interfere with 
reproductive success or survival.
    The Action Proponents implement mitigation measures (described in 
the Proposed Mitigation Measures section) during explosive activities, 
including delaying detonations when a marine mammal is observed in the 
mitigation zone. Nearly all explosive events would occur during 
daylight hours thereby improving the sightability of marine mammals and 
mitigation effectiveness. Observing for marine mammals during the 
explosive activities would include visual and passive acoustic 
detection methods (the latter when they are available and part of the 
activity) before the activity begins, in order to cover the mitigation 
zones that can range from 200 yd (183 m) to 2,500 yd (2,286 m) 
depending on the source (e.g., explosive sonobuoy, explosive torpedo, 
explosive bombs), and 2.5 nmi (4.6 km) for sinking exercises (see table 
55 through table 64).
    The type and amount of take by Level A harassment are indicated for 
all species and species groups in table 81, table 83, table 85, table 
87, table 89, and table 91. Generally speaking, non-auditory injuries 
from explosives could range from minor lung injuries (the most 
sensitive organ and first to be affected) that consist of some short-
term reduction of health and fitness immediately following the injury 
that heals quickly and will not have any discernible long-term effects, 
up to more impactful permanent injuries across multiple organs that may 
cause health problems and negatively impact reproductive success (i.e., 
increase the time between pregnancies or even render reproduction 
unlikely) but fall just short of a ``serious injury'' by virtue of the 
fact that the animal is not expected to die. Nonetheless, due to the 
Navy's mitigation and detection capabilities, we would not expect 
marine mammals to typically be exposed to a more severe blast located 
closer to the source--so the impacts likely would be less severe. In 
addition, most non-auditory injuries and mortalities or serious 
injuries are predicted for stocks with medium to large group sizes, 
mostly delphinids, which increases sightability. It is still difficult 
to evaluate how these injuries may or may not impact an animal's 
fitness, however, these effects are only seen in very small numbers 
(single digits for all stocks) and mostly in species of moderate, high, 
and very high abundances. In short, it is unlikely that any, much less 
all, of the small number of injuries accrued to any one stock would 
result in reduced reproductive success of any individuals; even if a 
few injuries did result in reduced reproductive success of individuals, 
the status of the affected stocks are such that it would not be 
expected to adversely impact rates of reproduction (and auditory injury 
of the low severity anticipated here is not expected to affect the 
survival of any individual marine mammals).
Serious Injury and Mortality
    NMFS is authorizing a very small number of serious injuries or 
mortalities that could occur in the event of a vessel strike or as a 
result of marine mammal exposure to explosive detonations (mostly 
during ship shock trials). We note here that the takes from potential 
vessel strikes or explosive exposures enumerated below could result in 
non-serious injury, but their worst potential outcome (mortality) is 
analyzed for the purposes of the negligible impact determination.
    The MMPA requires that PBR be estimated in SARs and that it be used 
in applications related to the management of take incidental to 
commercial fisheries (i.e., the take reduction planning process 
described in section 118 of the MMPA and the determination of whether a 
stock is ``strategic'' as defined in section 3). While nothing in the 
statute requires the application of PBR outside the management of 
commercial fisheries interactions with marine mammals, NMFS recognizes 
that as a quantitative metric, PBR may be useful as a consideration 
when evaluating the impacts of other human-caused activities on marine 
mammal stocks. Outside the commercial fishing context, and in 
consideration of all known human-caused mortality, PBR can help inform 
the potential effects of M/SI requested to be authorized under section 
101(a)(5)(A). As noted by NMFS and the U.S. FWS in our implementing 
regulations for the 1986 amendments to the MMPA (54 FR 40341, September 
29, 1989), the Services consider many factors, when available, in 
making a negligible impact determination,

[[Page 20014]]

including, but not limited to, the status of the species or stock 
relative to OSP (if known); whether the recruitment rate for the 
species or stock is increasing, decreasing, stable, or unknown; the 
size and distribution of the population; and existing impacts and 
environmental conditions. In this multi-factor analysis, PBR can be a 
useful indicator for when, and to what extent, the agency should take 
an especially close look at the circumstances associated with the 
potential mortality, along with any other factors that could influence 
annual rates of recruitment or survival.
    Below we describe how PBR is considered in NMFS M/SI analysis. 
Please see the 2020 Northwest Training and Testing Final Rule (85 FR 
72312, November 12, 2020) for a background discussion of PBR and how it 
was adopted for use authorizing incidental take under section 
101(a)(5)(A) for specified activities such as the Action Proponent's 
training and testing in the AFTT Study Area.
    When considering PBR during evaluation of effects of M/SI under 
section 101(a)(5)(A), we utilize a two-tiered analysis for each stock 
for which M/SI is proposed for authorization:
    (i) Tier 1: Compare the total human-caused average annual M/SI 
estimate from all sources, including the M/SI proposed for 
authorization from the specific activity, to PBR. If the total M/SI 
estimate is less than or equal to PBR, then the specific activity is 
considered to have a negligible impact on that stock. If the total M/SI 
estimate (including from the specific activity) exceeds PBR, conduct 
the Tier 2 analysis.
    (ii) Tier 2: Evaluate the estimated M/SI from the specified 
activity relative to the stock's PBR. If the M/SI from the specified 
activity is less than or equal to 10 percent of PBR and other major 
sources of human-caused mortality have mitigation in place, then the 
individual specified activity is considered to have a negligible impact 
on that stock. If the estimate exceeds 10 percent of PBR, then, absent 
other mitigating factors, the specified activity is considered likely 
to have a non-negligible impact on that stock.
    Additional detail regarding the two tiers of the evaluation are 
provided below.
    As indicated above, the goal of the Tier 1 assessment is to 
determine whether total annual human-caused mortality, including from 
the specified activity, would exceed PBR. To aid in the Tier 1 
evaluation and get a clearer picture of the amount of annual M/SI that 
remains without exceeding PBR, for each species or stock, we first 
calculate a ``residual PBR,'' which equals PBR minus the ongoing annual 
human-caused M/SI (i.e., Residual PBR = PBR - (annual M/SI estimate 
from the SAR + other M/SI authorized under 101(a)(5)(A)). If the 
ongoing human-caused M/SI from other sources does not exceed PBR, then 
residual PBR is a positive number, and we consider how the proposed 
authorized incidental M/SI from the specified activities being 
evaluated compares to residual PBR using the Tier 1 framework in the 
following paragraph. If the ongoing anthropogenic mortality from other 
sources already exceeds PBR, then residual PBR is a negative number and 
we move to the Tier 2 discussion further below to consider the M/SI 
from the specific activities.
    To reiterate the Tier 1 analysis overview in the context of 
residual PBR, if the M/SI from the specified activity does not exceed 
PBR, the impacts of the authorized M/SI on the species or stock are 
generally considered to be negligible. As a simplifying analytical tool 
in the Tier 1 evaluation, we first consider whether the M/SI from the 
specified activities could cause incidental M/SI that is less than 10 
percent of residual PBR, which we consider an ``insignificance 
threshold.'' If so, we consider M/SI from the specified activities to 
represent an insignificant incremental increase in ongoing 
anthropogenic M/SI for the marine mammal stock in question that alone 
will clearly not adversely affect annual rates of recruitment and 
survival and for which additional analysis or discussion of the 
anticipated M/SI is not required because the negligible impact standard 
clearly will not be exceeded on that basis alone.
    When the M/SI from the specified activity is above the 
insignificance threshold in the Tier 1 evaluation, it does not indicate 
that the M/SI associated with the specified activities is necessarily 
approaching a level that would exceed negligible impact. Rather, it is 
used a cue to look more closely if and when the M/SI for the specified 
activity approaches residual PBR, as it becomes increasingly necessary 
(the closer the M/SI from the specified activity is to 100 percent 
residual PBR) to carefully consider whether there are other factors 
that could affect reproduction or survival, such as take by Level A 
and/or Level B harassment that has been predicted to impact 
reproduction or survival of individuals, or other considerations such 
as information that illustrates high uncertainty involved in the 
calculation of PBR for some stocks. Recognizing that the impacts of 
harassment of any authorized incidental take (by Level A or Level B 
harassment from the specified activities) would not combine with the 
effects of the authorized M/SI to adversely affect the stock through 
effects on recruitment or survival, if the proposed authorized M/SI for 
the specified activity is less than residual PBR, the M/SI, alone, 
would be considered to have a negligible impact on the species or 
stock. If the proposed authorized M/SI is greater than residual PBR, 
then the assessment should proceed to Tier 2.
    For the Tier 2 evaluation, recognizing that the total annual human-
caused M/SI exceeds PBR, we consider whether the incremental effects of 
the proposed authorized M/SI for the specified activity, specifically, 
would be expected to result in a negligible impact on the affected 
species or stocks. For the Tier 2 assessment, consideration of other 
factors (positive or negative), including those described above (e.g., 
the certainty in the data underlying PBR and the impacts of any 
harassment authorized for the specified activity), as well as the 
mitigation in place to reduce M/SI from other activities is especially 
important to assessing the impacts of the M/SI from the specified 
activity on the species or stock. PBR is a conservative metric and not 
sufficiently precise to serve as an absolute predictor of population 
effects upon which mortality caps would appropriately be based. For 
example, in some cases stock abundance (which is one of three key 
inputs into the PBR calculation) is underestimated because marine 
mammal survey data within the U.S. EEZ are used to calculate the 
abundance even when the stock range extends well beyond the U.S. EEZ. 
An underestimate of abundance could result in an underestimate of PBR. 
Alternatively, we sometimes may not have complete M/SI data beyond the 
U.S. EEZ to compare to PBR, which could result in an overestimate of 
residual PBR. The accuracy and certainty around the data that feed any 
PBR calculation, such as the abundance estimates, must be carefully 
considered to evaluate whether the calculated PBR accurately reflects 
the circumstances of the particular stock.
    Also, as referenced above, in some cases the ongoing human-caused 
mortality from activities other than those being evaluated already 
exceeds PBR and, therefore, residual PBR is negative. In these cases, 
any additional mortality, no matter how small, and no matter how small 
relative to the mortality caused by other human activities, would 
result in greater exceedance of PBR. PBR is helpful in

[[Page 20015]]

informing the analysis of the effects of mortality on a species or 
stock because it is important from a biological perspective to be able 
to consider how the total mortality in a given year may affect the 
population. However, section 101(a)(5)(A) of the MMPA indicates that 
NMFS shall authorize the requested incidental take from a specified 
activity if we find that ``the total of such taking [i.e., from the 
specified activity] will have a negligible impact on such species or 
stock.'' In other words, the task under the statute is to evaluate the 
applicant's anticipated take in relation to their take's impact on the 
species or stock, not other entities' impacts on the species or stock. 
Neither the MMPA nor NMFS' implementing regulations call for 
consideration of other unrelated activities and their impacts on the 
species or stock.
    Accordingly, we may find that the impacts of the taking from the 
specified activity may (alone) be negligible even when total human-
caused mortality from all activities exceeds PBR if (in the context of 
a particular species or stock). Specifically, where the authorized M/SI 
would be less than or equal to 10 percent of PBR and management 
measures are being taken to address M/SI from the other contributing 
activities (i.e., other than the specified activities covered by the 
incidental take authorization under consideration), the impacts of the 
authorized M/SI would be considered negligible. In addition, we must 
also still determine that any impacts on the species or stock from 
other types of take (i.e., harassment) caused by the applicant do not 
combine with the impacts from mortality or serious injury addressed 
here to result in adverse effects on the species or stock through 
effects on annual rates of recruitment or survival.
    As noted above, while PBR is useful in informing the evaluation of 
the effects of M/SI in section 101(a)(5)(A) determinations, it is one 
consideration to be assessed in combination with other factors and is 
not determinative. For example, as explained above, the accuracy and 
certainty of the data used to calculate PBR for the species or stock 
must be considered. And we reiterate the considerations discussed above 
for why it is not appropriate to consider PBR an absolute cap in the 
application of this guidance. Accordingly, we use PBR as a trigger for 
concern while also considering other relevant factors to provide a 
reasonable and appropriate means of evaluating the effects of potential 
mortality on rates of recruitment and survival, while acknowledging 
that it is possible for total human-caused M/SI to exceed PBR (or for 
the M/SI from the specified activity to exceed 10 percent of PBR in the 
case where other human-caused mortality is exceeding PBR, as described 
in the last paragraph) by some small amount and still make a negligible 
impact determination under section 101(a)(5)(A).
    We note that on June 17, 2020, NMFS finalized new Criteria for 
Determining Negligible Impact under MMPA section 101(a)(5)(E). The 
guidance explicitly notes the differences in the negligible impact 
determinations required under section 101(a)(5)(E), as compared to 
sections 101(a)(5)(A) and 101(a)(5)(D), and specifies that the 
procedure in that document is limited to how the agency conducts 
negligible impact analyses for commercial fisheries under section 
101(a)(5)(E). In this proposed rule, NMFS has described its method for 
considering PBR to evaluate the effects of potential mortality in the 
negligible impact analysis. NMFS has reviewed the 2020 guidance and 
determined that our consideration of PBR in the evaluation of mortality 
as described above and in the proposed rule remains appropriate for use 
in the negligible impact analysis for the Action proponent's activities 
under section 101(a)(5)(A).
    Our evaluation of the M/SI for each of the species and stocks for 
which mortality or serious injury could occur follows.
    We first consider maximum potential incidental M/SI from the Action 
Proponents' vessel strike analysis for the affected large whales (table 
79) and from the Action Proponents' explosive detonations for the 
affected small cetaceans (table 80) in consideration of NMFS' threshold 
for identifying insignificant M/SI take. By considering the maximum 
potential incidental M/SI in relation to PBR and ongoing sources of 
anthropogenic mortality, as described above, we begin our evaluation of 
whether the potential incremental addition of M/SI through vessel 
strikes and explosive detonations may affect the species' or stocks' 
annual rates of recruitment or survival. We also consider the 
interaction of those mortalities with incidental taking of that species 
or stock by harassment pursuant to the specified activity.
    Based on the methods discussed previously, NMFS is proposing to 
authorize six mortalities of large whales due to vessel strike over the 
course of the 7-year rule, three by each Action Proponent. Across the 
7-year duration of the rule, two takes by mortality (annual average of 
0.29 takes) of fin whale (Western North Atlantic stock), minke whale 
(Canadian East Coast stock), sei whale (Nova Scotia stock), and sperm 
whale (North Atlantic stock) could occur and are proposed for 
authorization table 79); one take by mortality (annual average of 0.14 
takes) of the Northern Gulf of America stock of sperm whale could occur 
and is proposed for authorization; four takes by mortality (annual 
average of 0.57 takes) of humpback whale (Gulf of Maine stock) could 
occur and are proposed for authorization (table 79). To calculate the 
annual average of M/SI by vessel strike, we divided the 7-year proposed 
take by serious injury or mortality by seven.

[[Page 20016]]



                                                        Table 79--Summary Information Related to Mortalities Requested for Vessel Strike
                                                                                           [2025-2032]
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                                          Annual        7-Year
                                                                                                                                                                         proposed      proposed
                                                                                     Fisheries                       NEFSC            Residual                            take by      take by
                                                                       Total    interactions  (Y/N);  Annual  M/  authorized         PBR  (PBR    Recent UME  (Y/N);      serious      serious
            Common name                     Stock            Stock     annual   annual rate  of M/SI  SI due  to      take     PBR      minus         number of          injury or    injury or
                                                           abundance    M/SI      from  fisheries       vessel     (annual)          annual  M/   strandings,  year      mortality    mortality
                                                                        \a\         interactions       collision      \b\             SI) \c\          declared         (all action  (all action
                                                                                                                                                                        proponents)
                                                                                                                                                                            \d\      proponents)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Fin Whale.........................  Western North              6,802     2.05  Y; 1.45                       0.6           0     11       8.95  N                              0.29            2
                                     Atlantic.
Humpback Whale....................  Gulf of Maine.......       1,396    12.15  Y; 7.75                       4.4           0     22       9.85  Y; 244, 2017                   0.57            4
Minke Whale.......................  Canadian Eastern          21,968     9.40  Y; 8.6                        0.8           1    170      159.6  Y; 198, 2018                   0.29            2
                                     Coastal.
Sei Whale.........................  Nova Scotia.........       6,292     0.60  Y; 0.4                          0           0    6.2        5.6  N                              0.29            2
Sperm Whale.......................  North Atlantic......       5,895     0.20  N                               0           0   9.28       9.08  N                              0.29            2
Sperm Whale *.....................  Northern Gulf of           1,614     9.60  Y; 0.2                          0           0      2       -7.6  N                              0.14        \e\ 1
                                     America.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Unk = Unknown; N/A = Not Applicable.
* Stock abundance from NMSDD (see table 2.4-1 in appendix A of the application).
\a\ This column represents the total number of incidents of M/SI that could potentially accrue to the specified species or stock.
\b\ This column represents the annual authorized take by mortality in the 2021 LOA for Northeast Fisheries Science Center Fisheries Research Activities. No take of large whales was authorized
  in the 2020 LOA for Southeast Fisheries Science Center Fisheries Research Activities.
\c\ This value represents the calculated PBR less the average annual estimate of ongoing anthropogenic mortalities (i.e., total annual human-caused M/SI, which is presented in the SARs).
\d\ This column represents the annual take by serious injury or mortality during Navy training and testing activities and was calculated by the number of mortalities proposed for authorization
  divided by 7 years.
\e\ Authorized for U.S. Navy only.


[[Page 20017]]

    The Action Proponents also requested a small number of takes by M/
SI from explosives. Across the 7-year duration of the rule, NMFS is 
proposing to authorize five takes by M/SI (annual average of 0.71 
takes) of pantropical spotted dolphin (Northern Gulf of America stock), 
two takes by M/SI (annual average of 0.29 takes) of striped dolphin 
(Northern Gulf of America stock), two takes by M/SI (annual average of 
0.29 takes) of bottlenose dolphin (Western North Atlantic Offshore 
stock), one take by M/SI (annual average of 0.14 takes) of Tamanend's 
bottlenose dolphin (Western North Atlantic South Carolina/Georgia 
Coastal), and three takes by M/SI (annual average of 0.43 takes) of 
Clymene dolphin (Western North Atlantic stock) (table 80). To calculate 
the annual average of M/SI from explosives, we divided the 7-year 
proposed take by serious injury or mortality by seven (table 80), the 
same method described for vessel strikes.

[[Page 20018]]



                                                    Table 80--Summary Information Related to AFTT Serious Injury or Mortality From Explosives
                                                                                           [2025-2032]
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                        Annual        7-Year
                                                                                                                                                       proposed      proposed
                                                                             Fisheries         SEFSC       NEFSC            Residual    Recent UME      take by      take by
                                                                 Total   interactions  (Y/  authorized  authorized         PBR  (PBR      (Y/N);        serious      serious
            Species                   Stock           Stock     annual    N);  annual rate      take        take     PBR      minus     number of      injury or    injury or   Population trend
                                                    abundance  M/SI \a\     of M/SI from     (annual)    (annual)          annual  M/  strandings,     mortality    mortality
                                                                             fisheries          \b\         \b\             SI) \c\   year declared   (all action  (all action
                                                                            interactions                                                              proponents)
                                                                                                                                                          \d\      proponents)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Pantropical spotted dolphin...  Northern Gulf of       37,195       241  N                         0.8           0    304       62.2  N                      0.71            5  Potentially
                                 America.                                                                                                                                        increasing.
Striped dolphin *.............  Northern Gulf of        7,782        13  N                         0.6           0     12       -1.6  N                      0.29            2  Unk.
                                 America.
Bottlenose dolphin *..........  Western North         150,704        28  Y; 28                     0.8         1.6    507      476.6  N                      0.29            2  Stable,
                                 Atlantic                                                                                                                                        potentially
                                 Offshore.                                                                                                                                       decreasing.
Tamanend's bottlenose dolphin.  Western North           9,121   0.2-0.6  Y; 0.2-0.6                0.6           0     73       71.8  N                      0.14            1  Unk
                                 Atlantic, South/                                                                                                                                (insufficient
                                 Carolina Georgia                                                                                                                                data).
                                 Coastal.
Clymene dolphin...............  Western North          21,778         0  N                           0           0    126        126  N                      0.43            3  Unk.
                                 Atlantic.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Unk = Unknown, SEFSC = Southeast Fisheries Science Center, NEFSC = Northeast Fisheries Science Center.
* Stock abundance from NMSDD (see table 2.4-1 in appendix A of the application).
\a\ This column represents the total number of incidents of M/SI that could potentially accrue to the specified species or stock.
\b\ These columns represents the annual authorized take by mortality in the 2020 LOA for Southeast Fisheries Science Center Fisheries Research Activities and the 2021 LOA for Northeast
  Fisheries Science Center Fisheries Research Activities.
\c\ This value represents the calculated PBR less the average annual estimate of ongoing anthropogenic mortalities (i.e., total annual human-caused M/SI, which is presented in the SARs).
\d\ This column represents the annual take by serious injury or mortality during training and testing activities and was calculated by the number of mortalities proposed for authorization
  divided by 7 years.


[[Page 20019]]

Stocks With M/SI From the Specified Activity Below the Insignificance 
Threshold--
    As noted above, for a species or stock with M/SI proposed for 
authorization less than 10 percent of residual PBR, we consider M/SI 
from the specified activities to represent an insignificant incremental 
increase in ongoing anthropogenic M/SI that alone (i.e., in the absence 
of any other take and barring any other unusual circumstances) will 
clearly not adversely affect annual rates of recruitment and survival. 
In this case, as shown in table 79 and table 80, the following species 
or stocks have potential or estimated take by M/SI from vessel strike 
and explosives, respectively, and proposed for authorization below 
their insignificance threshold: fin whale (Western North Atlantic 
stock), humpback whale (Gulf of Maine stock), minke whale (Canadian 
East Coast stock), sei whale (Nova Scotia stock), sperm whale (North 
Atlantic stock), pantropical spotted dolphin (Northern Gulf of America 
Stock), bottlenose dolphin (Western North Atlantic Offshore), 
Tamanend's bottlenose dolphin (Western North Atlantic South Carolina/
Georgia Coastal Stock), Clymene dolphin (Western North Atlantic Stock). 
While the authorized M/SI of humpback whales (Gulf of Maine stock) and 
minke whales (Canadian East Coast stock) are each below the 
insignificance threshold, because of the current UMEs, we further 
address how the authorized M/SI and the UMEs inform the negligible 
impact determinations immediately below. For the other seven stocks 
with authorized M/SI below the insignificance threshold, there are no 
other known factors, information, or unusual circumstances that 
indicate anticipated M/SI below the insignificance threshold could have 
adverse effects on annual rates of recruitment or survival and they are 
not discussed further. For the remaining stocks with potential M/SI 
above the insignificance threshold, how that M/SI compares to residual 
PBR, as well as additional factors, are discussed below as well.
Humpback Whale (Gulf of Maine Stock)
    For this stock, PBR is currently set at 22. The total annual M/SI 
from other sources of anthropogenic mortality is estimated to be 12.15. 
This yields a residual PBR of 9.85. The additional 0.57 annual 
mortalities that are authorized in this rule are below the 
insignificance threshold (10 percent of residual PBR, in this case 
0.985). Nonetheless, since January 2016, elevated humpback whale 
mortalities have occurred along the Atlantic coast from Maine to 
Florida. As of February 6, 2025, there have been 244 known strandings, 
and of the whales examined, about 40 percent had evidence of human 
interaction either from vessel strike or entanglement. NOAA is 
consulting with researchers that are conducting studies on the humpback 
whale populations, and these efforts may provide information on changes 
in whale distribution and habitat use that could provide additional 
insight into how these vessel interactions occurred. However, even in 
consideration of the UME, the incremental increase in annual mortality 
from the Action Proponents' specified activities is not expected to 
adversely affect annual rates of recruitment or survival.
Minke Whale (Canadian East Coast Stock)
    For this stock, PBR is currently set at 170. The total annual M/SI 
from other sources of anthropogenic mortality is estimated to be 9.4. 
In addition, 1 annual mortality has been authorized for this same stock 
in the current incidental take regulations for NMFS' Northeast 
Fisheries Science Center (86 FR 58434, October 21, 2021). This yields a 
residual PBR of 159.6. The additional 0.29 annual mortalities that are 
authorized in this rule are well below the insignificance threshold (10 
percent of residual PBR, in this case 16.0). Nonetheless, minke whale 
mortalities detected along the Atlantic coast from Maine through South 
Carolina resulted in the declaration of an on-going UME in 2017. 
Preliminary findings show evidence of human interactions or infectious 
disease, but these findings are not consistent across all of the minke 
whales examined, so more research is needed. As of February 10, 2025, a 
total of 198 minke whales have stranded during this UME, averaging 
about 25 animals per year. However, even in consideration of the UME, 
the incremental increase in annual mortality from the Action 
Proponents' activities is not expected to adversely affect annual rates 
of recruitment or survival.
Stocks With M/SI From the Specified Activity Above the Insignificance 
Threshold (and, in This Case, Also Above Residual PBR)--
Sperm Whale (Northern Gulf of America Stock)
    For the Northern Gulf of America stock of sperm whale, PBR is 
currently set at 2 and the total annual M/SI is estimated at 9.6, 
yielding a residual PBR of -7.6. NMFS is proposing to authorize one M/
SI (U.S. Navy only) over the 7-year duration of the rule (indicated as 
0.14 annually for the purposes of comparing to PBR and evaluating 
overall effects on annual rates of recruitment and survival), which 
means that residual PBR is exceeded by 7.74. However, as described 
above, given that the negligible impact determination is based on the 
assessment of take of the activity being analyzed, when total annual 
mortality from human activities is higher, but the impacts from the 
specific activity being analyzed are very small, NMFS may still find 
the impact of the authorized take from a specified activity to be 
negligible even if total human-caused mortality exceeds PBR--
specifically if the authorized mortality is less than 10 percent of PBR 
and management measures are being taken to address serious injuries and 
mortalities from the other activities causing mortality (i.e., other 
than the specified activities covered by the incidental take 
authorization in consideration). When those considerations are applied 
here, the authorized lethal take (0.14 annually) of Northern Gulf of 
America stock of sperm whale is less than 10 percent of PBR (PBR is 2). 
Additionally, there are management measures in place to address M/SI 
from activities other than those the Action Proponents are conducting 
(as discussed below). Immediately below, we explain the information 
that supports our finding that the M/SI proposed for authorization 
herein is not expected to result in more than a negligible impact on 
this stock. As described previously, NMFS must also ensure that impacts 
by the applicant on the species or stock from other types of take 
(i.e., harassment) do not combine with the impacts from mortality to 
adversely affect the species or stock via impacts on annual rates of 
recruitment or survival, which we have done further below in the stock-
specific conclusion sections.
    As discussed, we also take into consideration management measures 
in place to address M/SI caused by other activities. As reported in the 
SAR, of the total annual M/SI of this stock (9.6), 9.4 of those M/SI 
are from the DWH oil spill. (The remaining 0.2 are fishery-related M/
SI.) Since the DWH spill, there have been numerous recovery efforts for 
marine mammals. The DWH oil spill NRDA settlement allocated 
$144,000,000 to marine mammal restoration, and as of 2021, $30,968,016 
has been allocated (DWH NRDA Trustees, 2021). Projects have focused

[[Page 20020]]

on understanding and assessing Gulf cetacean populations, enhancing the 
capacity of stranding and response programs, enhancing our 
understanding of, and reducing, stressors on cetaceans, and developing 
and implementing decision support tools for cetaceans. Recovery efforts 
have included some efforts to minimize impacts to marine mammals from 
ocean noise. Proposals and planning for additional pilot projects, 
including projects to test existing alternatives to traditional airgun 
seismic surveys, engineering solutions for vessel quieting, and 
operational approaches for quieting commercial vessels while underway 
(Southall et al. 2024).
    In this case, 0.14 M/SI means one mortality in 1 of the 7 years and 
zero mortalities in 6 of those 7 years. Therefore, the Action 
Proponents would not be contributing to the total human-caused 
mortality at all in 6 of the 7, or 85.7 percent, of the years covered 
by this rulemaking. That means that even if a Northern Gulf of America 
stock of sperm whale were to be taken by mortality from vessel strike, 
in 6 of the 7 years there could be no effect on annual rates of 
recruitment or survival from Action Proponent-caused M/SI. 
Additionally, the loss of a male would have far less, if any, effect on 
population rates and absent any information suggesting that one sex is 
more likely to be struck than another, we can reasonably assume that 
there is a 50 percent chance that the single strike authorized by this 
rulemaking would be a male, thereby further decreasing the likelihood 
of impacts on the population rate. In situations like this where 
potential M/SI is fractional, consideration must be given to the 
lessened impacts anticipated due to the absence of M/SI in 6 of the 7 
years and the fact that the single strike could be a male. Lastly, we 
reiterate that PBR is a conservative metric and also not sufficiently 
precise to serve as an absolute predictor of population effects upon 
which mortality caps would appropriately be based. This is especially 
important given the minor difference between zero and one across the 7-
year period covered by this rulemaking, which is the smallest 
distinction possible when considering mortality. As noted above, Wade 
et al. (1998) (authors of the paper from which the current PBR equation 
is derived) note, ``Estimating incidental mortality in 1 year to be 
greater than the PBR calculated from a single abundance survey does not 
prove the mortality will lead to depletion; it identifies a population 
worthy of careful future monitoring and possibly indicates that 
mortality-mitigation efforts should be initiated.'' Importantly, M/SI 
proposed for authorization is below 10 percent of PBR, and management 
actions are in place to support recovery of the stock following the DWH 
oil spill impacts. Based on the presence of the factors described 
above, we do not expect lethal take from Navy activities, alone, to 
adversely affect Northern Gulf of America stock of sperm whales through 
effects on annual rates of recruitment or survival. Nonetheless, the 
fact that total human-caused mortality exceeds PBR necessitates close 
attention to the remainder of the impacts (i.e., harassment) on the 
Northern Gulf of America stock of sperm whale from the Action 
Proponents' activities to ensure that the total authorized takes have a 
negligible impact on the species or stock. Therefore, this information 
will be considered in combination with our assessment of the impacts of 
authorized harassment takes in the Group and Species-Specific Analyses 
section that follows.
Striped Dolphin (Northern Gulf of America Stock)
    For striped dolphin (Northern Gulf of America stock), PBR is 
currently set at 12 and the total annual M/SI is estimated at greater 
than or equal to 13. As described in the SAR, these 13 M/SI are 
predicted M/SI from the DWH oil spill. In addition, 0.6 annual 
mortalities have been authorized for this same stock in the current 
incidental take regulations for NMFS' Southeast Fisheries Science 
Center (85 FR 27028, May 6, 2020). This yields a residual PBR of -1.6. 
NMFS is proposing to authorize two M/SI for the Navy over the 7-year 
duration of the rule (indicated as 0.29 annually for the purposes of 
comparing to PBR and evaluating overall effects on annual rates of 
recruitment and survival), which means that residual PBR is exceeded by 
1.74. However, as described above, given that the negligible impact 
determination is based on the assessment of take of the activity being 
analyzed, when total annual mortality from human activities is higher, 
but the impacts from the specific activity being analyzed are very 
small, NMFS may still find the impact of the authorized take from a 
specified activity to be negligible even if total human-caused 
mortality exceeds PBR--specifically if the authorized mortality is less 
than 10 percent of PBR and management measures are being taken to 
address serious injuries and mortalities from the other activities 
causing mortality (i.e., other than the specified activities covered by 
the incidental take authorization in consideration). When those 
considerations are applied here, the authorized lethal take (0.29 
annually) of Northern Gulf of America stock of striped dolphin is less 
than 10 percent of PBR (PBR is 12). Additionally, there are management 
measures in place to address M/SI from activities other than those the 
Action Proponents are conducting (as discussed below). Immediately 
below, we explain the information that supports our finding that the M/
SI proposed for authorization herein is not expected to result in more 
than a negligible impact on this stock. As described previously, NMFS 
must also ensure that impacts by the applicant on the species or stock 
from other types of take (i.e., harassment) do not combine with the 
impacts from mortality to adversely affect the species or stock via 
impacts on annual rates of recruitment or survival, which we have done 
further below in the stock-specific conclusion sections.
    As discussed, we also take into consideration management measures 
in place to address M/SI caused by other activities. As reported in the 
SAR, all 13 of the total annual M/SI of this stock are from the DWH oil 
spill. As described in the previous section in more detail, since the 
DWH spill, there have been numerous recovery efforts for marine 
mammals, including some efforts to minimize impacts to marine mammals 
from ocean noise, such as pilot projects to test existing alternatives 
to traditional airgun seismic surveys, engineering solutions for vessel 
quieting, and operational approaches for quieting commercial vessels 
while underway (Southall et al. 2024).
    Additionally of note, in this case, 0.29 M/SI means one mortality 
in 1 of the 7 years and zero mortalities in 6 of those 7 years. 
Therefore, the Action Proponents would not be contributing to the total 
human-caused mortality at all in 6 of the 7, or 85.7 percent, of the 
years covered by this rulemaking. That means that even if a striped 
dolphin were to be taken by mortality from explosives, in 6 of the 7 
years there could be no effect on annual rates of recruitment or 
survival from Action Proponent-caused M/SI. Additionally, the loss of a 
male would have far less, if any, effect on population rates and absent 
any information suggesting that one sex is more likely to be injured 
than another, we can reasonably assume that there is a 50 percent 
chance that the two mortalities authorized by this rulemaking would be 
a male, thereby further decreasing the likelihood of impacts on the 
population rate. In

[[Page 20021]]

situations like this where potential M/SI is fractional, consideration 
must be given to the lessened impacts anticipated due to the absence of 
M/SI in 6 of the 7 years and the fact that the single strike could be a 
male. Lastly, we reiterate that PBR is a conservative metric and also 
not sufficiently precise to serve as an absolute predictor of 
population effects upon which mortality caps would appropriately be 
based. This is especially important given the minor difference between 
zero and one across the 7-year period covered by this rulemaking, which 
is the smallest distinction possible when considering mortality. As 
noted previously, Wade et al. (1998) state, ``Estimating incidental 
mortality in 1 year to be greater than the PBR calculated from a single 
abundance survey does not prove the mortality will lead to depletion; 
it identifies a population worthy of careful future monitoring and 
possibly indicates that mortality-mitigation efforts should be 
initiated.'' Further, M/SI proposed for authorization is below 10 
percent of PBR, and management actions are in place to support recovery 
of the stock following the DWH oil spill impacts. Based on the presence 
of the factors described above, we do not expect lethal take from Navy 
activities, alone, to adversely affect Northern Gulf of America stock 
of striped dolphins through effects on annual rates of recruitment or 
survival. Nonetheless, the fact that total human-caused mortality 
exceeds PBR necessitates close attention to the remainder of the 
impacts (i.e., harassment) on the Northern Gulf of America stock of 
striped dolphins from the Action Proponents' activities to ensure that 
the total authorized takes have a negligible impact on the species or 
stock. Therefore, this information will be considered in combination 
with our assessment of the impacts of authorized harassment takes in 
the Group and Species-Specific Analyses section that follows.

Deepwater Horizon Oil Spill

    As discussed in the earlier Deepwater Horizon Oil Spill section, 
the DWH oil spill caused a suite of adverse health effects to marine 
mammals in the GOM. Coastal and estuarine bottlenose dolphin 
populations were some of the most severely injured (Hohn et al., 2017; 
Rosel et al., 2017; Thomas et al., 2017), but oceanic species were also 
exposed and experienced increased mortality, increased reproductive 
failure, and a higher likelihood of other adverse health effects.
    Due to the scope of the spill, the magnitude of potentially injured 
populations, and the difficulties and limitations of working with 
marine mammals, it is impossible to quantify injury without 
uncertainty. Wherever possible, the quantification results represent 
ranges of values that encapsulate the uncertainty inherent in the 
underlying datasets. The population model outputs shown in table 15 
best represent the temporal magnitude of the injury and the potential 
recovery time from the injury (DWH NRDA Trustees, 2016). The values in 
the table inform the baseline levels of both individual health and 
susceptibility to additional stressors, as well as stock status, with 
which the effects of the Action Proponents' takes are considered in the 
negligible impact analysis. Additionally, estimates of annual mortality 
for many stocks now include mortality attributed to the effects of the 
DWH oil spill (see table 15) (Hayes et al., 2024), and these mortality 
estimates are considered as part of the environmental baseline.

Group and Species-Specific Analyses

    In this section, we build on the general analysis that applies to 
all marine mammals in the AFTT Study Area from the previous sections. 
We first include information and analysis that applies to mysticetes 
or, separately, odontocetes, or pinnipeds, and then within those three 
sections, more specific information that applies to smaller groups, 
where applicable, and the affected species or stocks. The specific 
authorized take numbers are also included in the analyses below, and so 
here we provide some additional context and discussion regarding how we 
consider the authorized take numbers in those analyses.
    The maximum amount and type of incidental take of marine mammals 
reasonably likely to occur and therefore proposed to be authorized from 
exposures to sonar and other active acoustic sources and explosions 
during the 7-year activity period are shown in table 35, table 36, and 
table 37, and the subset attributable to ship shock trials is included 
in table 45.
    In the discussions below, the estimated takes by Level B harassment 
represent instances of take, not the number of individuals taken (the 
much lower and less frequent Level A harassment takes are far more 
likely to be associated with separate individuals), and in some cases 
individuals may be taken more than one time. As part of our evaluation 
of the magnitude and severity of impacts to marine mammal individuals 
and the species, and specifically in an effort to better understand the 
degree to which the modeled and estimated takes likely represent 
repeated takes of the individuals of a given species/stock, we consider 
the total annual numbers of take by harassment (auditory injury, non-
auditory injury, TTS, and behavioral disturbance) for species or stocks 
as compared to their associated abundance estimates--specifically, take 
numbers higher than the stock abundance clearly indicate that some 
number of individuals are being taken on more than one day in the year, 
and broadly higher or lower ratios of take to abundance may reasonably 
be considered to equate to higher or lower likelihood of repeated 
takes, respectively, other potentially influencing factors being equal. 
In addition to the mathematical consideration of estimated take 
compared to abundance, we also consider other factors or circumstances 
that may influence the likelihood of repeated takes, where known, such 
as circumstances where activities resulting in take are focused in an 
area and time (e.g., instrumented ranges or a homeport, or long-
duration activities such as manor training exercises) and/or where the 
same individual marine mammals are known to congregate over longer 
periods of time (e.g., pinnipeds at a haulout, mysticetes in a known 
foraging area, or resident odontocetes with smaller home ranges). 
Similarly, and all else being equal, estimated takes that are largely 
focused in one region and/or season (see table 81, table 83, table 85, 
table 87, table 89, and table 91) may indicate a higher likelihood of 
repeated takes of the same individuals.
    Occasional, milder behavioral responses are unlikely to cause long-
term consequences for individual animals or populations, and even if 
some smaller subset of the takes are in the form of a longer (several 
hours or a day) and more severe response, if they are not expected to 
be repeated over a comparatively longer duration of sequential days, 
impacts to individual fitness are not anticipated. Nearly all studies 
and experts agree that infrequent exposures of a single day or less are 
unlikely to impact an individual's overall energy budget (Farmer et 
al., 2018; Harris et al., 2017; King et al., 2015; NAS 2017; New et 
al., 2014; Southall et al., 2007; Villegas-Amtmann et al., 2015; 
Hoekendijk et al., 2018; Wisniewska et al., 2018; Czapanskiy et al., 
2021; Pirotta, 2022). Generally speaking, and in the case of most 
species impacted by the proposed activities, in the cases where some 
number of individuals may reasonably be expected to be taken on more 
than one day within a year, that number of

[[Page 20022]]

days would be comparatively small and also with no reason to expect 
that those takes would occur on sequential days. In the rarer cases of 
species where individuals might be expected to be taken on a 
comparatively higher number of days of the year and there are reasons 
to think that these days might be sequential or clumped together, the 
likely impacts of this situation are discussed explicitly in the 
species discussions.
    To assist in understanding what this analysis means, we clarify a 
few issues related to estimated takes and the analysis here. An 
individual that incurs AUD INJ or TTS may sometimes, for example, also 
be subject to behavioral disturbance at the same time. As described 
above in this section, the degree of auditory injury, and the degree 
and duration of TTS, expected to be incurred from the Navy's activities 
are not expected to impact marine mammals such that their reproduction 
or survival could be affected. Similarly, data do not suggest that a 
single instance in which an animal accrues auditory injury or TTS and 
is also subjected to behavioral disturbance would result in impacts to 
reproduction or survival. Alternately, we recognize that if an 
individual is subjected to behavioral disturbance repeatedly for a 
longer duration and on consecutive days, effects could accrue to the 
point that reproductive success is impacted. Accordingly, in analyzing 
the number of takes and the likelihood of repeated and sequential 
takes, we consider the total takes, not just the takes by Level B 
harassment by behavioral disturbance, so that individuals potentially 
exposed to both threshold shift and behavioral disturbance are 
appropriately considered. The number of takes by Level A harassment by 
auditory injury are so low (and zero in some cases) compared to 
abundance numbers that it is considered highly unlikely that any 
individual would be taken at those levels more than once.
    Use of sonar and other transducers would typically be transient and 
temporary. The majority of acoustic effects to most marine mammal 
stocks from sonar and other active sound sources during the specified 
military readiness activities would be primarily from anti-submarine 
warfare events. On the less severe end, exposure to comparatively lower 
levels of sound at a detectably greater distance from the animal, for a 
few or several minutes, could result in a behavioral response such as 
avoiding an area that an animal would otherwise have moved through or 
fed in, or breaking off one or a few feeding bouts. More severe 
behavioral effects could occur when an animal gets close enough to the 
source to receive a comparatively higher level of sound, is exposed 
continuously to one source for a longer time, or is exposed 
intermittently to different sources throughout a day. Such effects 
might result in an animal having a more severe flight response and 
leaving a larger area for a day or more, or potentially losing feeding 
opportunities for a day. However, such severe behavioral effects are 
expected to occur infrequently. In addition to the proximity to the 
source, the type of activity and the season and location during which 
an animal is exposed, can inform the impacts. These factors, including 
the numbers and types of effects that are estimated in areas known to 
be biologically important for certain species are discussed in the 
group and species-specific sections, below.
    Further, as described in the Proposed Mitigation Measures section, 
this proposed rule includes mitigation measures that would reduce the 
probability and/or severity of impacts expected to result from acute 
exposure to acoustic sources or explosives, vessel strike, and impacts 
to marine mammal habitat. Specifically, the Action Proponents would use 
a combination of delayed starts, powerdowns, and shutdowns to avoid 
mortality or serious injury, minimize the likelihood or severity of AUD 
INJ or non-auditory injury, and reduce instances of TTS or more severe 
behavioral disturbance caused by acoustic sources or explosives. The 
Action Proponents would also implement multiple time/area restrictions 
that would reduce take of marine mammals in areas or at times where 
they are known to engage in important behaviors, such as calving, where 
the disruption of those behaviors would have a higher probability of 
resulting in impacts on reproduction or survival of individuals that 
could lead to population-level impacts.
    These time/area restrictions include ship shock trial mitigation 
areas throughout the Study Area, MTE Planning Awareness Mitigation 
Areas in the Northeast and Mid-Atlantic, a Gulf of Maine Marine Mammal 
Mitigation Area, several mitigation areas specific to NARW, and a 
Rice's Whale Mitigation Area. Mitigation areas for NARW and Rice's 
whale specifically are discussed in those species-specific sections 
below. However, it is important to note that measures in those areas, 
while developed to protect those species, would also benefit other 
marine mammals in those areas. Therefore, they are discussed here also.
    Regarding ship shock trials, the Action Proponents will not conduct 
ship shock trials within the Rice's whale core distribution area in the 
northern Gulf of America or within the portion of the ship shock trial 
box that overlaps the Jacksonville OPAREA from November 15 through 
April 15. These mitigation measures would avoid potential exposure of 
Rice's whales to injurious levels of sound and avoid potential 
injurious and behavioral impacts to NARW during calving season. 
Additionally, pre-event planning for ship shock trials will include the 
selection of sites where marine mammal abundance is expected to be the 
lowest during the planned event and prioritize sites more than 2 nmi 
(3.7 km) from the western boundary of the Gulf Stream where marine 
mammals would be expected in greater concentrations for foraging and 
migration. Overall, the benefits of Ship Shock Trial Mitigation Areas 
would be substantial for all marine mammal taxa because ship shock 
trials use the largest NEW of any explosive activity conducted in the 
AFTT Study Area.
    Regarding MTEs, the Action Proponents will not conduct any MTEs or 
any portion of any MTE in the Major Training Exercise Planning 
Awareness Mitigation Areas in the northeast. This would restrict MTEs 
from occurring within NARW foraging critical habitat, on Georges Bank, 
and in areas that contain underwater canyons (e.g., Hydrographer 
Canyon, and a portion of the Northeast Canyons and Seamounts National 
Marine Monument), as these locations have been associated with high 
marine mammal abundance, feeding, and mating. In the Major Training 
Exercise Planning Awareness Mitigation Areas in the mid-Atlantic, the 
Action Proponents will not conduct any MTEs or any portion of any MTE 
to the maximum extent practicable, and would conduct no more than four 
(or a portion of more than four) MTEs per year. This would restrict the 
number of MTEs that could occur within large swaths of shelf break that 
contain underwater canyons or other habitats (e.g., Norfolk Canyon, 
part of the Cape Hatteras Special Research Area) associated with high 
marine mammal diversity in this region.
    In the Gulf of Maine Marine Mammal Mitigation Area, the Action 
Proponents would use no more than 200 hours of surface ship hull-
mounted MFAS annually. This measure is designed to reduce exposure of 
marine mammals to potentially injurious levels of sound from surface 
ship hull-mounted MFAS, the type of active sonar with the highest power 
source used in the Study Area.

[[Page 20023]]

    Additionally, the action proponents would implement four mitigation 
areas specifically designed to protect NARW. These include the 
Northeast North Atlantic Right Whale Mitigation Area, Jacksonville 
Operating Area North Atlantic Right Whale Mitigation Area, Southeast 
North Atlantic Right Whale Mitigation Area, and the Dynamic North 
Atlantic Right Whale Mitigation Areas. These areas are designed to 
reduce exposure of NARWs to acoustic and explosive stressors as well as 
vessel strike risk in foraging critical habitat, reproduction critical 
habitat, and in areas and times when the species has a higher 
occurrence in these areas. The Northeast North Atlantic Right Whale 
Mitigation Area would also protect other marine mammal species, 
including those with BIAs that overlap the mitigation area, including 
fin whale, humpback whale, minke whale, sei whale, and harbor porpoise 
(LaBrecque et al., 2015).
    In addition to the nature and context of the disturbance, including 
whether take occurs in a known BIA, species-specific factors affect the 
severity of impacts to individual animals and population consequences 
of disturbance. Keen et al. (2021) identifies three population 
consequences of disturbance themes: life history traits, environmental 
conditions, and disturbance source characteristics. Life history traits 
considered in Keen et al. (2021) include movement ecology (whether 
animals are resident, nomadic, or migratory), reproductive strategy 
(capital breeders, income breeders, or mixed), body size (based on size 
and life stage), and pace of life (slow or fast).
    Regarding movement ecology, resident animals that have small home 
ranges relative to the size and duration of an impact zone would have a 
higher risk of repeated exposures to an ongoing activity. Animals that 
are nomadic over a larger range may have less predictable risk of 
repeated exposure. For resident and nomadic populations, overlap of a 
stressor with feeding or reproduction depends more on time of year 
rather than location in their habitat range. In contrast, migratory 
animals may have higher or reduced potential for exposure during 
feeding and reproduction based on both location, time of the year, and 
duration of an activity. The risk of repeated exposure during 
individual events may be lower during migration as animals maintain 
directed transit through an area.
    Reproduction is energetically expensive for female marine mammals, 
and reproductive strategy can influence an animal's sensitivity to 
disturbance. Mysticetes and phocids are capital breeders. Capital 
breeders rely on their capital, or energy stores, to migrate, maintain 
pregnancy, and nurse a calf. Capital breeders would be more resilient 
to short-term foraging disruption due to their reliance on built-up 
energy reserves, but are vulnerable to prolonged foraging impacts 
during gestation. Otariids and most odontocetes are income breeders, 
which rely on some level of income, or regular foraging, to give birth 
and nurse a calf. Income breeders would be more sensitive to the 
consequences of disturbances that impact foraging during lactation. 
Some species exhibit traits of both, such as beaked whales.
    Smaller animals require more food intake per unit body mass than 
large animals. They must consume food on a regular basis and are likely 
to be non-migratory and income breeders. The smallest odontocetes, the 
porpoises, must maintain high metabolisms to maintain thermoregulation 
and cannot rely on blubber stores for long periods of time, whereas 
larger odontocetes can more easily thermoregulate. The larger size of 
other odontocetes is an adaptation for deep diving that allows them to 
access high quality mesopelagic and bathypelagic prey. Both small and 
large odontocetes have lower foraging efficiency than the large whales. 
The filter-feeding large whales (mysticetes) consume most of their food 
within several months of the year and rely on extensive lipid reserves 
for the remainder of the year. The metabolism of mysticetes allows for 
fasting while seeking prey patches during foraging season and prolonged 
periods of fasting outside of foraging season (Goldbogen et al., 2023). 
Their energy stores support capital breeding and long migrations. The 
effect of a temporary feeding disturbance is likely to have 
inconsequential impacts to a mysticete but may be consequential for 
small cetaceans. Despite their relatively smaller size, amphibious 
pinnipeds have lower thermoregulatory requirements because they spend a 
portion of time on land. For purposes of this assessment, marine 
mammals were generally categorized as small (less than 10 ft (3.05 m)), 
medium (10-30 ft (3.05-9.1 m)), or large (more than 30 ft (9.1 m)) 
based on length.
    Populations with a fast pace of life are characterized by early age 
of maturity, high birth rates, and short life spans, whereas 
populations with a slow pace of life are characterized by later age of 
maturity, low birth rates, and long life spans. The consequences of 
disturbance in these populations differ. Although reproduction in 
populations with a fast pace of life are more sensitive to foraging 
disruption, these populations are quick to recover. Reproduction in 
populations with a slow pace of life is resilient to foraging 
disruption, but late maturity and low birth rates mean that long-term 
impacts to breeding adults have a longer-term effect on population 
growth rates. Pace of life was categorized for each species in this 
analysis by comparing age at sexual maturity, birth rate interval, life 
span, body size, and feeding and reproductive strategy.
    Southall et al. (2023) also identified factors that inform a 
population's vulnerability. The authors describe a framework to assess 
risk to populations from specific industry impact scenarios at 
different locations or times of year. While this approach may not be 
suitable for many military readiness activities, for which alternate 
spatial or seasonal scenarios are not usually feasible, the concepts 
considered in that framework's population vulnerability assessment are 
useful in this analysis, including population status (endangered or 
threatened), population trend (decreasing, stable, or increasing), 
population size, and chronic exposure to other anthropogenic or 
environmental stressors (e.g., fisheries interactions, pollution, 
climate change, etc.). These factors are also considered when assessing 
the overall vulnerability of a stock to repeated effects from acoustic 
and explosive stressors.
    In consideration of the factors outlined above, if impacts to 
individuals increase in magnitude or severity such that repeated and 
sequential higher severity impacts occur (the probability of this goes 
up for an individual the higher total number of takes it has) or the 
total number of moderate to more severe impacts increases 
substantially, especially if occurring across sequential days, then it 
becomes more likely that the aggregate effects could potentially 
interfere with feeding enough to reduce energy budgets in a manner that 
could impact reproductive success via longer cow-calf intervals, 
terminated pregnancies, or calf mortality. It is important to note that 
these impacts only accrue to females, which only comprise approximately 
50 percent of the population. Based on energetic models, it takes 
energetic impacts of a significantly greater magnitude to cause the 
death of an adult marine mammal, and females will always terminate a 
pregnancy or stop lactating before allowing their health to 
deteriorate. Also, the death of an adult female has significantly more 
impact on population growth rates than reductions in reproductive 
success, while the death of an adult male has very little effect on

[[Page 20024]]

population growth rates. However, as explained earlier, such severe 
impacts from the specified activities would be very infrequent and not 
considered likely to occur at all for most species and stocks. We note 
that the negligible impact analysis is inherently a two-tiered 
assessment that first evaluates the anticipated impacts of the 
activities on marine mammals individuals, and then if impacts are 
expected to reproduction or survival of any individuals further 
evaluates the effects of those individual impacts on rates of 
reproduction and survival of the species or stock, in the context of 
the status of the species or stock. The analyses below in some cases 
address species collectively if they occupy the same functional hearing 
group (i.e., very-low, low, high, and very high-frequency cetaceans), 
share similar life history strategies, and/or are known to behaviorally 
respond similarly to acoustic stressors. Because some of these groups 
or species share characteristics that inform the impact analysis 
similarly, it would be duplicative to repeat the same analysis for each 
species. In addition, similar species typically have the same hearing 
capabilities and behaviorally respond in the same manner.
    Thus, our analysis below considers the effects of the specified 
activities on each affected species or stock even where discussion is 
organized by functional hearing group and/or information is evaluated 
at the group level. Where there are meaningful differences between a 
species or stock that would further differentiate the analysis, they 
are either described within the section or the discussion for those 
species or stocks is included as a separate subsection. Specifically 
below, we first give broad descriptions of the mysticete, odontocete, 
and pinniped groups and then differentiate into further groups as 
appropriate.
Mysticetes
    This section builds on the broader discussion above and brings 
together the discussion of the different types and amounts of take that 
different stocks will incur, the applicable mitigation for each stock, 
and the status and life history of the stocks to support the negligible 
impact determinations for each stock. We have already described above 
why we believe the incremental addition of the small number of low-
level auditory injury takes will not have any meaningful effect towards 
inhibiting reproduction or survival. We have also described above in 
this section the unlikelihood of any masking or habitat impacts having 
effects that would impact the reproduction or survival of any of the 
individual marine mammals affected by the Action Proponents' 
activities. For mysticetes, there is no predicted non-auditory injury 
from explosives for any stock. Regarding the severity of individual 
takes by Level B harassment by behavioral disturbance for mysticetes, 
the majority of these responses are anticipated to occur at received 
levels below 172 dB, and last from a few minutes to a few hours, at 
most, with associated responses most likely in the form of moving away 
from the source, foraging interruptions, vocalization changes, or 
disruption of other social behaviors, lasting from a few minutes to 
several hours. Much of the discussion below focuses on the behavioral 
effects and the mitigation measures that reduce the probability or 
severity of effects in biologically important areas or other habitat. 
Because there are multiple stock-specific factors in relation to the 
status of the species, as well as mortality take for several stocks, at 
the end of the section we break out stock-specific findings.
    In table 81 below for mysticetes, we indicate the total annual 
mortality, Level A harassment, and Level B harassment, and a number 
indicating the instances of total take as a percentage of abundance.
    In table 82 below, we indicate the status, life history traits, 
important habitats, and threats that inform our analysis of the 
potential impacts of the estimated take on the affected mysticete 
stocks.

[[Page 20025]]



                     Table 81--Annual Estimated Take by Level B Harassment, Level A Harassment, and Mortality and Related Information for Mysticetes in the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                        Maximum
                                                                                                                                        annual
                                                                                       Maximum      Maximum     Maximum    Maximum    harassment      Season(s) with 40      Region(s) with 40
       Marine mammal species                  Stock          NMFS stock     NMSDD       annual       annual      annual     annual        as         percent of take or      percent of take or
                                                              abundance   abundance    Level B      Level A    mortality     take     percentage           greater                greater
                                                                                      harassment   harassment                          of stock
                                                                                                                                       abundance
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale.........  Western...............       * 372         216          414            2          0        416           112  Spring (45 percent)     Northeast (70
                                                                                                                                                    Winter (40 percent).    percent).
Blue whale.........................  Western North Atlantic       * Unk          19           71            1          0         72           Und  N/A...................  Mid-Atlantic (48
                                                                                                                                                                            percent).
Bryde's whale......................  Primary...............       * N/A         N/A           11            0          0         11           Und  Winter (48 percent)...  High Seas (100
                                                                                                                                                                            percent).
Fin whale..........................  Western North Atlantic     * 6,802       1,075        2,616           21       0.29      2,637            39  N/A...................  Mid-Atlantic (62
                                                                                                                                                                            percent).
Humpback whale.....................  Gulf of Maine.........     * 1,396         690          844           12       0.57     856.57            61  Spring (50 percent)...  Mid-Atlantic (48
                                                                                                                                                                            percent)
                                                                                                                                                                           Northeast (43
                                                                                                                                                                            percent).
Minke whale........................  Canadian East Coast...    * 21,968       1,339        4,643           56       0.29      4,699            21  Winter (51 percent)...  Southeast (47
                                                                                                                                                                            percent).
Rice's whale.......................  Northern Gulf of              * 51         118          303            3          0        306           600  Winter (44 percent)...  Gulf of America (100
                                      America.                                                                                                                              percent).
Sei whale..........................  Nova Scotia...........     * 6,292         316          747            7       0.29     754.29            12  Spring (41 percent)...  N/A.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: N/A = Not Applicable. NMSDD abundances are averages only within the U.S. EEZ.
* Indicates which abundance estimate was used to calculate the maximum annual take as a percentage of abundance, either the NMFS SAR (Hayes et al., 2024) or the NMSDD (table 2.4-1 in appendix
  A of the application). Please refer to the following section for details on which abundance estimate was selected.


                                                                                                           Table 82--Life History Traits, Important Habitat, and Threats to Mysticetes in the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                                                                                                                                                                               Annual
                                                                                                                                                                                                                                                                                                             mortality/
                                                                                                                                                     Reproductive                        Chronic risk     UME, oil spill,   ESA- designated   BIAs (LaBrecque   Other important                                serious
     Marine mammal species            Stock            ESA status        MMPA status      Movement ecology   Movement ecology      Body size           strategy        Pace of life         factors            other       critical habitat    et al. 2015)         habitat      Population trend    PBR    injury (from
                                                                                                                                                                                                                                                                                                             other human
                                                                                                                                                                                                                                                                                                             activities)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale....  Western..........  Endangered.......  Depleted.........  Migratory........  Migratory........  Large............  Capital..........  Slow............  Vessel strikes,   UME (declared     Critical          Yes: Feeding      Great South       Decreasing......     0.73          14.8
                                                                      Strategic........                                                                                                 entanglement,     2017, active).    Habitat:          (n=3),            Channel/Georges
                                                                                                                                                                                        habitat                             Northeastern US   Migration         Bank Shelf
                                                                                                                                                                                        degradation,                        Foraging Area     (n=1),            Break, Gulf of
                                                                                                                                                                                        pollution,                          Unit 1,           Reproduction      ME Mating,
                                                                                                                                                                                        vessel                              Southeastern US   (n=2).            Migratory
                                                                                                                                                                                        disturbance,                        Calving Area                        Corridor
                                                                                                                                                                                        ocean noise,                        Unit 2.                             Scotian Shelf,
                                                                                                                                                                                        climate change.                                                         Southeast
                                                                                                                                                                                                                                                                Atlantic
                                                                                                                                                                                                                                                                Calving,
                                                                                                                                                                                                                                                                Southern New
                                                                                                                                                                                                                                                                England.
Blue whale....................  Western North      Endangered.......  Depleted.........  Migratory........  Migratory........  Large............  Capital..........  Slow............  Vessel strikes,   No..............  No..............  No..............  None identified.  Unk, but              0.8             0
                                 Atlantic.                            Strategic........                                                                                                 entanglement,                                                                             possibly
                                                                                                                                                                                        habitat                                                                                   increasing.
                                                                                                                                                                                        degradation,
                                                                                                                                                                                        pollution,
                                                                                                                                                                                        vessel
                                                                                                                                                                                        disturbance,
                                                                                                                                                                                        ocean noise,
                                                                                                                                                                                        climate change.

[[Page 20026]]

 
Bryde's whale.................  Primary..........  Not Listed.......  .................  Unknown, likely    Unknown, likely    Large............  Capital..........  Slow............  Vessel strikes,   No..............  No..............  No..............  None identified.  Unk.............      N/A           N/A
                                                                                          migratory.         migratory.                                                                 entanglement,
                                                                                                                                                                                        habitat
                                                                                                                                                                                        degradation,
                                                                                                                                                                                        pollution,
                                                                                                                                                                                        vessel
                                                                                                                                                                                        disturbance,
                                                                                                                                                                                        ocean noise,
                                                                                                                                                                                        climate change.
Fin whale.....................  Western North      Endangered.......  Depleted.........  Migratory........  Migratory........  Large............  Capital..........  Slow............  Vessel strikes,   No..............  No..............  Yes: Feeding      East of Montauk   Unk.............       11          2.05
                                 Atlantic.                            Strategic........                                                                                                 entanglement,                                         (n=3).            Point, Southern
                                                                                                                                                                                        habitat                                                                 Gulf of ME.
                                                                                                                                                                                        degradation,
                                                                                                                                                                                        pollution,
                                                                                                                                                                                        vessel
                                                                                                                                                                                        disturbance,
                                                                                                                                                                                        ocean noise,
                                                                                                                                                                                        climate change.
Humpback whale................  Gulf of Maine....  Not Listed.......  Not Depleted.....  Migratory........  Migratory........  Large............  Capital..........  Slow............  Vessel strikes,   UME (declared     No..............  Yes: Feeding      Gulf of ME        Increasing......       22         12.15
                                                                      Not Strategic....                                                                                                 entanglement,     2017, active).                      (n=1).            Child, Gulf of
                                                                                                                                                                                        habitat                                                                 ME Parent, Mid-
                                                                                                                                                                                        degradation,                                                            Atlantic Shelf,
                                                                                                                                                                                        pollution,                                                              NY Bight
                                                                                                                                                                                        vessel                                                                  Parent, South
                                                                                                                                                                                        disturbance,                                                            New England.
                                                                                                                                                                                        ocean noise,
                                                                                                                                                                                        climate change.
Minke whale...................  Canadian East      Not Listed.......  Not Depleted.....  Migratory........  Migratory........  Med/Large........  Capital..........  Slow............  Vessel strikes,   UME (declared     No..............  Yes: Feeding      Central Gulf of   Unk.............      170           9.4
                                 Coast.                               Not Strategic....                                                                                                 entanglement,     2017, active).                      (n=2).            ME/Parker Ridge/
                                                                                                                                                                                        habitat                                                                 Cashes Ledge,
                                                                                                                                                                                        degradation,                                                            Southwestern
                                                                                                                                                                                        pollution,                                                              Gulf of ME/
                                                                                                                                                                                        vessel                                                                  Georges Bank.
                                                                                                                                                                                        disturbance,
                                                                                                                                                                                        climate change,
                                                                                                                                                                                        disease.

[[Page 20027]]

 
Rice's whale..................  Northern Gulf of   Endangered.......  Depleted.........  Nomadic..........  Nomadic..........  Large............  Capital..........  Slow............  Vessel strike,    Small stock       Proposed          Yes: Small and    Expanded Range,   Decreasing......      0.1           0.5
                                 America.                             Strategic........                                                                                                 ocean noise,      size, DWH.        Critical          resident          Northeastern
                                                                                                                                                                                        energy                              Habitat:          population.       Gulf of America.
                                                                                                                                                                                        exploration and                     Proposed Gulf
                                                                                                                                                                                        development,                        of America 100-
                                                                                                                                                                                        oil spills,                         400 m isobath.
                                                                                                                                                                                        fisheries and
                                                                                                                                                                                        aquaculture
                                                                                                                                                                                        interaction,
                                                                                                                                                                                        ocean debris,
                                                                                                                                                                                        small
                                                                                                                                                                                        population
                                                                                                                                                                                        size, limited
                                                                                                                                                                                        distribution,
                                                                                                                                                                                        climate change.
Sei whale.....................  Nova Scotia......  Endangered.......  Depleted.........  Migratory........  Migratory........  Large............  Capital..........  Slow............  Vessel strike,    No..............  No..............  Yes: Feeding      Gulf of ME......  Unk.............      6.2           0.6
                                                                      Strategic........                                                                                                 entanglement,                                         (n=1).
                                                                                                                                                                                        ocean noise,
                                                                                                                                                                                        climate change.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Unk = Unknown; N/A = Not Applicable.


[[Page 20028]]

North Atlantic Right Whale (Western Stock)--
    North Atlantic right whales are listed as endangered under the ESA 
and as both a depleted and strategic stock under the MMPA. The current 
stock abundance estimate is 372 animals. As described in the Unusual 
Mortality Events section, a UME has been designated for NARW. North 
Atlantic right whales are migratory, though they have been detected 
across their range year-round. Detections in the mid-Atlantic are 
occurring more frequently (Engelhaupt et al. 2023), and Navy's AFTT 
Phase IV Density Technical Report predicts a NARW density in the Mid-
Atlantic Bight that is almost an order of magnitude higher from 2010-
2019 compared to 2003-2009, which is consistent with visual and 
acoustic surveys showing an increase in the use of the region (Davis et 
al., 2020; O'Brien et al., 2022).
    As described in the Description of Marine Mammals and Their Habitat 
in the Area of the Specified Activities section, the AFTT Study Area 
overlaps the NARW migratory corridor BIA, which represent areas and 
months within which a substantial portion of a species or population is 
known to migrate (LeBrecque et al. 2015). The Study Area also overlaps 
three seasonal feeding BIAs in the northeast Atlantic, a seasonal 
mating BIA in the central Gulf of Maine, and a seasonal calving BIA in 
the southeast Atlantic (LaBrecque et al. 2015), as well as important 
feeding habitat in southern New England, primarily along the western 
side of Nantucket Shoals (Estabrook et al., 2022; Kraus et al., 2016; 
Leiter et al., 2017; O'Brien et al., 2022, Quintano-Rizzo et al., 
2021). Additionally, the AFTT Study Area overlaps ESA-designated 
critical habitat for the NARW (Unit 1 and Unit 2) as described in the 
Critical Habitat section of this proposed rule.
    NARW are threatened due to a low population abundance, compromised 
body condition, high mortality rates, and low reproductive rates. They 
face several chronic anthropogenic and non-anthropogenic risk factors, 
including vessel strike, entanglement, and climate change, among 
others. Recent studies have reported individuals showing high stress 
levels (e.g., Corkeron et al., 2017) and poor health, which has further 
implications on reproductive success and calf survival (Christiansen et 
al., 2020; Stewart et al., 2021; Stewart et al., 2022; Pirotta et al. 
2024). Given these factors, the status of the NARW population is of 
heightened concern and, therefore, additional analysis is warranted.
    As shown in table 81, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment is 2 and 414, respectively. Given the current status of the 
NARW, the loss of even one individual could significantly impact the 
population. However, no mortality is anticipated or proposed for 
authorization, and nor is any non-auditory injury. The total take 
allowable across all 7 years of the rule is indicated in table 49.
    Regarding the potential takes associated with auditory impairment, 
as described in the Auditory Injury from Sonar Acoustic Sources and 
Explosives and Non-Auditory Injury from Explosives section above, any 
takes in the form of TTS are expected to be lower-level, of short 
duration (from minutes to, at most, several hours or less than a day), 
and mostly not in a frequency band that would be expected to interfere 
with NARW communication or other important low-frequency cues. Any 
associated lost opportunities or capabilities individuals might 
experience as a result of TTS would not be at a level or duration that 
would be expected to impact reproductive success or survival. For 
similar reasons, while auditory injury impacts last longer, the low 
anticipated levels of AUD INJ that could be reasonably expected to 
result from these activities are unlikely to have any effect on 
fitness.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 172 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. NARWs are 
large-bodied capital breeders with a slow pace of life, which would 
generally be less susceptible to impacts from shorter duration foraging 
disruptions.
    Further, as described in the Group and Species-Specific Analyses 
section above and the Proposed Mitigation Measures section, mitigation 
measures, several of which are designed specifically to reduce impacts 
to North Atlantic right whale, are expected to further reduce the 
potential severity of impacts through real-time operational measures 
that minimize higher level/longer duration exposures and time/area 
measures that reduce impacts in high value habitat. Specifically, this 
proposed rule includes several proposed geographic mitigation areas for 
NARW: Northeast North Atlantic Right Whale Mitigation Area, Gulf of 
Maine Mitigation Area, Jacksonville Operating Area North Atlantic Right 
Whale Mitigation Area, Southeast North Atlantic Right Whale Mitigation 
Area, Dynamic North Atlantic Right Whale Mitigation Areas, MTE Planning 
Awareness Mitigation Areas in the northeast and mid-Atlantic, and ship 
shock trial mitigation areas. The Northeast North Atlantic Right Whale 
Mitigation Area and Southeast North Atlantic Right Whale Mitigation 
Area in particular would reduce exposures in times and areas where 
impacts would be more likely to affect feeding and energetics (note 
that these mitigation areas are not quantitatively accounted for in the 
modeling, which means that the mitigation may prevent some of the takes 
predicted--though the analysis considers that they could all occur). 
Also, because of the proposed mitigation measures, the estimated takes 
would be less likely to occur in areas or at times where impacts would 
be likely to affect feeding and energetics or important cow/calf 
interactions that could lead to reduced reproductive success or 
survival, including those in areas known to be biologically important, 
and such impacts are not anticipated. Any impacts predicted in the east 
coast migratory corridor are less likely to impact individuals during 
feeding or breeding behaviors.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
number of takes by harassment as compared to the stock/species 
abundance (see table 81), it is likely that some portion of the 
individuals taken are taken repeatedly over a small number of days, 
particularly in the Northeast (70 percent of the takes predicted are in 
this region) during the winter and spring where and when a combined 58 
percent of takes of this stock would occur and animals are likely 
feeding. This is when North Atlantic right whales have a higher density 
at feeding grounds located near and south of Cape Cod, including areas 
overlapped by the Narragansett Bay OPAREA in the Northeast Range 
Complexes, and in the migratory corridor through the northeast region. 
However, given the variety of activity types that contribute to take 
across separate exercises conducted at different times and in different 
areas, the fact that

[[Page 20029]]

many result from transient activities conducted at sea, and fact that 
the number of takes as compared to the abundance is just above 100 
percent (112 percent), it is unlikely that takes would be in high 
enough numbers for any one individual or occur clumped across 
sequential days in a manner likely to impact foraging success and 
energetics, or that other behaviors such that reproduction or survival 
of any individuals is likely to be impacted.
    Given the magnitude and severity of the impacts discussed above to 
NARW (considering annual take maxima and the total across 7 years) and 
their habitat, and in consideration of the required mitigation measures 
and other information presented, the Action Proponents' activities are 
unlikely to result in impacts on the reproduction or survival of any 
individuals and, thereby, unlikely to affect annual rates of 
recruitment or survival. Further, we have considered the UME for NARW 
species described above, and even in consideration of the fact that 
some of the affected individuals may have compromised health, given the 
anticipated impacts of the activity, the proposed take is not expected 
to exacerbate the effects of the UME or otherwise impact the 
population. For these reasons, we have determined that the take by 
harassment anticipated and proposed for authorization would have a 
negligible impact on the Western stock of NARW.
Blue Whale (Western North Atlantic Stock)--
    Blue whales are listed as endangered under the ESA and as both 
depleted and strategic under the MMPA. The stock abundance is currently 
unknown, though NMFS' SAR reports an Nmin (minimum 
abundance) of 402. The stock's primary range is outside of the AFTT 
Study Area. There are no UMEs or other factors that cause particular 
concern for this stock, and there are no known biologically important 
areas for blue whales in the AFTT Study Area. They are frequently 
located in continental shelf waters near eastern Canada but have also 
been sighted off the coast of Florida and along the mid-Atlantic ridge 
(likely the southern portion of their feeding range). Blue whales face 
several chronic anthropogenic and non-anthropogenic risk factors, 
including vessel strike, entanglement, and climate change, among 
others.
    As shown in table 81, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment is 1 and 71, respectively. No mortality is anticipated or 
proposed for authorization, and nor is any non-auditory injury. The 
total take allowable across all 7 years of the rule is indicated in 
table 49.
    Regarding the potential takes associated with auditory impairment, 
as described in the Auditory Injury from Sonar Acoustic Sources and 
Explosives and Non-Auditory Injury from Explosives section above, any 
takes in the form of TTS are expected to be lower-level, of short 
duration, and mostly not in a frequency band that would be expected to 
interfere with blue whale communication or other important low-
frequency cues. Any associated lost opportunities or capabilities 
individuals might experience as a result of TTS would not be at a level 
or duration that would be expected to impact reproductive success or 
survival. For similar reasons, while auditory injury impacts last 
longer, the low anticipated levels of AUD INJ that could be reasonably 
expected to result from these activities are unlikely to have any 
effect on fitness.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 172 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Blue whales are 
large-bodied capital breeders with a slow pace of life, and are 
therefore generally less susceptible to impacts from shorter duration 
foraging disruptions. Further, as described in the Group and Species-
Specific Analyses section above and the Proposed Mitigation Measures 
section, mitigation measures are expected to further reduce the 
potential severity of impacts through real-time operational measures 
that minimize higher level/longer duration exposures and time/area 
measures that reduce impacts in high value habitat.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
lower number of takes by harassment as compared to the stock/species 
abundance (see table 81), their migratory movement pattern, and the 
absence of take concentrated in areas in which animals are known to 
congregate, it is unlikely that any individual blue whales would be 
taken on more than a small number of days within a year and, therefore, 
the anticipated behavioral disturbance is not expected to affect 
reproduction or survival.
    Given the magnitude and severity of the impacts discussed above to 
blue whales (considering annual take maxima and the total across 7 
years) and their habitat, and in consideration of the required 
mitigation measures and other information presented, the Action 
Proponents' activities are not expected to result in impacts on the 
reproduction or survival of any individuals, much less affect annual 
rates of recruitment or survival. For these reasons, we have determined 
that the take by harassment anticipated and proposed for authorization 
would have a negligible impact on the Western North Atlantic stock of 
blue whales.
Bryde's Whale (Primary)--
    This population of Bryde's whales spans the mid- and southern 
Atlantic. They have not been designated as a stock under the MMPA, are 
not ESA-listed, and there is no current reported population trend. 
There are no UMEs or other factors that cause particular concern for 
this stock and no known biologically important areas for Bryde's whale 
in the AFTT Study Area. Most Bryde's whales congregate in tropical 
waters south of the AFTT Study Area, and only occasionally travel as 
far north as Virginia. Bryde's whales generally face several chronic 
anthropogenic and non-anthropogenic risk factors, including vessel 
strike, entanglement, and climate change, among others.
    As shown in table 81, the maximum annual allowable instances of 
take under this proposed rule by Level B harassment is 11. No mortality 
is anticipated or proposed for authorization, and nor is any auditory 
or non-auditory injury (Level A harassment). The total take allowable 
across all 7 years of the rule is indicated in table 49.
    Regarding the potential takes associated with TTS, as described in 
the Temporary Threshold Shift section above, any takes in the form of 
TTS are expected to be lower-level, of short duration, and mostly not 
in a frequency band that would be expected to interfere with Bryde's 
whale communication or other important low-frequency cues. Any 
associated lost opportunities or capabilities individuals might 
experience as a result of TTS would not be at a level or duration that 
would be expected to impact reproductive success or survival.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the

[[Page 20030]]

majority of the predicted exposures are expected to be below 172 dB SPL 
and last from a few minutes to a few hours, at most, with associated 
responses most likely in the form of moving away from the source, 
foraging interruptions, vocalization changes, or disruption of other 
social behaviors, lasting from a few minutes to several hours. Bryde's 
whales are large-bodied capital breeders with a slow pace of life, and 
are therefore generally less susceptible to impacts from shorter 
duration foraging disruptions.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
low number of takes by harassment (see table 81), their migratory 
movement pattern, and the absence of take concentrated in areas in 
which animals are known to congregate, it is unlikely that any 
individual Bryde's whales would be taken on more than a small number of 
days within a year and, therefore, the anticipated behavioral 
disturbance is not expected to affect reproduction or survival.
    Given the magnitude and severity of the impacts discussed above to 
this population of Bryde's whales (considering annual take maxima and 
the total across 7 years) and their habitat, and in consideration of 
the required mitigation measures and other information presented, the 
Action Proponents' activities are not expected to result in impacts on 
the reproduction or survival of any individuals, much less affect 
annual rates of recruitment or survival. For these reasons, we have 
determined that the take by harassment anticipated and proposed for 
authorization would have a negligible impact on Bryde's whales.
Fin Whale (Western North Atlantic Stock)--
    Fin whales are listed as endangered under the ESA throughout the 
species' range and as both depleted and strategic under the MMPA. The 
Western North Atlantic stock abundance is 6,802 animals. There are no 
UMEs or other factors that cause particular concern for this stock. As 
described in the Description of Marine Mammals and Their Habitat in the 
Area of the Specified Activities section, the AFTT Study Area overlaps 
three fin whale feeding BIAs: (1) June to October in the northern Gulf 
of Maine; (2) year-round in the southern Gulf of Maine, and (3) March 
to October east of Montauk Point (LeBrecque et al. 2015), and more 
recent data supports that these areas remain biologically important 
(King et al., 2021; Lomac-MacNair et al., 2022). There is no ESA-
designated critical habitat for fin whales in the AFTT Study Area. The 
Western North Atlantic stock of fin whales may be present year-round in 
the Atlantic with higher densities near the shelf break in the 
Northeast and mid-Atlantic. Densities near feeding areas on the shelf 
in the Northeast are higher in the summer. Fin whales face several 
chronic anthropogenic and non-anthropogenic risk factors, including 
vessel strike, entanglement, and climate change, among others.
    As shown in table 81, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment is 21 and 2,616, respectively. As indicated, the rule also 
allows for up to 2 takes by serious injury or mortality over the course 
of the 7-year rule, the impacts of which are discussed above in the 
Serious Injury and Mortality section. No non-auditory injury is 
anticipated or proposed for authorization. The total take allowable 
across all 7 years of the rule is indicated in table 49.
    Regarding the potential takes associated with auditory impairment, 
as described in the Auditory Injury from Sonar Acoustic Sources and 
Explosives and Non-Auditory Injury from Explosives section above, any 
takes in the form of TTS are expected to be lower-level, of short 
duration (even the longest recovering in less than a day), and mostly 
not in a frequency band that would be expected to interfere with fin 
whale communication or other important low-frequency cues. Any 
associated lost opportunities or capabilities individuals might 
experience as a result of TTS would not be at a level or duration that 
would be expected to impact reproductive success or survival. For 
similar reasons, while auditory injury impacts last longer, the low 
anticipated levels of AUD INJ that could be reasonably expected to 
result from these activities are unlikely to have any effect on 
fitness.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 172 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Of the takes by 
Level B harassment, 5 would occur east of Montauk Point between March 
and October, and 52 would occur in the southern Gulf of Maine, both 
areas known to be biologically important for fin whale foraging. None 
of the takes by Level A harassment would occur in areas known to be 
biologically important. However, given that fin whales are large-bodied 
capital breeders with a slow pace of life, and are therefore generally 
less susceptible to impacts from shorter duration foraging disruptions, 
as well as the small number of takes anticipated to occur in the BIA, 
we do not anticipate that takes in this BIA would occur to any 
individual fin whale on more than a small number of days within a year, 
as described further below. Further, as described in the Group and 
Species-Specific Analyses section above and the Proposed Mitigation 
Measures section, mitigation measures are expected to further reduce 
the potential severity of impacts through real-time operational 
measures that minimize higher level/longer duration exposures and time/
area measures that reduce impacts in high value habitat.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
number of takes by harassment as compared to the stock/species 
abundance (see table 81), it is likely that some portion of the 
individuals taken are taken repeatedly over a small number of days. 
However, given the variety of activity types that contribute to take 
across separate exercises conducted at different times and in different 
areas, and the fact that many result from transient activities 
conducted at sea, it is unlikely that repeated takes would occur either 
in numbers or clumped across sequential days in a manner likely to 
impact foraging success and energetics or other behaviors such that 
reproduction or survival of any individuals is are likely to be 
impacted. Further, this stock is migratory, and the takes are not 
concentrated within a specific season.
    As analyzed and described in the Mortality section above, given the 
status of the stock and in consideration of other ongoing human-caused 
mortality, the M/SI proposed for authorization for the Western North 
Atlantic stock of fin whales (2 over the course of the 7-year rule, or 
0.29 annually) would not, alone, be expected to adversely affect the 
stock through rates of recruitment or survival. Given the magnitude and 
severity of the take by harassment discussed above and any anticipated 
habitat impacts, and in consideration of the required mitigation

[[Page 20031]]

measures and other information presented, the take by harassment 
proposed for authorization is unlikely to result in impacts on the 
reproduction or survival of any individuals and, thereby, unlikely to 
affect annual rates of recruitment or survival either alone or in 
combination with the M/SI proposed for authorization. For these 
reasons, we have determined that the take anticipated and proposed for 
authorization would have a negligible impact on the Western North 
Atlantic stock of fin whales.
Humpback Whale (Gulf of Maine Stock)--
    The West Indies DPS of humpback whales is not listed as threatened 
or endangered under the ESA, and the Gulf of Maine stock, which 
includes individuals from the West Indies DPS, is not considered 
depleted or strategic under the MMPA. The stock abundance is 1,396 
animals. As described in the Description of Marine Mammals and Their 
Habitat in the Area of the Specified Activities section, humpback 
whales along the Atlantic Coast have been experiencing an active UME as 
elevated humpback whale mortalities have occurred along the Atlantic 
coast from Maine through Florida since January 2016. Of the cases 
examined, approximately 40 percent had evidence of human interaction 
(vessel strike or entanglement). As also described in the Description 
of Marine Mammals and Their Habitat in the Area of the Specified 
Activities section, the AFTT Study Area overlaps a humpback whale 
feeding BIA (LeBrecque et al. 2015). This BIA is further supported by 
more recent information that suggests that the Gulf of Maine, Mid-
Atlantic Shelf, New York Bight, and south New England are all important 
for humpback whale feeding (Brown et al., 2019; Hayes et al., 2019; 
Aschettino et al., 2020; Davis et al., 2020; Zeh et al., 2020; King et 
al., 2021; Pershing et al., 2021; Stepanuk et al., 2021; Zoidis et al., 
2021; Lomac-MacNair et al., 2022; Smith et al., 2022). There is no ESA-
designated critical habitat for the Gulf of Maine stock of humpback 
whales given that the associated DPS is not ESA-listed. The Gulf of 
Maine stock of humpback whales have particularly strong site fidelity 
in the Gulf of Maine feeding grounds March to December and in the 
Caribbean calving grounds from December to May. Humpback whales, 
however, may occur in the AFTT Study Area, particularly in the mid-
Atlantic and Northeast, year-round. They occur near the Chesapeake Bay 
mouth except in the summer. Humpback whales face several chronic 
anthropogenic and non-anthropogenic risk factors, including vessel 
strike, entanglement, and climate change, among others.
    As shown in table 81, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment is 12 and 844, respectively. As indicated, the rule also 
allows for up to 4 takes by serious injury or mortality over the course 
of the 7-year rule, the impacts of which are discussed above in the 
Serious Injury and Mortality section. No non-auditory injury is 
anticipated or proposed for authorization. The total take allowable 
across all 7 years of the rule is indicated in table 49.
    Regarding the potential takes associated with auditory impairment, 
as described in the Auditory Injury from Sonar Acoustic Sources and 
Explosives and Non-Auditory Injury from Explosives section above, any 
takes in the form of TTS are expected to be lower-level, of short 
duration (even the longest recovering in several hours or less than a 
day), and mostly not in a frequency band that would be expected to 
interfere with humpback whale communication or other important low-
frequency cues. Any associated lost opportunities or capabilities 
individuals might experience as a result of TTS would not be at a level 
or duration that would be expected to impact reproductive success or 
survival. For similar reasons, while auditory injury impacts last 
longer, the low anticipated levels of AUD INJ that could be reasonably 
expected to result from these activities are unlikely to have any 
effect on fitness.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 172 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Humpback whales 
are large-bodied capital breeders with a slow pace of life, and are 
therefore generally less susceptible to impacts from shorter duration 
foraging disruptions. Further, as described in the Group and Species-
Specific Analyses section above and the Proposed Mitigation Measures 
section, mitigation measures are expected to further reduce the 
potential severity of impacts through real-time operational measures 
that minimize higher level/longer duration exposures and time/area 
measures that reduce impacts in high value habitat.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
number of takes by harassment as compared to the stock/species 
abundance (see table 81) and the fact that a portion of the takes occur 
in BIAs, it is likely that some portion of the individuals taken are 
taken repeatedly over a small number of days. However, given the 
migratory nature of the stock, the variety of activity types that 
contribute to take across separate exercises conducted at different 
times and in different areas (i.e., not concentrated within a specific 
region and season), and the fact that many result from transient 
activities conducted at sea, it is unlikely that repeated takes would 
occur either in numbers or clumped across sequential days in a manner 
likely to impact foraging success and energetics or other behaviors 
such that reproduction or survival of any individuals likely to be 
impacted. Further, as noted above, humpback whales are large-bodied 
capital breeders with a slow pace of life, and are therefore generally 
less susceptible to impacts from shorter duration foraging disruptions. 
As analyzed and described in the Mortality section above, given the 
status of the stock and in consideration of other ongoing human-caused 
mortality, the M/SI proposed for authorization for Gulf of Maine 
humpback whales (4 over the course of the 7-year rule, or 0.57 
annually) would not, alone, be expected to adversely affect the stock 
through rates of recruitment or survival. Given the magnitude and 
severity of the take by harassment discussed above and any anticipated 
habitat impacts, and in consideration of the required mitigation 
measures and other information presented, the take by harassment 
proposed for authorization is unlikely to result in impacts on the 
reproduction or survival of any individuals and, thereby, unlikely to 
affect annual rates of recruitment or survival either alone or in 
combination with the M/SI proposed for authorization. Last, we have 
both considered the effects of the UME on this stock in our analysis 
and findings regarding the impact of the activity on the stock, and, 
also, determined that we do not expect the proposed take to exacerbate 
the effects of the UME or otherwise impact the population. For these 
reasons, we have determined that the take anticipated and proposed for 
authorization would have a negligible

[[Page 20032]]

impact on the Gulf of Maine stock of humpback whales.
Minke Whale (Canadian East Coast Stock)--
    Minke whales are not listed as threatened or endangered under the 
ESA and are not considered depleted or strategic under the MMPA. The 
stock abundance is 21,968 animals (Hayes et al., 2024). The stock's 
range extends beyond the AFTT Study Area. There is an ongoing UME for 
minke whales along the Atlantic Coast from Maine through South 
Carolina, with the highest number of deaths in Massachusetts, Maine, 
and New York. Preliminary findings in several of the whales have shown 
evidence of human interactions or infectious diseases. However, we note 
that the stock abundance is greater than 21,000 and the take proposed 
for authorization is not expected to exacerbate the UME in any way. As 
described in the Description of Marine Mammals and Their Habitat in the 
Area of the Specified Activities section, the AFTT Study Area overlaps 
two minke whale feeding BIAs (Labrecque et al., 2015; CeTAP, 1982; 
Murphy, 1995). There is no ESA-designated critical habitat for minke 
whales, as the species is not ESA-listed. Minke whales face several 
chronic anthropogenic and non-anthropogenic risk factors, including 
vessel strike, entanglement, and climate change, among others.
    As shown in table 81, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment is 56 and 4,643, respectively. As indicated, the rule also 
allows for up to 2 takes by serious injury or mortality over the course 
of the 7-year rule, the impacts of which are discussed above in the 
Serious Injury and Mortality section. The total take allowable across 
all 7 years of the rule is indicated in table 49.
    Regarding the potential takes associated with auditory impairment, 
as described in the Auditory Injury from Sonar Acoustic Sources and 
Explosives and Non-Auditory Injury from Explosives section above, any 
takes in the form of TTS are expected to be lower-level, of short 
duration, and mostly not in a frequency band that would be expected to 
interfere with minke whale communication or other important low-
frequency cues. Any associated lost opportunities or capabilities 
individuals might experience as a result of TTS would not be at a level 
or duration that would be expected to impact reproductive success or 
survival. For similar reasons, while auditory injury impacts last 
longer, the low anticipated levels of AUD INJ that could be reasonably 
expected to result from these activities are unlikely to have any 
effect on fitness.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 172 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Minke whales 
are medium-to-large-bodied capital breeders with a slow pace of life, 
and are therefore generally less susceptible to impacts from shorter 
duration foraging disruptions. Further, as described in the Group and 
Species-Specific Analyses section above and the Proposed Mitigation 
Measures section, mitigation measures are expected to further reduce 
the potential severity of impacts through real-time operational 
measures that minimize higher level/longer duration exposures and time/
area measures that reduce impacts in high value habitat.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
lower number of takes by harassment as compared to the stock/species 
abundance (see table 81), their migratory movement pattern, and the 
absence of take concentrated in areas in which animals are known to 
congregate, it is unlikely that any individual minke whales would be 
taken on more than a small number of days within a year and, therefore, 
the anticipated behavioral disturbance is not expected to affect 
reproduction or survival.
    As analyzed and described in the Mortality section above, given the 
status of the stock and in consideration of other ongoing human-caused 
mortality, the M/SI proposed for authorization for Canadian East Coast 
minke whales (2 over the course of the 7-year rule, or 0.29 annually) 
would not, alone, be expected to adversely affect the stock through 
rates of recruitment or survival. Given the magnitude and severity of 
the take by harassment discussed above and any anticipated habitat 
impacts, and in consideration of the required mitigation measures and 
other information presented, the take by harassment proposed for 
authorization is unlikely to result in impacts on the reproduction or 
survival of any individuals and, thereby, unlikely to affect annual 
rates of recruitment or survival either alone or in combination with 
the M/SI proposed for authorization. Last, we have both considered the 
effects of the UME on this stock in our analysis and findings regarding 
the impact of the activity on the stock, and, also, determined that we 
do not expect the proposed take to exacerbate the effects of the UME or 
otherwise impact the population. For these reasons, we have determined 
that the take anticipated and proposed for authorization would have a 
negligible impact on the Canadian East Coast stock of minke whales.
Rice's Whale (Northern Gulf of America Stock)--
    Rice's whales are listed as endangered under the ESA and as both 
depleted and strategic under the MMPA. The stock abundance is 51 
animals (Hayes et al., 2024). The AFTT Study Area overlaps the Rice's 
whale small and resident population BIA (LaBrecque et al. 2015, further 
supported by more recent information (e.g., Rosel et al. 2021, Garrison 
et al. 2024)), as well as proposed ESA-designated critical habitat (88 
FR 47453, July 24, 2023), as described in the Description of Marine 
Mammals in the Area of Specified Activities section. Rice's whales face 
several chronic anthropogenic and non-anthropogenic risk factors, 
including vessel strike, energy exploration and development, climate 
change, and a limited population size and distribution, among others. 
Although this stock is not experiencing a UME, given the stock's 
status, low abundance and vulnerability, constricted range, and 
lingering effects of exposure to oil from the DWH oil spill (which 
include adverse health effects on individuals, as well as population 
effects), additional analysis is warranted.
    Although there is new evidence of Rice's whale occurrence in the 
central and western Gulf of America from passive acoustic detections 
(Soldevilla et al., 2022; 2024), the highest densities of Rice's whales 
remain confined to the northeastern Gulf of America core habitat, where 
their occurrence would overlap activities conducted in the offshore 
portions of the Naval Surface Warfare Center, Panama City Division 
Testing Area. The number of individuals that occur in the central and 
western Gulf of America and nature of their use of this area is poorly 
understood. Soldevilla et al. (2022) suggest that more than one 
individual was present on at least one occasion, as overlapping calls 
of different call subtypes were recorded in that instance, but also 
state that call detection rates suggest that either multiple 
individuals

[[Page 20033]]

are typically calling or that individual whales are producing calls at 
higher rates in the central/western Gulf of America. Soldevilla et al. 
(2024) provide further evidence that Rice's whale habitat encompasses 
all 100-400 m depth waters encircling the entire Gulf of America 
(including Mexican waters), but they also note that further research is 
needed to understand the density of whales in these areas, seasonal 
changes in whale density, and other aspects of habitat usage.
    As shown in table 81, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment is 3 and 303, respectively. No mortality is anticipated or 
proposed for authorization, and nor is any non-auditory injury. The 
total take allowable across all 7 years of the rule is indicated in 
table 49. Most impacts to Rice's whale are due to unmanned underwater 
vehicle testing, which may use sonars at a variety of frequencies for 
multiple hours most days of the year on the testing range. 44 percent 
of takes of this stock would occur during the winter when Rice's whale 
densities are predicted to be highest in the northeastern Gulf of 
America.
    Regarding the potential takes associated with auditory impairment, 
as described in the Auditory Injury from Sonar Acoustic Sources and 
Explosives and Non-Auditory Injury from Explosives section above, any 
takes in the form of TTS are expected to be lower-level, of short 
duration (from minutes to, at most, several hours or less than a day), 
and mostly not in a frequency band that would be expected to interfere 
with Rice's whale communication or other important low-frequency cues. 
Any associated lost opportunities or capabilities individuals might 
experience as a result of TTS would not be at a level or duration that 
would be expected to impact reproductive success or survival. For 
similar reasons, while auditory injury impacts last longer, the low 
anticipated levels of AUD INJ that could be reasonably expected to 
result from these activities are unlikely to have any effect on 
fitness.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 172 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Rice's whales 
are large-bodied capital breeders with a slow pace of life, which would 
generally be expected to be less susceptible to impacts from shorter-
term foraging disruption. Further, as described in the Group and 
Species-Specific Analyses section above and the Proposed Mitigation 
Measures section, mitigation measures are expected to further reduce 
the potential severity of impacts through real-time operational 
measures that minimize higher level/longer duration exposures and time/
area measures that reduce impacts in high value habitat. In particular, 
this proposed rulemaking includes a Rice's Whale Mitigation Area that 
overlaps the Rice's whale small and resident population area identified 
by NMFS in its 2016 status review (Rosel et al., 2016). This area 
encompasses the area where Rice's whales are most likely to occur as 
well as most of the eastern portion of proposed critical habitat. 
Within this area, the Action Proponents must not use more than 200 
hours of surface ship hull-mounted mid-frequency active sonar annually 
and must not detonate in-water explosives (including underwater 
explosives and explosives deployed against surface targets) except 
during mine warfare activities. Additionally, the Ship Shock Trial 
Mitigation Area would ensure that the northern Gulf of America ship 
shock trial box is situated outside of the Rice's whale core 
distribution area. These restrictions would reduce the severity of 
impacts to Rice's whales by reducing their exposure to levels of sound 
from sonar or explosives that would have the potential to cause injury, 
or mortality, thereby reducing the likelihood of those effects and, 
further, minimizing the severity of behavioral disturbance.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
number of takes by harassment as compared to the stock/species 
abundance (see table 81), it is likely that some portion of the 
individuals taken are taken repeatedly over a moderate number of days. 
However, unlike most large whales, Rice's whales are not migratory but 
are nomadic, so the risk of repeated impacts on individuals is likely 
similar within the population as animals move throughout their range. 
Further, given the variety of activity types that contribute to take 
across separate exercises conducted at different times and in different 
areas, and the fact that many result from transient activities 
conducted at sea, it is unlikely that takes would occur either in 
numbers or clumped across sequential days in a manner likely to impact 
foraging success and energetics or other behaviors such that 
reproduction or survival are likely to be impacted. While Rice's whale 
core habitat is in the northeastern portion of the Gulf of America 
which has been identified as biologically important (LaBrecque et al. 
2015), and a majority of takes would occur in that area, additional 
important Rice's whale habitat occurs between the 100 m and 400 m (328 
ft and 1,312 ft) isobath in the Gulf of America (Soldevilla et al., 
2024; 88 FR 47453, July 24, 2023).
    Given the magnitude and severity of the impacts discussed above to 
Rice's whale (considering annual take maxima and the total across 7 
years) and their habitat, and in consideration of the required 
mitigation measures and other information presented, the Action 
Proponents' activities are unlikely to result in impacts on the 
reproduction or survival of any individuals and, thereby, unlikely to 
affect annual rates of recruitment or survival. Last, we are aware that 
Rice's whales have experienced lower rates of reproduction and survival 
since the DWH oil spill, however, those effects are reflected in the 
SARs and other data considered in these analyses and do not change our 
findings. For these reasons, we have determined that the take by 
harassment anticipated and proposed for authorization would have a 
negligible impact on Rice's whale.
Sei Whale (Nova Scotia Stock)--
    Sei whales are listed as endangered under the ESA throughout its 
range and are considered depleted and strategic under the MMPA. The 
Nova Scotia stock abundance is 6,292 animals. There are no UMEs or 
other factors that cause particular concern for this stock. As 
described in the Description of Marine Mammals and Their Habitat in the 
Area of the Specified Activities section, the AFTT Study Area overlaps 
a sei whale feeding BIA. There is no ESA-designated critical habitat 
for sei whales in the AFTT Study Area. The highest sei whale abundance 
in U.S. waters occurs during spring, with sightings concentrated along 
the eastern margin of Georges Bank, into the Northeast Channel area, 
south of Nantucket, and along the southwestern edge of Georges Bank 
(CETAP 1982; Hayes et al. 2024; Kraus et al. 2016; Roberts et al. 2016; 
Palka et al. 2017; Cholewiak et al. 2018). Sei whales face several 
chronic anthropogenic and non-anthropogenic risk factors, including 
vessel strike,

[[Page 20034]]

entanglement, and climate change, among others.
    As shown in table 81, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment is 7 and 747, respectively. As indicated, the rule also 
allows for up to 2 takes by serious injury or mortality over the course 
of the 7-year rule, the impacts of which are discussed above in the 
Serious Injury and Mortality section. The total take allowable across 
all 7 years of the rule is indicated in table 49.
    Regarding the potential takes associated with auditory impairment, 
as described in the Auditory Injury from Sonar Acoustic Sources and 
Explosives and Non-Auditory Injury from Explosives section above, any 
takes in the form of TTS are expected to be lower-level, of short 
duration, and mostly not in a frequency band that would be expected to 
interfere with sei whale communication or other important low-frequency 
cues. Any associated lost opportunities or capabilities individuals 
might experience as a result of TTS would not be at a level or duration 
that would be expected to impact reproductive success or survival. For 
similar reasons, while auditory injury impacts last longer, the low 
anticipated levels of AUD INJ that could be reasonably expected to 
result from these activities are unlikely to have any effect on 
fitness.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 172 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Sei whales are 
large-bodied capital breeders with a slow pace of life, and are 
therefore generally less susceptible to impacts from shorter duration 
foraging disruptions. Further, as described in the Group and Species-
Specific Analyses section above and the Proposed Mitigation Measures 
section, mitigation measures are expected to further reduce the 
potential severity of impacts through real-time operational measures 
that minimize higher level/longer duration exposures and time/area 
measures that reduce impacts in high value habitat.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
lower number of takes by harassment as compared to the stock/species 
abundance (see table 81) and their migratory movement pattern, it is 
unlikely that any individual sei whales would be taken on more than a 
small number of days within a year and, therefore, the anticipated 
behavioral disturbance is not expected to affect reproduction or 
survival.
    As analyzed and described in the Mortality section above, given the 
status of the stock and in consideration of other ongoing human-caused 
mortality, the M/SI proposed for authorization for the Nova Scotia 
stock of sei whales (2 over the course of the 7-year rule, or 0.29 
annually) would not, alone, be expected to adversely affect the stock 
through rates of recruitment or survival. Given the magnitude and 
severity of the take by harassment discussed above and any anticipated 
habitat impacts, and in consideration of the required mitigation 
measures and other information presented, the take by harassment 
proposed for authorization is unlikely to result in impacts on the 
reproduction or survival of any individuals and, thereby, unlikely to 
affect annual rates of recruitment or survival either alone or in 
combination with the M/SI proposed for authorization. For these 
reasons, we have determined that the take anticipated and proposed for 
authorization would have a negligible impact on the Nova Scotia stock 
of sei whales.
Odontocetes
    This section builds on the broader discussion above and brings 
together the discussion of the different types and amounts of take that 
different stocks will incur, the applicable mitigation for each stock, 
and the status and life history of the stocks to support the negligible 
impact determinations for each stock. We have already described above 
why we believe the incremental addition of the small number of low-
level auditory injury takes will not have any meaningful effect towards 
inhibiting reproduction or survival. We have also described above in 
this section the unlikelihood of any masking or habitat impacts having 
effects that would impact the reproduction or survival of any of the 
individual marine mammals affected by the Action Proponents' 
activities. Some odontocete stocks have predicted non-auditory injury 
from explosives, discussed further below. Regarding the severity of 
individual takes by Level B harassment by behavioral disturbance for 
odontocetes, the majority of these responses are anticipated to occur 
at received levels below below 178 dB for most odontocete species and 
below 154 dB for sensitive species (i.e., beaked whales and harbor 
porpoises, for which a lower behavioral disturbance threshold is 
applied), and last from a few minutes to a few hours, at most, with 
associated responses most likely in the form of moving away from the 
source, foraging interruptions, vocalization changes, or disruption of 
other social behaviors, lasting from a few minutes to several hours. 
Much of the discussion below focuses on the behavioral effects and the 
mitigation measures that reduce the probability or severity of effects 
in biologically important areas or other habitat. Because there are 
multiple stock-specific factors in relation to the status of the 
species, as well as mortality take for several stocks, at the end of 
the section we break out stock- or group-specific findings.
    In table 83 (sperm whales, dwarf sperm whales, and pygmy sperm 
whales), table 85 (beaked whales), table 87 (dolphins and small 
whales), table 89 (porpoises), and table 91 (pinnipeds), we indicate 
the total annual mortality, Level A harassment, and Level B harassment, 
and a number indicating the instances of total take as a percentage of 
abundance.
    In table 84 (sperm whales, dwarf sperm whales, and pygmy sperm 
whales), table 86 (beaked whales), table 88 (dolphins and small 
whales), table 90 (porpoises), and table 92 (pinnipeds), below, we 
indicate the status, life history traits, important habitats, and 
threats that inform our analysis of the potential impacts of the 
estimated take on the affected odontocete stocks.
Sperm Whales, Dwarf Sperm Whales, and Pygmy Sperm Whales--

[[Page 20035]]



Table 83--Annual Estimated Take by Level B harassment, Level A harassment, and Mortality and Related Information for Atlantic Stocks of Sperm Whale, Dwarf Sperm Whale, and Pygmy Sperm Whale in
                                                                                       the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                           Maximum
                                                                                          Maximum      Maximum                           annual take
                                                                NMFS stock     NMSDD       annual       annual     Maximum    Maximum        as       Season(s) with 40     Region(s) with 40
        Marine mammal species                   Stock            abundance   abundance    Level B      Level A      annual     annual    percentage    percent of take      percent of take or
                                                                                         harassment   harassment  mortality     take      of stock        or greater             greater
                                                                                                                                          abundance
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale..........................  Northern Gulf of              1,180     * 1,614          275            0       0.14        275            17                N/A  Gulf of America (60
                                        America.                                                                                                                          percent).
Dwarf sperm whales...................  Northern Gulf of                336       * 510          189           22          0        211            41                N/A  Gulf of America (96
                                        America \a\.                                                                                                                      percent).
Pygmy sperm whales...................  Northern Gulf of                336       * 510          175           22          0        197            39                N/A  Gulf of America (95
                                        America \a\.                                                                                                                      percent).
Sperm whale..........................  North Atlantic.........     * 5,895       4,242       12,590            7       0.29     12,597           214                N/A  Mid-Atlantic (80
                                                                                                                                                                          percent).
Dwarf sperm whale....................  Western North Atlantic      * 9,474       2,426        6,326          180          0      6,506            69                N/A  Mid-Atlantic (73
                                        \a\.                                                                                                                              percent).
Pygmy sperm whales...................  Western North Atlantic      * 9,474       2,426        6,294          176          0      6,470            68                N/A  Mid-Atlantic (72
                                        \a\.                                                                                                                              percent).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: N/A = Not Applicable. NMSDD abundances are averages only within the U.S. EEZ.
* Indicates which abundance estimate was used to calculate the maximum annual take as a percentage of abundance, either the NMFS SAR (Hayes et al., 2024) or the NMSDD (table 2.4-1 in appendix
  A of the application). Please refer to the following section for details on which abundance estimate was selected.
\a\ Because Kogia sima and K. breviceps are difficult to differentiate at sea, the reported abundance estimates for the Western North Atlantic stock are for both species of Kogia combined.


                                                                  Table 84--Life History Traits, Important Habitat, and Threats to Sperm Whale, Dwarf Sperm Whale, and Pygmy Sperm Whale in the AFTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                                                                                                                                        Annual
                                                                                                                          Reproductive     Pace of      Chronic risk      UME, oil    ESA- designated  BIAs (Labrecque   Other important                              mortality
     Marine  mammal species             Stock         ESA  status      MMPA  status      Movement ecology    Body size      strategy        life          factors       spill, other      critical       et al. 2015)        habitat        Population trend    PBR     serious
                                                                                                                                                                                          habitat                                                                       injury
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale....................  Northern Gulf of    Endangered...  Depleted..........  Resident-migratory  Large.....  Income.........  Slow......  Vessel strike,     ............  No.............  No.............  None identified..  Unk, but possibly       2         9.6
                                  America.                          Strategic.........                                                                entanglement,                                                                         stable.
                                                                                                                                                      ocean noise,
                                                                                                                                                      marine debris,
                                                                                                                                                      oil spills and
                                                                                                                                                      contaminants,
                                                                                                                                                      energy
                                                                                                                                                      exploration and
                                                                                                                                                      development,
                                                                                                                                                      climate change.
Dwarf sperm whales.............  Northern Gulf of    Not Listed...  Not Depleted......  Unknown...........  Small-Med.  Income.........  Fast......  Entanglement,      ............  No.............  No.............  None identified..  Unk..............     2.5          31
                                  America.                          Not Strategic.....                                                                vessel strike,
                                                                                                                                                      marine debris,
                                                                                                                                                      ocean noise,
                                                                                                                                                      energy
                                                                                                                                                      exploration and
                                                                                                                                                      development, oil
                                                                                                                                                      spills, disease,
                                                                                                                                                      climate change.
Pygmy sperm whales.............  Northern Gulf of    Not Listed...  Not Depleted......  Unknown...........  Small-Med.  Income.........  Fast......  Entanglement,      ............  No.............  No.............  None identified..  Unk..............     2.5          31
                                  America.                          Not Strategic.....                                                                vessel strike,
                                                                                                                                                      marine debris,
                                                                                                                                                      ocean noise,
                                                                                                                                                      energy
                                                                                                                                                      exploration and
                                                                                                                                                      development, oil
                                                                                                                                                      spills, disease,
                                                                                                                                                      climate change.
Sperm whale....................  North Atlantic....  Endangered...  Depleted..........  Nomadic...........  Large.....  Income.........  Slow......  Vessel strike,     No..........  No.............  No.............  None identified..  Unk..............    9.28         0.2
                                                                    Strategic.........                                                                entanglement,
                                                                                                                                                      ocean noise,
                                                                                                                                                      marine debris,
                                                                                                                                                      oil spills and
                                                                                                                                                      contaminants,
                                                                                                                                                      climate change.

[[Page 20036]]

 
Dwarf sperm whale..............  Western North       Not Listed...  Not Depleted......  Unknown...........  Small-Med.  Income.........  Fast......  Entanglement,      No..........  No.............  No.............  None identified..  Increasing.......      57         Unk
                                  Atlantic.                         Not Strategic.....                                                                vessel strike,
                                                                                                                                                      marine debris,
                                                                                                                                                      ocean noise,
                                                                                                                                                      hunting (Lesser
                                                                                                                                                      Antilles),
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Pygmy sperm whales.............  Western North       Not Listed...  Not Depleted......  Unknown...........  Small-Med.  Income.........  Fast......  Entanglement,      No..........  No.............  No.............  None identified..  Increasing.......      57         Unk
                                  Atlantic.                         Not Strategic.....                                                                vessel strike,
                                                                                                                                                      marine debris,
                                                                                                                                                      ocean noise,
                                                                                                                                                      hunting (Lesser
                                                                                                                                                      Antilles),
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Unk = Unknown.


[[Page 20037]]

Sperm Whale (North Atlantic Stock), Dwarf Sperm Whale (Western North 
Atlantic and Northern Gulf of America Stocks), Pygmy Sperm Whale 
(Western North Atlantic and Northern Gulf of America Stocks)
    Sperm whales are listed as endangered under the ESA and the North 
Atlantic stock is considered depleted and strategic under the MMPA. 
Neither dwarf sperm whale nor pygmy sperm whale is listed under the 
ESA, and none of the stocks are considered depleted or strategic. The 
stock abundances range from 510 (combined estimate for the Northern 
Gulf of America stocks of dwarf and pygmy sperm whales from Navy's 
NMSDD) to 5,895 for the North Atlantic stock of sperm whale. There are 
no UMEs or other factors that cause particular concern for the stocks 
in the Atlantic Ocean, and there are no known biologically important 
areas for these stocks in the AFTT Study Area. These stocks face 
several chronic anthropogenic and non-anthropogenic risk factors, 
including entanglement and climate change, among others.
    As shown in table 83, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment range from 7 (North Atlantic stock of sperm whale) to 180 
(Western North Atlantic stock of dwarf sperm whale) and 175 (Northern 
Gulf of America stock of pygmy sperm whale) to 12,590 (North Atlantic 
stock of sperm whale), respectively. As indicated, the rule also allows 
for up to 2 takes by serious injury or mortality of North Atlantic 
sperm whales over the course of the 7-year rule, the impacts of which 
are discussed above in the Serious Injury and Mortality section. The 
total take allowable for each stock across all 7 years of the rule is 
indicated in table 49.
    Regarding the potential takes associated with auditory impairment, 
as described in the Auditory Injury from Sonar Acoustic Sources and 
Explosives and Non-Auditory Injury from Explosives section above, any 
takes in the form of TTS are expected to be lower-level, of short 
duration (even the longest recovering in several hours or less than a 
day), and mostly not in a frequency band that would be expected to 
interfere with odontocete echolocation, overlap more than a relatively 
narrow portion of the vocalization range of any single species or 
stock, or preclude detection or interpretation of important low-
frequency cues. Any associated lost opportunities or capabilities 
individuals might experience as a result of TTS would not be at a level 
or duration that would be expected to impact reproductive success or 
survival. For similar reasons, while auditory injury impacts last 
longer, the low anticipated levels of AUD INJ that could be reasonably 
expected to result from these activities are unlikely to have any 
effect on fitness. The rule also allows for one take of North Atlantic 
sperm whale by non-auditory injury (table 50). As described above, 
given the small number of potential exposures and the anticipated 
effectiveness of the mitigation measures in minimizing the pressure 
levels to which any individuals are exposed, these injuries are 
unlikely to impact reproduction or survival.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 178 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Pygmy and dwarf 
sperm whales are small-medium bodied income breeders with a fast pace 
of life. They are generally more sensitive to missed foraging 
opportunities, especially during lactation, but would be quick to 
recover given their fast pace of life. Sperm whales are large-bodied 
income breeders with a slow pace of life, and are likely more resilient 
to missed foraging opportunities due to acoustic disturbance than 
smaller odontocetes. However, they may be more susceptible to impacts 
due to lost foraging opportunities during reproduction, especially if 
they occur during lactation (Farmer et al., 2018). Further, as 
described in the Group and Species-Specific Analyses section above and 
the Proposed Mitigation Measures section, mitigation measures are 
expected to further reduce the potential severity of impacts through 
real-time operational measures that minimize higher level/longer 
duration exposures and time/area measures that reduce impacts in high 
value habitat.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
number of takes by harassment as compared to the stock/species 
abundance (see table 83) and the fact that the majority of takes of the 
Northern Gulf of America stock of pygmy and dwarf sperm whale occur in 
the Gulf of America (95 and 96 percent, respectively), and the majority 
of takes of the North Atlantic stock of sperm whale and Western North 
Atlantic stock of pygmy and dwarf sperm whale occur in the mid-Atlantic 
(80, 72, and 73 percent, respectively) it is likely that some portion 
of the individuals taken are taken repeatedly over a small number of 
days. However, given the variety of activity types that contribute to 
take across separate exercises conducted at different times and in 
different areas, and the fact that many result from transient 
activities conducted at sea, it is unlikely that repeated takes would 
occur either in numbers or clumped across sequential days in a manner 
likely to impact foraging success and energetics or other behaviors 
such that reproduction or survival are likely to be impacted. Further, 
sperm whales are nomadic, and there are no known foraging areas or 
other areas within which animals from any of these stocks are known to 
congregate.
    As analyzed and described in the Mortality section above, given the 
status of the stock and in consideration of other ongoing human-caused 
mortality, the M/SI proposed for authorization for the North Atlantic 
stock of sperm whales (2 over the course of the 7-year rule, or 0.29 
annually) would not, alone, be expected to adversely affect the stock 
through rates of recruitment or survival. Given the magnitude and 
severity of the take by harassment for each stock discussed above and 
any anticipated habitat impacts, and in consideration of the required 
mitigation measures and other information presented, the take by 
harassment proposed for authorization is unlikely to result in impacts 
on the reproduction or survival of any individuals and, thereby, 
unlikely to affect annual rates of recruitment or survival of any of 
these stocks either alone or, for the North Atlantic stock of sperm 
whale, in combination with the M/SI proposed for authorization. Last, 
we are aware that some Northern Gulf of America stocks have experienced 
lower rates of reproduction and survival since the DWH oil spill, 
however, those effects are reflected in the SARs and other data 
considered in these analyses and do not change our findings. For these 
reasons, we have determined that the take by harassment anticipated and 
proposed for authorization would have a negligible impact on the North 
Atlantic stock of sperm whale, Northern Gulf of America stocks of dwarf 
and pygmy sperm whales, and Western

[[Page 20038]]

North Atlantic stocks of dwarf and pygmy sperm whales.
Sperm Whale (Northern Gulf of America stock)
    Sperm whales are listed as endangered under the ESA and the 
Northern Gulf of America stock is considered depleted and strategic 
under the MMPA. The Navy's NMSDD estimates the stock abundance as 1,614 
animals. Sperm whales aggregate at the mouth of the Mississippi River 
and along the continental slope in or near cyclonic cold-core eddies 
(counterclockwise water movements in the northern hemisphere with a 
cold center) or anticyclone eddies (clockwise water movements in the 
northern hemisphere) (Davis et al., 2007). Habitat models for sperm 
whale occurrence indicate a high probability of suitable habitat along 
the shelf break off the Mississippi delta, Desoto Canyon, and western 
Florida (Best et al., 2012; Weller et al., 2000), and this area may be 
important for feeding and reproduction (Baumgartner et al., 2001; 
Jochens et al., 2008; NMFS, 2010), although the seasonality of breeding 
in Northern Gulf of America stock of sperm whales is not known (Jochens 
et al., 2008). This stock faces several chronic anthropogenic and non-
anthropogenic risk factors, including vessel strike, entanglement, oil 
spills, and climate change, among others.
    As shown in table 83, the maximum annual allowable instances of 
take under this proposed rule by Level B harassment is 275. As 
indicated, the rule also allows for up to 1 takes by serious injury or 
mortality over the course of the 7-year rule, the impacts of which are 
discussed above in the Serious Injury and Mortality section. No Level A 
harassment (auditory or non-auditory injury) is proposed for 
authorization. The total take allowable across all 7 years of the rule 
is indicated in table 49.
    Regarding the potential takes associated with TTS, as described in 
the Temporary Threshold Shift section above, any takes in the form of 
TTS are expected to be lower-level, of short duration (even the longest 
recovering in several hours or less than a day), and mostly not in a 
frequency band that would be expected to interfere with sperm whale 
communication or other important low-frequency cues. Any associated 
lost opportunities or capabilities individuals might experience as a 
result of TTS would not be at a level or duration that would be 
expected to impact reproductive success or survival.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 178 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Sperm whales 
are large-bodied income breeders with a slow pace of life, and are 
likely more resilient to missed foraging opportunities due to acoustic 
disturbance than smaller odontocetes. However, they may be more 
susceptible to impacts due to lost foraging opportunities during 
reproduction, especially if they occur during lactation (Farmer et al., 
2018).
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
lower number of takes by harassment as compared to the stock/species 
abundance (see table 83), their migratory movement pattern, and the 
absence of take concentrated in areas in which animals are known to 
congregate, it is unlikely that any individual sperm whales would be 
taken on more than a small number of days within a year and, therefore, 
the anticipated behavioral disturbance is not expected to affect 
reproduction or survival.
    As analyzed and described in the Mortality section above, given the 
status of the stock and in consideration of other ongoing human-caused 
mortality, the M/SI proposed for authorization for the Northern Gulf of 
America stock of sperm whales (one over the course of the 7-year rule, 
or 0.14 annually) would not, alone, be expected to adversely affect the 
stock through rates of recruitment or survival. Given the magnitude and 
severity of the take by harassment discussed above and any anticipated 
habitat impacts, and in consideration of the required mitigation 
measures and other information presented, the take by harassment 
proposed for authorization is unlikely to result in impacts on the 
reproduction or survival of any individuals and, thereby, unlikely to 
affect annual rates of recruitment or survival either alone or in 
combination with the M/SI proposed for authorization. Last, we are 
aware that some Northern Gulf of America stocks have experienced lower 
rates of reproduction and survival since the DWH oil spill, however, 
those effects are reflected in the SARs and other data considered in 
these analyses and do not change our findings. For these reasons, we 
have determined that the take anticipated and proposed for 
authorization would have a negligible impact on the Northern Gulf of 
America stock of sperm whales.
Beaked Whales--
    This section builds on the broader odontocete discussion above 
(i.e., that information applies to beaked whales as well), and brings 
together the discussion of the different types and amounts of take that 
different beaked whale species and stocks will likely incur, any 
additional applicable mitigation, and the status of the species and 
stocks to support the negligible impact determinations for each species 
or stock.

          Table 85--Annual Estimated Take by Level B Harassment, Level A Harassment, and Mortality and Related Information for Atlantic Stocks of Beaked Whales in the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                               Maximum
                                                                                               Maximum      Maximum                          annual take   Season(s)
                                                                     NMFS stock     NMSDD       annual       annual     Maximum    Maximum        as        with 40    Region(s) with 40 percent
         Marine mammal species                      Stock             abundance   abundance    Level B      Level A      annual     annual    percentage   percent of     of take or  greater
                                                                                              harassment   harassment  mortality     take      of stock     take or
                                                                                                                                              abundance     greater
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Blainville's beaked whale..............  Northern Gulf of America..          98        * 99          126            0          0        126          127          N/A  Key West (64 percent).
Goose-beaked whale.....................  Northern Gulf of America..          18       * 368          460            0          0        460          125          N/A  Key West (62 percent).
Gervais' beaked whale..................  Northern Gulf of America..          20       * 386          125            0          0        125           32          N/A  Key West (65 percent).
Blainville's beaked whale..............  Western North Atlantic....     * 2,936       1,279       25,705            1          0     25,706          876          N/A  Mid-Atlantic (66
                                                                                                                                                                        percent).

[[Page 20039]]

 
Goose-beaked whale.....................  Western North Atlantic....       4,260     * 4,901      112,070            2          0    112,072        2,287          N/A  Mid-Atlantic (80
                                                                                                                                                                        percent).
Gervais' beaked whale..................  Western North Atlantic....     * 8,595         991       25,446            1          0     25,447          296          N/A  Mid-Atlantic (66
                                                                                                                                                                        percent).
Northern bottlenose whale..............  Western North Atlantic....       * Unk          82        1,651            1          0      1,652          Unk          N/A  Northeast (47 percent)
                                                                                                                                                                        Mid-Atlantic (52
                                                                                                                                                                        percent).
Sowerby's beaked whale.................  Western North Atlantic....         492     * 1,279       25,622            1          0     25,623        2,003          N/A  Mid-Atlantic (67
                                                                                                                                                                        percent).
True's beaked whale....................  Western North Atlantic....     * 4,480       1,279       25,582            0          0     25,582          571          N/A  Mid-Atlantic (68
                                                                                                                                                                        percent).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Unk = Unknown; N/A = Not Applicable. NMSDD abundances are averages only within the U.S. EEZ.
* Indicates which abundance estimate was used to calculate the maximum annual take as a percentage of abundance, either the NMFS SAR (Hayes et al., 2024) or the NMSDD (table 2.4-1 in appendix
  A of the application). Please refer to the following section for details on which abundance estimate was selected.


[[Page 20040]]


                                                                                      Table 86--Life History Traits, Important Habitat, and Threats to Beaked Whales in the AFTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                                                                                                                                        Annual
                                                                                                                 Body      Reproductive    Pace  of      Chronic risk      UME, oil    ESA- designated  BIAs (Labrecque   Other important                             mortality/
     Marine mammal species              Stock           ESA status         MMPA status      Movement ecology     size        strategy        life          factors       spill, other      critical       et al. 2015)        habitat        Population trend   PBR     serious
                                                                                                                                                                                           habitat                                                                      injury
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Blainville's beaked whale......  Northern Gulf of    Not Listed......  Not Depleted......  Nomadic-resident..  Med.....  Mixed..........  Med.......  Entanglement,      N/A.........  No.............  No.............  None identified..  Unk..............    0.7         5.2
                                  America.                             Not Strategic.....                                                              marine debris,
                                                                                                                                                       ocean noise,
                                                                                                                                                       energy
                                                                                                                                                       exploration and
                                                                                                                                                       development, oil
                                                                                                                                                       spills, climate
                                                                                                                                                       change.
Goose-beaked whale.............  Northern Gulf of    Not Listed......  Not Depleted......  Nomadic-resident..  Med.....  Mixed..........  Med.......  Ocean noise,       N/A.........  No.............  No.............  None identified..  Unk..............    0.1         5.2
                                  America.                             Not Strategic.....                                                              energy
                                                                                                                                                       exploration and
                                                                                                                                                       development, oil
                                                                                                                                                       spills, climate
                                                                                                                                                       change.
Gervais' beaked whale..........  Northern Gulf of    Not Listed......  Not Depleted......  Nomadic-resident..  Med.....  Mixed..........  Med.......  Entanglement,      N/A.........  No.............  No.............  None identified..  Unk..............    0.1         5.2
                                  America.                             Not Strategic.....                                                              ocean noise,
                                                                                                                                                       energy
                                                                                                                                                       exploration and
                                                                                                                                                       development, oil
                                                                                                                                                       spills, climate
                                                                                                                                                       change.
Blainville's beaked whale......  Western North       Not Listed......  Not Depleted......  Nomadic-resident..  Med.....  Mixed..........  Med.......  Entanglement,      N/A.........  No.............  No.............  None identified..  Unk..............     24         0.2
                                  Atlantic.                            Not Strategic.....                                                              marine debris,
                                                                                                                                                       ocean noise,
                                                                                                                                                       climate change.
Goose-beaked whale.............  Western North       Not Listed......  Not Depleted......  Nomadic-resident..  Med.....  Mixed..........  Med.......  Ocean noise,       N/A.........  No.............  No.............  Georges Bank and   Unk, possibly         38         0.2
                                  Atlantic.                            Not Strategic.....                                                              climate change.                                                    New England        increasing.
                                                                                                                                                                                                                          Seamounts,
                                                                                                                                                                                                                          Canyons off New
                                                                                                                                                                                                                          Jersey and
                                                                                                                                                                                                                          Delmarva, Cape
                                                                                                                                                                                                                          Hatteras,
                                                                                                                                                                                                                          Southeast U.S..
Gervais' beaked whale..........  Western North       Not Listed......  Not Depleted......  Nomadic-resident..  Med.....  Mixed..........  Med.......  Entanglement,      N/A.........  No.............  No.............  None identified..  Unk..............     70           0
                                  Atlantic.                            Not Strategic.....                                                              hunting, ocean
                                                                                                                                                       noise, climate
                                                                                                                                                       change.
Northern bottlenose whale......  Western North       Not Listed......  Not Depleted......  Nomadic-resident..  Large...  Mixed..........  Med.......  Ocean noise,       N/A.........  No.............  No.............  None identified..  Unk..............    Unk           0
                                  Atlantic.                            Not Strategic.....                                                              hunting, climate
                                                                                                                                                       change.
Sowerby's beaked whale.........  Western North       Not Listed......  Not Depleted......  Nomadic-resident..  Med.....  Mixed..........  Med.......  Ocean noise,       N/A.........  No.............  No.............  None identified..  Unk..............    3.4           0
                                  Atlantic.                            Not Strategic.....                                                              PCBs,
                                                                                                                                                       entanglement,
                                                                                                                                                       climate change.
True's beaked whale............  Western North       Not Listed......  Not Depleted......  Nomadic-resident..  Med.....  Mixed..........  Med.......  Ocean noise,       N/A.........  No.............  No.............  None identified..  Unk, possibly         34         0.2
                                  Atlantic.                            Not Strategic.....                                                              climate change.                                                                       increasing.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: N/A = Not Applicable; Und = Undetermined; Unk = Unknown.


[[Page 20041]]

Beaked Whales (Western North Atlantic Stocks)
    These stocks are not listed as endangered or threatened under the 
ESA, and they are not considered depleted or strategic under the MMPA. 
The stock abundance estimates generally range from 1,279 (Sowerby's 
beaked whale, NMSDD) to 8,595 (Gervais' beaked whale). The SAR states 
that the abundance of Western North Atlantic northern bottlenose whale 
is unknown, and the NMSDD estimates the stock abundance as 82 animals, 
but reports that the estimate is from within the EEZ and is lower than 
the overall population abundance given that the range of the stock 
exceeds the EEZ boundary. See the Density Technical Report (U.S. 
Department of the Navy, 2024) for additional information. There are no 
UMEs or other factors that cause particular concern for this stock, and 
there are no known biologically important areas for beaked whales in 
the AFTT Study Area, though of note, these stocks generally occur in 
higher densities year-round in deep waters over the Atlantic 
continental shelf margins. The Western North Atlantic stocks of goose-
beaked whales and Blainville's beaked whales generally congregate over 
continental shelf margins from Canada to North Carolina, with goose-
beaked whales reported as far south as the Caribbean and Blainville's 
beaked whales as far south as the Bahamas. The Western North Atlantic 
stock of Gervais' beaked whales generally congregate over continental 
shelf margins from New York to North Carolina. The Western North 
Atlantic stock of Sowerby's beaked whales is the most northerly 
distributed stock of deep-diving mesoplodonts, and they generally 
congregate over continental shelf margins from Labrador to 
Massachusetts. The Western North Atlantic stock of True's beaked whales 
generally congregate over continental shelf margins from Nova Scotia to 
Cape Hatteras, with northern occurrence likely relating to the Gulf 
Stream. The Western North Atlantic stock of Northern bottlenose whales 
is uncommon in U.S. waters and generally congregates in areas of high 
relief, including shelf breaks and submarine canyons from the Davis 
Strait to New England, although strandings have occurred as far south 
as North Carolina. Western North Atlantic beaked whales face several 
chronic anthropogenic and non-anthropogenic risk factors, including 
entanglement and climate change, among others.
    As shown in table 85, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment range from 0 to 2 and 1,651 to 112,070, respectively. No 
mortality is anticipated or proposed for authorization, and nor is any 
non-auditory injury. The total take allowable across all 7 years of the 
rule is indicated in table 49.
    Regarding the potential takes associated with auditory impairment 
(for True's beaked whale, TTS only), as described in the Auditory 
Injury from Sonar Acoustic Sources and Explosives and Non-Auditory 
Injury from Explosives section above, any takes in the form of TTS are 
expected to be lower-level, of short duration (from minutes to, at 
most, several hours or less than a day), and mostly not in a frequency 
band that would be expected to interfere with odontocete echolocation, 
overlap more than a relatively narrow portion of the vocalization range 
of any single species or stock, or preclude detection or interpretation 
of important low-frequency cues. Any associated lost opportunities or 
capabilities individuals might experience as a result of TTS would not 
be at a level or duration that would be expected to impact reproductive 
success or survival. For similar reasons, while auditory injury impacts 
last longer, the low anticipated levels of AUD INJ that could be 
reasonably expected to result from these activities (for all Western 
North Atlantic beaked whales except True's beaked whales) are unlikely 
to have any effect on fitness.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 154 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Beaked whales 
are medium-to-large-bodied odontocetes with a medium pace of life and 
likely moderately resilient to missed foraging opportunities due to 
acoustic disturbance. They are mixed breeders (i.e., behaviorally 
income breeders), and they demonstrate capital breeding strategies 
during gestation and lactation (Keen et al., 2021), so they may be more 
vulnerable to prolonged loss of foraging opportunities during 
gestation. Further, as described in the Group and Species-Specific 
Analyses section above and the Proposed Mitigation Measures section, 
mitigation measures are expected to further reduce the potential 
severity of impacts through real-time operational measures that 
minimize higher level/longer duration exposures and time/area measures 
that reduce impacts in high value habitat.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
number of takes by harassment as compared to the stock/species 
abundance (see table 85), it is likely that some portion of the 
individuals taken are taken repeatedly over a small (Western North 
Atlantic northern bottlenose whale and Gervais' beaked whale) to 
moderate (all other stocks) number of days, with the exception of 
Sowerby's beaked whales (discussed below). However, given the variety 
of activity types that contribute to take across separate exercises 
conducted at different times and in different areas, and the fact that 
many result from transient activities conducted at sea, it is unlikely 
that takes would occur clumped across sequential days in a manner 
likely to impact foraging success and energetics or other behaviors 
such that reproduction or survival are likely to be impacted. Further, 
while there are several known high-density areas for goose-beaked 
whales, around canyons, seamounts, and Cape Hatteras, which is common 
for multiple species, there are no known foraging areas or other areas 
within which animals are known to congregate for reproductive or other 
important behaviors, and nor are the takes concentrated within a 
specific region and season.
    Regarding the magnitude of repeated takes for the Sowerby's beaked 
whales, given the high number of takes by harassment as compared to the 
stock abundance, it is more likely that some number of individuals 
would experience a comparatively higher number of repeated takes over a 
potentially fair number of sequential days. Due to the higher number of 
repeated takes, it is more likely that a portion of the individuals 
taken by harassment (approximately 50 percent of which would be female) 
could be repeatedly interrupted during foraging in a manner and amount 
such that impacts to the energy budgets of a small number of females 
(from either losing feeding opportunities or expending considerable 
energy moving away from sound sources or finding alternative feeding 
options) could cause them to forego reproduction for a year (noting 
that beaked whale calving intervals may be about 2 years) (New et al., 
2013)).

[[Page 20042]]

Energetic impacts to males are generally meaningless to population 
rates unless they cause death, and it takes extreme energy deficits 
beyond what would ever be likely to result from these activities to 
cause the death of an adult marine mammal, male or female. While the 
population trend of this stock is not known, it is not considered 
depleted or strategic, and there are no known sources of human-caused 
mortality indicated in the SARs. Importantly, the increase in a calving 
interval by a year would have far less of an impact on a population 
rate than a mortality would and, accordingly, a small number of 
instances of foregone reproduction would not be expected to adversely 
affect this stock through effects on annual rates of recruitment or 
survival (noting also that no mortality is predicted or authorized for 
this stock). The population trend of the Western North Atlantic stock 
of goose-beaked whales is not known but possibly increasing, and, like 
the Sowerby's beaked whale stock, it is not considered depleted or 
strategic, and there are no known sources of human-caused mortality 
indicated in the SARs. Importantly, the increase in a calving interval 
by a year would have far less of an impact on a population rate than a 
mortality would and, accordingly, a limited number of instances of 
foregone reproduction would not be expected to adversely affect this 
stock through effects on annual rates of recruitment or survival 
(noting also that no mortality is predicted or authorized for this 
stock).
    Given the magnitude and severity of the take by harassment 
discussed above and any anticipated habitat impacts, and in 
consideration of the required mitigation measures and other information 
presented, the Action Proponents' activities are unlikely to result in 
impacts on the reproduction or survival of any individuals of the 
Western North Atlantic stocks of beaked whales (Blainville's beaked 
whale, goose-beaked whale, Gervais' beaked whale, northern bottlenose 
dolphin, and True's beaked whale), with the exception of Sowerby's 
beaked whales, and thereby unlikely to affect annual rates of 
recruitment or survival. For Sowerby's beaked whales, as described 
above, we do not anticipate the relatively small number of individuals 
that might be taken over repeated days within the year in a manner that 
results in a year of foregone reproduction to adversely affect either 
stock through effects on rates of recruitment or survival, given the 
statuses of these stocks. For these reasons, we have determined that 
the total take (considering annual maxima and across seven years) 
anticipated and proposed for authorization would have a negligible 
impact on all Western North Atlantic beaked whales.
Beaked Whales (Northern Gulf of America Stocks)
    These stocks are not listed as endangered or threatened under the 
ESA, and they are not considered depleted or strategic under the MMPA. 
The estimated abundances of these Blainville's beaked whale, goose-
beaked whale, and Gervais' beaked whale are 99, 368, and 386, 
respectively, as indicated in the Navy's NMSDD estimates. There are no 
known biologically important areas for beaked whales in the Gulf of 
America. These stocks all occur year-round in deep water areas in the 
Gulf of America and Key West. Beaked whales in the Gulf of America face 
several chronic anthropogenic and non-anthropogenic risk factors, 
including energy exploration and development, entanglement, and climate 
change, among others.
    As shown in table 85, the maximum annual allowable instances of 
take under this proposed rule by Level B harassment is 126, 460, and 
125 for Blainville's beaked whale, goose-beaked whale, and Gervais' 
beaked whale, respectively. No mortality is anticipated or proposed for 
authorization, and nor is any auditory or non-auditory injury (Level A 
harassment). The total take allowable across all 7 years of the rule is 
indicated in table 49.
    Regarding the potential takes associated with TTS, as described in 
the Temporary Threshold Shift section above, any takes in the form of 
TTS are expected to be lower-level, of short duration (from minutes to, 
at most, several hours or less than a day), and mostly not in a 
frequency band that would be expected to interfere with odontocete 
echolocation, overlap more than a relatively narrow portion of the 
vocalization range of any single species or stock, or preclude 
detection or interpretation of important low-frequency cues. Any 
associated lost opportunities or capabilities individuals might 
experience as a result of TTS would not be at a level or duration that 
would be expected to impact reproductive success or survival.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 154 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Beaked whales 
are medium-bodied odontocetes with a medium pace of life and likely 
moderately resilient to missed foraging opportunities due to acoustic 
disturbance. They are mixed breeders (i.e., behaviorally income 
breeders) and they demonstrate capital breeding strategies during 
gestation and lactation (Keen et al., 2021), so they may be more 
vulnerable to prolonged loss of foraging opportunities during 
gestation.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
number of takes by harassment as compared to the stock/species 
abundances (see table 85) and the fact that 60-65 percent of the takes 
occur around Key West, it is likely that some portion of the 
individuals taken are taken repeatedly over a small number of days. 
However, given the variety of activity types that contribute to take 
across separate exercises conducted at different times and in different 
areas, and the fact that many result from transient activities 
conducted at sea, it is unlikely that repeated takes would occur either 
in numbers or clumped across sequential days in a manner likely to 
impact foraging success and energetics or other behaviors such that 
reproduction or survival are likely to be impacted.
    Given the magnitude and severity of the impacts discussed above to 
Northern Gulf of America stocks of beaked whales (considering annual 
take maxima and the total across 7 years) and their habitat, and in 
consideration of the other information presented, the Action 
Proponents' activities are unlikely to result in impacts on the 
reproduction or survival of any individuals and, thereby, unlikely to 
affect annual rates of recruitment or survival. Last, we are aware that 
some Northern Gulf of America stocks of beaked whales have experienced 
lower rates of reproduction and survival since the DWH oil spill, 
however, those effects are reflected in the SARs and other data 
considered in these analyses and do not change our findings. For these 
reasons, we have determined that the take by harassment anticipated and 
proposed for authorization would have a negligible impact on the 
Northern Gulf of America stocks of beaked whales.

[[Page 20043]]

Dolphins and Small Whales--
    Of the 53 stocks of dolphins and small whales (Delphinidae) for 
which incidental take is proposed for authorization (see table 87), 
none are listed as endangered or threatened under the ESA. Only spinner 
dolphins are listed as depleted under the MMPA, however, about a third 
of the species are listed as strategic, including 14 stocks of 
bottlenose dolphins, Northern Gulf of America stocks of Clymene, 
striped, and spinner dolphins, and the Western Northern Atlantic stocks 
of spinner dolphins and short-finned pilot whales. As shown in table 87 
and table 88, these Delphinids vary in stock abundance, body size, and 
movement ecology from, for example, the small-bodied, nomadic/migratory 
Western North Atlantic white-beaked dolphins that range well beyond the 
U.S. EEZ and outside the AFTT Study Area and have a SAR abundance over 
500,000, to the medium-sized resident Bay stocks of bottlenose dolphins 
with abundances under 200, to the large-bodied nomadic Western North 
Atlantic killer whale, for which the abundance is unknown. While there 
are several small and resident populations of bottlenose dolphins, 
there are no other known biologically important areas (e.g., foraging, 
reproduction) for any of these Delphinid stocks. Delphinids face a 
number of chronic anthropogenic and non-anthropogenic risk factors 
including biotoxins, chemical contaminants, fishery interaction, 
habitat alteration, illegal feeding/harassment, ocean noise, oil spills 
and energy exploration, vessel strikes, disease, climate change, the 
impacts of which vary depending whether the stock is more coastal 
(e.g., biotoxins and some fishing interactions more seen in bottlenose 
dolphins), more or less deep-diving (e.g., entanglement more common in 
deep divers like pygmy killer whales and pilot whales), in the Gulf of 
America (e.g., lingering lower reproductive rates for some stocks 
affected by DWH oil spill impacts), and other behavioral differences 
(e.g., vessels strikes more concern for killer whales).

[[Page 20044]]



                      Table 87--Annual Estimated Take by Level B Harassment, Level A Harassment, and Mortality and Related Information for Dolphins in the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                              Maximum
                                                                                                                               annual                                           Greatest degree
                                                                              Maximum      Maximum     Maximum    Maximum    harassment  Season(s) with 40  Region(s) with 40    any individual
     Marine mammal species             Stock        NMFS stock     NMSDD       annual       annual      annual     annual        as       percent of take    percent of take     expected to be
                                                     abundance   abundance    Level B      Level A    mortality     take     percentage      or greater         or greater      taken repeatedly
                                                                             harassment   harassment                          of stock                                          across multiple
                                                                                                                             abundance                                                days
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Atlantic spotted dolphin.......  Northern Gulf of     * 21,506      11,476       12,804           20          0     12,824           60  N/A..............  Gulf of America    Zero to small
                                  America.                                                                                                                   (100 percent).     number of days.
Bottlenose dolphin.............  Gulf of America      * 16,407      13,382           80            0          0         80            0  N/A..............  Gulf of America    Zero to small
                                  Eastern Coastal.                                                                                                           (63 percent).      number of days.
Bottlenose dolphin.............  Gulf of America      * 11,543       7,031        7,146           17          0      7,163           62  N/A..............  Gulf of America    Zero to small
                                  Northern Coastal.                                                                                                          (100 percent).     number of days.
Bottlenose dolphin.............  Northern Gulf of        7,462    * 21,997        6,274            4          0      6,278           29  N/A..............  Gulf of America    Zero to small
                                  America Oceanic.                                                                                                           (70 percent).      number of days.
Bottlenose dolphin.............  Gulf of America        20,759    * 26,100        3,331            1          0      3,332           13  N/A..............  Gulf of America    Zero to small
                                  Western Coastal.                                                                                                           (100 percent).     number of days.
Bottlenose dolphin.............  Mississippi             1,265     * 1,057        1,758            1          0      1,759          166  N/A..............  Gulf of America    Small number of
                                  Sound, Lake                                                                                                                (100 percent).     days.
                                  Borgne, Bay
                                  Boudreau.
Bottlenose dolphin.............  Northern Gulf of       63,280   * 109,059       71,331           29          0     71,360           65  N/A..............  Gulf of America    Zero to small
                                  America                                                                                                                    (100 percent).     number of days.
                                  Continental
                                  Shelf.
Bottlenose dolphin.............  Nueces Bay/Corpus          58        * 41            4            0          0          4           10  N/A..............  Gulf of America    Zero to small
                                  Christi Bay.                                                                                                               (100 percent).     number of days.
Bottlenose dolphin.............  Sabine Lake......         122       * 148            1            0          0          1            1  N/A..............  Gulf of America    Zero to small
                                                                                                                                                             (100 percent).     number of days.
Bottlenose dolphin.............  St. Andrew Bay...       * 199         114           46            0          0         46           23  N/A..............  Gulf of America    Small number of
                                                                                                                                                             (100 percent).     days.
Bottlenose dolphin.............  St. Joseph Bay...       * 142          34           42            0          0         42           30  N/A..............  Gulf of America    Small number of
                                                                                                                                                             (100 percent).     days.
Bottlenose dolphin.............  Tampa Bay........         Unk       * 599          350            0          0        350           58  N/A..............  Gulf of America    Small number of
                                                                                                                                                             (100 percent).     days.
Clymene dolphin................  Northern Gulf of          513     * 3,126          599            3          0        602           19  N/A..............  Gulf of America    Zero to small
                                  America.                                                                                                                   (85 percent).      number of days.
False killer whale.............  Northern Gulf of          494     * 1,023          230            0          0        230           22  N/A..............  Gulf of America    Zero to small
                                  America.                                                                                                                   (84 percent).      number of days.
Fraser's dolphin...............  Northern Gulf of          213     * 1,081          241            0          0        241           22  N/A..............  Gulf of America    Zero to small
                                  America.                                                                                                                   (76 percent).      number of days.
Killer whale...................  Northern Gulf of          267       * 511          110            0          0        110           22  N/A..............  Gulf of America    Zero to small
                                  America.                                                                                                                   (85 percent).      number of days.
Melon-headed whale.............  Northern Gulf of        1,749     * 3,579          771            1          0        772           22  N/A..............  Gulf of America    Zero to small
                                  America.                                                                                                                   (84 percent).      number of days.
Pygmy killer whale.............  Northern Gulf of          613     * 1,278          285            0          0        285           22  N/A..............  Gulf of America    Zero to small
                                  America.                                                                                                                   (85 percent).      number of days.
Risso's dolphin................  Northern Gulf of      * 1,974         813          203            0          0        203           10  N/A..............  Gulf of America    Zero to small
                                  America.                                                                                                                   (72 percent).      number of days.
Rough-toothed dolphin..........  Northern Gulf of          Unk     * 3.452        1,642            3          0      1,645           48  N/A..............  Gulf of America    Small number of
                                  America.                                                                                                                   (92 percent).      days.
Short-finned pilot whale.......  Northern Gulf of        1,321     * 1,835        1,021            3          0      1,024           56  N/A..............  Gulf of America    Small number of
                                  America.                                                                                                                   (90 percent).      days.
Striped dolphin................  Northern Gulf of        1,817     * 7,782        2,376            7       0.29      2,384           31  Winter (40         Gulf of America    Zero to small
                                  America.                                                                                                percent).          (70 percent).      number of days.
Pantropical spotted dolphin....  Northern Gulf of     * 37,195      35,057        6,316            9       0.71      6,327           17  N/A..............  Gulf of America    Zero to small
                                  America.                                                                                                                   (71 percent).      number of days.
Spinner dolphin................  Northern Gulf of      * 2,991       1,422          656            0          0        656           22  N/A..............  Gulf of America    Zero to small
                                  America.                                                                                                                   (99 percent).      number of days.
Atlantic white-sided dolphin...  Western North        * 93,233      14,869       22,094           32          0     22,126           36  N/A..............  Northeast (69      Zero to small
                                  Atlantic.                                                                                                                  percent) Mid-      number of days.
                                                                                                                                                             Atlantic (31
                                                                                                                                                             percent).
Common dolphin.................  Western North        * 93,100      73,015       25,792            6          0     25,798            0  Winter (45         Mid-Atlantic (75   Small to moderate
                                  Atlantic.                                                                                               percent).          percent).          number of days.

[[Page 20045]]

 
Atlantic spotted dolphin.......  Western North        * 31,506      28,226      120,798           87          0    120,885          384  N/A..............  Mid-Atlantic (59   Small to moderate
                                  Atlantic.                                                                                                                  percent).          number of days.
Bottlenose dolphin.............  Indian River          * 1,032         484        1,576            0          0      1,576          153  Fall (43 percent)  Southeast (100     Small number of
                                  Lagoon Estuarine                                                                                                           percent).          days.
                                  System.
Bottlenose dolphin.............  Jacksonville              Unk          19          360            0          0        360          Und  Fall (45 percent)  Southeast (100     Moderate number
                                  Estuarine System.                                                                                                          percent).          of days.
Bottlenose dolphin.............  Northern Georgia/         Unk          19            2            0          0          2          Und  N/A..............  Southeast (100     Zero to small
                                  Southern South                                                                                                             percent).          number of days.
                                  Carolina
                                  Estuarine System.
Bottlenose dolphin.............  Northern North            823     * 1,227       10,532            6          0     10,538          859  Summer (98         Mid-Atlantic (100  High number of
                                  Carolina                                                                                                percent).          percent).          days.
                                  Estuarine System.
Bottlenose dolphin.............  Southern Georgia          Unk       * 619          123            1          0        124           20  N/A..............  Southeast (100     Small number of
                                  Estuarine System.                                                                                                          percent).          days.
Bottlenose dolphin.............  Southern North            Unk       * 486          162            0          0        162           33  Fall (60 percent)  Mid-Atlantic (99   Small number of
                                  Carolina                                                                                                                   percent).          days.
                                  Estuarine System.
Tamanend's Bottlenose Dolphin..  Western North           2,541     * 7,063       10,494            3          0     10,497          149  N/A..............  Southeast (100     Small number of
                                  Atlantic,                                                                                                                  percent).          days.
                                  Central Florida
                                  Coastal.
Tamanend's Bottlenose Dolphin..  Western North         * 3,619       2,598       21,385            5          0     21,390          591  N/A..............  Southeast (100     Moderate number
                                  Atlantic,                                                                                                                  percent).          of days.
                                  Northern Florida
                                  Coastal.
Bottlenose dolphin.............  Western North           6,639    * 10,325       73,720           60          0     73,780          715  N/A..............  Mid-Atlantic (100  Moderate number
                                  Atlantic                                                                                                                   percent).          of days.
                                  Northern
                                  Migratory
                                  Coastal.
Bottlenose dolphin.............  Western North          64,587   * 150,704      187,046          103       0.29    187,151          124  N/A..............  Mid-Atlantic (60   Small number of
                                  Atlantic                                                                                                                   percent).          days.
                                  Offshore.
Tamanend's Bottlenose Dolphin..  Western North         * 9,121       4,105        4,960            6       0.14      4,967           54  N/A..............  Southeast (95      Zero to small
                                  Atlantic South                                                                                                             percent).          number of days.
                                  Carolina/Georgia
                                  Coastal.
Bottlenose dolphin.............  Western North           3,751     * 7,911       10,180            9          0     10,189        1,549  N/A..............  Mid-Atlantic (60   Small number of
                                  Atlantic                                                                                                                   percent)           days.
                                  Southern                                                                                                                   Southeast (40
                                  Migratory                                                                                                                  percent).
                                  Coastal.
Clymene dolphin................  Western North        * 21,778       8,573      132,723          104       0.43    132,828           44  N/A..............  Mid-Atlantic (98   Moderate number
                                  Atlantic.                                                                                                                  percent).          of days.
False killer whale.............  Western North         * 1,298          97          572            1          0        573          Und  Winter (40         Mid-Atlantic (48   Zero to small
                                  Atlantic.                                                                                               percent).          percent).          number of days.
Fraser's dolphin...............  Western North             Unk       * 518        2,905            3          0      2,908          561  N/A..............  Southeast (52      Moderate number
                                  Atlantic.                                                                                                                  percent).          of days.
Killer whale...................  Western North             Unk        * 51          180            1          0        181          355  N/A..............  Mid-Atlantic (61   Small to moderate
                                  Atlantic.                                                                                                                  percent).          number of days.
Long-finned pilot whale........  Western North        * 39,215       5,392       21,680           12          0     21,692           55  N/A..............  Mid-Atlantic (84   Zero to small
                                  Atlantic.                                                                                                                  percent).          number of days.
Melon-headed whale.............  Western North             Unk       * 495        4,598            3          0      4,601          929  N/A..............  Southeast (43      Moderate number
                                  Atlantic.                                                                                                                  percent).          of days.
Pantropical spotted dolphin....  Western North         * 2,757       1,147       13,068            5          0     13,073          474  N/A..............  High Seas (54      Moderate number
                                  Atlantic.                                                                                                                  percent).          of days.
Pygmy killer whale.............  Western North             Unk        * 54          477            1          0        478          885  N/A..............  Southeast (45      Moderate number
                                  Atlantic.                                                                                                                  percent).          of days.
Risso's dolphin................  Western North        * 44,067      12,845       37,239           25          0     37,264           85  N/A..............  Mid-Atlantic (40   Zero to small
                                  Atlantic.                                                                                                                  percent).          number of days.
Rough-toothed dolphin..........  Western North             Unk       * 824        4,753            6          0      4,759          578  N/A..............  Southeast (55      Moderate number
                                  Atlantic.                                                                                                                  percent).          of days.
Short-finned pilot whale.......  Western North        * 18,726       6,235       33,035           15          0     33,050          176  N/A..............  Mid-Atlantic (54   Small number of
                                  Atlantic.                                                                                                                  percent).          days.
Spinner dolphin................  Western North         * 3,181         646        5,356            2          0      5,358          168  Winter (40         N/A..............  Small number of
                                  Atlantic.                                                                                               percent).                             days.
Striped dolphin................  Western North        * 48,274      43,044      208,802          163          0    208,965          433  N/A..............  Mid-Atlantic (89   Small to moderate
                                  Atlantic.                                                                                                                  percent).          number of days.
White-beaked dolphin...........  Western North       * 536,016          44           16            0          0         16            0  N/A..............  Northeast (92      Zero to small
                                  Atlantic.                                                                                                                  percent).          number of days.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Unk = Unknown; N/A = Not Applicable. NMSDD abundances are averages only within the U.S. EEZ.
* Indicates which abundance estimate was used to calculate the maximum annual take as a percentage of abundance, either the NMFS SAR (Hayes et al., 2024) or the NMSDD (table 2.4-1 in appendix
  A of the application). Please refer to the following section for details on which abundance estimate was selected.


[[Page 20046]]


                                                                                        Table 88--Life History Traits, Important Habitat, and Threats to Dolphins in the AFTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                                                                                                                                        Annual
                                                                                                                         Reproductive     Pace  of      Chronic risk      UME, oil    ESA- designated  BIAs (Labrecque   Other important                              mortality/
     Marine mammal species              Stock        ESA  status      MMPA status      Movement ecology    Body size       strategy         life          factors       spill, other      critical       et al. 2015)        habitat        Population trend    PBR     serious
                                                                                                                                                                                          habitat                                                                       injury
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Atlantic spotted dolphin.......  Northern Gulf of    Not Listed.  Not Depleted......  Migratory.........  Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Unk..............     166          36
                                  America.                        Not Strategic.....                                                                  fishery
                                                                                                                                                      interaction,
                                                                                                                                                      ocean noise,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      energy
                                                                                                                                                      exploration and
                                                                                                                                                      development, oil
                                                                                                                                                      spills, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Gulf of America     Not Listed.  Not Depleted......  Nomadic-resident..  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Unk, potentially      114         9.2
                                  Eastern Coastal.                Not Strategic.....                                                                  chemical                                                                              increasing.
                                                                                                                                                      contaminants,
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Gulf of America     Not Listed.  Not Depleted......  Nomadic-resident..  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Unk, potentially       89          28
                                  Northern Coastal.               Not Strategic.....                                                                  chemical                                                                              increasing.
                                                                                                                                                      contaminants,
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Northern Gulf of    Not Listed.  Not Depleted......  Nomadic- resident.  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Stable...........      58          32
                                  America Oceanic.                Not Strategic.....                                                                  chemical
                                                                                                                                                      contaminants,
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.

[[Page 20047]]

 
Bottlenose dolphin.............  Gulf of America     Not Listed.  Not Depleted......  Nomadic- resident.  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Unk, potentially      167          36
                                  Western Coastal.                Not Strategic.....                                                                  chemical                                                                              stable.
                                                                                                                                                      contaminants,
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Mississippi Sound,  Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  Mississippi Sound  Unk, potentially      8.5          59
                                  Lake Borgne, Bay                Strategic.........                                                                  chemical                                                           and associated     stable.
                                  Boudreau.                                                                                                           contaminants,                                                      waters \a\.
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Northern Gulf of    Not Listed.  Not Depleted......  Nomadic-resident..  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Unk, potentially      556          65
                                  America                         Not Strategic.....                                                                  chemical                                                                              increasing.
                                  Continental Shelf.                                                                                                  contaminants,
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Nueces Bay/Corpus   Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  Nueces Bay/Corpus  Unk (insufficient     Und         0.2
                                  Christi Bay.                    Strategic.........                                                                  chemical                                                           Christi Bay,       data).
                                                                                                                                                      contaminants,                                                      Corpus Christi/
                                                                                                                                                      fishery                                                            Aransas Pass \b\.
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.

[[Page 20048]]

 
Bottlenose dolphin.............  Sabine Lake.......  Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  Sabine Pass        Unk (insufficient     0.9           0
                                                                  Not Strategic.....                                                                  chemical                                                           Channel, lower     data).
                                                                                                                                                      contaminants,                                                      Sabine Lake
                                                                                                                                                      fishery                                                            south of Blue
                                                                                                                                                      interaction,                                                       Buck Point,
                                                                                                                                                      habitat                                                            areal shipping
                                                                                                                                                      alteration,                                                        channels \c\.
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  St. Andrew Bay....  Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  St. Andrew Bay,    Unk (insufficient     1.5         0.2
                                                                  Not Strategic.....                                                                  chemical                                                           West Bay, East     data).
                                                                                                                                                      contaminants,                                                      Bay, and North
                                                                                                                                                      fishery                                                            Bay \d\.
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  St. Joseph Bay....  Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  St. Joseph Bay,    Stable...........       1         Unk
                                                                  Not Strategic.....                                                                  chemical                                                           Crooked Island
                                                                                                                                                      contaminants,                                                      Sound \e\.
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.

[[Page 20049]]

 
Bottlenose dolphin.............  Tampa Bay.........  Not Listed.  Not Depleted......  Nomadic-resident..  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  Tampa Bay \f\....  Unk (Insufficient     Und           3
                                                                  Strategic.........                                                                  chemical                                                                              data).
                                                                                                                                                      contaminants,
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Clymene dolphin................  Northern Gulf of    Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Fast......  Fishery            No..........  No.............  No.............  None identified..  Likely increasing     2.5         8.4
                                  America.                        Strategic.........                                                                  interaction,
                                                                                                                                                      Deepwater
                                                                                                                                                      horizon, energy
                                                                                                                                                      exploration and
                                                                                                                                                      development, oil
                                                                                                                                                      spills, climate
                                                                                                                                                      change.
False killer whale.............  Northern Gulf of    Not Listed.  Not Depleted......  Resident- nomadic.  Med........  Income..........  Med.......  Fishery            No..........  No.............  No.............  None identified..  Decreasing.......     2.8         2.2
                                  America.                        Not Strategic.....                                                                  interaction,
                                                                                                                                                      contaminants,
                                                                                                                                                      hunting,
                                                                                                                                                      Deepwater
                                                                                                                                                      Horizon and
                                                                                                                                                      other oil
                                                                                                                                                      spills, disease,
                                                                                                                                                      climate change.
Fraser's dolphin...............  Northern Gulf of    Not Listed.  Not Depleted......  Resident- nomadic.  Small......  Income..........  Fast......  Fishery            No..........  No.............  No.............  None identified..  Unk..............       1         Unk
                                  America.                        Not Strategic.....                                                                  interaction,
                                                                                                                                                      energy
                                                                                                                                                      exploration and
                                                                                                                                                      development, oil
                                                                                                                                                      spills, climate
                                                                                                                                                      change.
Killer whale...................  Northern Gulf of    Not Listed.  Not Depleted......  Resident..........  Large......  Income..........  Slow......  Chemical           No..........  No.............  No.............  None identified..  Unk..............     1.5         Unk
                                  America.                        Not Strategic.....                                                                  contaminants,
                                                                                                                                                      vessel traffic
                                                                                                                                                      and noise,
                                                                                                                                                      entanglement,
                                                                                                                                                      oil spills,
                                                                                                                                                      energy
                                                                                                                                                      exploration and
                                                                                                                                                      development,
                                                                                                                                                      climate change.
Melon-headed whale.............  Northern Gulf of    Not Listed.  Not Depleted......  Resident- nomadic.  Small......  Income..........  Med.......  Fishery            No..........  No.............  No.............  None identified..  Unk..............      10         9.5
                                  America.                        Not Strategic.....                                                                  interaction,
                                                                                                                                                      ocean noise,
                                                                                                                                                      pollution,
                                                                                                                                                      energy
                                                                                                                                                      exploration and
                                                                                                                                                      development, oil
                                                                                                                                                      spills, climate
                                                                                                                                                      change.
Pygmy killer whale.............  Northern Gulf of    Not Listed.  Not Depleted......  Resident-nomadic..  Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Unk..............     2.8         1.6
                                  America.                        Not Strategic.....                                                                  ocean noise, oil
                                                                                                                                                      spill, oil and
                                                                                                                                                      gas exploration,
                                                                                                                                                      climate change.

[[Page 20050]]

 
Risso's dolphin................  Northern Gulf of    Not Listed.  Not Depleted......  Resident-nomadic..  Small-Med..  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Unk (Insufficient      14         5.3
                                  America.                        Not Strategic.....                                                                  environmental                                                                         data).
                                                                                                                                                      contamination,
                                                                                                                                                      hunting, ocean
                                                                                                                                                      noise, energy
                                                                                                                                                      exploration and
                                                                                                                                                      development, oil
                                                                                                                                                      spills, climate
                                                                                                                                                      change.
Rough-toothed dolphin..........  Northern Gulf of    Not Listed.  Not Depleted......  Resident-nomadic..  Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Unk..............     Und          39
                                  America.                        Not Strategic.....                                                                  ocean noise,
                                                                                                                                                      energy
                                                                                                                                                      exploration and
                                                                                                                                                      development, oil
                                                                                                                                                      spills, climate
                                                                                                                                                      change.
Short-finned pilot whale.......  Northern Gulf of    Not Listed.  Not Depleted......  Resident..........  Med........  Income..........  Slow......  Entanglement,      No..........  No.............  No.............  None identified..  Unk..............     7.5         3.9
                                  America.                        Not Strategic.....                                                                  fishery
                                                                                                                                                      interaction,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      energy
                                                                                                                                                      exploration and
                                                                                                                                                      development, oil
                                                                                                                                                      spills, climate
                                                                                                                                                      change.
Striped dolphin................  Northern Gulf of    Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Unk..............      12          13
                                  America.                        Strategic.........                                                                  energy
                                                                                                                                                      exploration and
                                                                                                                                                      development, oil
                                                                                                                                                      spills, disease,
                                                                                                                                                      climate change.
Pantropical spotted dolphin....  Northern Gulf of    Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Med.......  Fishery            No..........  No.............  No.............  None identified..  Unk (Insufficient     Unk           0
                                  America.                        Not Strategic.....                                                                  interaction,                                                                          data).
                                                                                                                                                      ocean noise,
                                                                                                                                                      pollution,
                                                                                                                                                      climate change.
Spinner dolphin................  Northern Gulf of    Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Stable,                19           0
                                  America.                        Strategic.........                                                                  Illegal feeding/                                                                      potentially
                                                                                                                                                      harassment,                                                                           increasing.
                                                                                                                                                      climate change.
Atlantic white-sided dolphin...  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Fast......  Entanglement,      No..........  No.............  No.............  None identified..  Unk..............     544          28
                                  Atlantic.                       Not Strategic.....                                                                  ocean noise,
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      hunting
                                                                                                                                                      (Newfoundland,
                                                                                                                                                      Canada,
                                                                                                                                                      Greenland),
                                                                                                                                                      climate change.
Common dolphin.................  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Unk..............   1,452         414
                                  Atlantic.                       Not Strategic.....                                                                  climate change.
Atlantic spotted dolphin.......  Western North       Not Listed.  Not Depleted......  Unk, likely         Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Decreasing.......     250           0
                                  Atlantic.                       Not Strategic.....   nomadic.                                                       ocean noise,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      climate change.

[[Page 20051]]

 
Bottlenose dolphin.............  Indian River        Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  Indian River       Unk (insufficient      10         5.7
                                  Lagoon Estuarine                Strategic.........                                                                  chemical                                                           Lagoon Estuarine   data).
                                  System.                                                                                                             contaminants,                                                      System \g\.
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Jacksonville        Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  Yes: Small and   Jacksonville       Unk (insufficient     Unk           2
                                  Estuarine System.               Strategic.........                                                                  chemical                                          resident         Estuarine System   data).
                                                                                                                                                      contaminants,                                     population.      \h\.
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Northern Georgia/   Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  St. Helena Sound,  Unk (insufficient     Unk          59
                                  Southern South                  Strategic.........                                                                  chemical                                                           South Carolina     data).
                                  Carolina                                                                                                            contaminants,                                                      to Ossabaw
                                  Estuarine System.                                                                                                   fishery                                                            Sound, Georgia
                                                                                                                                                      interaction,                                                       \i\.
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Northern North      Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  Yes: Small and   Northern North     Unk (potentially      7.8      7.2-30
                                  Carolina                        Strategic.........                                                                  chemical                                          resident         Carolina           stable).
                                  Estuarine System.                                                                                                   contaminants,                                     population.      Estuarine System
                                                                                                                                                      fishery                                                            \j\.
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.

[[Page 20052]]

 
Bottlenose dolphin.............  Southern Georgia    Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  Yes: Small and   Southern Georgia   Unk (insufficient     Und         0.1
                                  Estuarine System.               Not Strategic.....                                                                  chemical                                          resident         Estuarine System   data).
                                                                                                                                                      contaminants,                                     population.      \k\.
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Southern North      Not Listed.  Not Depleted......  Resident..........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  Yes: Small and   Southern North     Unk..............     Und         0.4
                                  Carolina                        Strategic.........                                                                  chemical                                          resident         Carolina
                                  Estuarine System.                                                                                                   contaminants,                                     population.      Estuarine System
                                                                                                                                                      fishery                                                            \l\.
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Tamanend's Bottlenose Dolphin..  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Unk (insufficient      18         0.2
                                  Atlantic, Central               Strategic.........                                                                  chemical                                                                              data).
                                  Florida Coastal.                                                                                                    contaminants,
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.

[[Page 20053]]

 
Tamanend's Bottlenose Dolphin..  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Unk (insufficient      27         0.2
                                  Atlantic,                       Strategic.........                                                                  chemical                                                                              data).
                                  Northern Florida                                                                                                    contaminants,
                                  Coastal.                                                                                                            fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Western North       Not Listed.  Not Depleted......  Migratory.........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Decreasing.......      48   12.2-21.5
                                  Atlantic Northern               Strategic.........                                                                  chemical
                                  Migratory Coastal.                                                                                                  contaminants,
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Bottlenose dolphin.............  Western North       Not Listed.  Not Depleted......  Migratory.........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Stable,               507          28
                                  Atlantic Offshore.              Not Strategic.....                                                                  chemical                                                                              potentially
                                                                                                                                                      contaminants,                                                                         decreasing.
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Tamanend's Bottlenose Dolphin..  Western North       Not Listed.  Not Depleted......  Migratory.........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Unk (insufficient      73     0.2-0.6
                                  Atlantic South                  Strategic.........                                                                  chemical                                                                              data).
                                  Carolina/Georgia                                                                                                    contaminants,
                                  Coastal.                                                                                                            fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.

[[Page 20054]]

 
Bottlenose dolphin.............  Western North       Not Listed.  Not Depleted......  Migratory.........  Small-Med..  Income..........  Med.......  Biotoxins,         No..........  No.............  No.............  None identified..  Decreasing.......      24      0-18.3
                                  Atlantic Southern               Strategic.........                                                                  chemical
                                  Migratory Coastal.                                                                                                  contaminants,
                                                                                                                                                      fishery
                                                                                                                                                      interaction,
                                                                                                                                                      habitat
                                                                                                                                                      alteration,
                                                                                                                                                      illegal feeding/
                                                                                                                                                      harassment,
                                                                                                                                                      ocean noise, oil
                                                                                                                                                      spills and
                                                                                                                                                      energy
                                                                                                                                                      exploration,
                                                                                                                                                      vessel strikes,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Clymene dolphin................  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Fast......  Entanglement,      No..........  No.............  No.............  None identified..  Unk..............     126           0
                                  Atlantic.                       Not Strategic.....                                                                  fishery
                                                                                                                                                      interaction,
                                                                                                                                                      ocean noise,
                                                                                                                                                      PCBs, hunting
                                                                                                                                                      (Caribbean),
                                                                                                                                                      climate change.
False killer whale.............  Western North       Not Listed.  Not Depleted......  Nomadic...........  Med........  Income..........  Med.......  Fishery            No..........  No.............  No.............  None identified..  Unk (Insufficient     7.6           0
                                  Atlantic.                       Not Strategic.....                                                                  interaction,                                                                          data).
                                                                                                                                                      contaminants,
                                                                                                                                                      hunting,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Fraser's dolphin...............  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Fast......  Fishery            No..........  No.............  No.............  None identified..  Unk..............     Unk           0
                                  Atlantic.                       Not Strategic.....                                                                  interaction,
                                                                                                                                                      climate change.
Killer whale...................  Western North       Not Listed.  Not Depleted......  Nomadic...........  Large......  Income..........  Slow......  Chemical           No..........  No.............  No.............  None identified..  Unk..............     Unk           0
                                  Atlantic.                       Not Strategic.....                                                                  contaminants,
                                                                                                                                                      vessel traffic
                                                                                                                                                      and noise,
                                                                                                                                                      entanglement,
                                                                                                                                                      oil spills,
                                                                                                                                                      climate change.
Long-finned pilot whale........  Western North       Not Listed.  Not Depleted......  Nomadic...........  Med........  Income..........  Slow......  Entanglements,     No..........  No.............  No.............  None identified..  Unk..............     306         5.7
                                  Atlantic.                       Not Strategic.....                                                                  contaminants,
                                                                                                                                                      ocean noise,
                                                                                                                                                      disease, climate
                                                                                                                                                      change.
Melon-headed whale.............  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Med.......  Fishery            No..........  No.............  No.............  None identified..  Unk (Insufficient     Unk           0
                                  Atlantic.                       Not Strategic.....                                                                  interaction,                                                                          data).
                                                                                                                                                      ocean noise,
                                                                                                                                                      pollution,
                                                                                                                                                      climate change.
Pantropical spotted dolphin....  Western North       Not Listed.  Depleted..........  Nomadic...........  Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Stable,                19           0
                                  Atlantic.                       Not Strategic.....                                                                  Illegal feeding/                                                                      potentially
                                                                                                                                                      harassment,                                                                           increasing.
                                                                                                                                                      climate change.
Pygmy killer whale.............  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Unk (Insufficient     Unk           0
                                  Atlantic.                       Not Strategic.....                                                                  ocean noise,                                                                          data).
                                                                                                                                                      climate change.

[[Page 20055]]

 
Risso's dolphin................  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small-Med..  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Unk (Insufficient     307          18
                                  Atlantic.                       Not Strategic.....                                                                  environmental                                                                         data).
                                                                                                                                                      contamination,
                                                                                                                                                      hunting, ocean
                                                                                                                                                      noise, climate
                                                                                                                                                      change.
Rough-toothed dolphin..........  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Unk (Insufficient     Und           0
                                  Atlantic.                       Not Strategic.....                                                                  ocean noise,                                                                          data).
                                                                                                                                                      climate change.
Short-finned pilot whale.......  Western North       Not Listed.  Not Depleted......  Resident-nomadic..  Med........  Income..........  Slow......  Entanglement,      No..........  No.............  No.............  Mid-Atlantic       Stable...........     143         218
                                  Atlantic.                       Strategic.........                                                                  fishery                                                            Bight Canyons
                                                                                                                                                      interaction,                                                       \m\.
                                                                                                                                                      vessel strikes,
                                                                                                                                                      climate change.
Spinner dolphin................  Western North       Not Listed.  Depleted..........  Nomadic...........  Small......  Income..........  Fast......  Marine debris,     No..........  No.............  No.............  None identified..  Unk..............      19           0
                                  Atlantic.                       Not Strategic.....                                                                  ocean noise,
                                                                                                                                                      disease.
Striped dolphin................  Western North       Not Listed.  Not Depleted......  Nomadic...........  Small......  Income..........  Med.......  Entanglement,      No..........  No.............  No.............  None identified..  Unk..............     529           0
                                  Atlantic.                       Not Strategic.....                                                                  disease, climate
                                                                                                                                                      change.
White-beaked dolphin...........  Western North       Not Listed.  Not Depleted......  Nomadic-migratory.  Small......  Income..........  Fast......  Entanglement,      No..........  No.............  No.............  None identified..  Unk..............   4,153           0
                                  Atlantic.                       Not Strategic.....                                                                  climate change.
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Unk = Unknown, Und = Undetermined.
\a\ See Hubard et al. (2004), Mackey (2010), Arick et al. (2024), McBride (2013), Miller et al. (2013), Mullin et al. (2017), and Vollmer et al. (2021) for more information.
\b\ See Ronje et al. (2022), Shane (1980, Weller (1998), and W[uuml]rsig et al. (2022) for more information.
\c\ See Ronje et al. (2020), Ronje et al. (2021), Ronje et al. (2022), Wells (2014), and W[uuml]rsig et al. (2022) for more information.
\d\ See Balmer et al. (2008), Balmer et al. (2010), Balmer et al. (2018), Balmer et al. (2019a), Balmer et al. (2019b), Blaylock and Hoggard (1994), Bouveroux et al. (2014), Colborn (1999), Hayes et al. (2020), Kendall et al. (1997), Pollock (1982), Pollock et al. (1990),
  Powell et al. (2018), Samuels and Bejder (2004), and Samuels and Spradlin (1995) for more information.
\e\ See Balmer et al. (2008), Balmer et al. (2010), Balmer et al. (2016), Balmer et al. (2018), Balmer et al. (2019a), Balmer et al. (2019b), Bouveroux et al. (2014), Burnham and Overton (1978), Burnham and Overton (1979), Chapman (1951), Cush (2016), Cush et al. (2019),
  Darroch (1958), Hayes et al. (2020), Hubard et al. (2004), Kendall et al. (1997), Rosel et al. (2011), Schwacke et al (2010), and Toms (2019) for more information.
\f\ See Bassos (1993), Bassos-Hull et al. (2013), Boyd et al. (2021), Duffield and Wells (2002), Irvine and Wells (1972), Irvine et al. (1981), Leatherwood and Show (1980), Mate et al. (1995), McCallister (2011), Odell and Reynolds (1980), Scott et al. (1989), Sellas et
  al. (2005), Simard et al. (2011), Thompson (1981), Urian et al. (2009), van Ginkel et al. (2018), Weigle (1990), Wells (1986), Wells (2014), Wells et al. (1998), Wells et al. (1996), Wells et al. (1987), and Wells et al. (2013) for more information.
\g\ See Durden et al. (2017), Durden et al. (2021), Odell and Asper (1990), Mazzoil et al. (2005), Mazzoil et al. (2008a), Mazzoil et al. (2008b), and Mazzoil et al. (2020) for more information.
\h\ See Caldwell (2001), and Mazzoil et al. (2020) for more information.
\i\ See Gubbins (2000a), Gubbins (2000b), Gubbins (2000c), and Waring et al. (2014) for more information.
\j\ See Garrison et al. (2017) and Gorgone et al. (2014) for more information.
\k\ See Pulster and Maruya (2008) and Balmer et al. (2013) for more information.
\l\ See Urian et al. (1999), Read et al. (2003), Waring et al. (2014), and Silva et al. (2020) for more information.
\m\ See Thorne et al. (2017) for more information.


[[Page 20056]]

    As shown in table 87, the maximum annual allowable instances of 
take by Level B harassment for Delphinid stocks ranges from 1 (Sabine 
Lake bottlenose dolphin stock) to 269,405 for the Western North 
Atlantic common dolphin, with 24 stocks below 2,000, seven stocks above 
70,000, and the remainder between 2,000 and 38,000. Take by Level A 
harassment is 0 for 17 of the 53 stocks, above 15 for 11 stocks, and 11 
or fewer for the remaining stocks. As indicated, the rule also allows 
for 1-2 takes annually by serious M/SI for five stocks (the Northern 
Gulf of America stocks of striped and pantropical dolphins, the Western 
North Atlantic offshore stock of bottlenose dolphins, the Western North 
Atlantic South Carolina/Georgia Coastal stock of Tamanend's bottlenose 
dolphin, and the Western North Atlantic stock of Clymene dolphins), the 
impacts of which are discussed above in the Mortality section. The 
total take allowable across all 7 years of the rule is indicated in 
table 49.
    All but two Delphinid stocks are expected to incur some number of 
takes in the form of TTS. As described in the Auditory Injury from 
Sonar Acoustic Sources and Explosives and Non-Auditory Injury from 
Explosives section above, these temporary hearing impacts are expected 
to be lower-level, of short duration (from minutes to at most several 
hours or less than a day), and mostly not in a frequency band that 
would be expected to interfere with delphinid echolocation, overlap 
more than a relatively narrow portion of the vocalization range of any 
single species or stock, or preclude detection or interpretation of 
important low-frequency cues. Any associated lost opportunities or 
capabilities individuals might experience as a result of TTS would not 
be at a level or duration that would be expected to impact reproductive 
success or survival. About two-thirds of the affected Delphinid stocks 
will incur some number of takes by AUD INJ, the majority of single 
digits, with higher numbers exceding 50 and up to 161 for several 
stocks. For reasons similar to those discussed for TTS, while AUD INJ 
impacts are permanent, given the anticipated effectiveness of the 
mitigation and the likelihood that individuals are expected to avoid 
higher levels associated with more severe impacts, the lower 
anticipated levels of PTS that could be reasonably expected to result 
from these activities are unlikely to affect the fitness of any 
individuals. Five stocks are projected to incur notably higher numbers 
of take by AUD INJ (85-161, the Western North Atlantic stocks of 
Atlantic spotted dolphins, common dolphins, Clymene dolphins, striped 
dolphins, and offshore bottlenose dolphins) and while the conclusions 
above are still applicable, it is further worth noting that these five 
stocks have relatively large abundances and limited annual mortality as 
compared to PBR. The rule also allows for a limited number of takes by 
non-auditory injury (1-3) for 15 stocks. As described above in the 
Auditory Injury from Sonar Acoustic Sources and Explosives and Non-
Auditory Injury from Explosives section, given the small number of 
potential exposures and the anticipated effectiveness of the mitigation 
measures in minimizing the pressure levels to which any individuals are 
exposed, these non-auditory injuries are unlikely to be of a nature or 
level that would impact reproduction or survival.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 178 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, foraging 
interruptions, vocalization changes, or disruption of other social 
behaviors, lasting from a few minutes to several hours. Delphinids are 
income breeders with a medium pace of life, meaning that while they can 
be sensitive to the consequences of disturbances that impact foraging 
during lactation, from a population standpoint, they can be moderately 
quick to recover. Further, as described in the Group and Species-
Specific Analyses section above and the Proposed Mitigation Measures 
section, mitigation measures are expected to further reduce the 
potential severity of impacts through real-time operational measures 
that minimize higher level/longer duration exposures and time/area 
measures that reduce impacts in higher value habitat.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In the case of just over 
half of the delphinid stocks (see the Maximum Annual Harassment As 
Percentage of Stock Abundance column in table 87), given the low number 
of takes by harassment as compared to the stock/species abundance 
alone, and also in consideration of their migratory movement pattern 
and whether take is concentrated in areas in which animals are known to 
congregate, it is unlikely that these individual Delphinids would be 
taken on more than a small number of days within a year and, therefore, 
the anticipated behavioral disturbance is not expected to affect 
reproduction or survival. In the case of the rest of the stocks, with 
the exception of the Northern North Carolina Estuarine System stock of 
bottlenose dolphins (addressed below), given the number of takes by 
harassment as compared to the stock/species abundance, it is likely 
that some portion of the individuals taken are taken repeatedly over a 
small to moderate number of days (as indicated in the Greatest Degree 
Any Individual Expected to be Taken Repeatedly Across Multiple days 
column of table 87). However, given the variety of activity types that 
contribute to take across separate exercises conducted at different 
times and in different areas, and the fact that many result from 
transient activities conducted at sea, for all but one of the stocks 
(addressed below), it is unlikely that the anticipated small to 
moderate number of repeated takes for a given individual would occur 
clumped across sequential days in a manner likely to impact foraging 
success and energetics or other behaviors such that reproduction or 
survival of any individuals are likely to be impacted. Further, many of 
these stocks are nomadic or migratory and apart from the few small 
resident dolphin populations, there are no known foraging areas or 
other areas within which animals are known to congregate for important 
behaviors, and nor are the takes concentrated within a specific region 
and season.
    Regarding the magnitude of repeated takes for the Northern North 
Carolina Estuarine System stock of bottlenose dolphins, given the 
number of takes by harassment as compared to the stock/species 
abundance, the small resident population, the fact that the predicted 
takes all occur in summer and are primarily from hull-mounted sonar 
pierside or navigating out of Norfolk (see appendix A to the 
application), it is more likely that some number of individuals 
occupying that area during the summer months would experience a 
comparatively higher number of repeated takes over a potentially fair 
number of sequential days. Due to the higher number of repeated takes 
focused within a limited time period, it is thereby more likely that a 
portion of the individuals occupying the area near Norfolk in the 
summer (approximately 50 percent of which would be female) could be 
repeatedly interrupted during foraging in a manner and amount such that 
impacts to the energy budgets of a

[[Page 20057]]

small number of females (from either losing feeding opportunities or 
expending considerable energy moving away from sound sources or finding 
alternative feeding options) could cause them to forego reproduction 
for a year (noting that bottlenose dolphin calving intervals are 
typically three or more years). Energetic impacts to males are 
generally meaningless to population rates unless they cause death, and 
it takes extreme energy deficits beyond what would ever be likely to 
result from these activities to cause the death of an adult marine 
mammal, male or female. This stock is considered potentially stable 
and, while strategic, is not depleted. Importantly, the increase in a 
calving interval by a year would have far less of an impact on a 
population rate than a mortality would and, accordingly, a small number 
of instances of foregone reproduction would not be expected to 
adversely affect this stock through effects on annual rates of 
recruitment or survival (noting also that no mortality is predicted or 
authorized for this stock).
    Given the magnitude and severity of the take by harassment 
discussed above and any anticipated habitat impacts, and in 
consideration of the required mitigation measures and other information 
presented, the Action Proponents' activities are unlikely to result in 
impacts on the reproduction or survival of any individuals of Delphinid 
stocks, with the exception of the five stocks for which 1-2 takes by M/
SI are predicted and the one stock for which an increased calving 
interval could potentially occur. Regarding the Northern North Carolina 
Estuarine System stock of bottlenose dolphins, as described above, we 
do not anticipate the relatively small number of individuals that might 
be taken over repeated days within the year in a manner that results in 
a year of foregone reproduction to adversely affect the stock through 
effects on rates of recruitment or survival, given the status of the 
stock. Regarding the Northern Gulf of America stocks of striped and 
pantropical dolphins, the Western North Atlantic offshore stock of 
bottlenose dolphins, the Western North Atlantic offshore South 
Carolina/Georgia stock of Tamanend's bottlenose dolphins, and the 
Western North Atlantic Clymene dolphins, as described in the Mortality 
section, given the status of the stocks and in consideration of other 
ongoing anthropogenic mortality, the amount of allowed M/SI take 
proposed here would not, alone, nor in combination with the impacts of 
the take by harassment discussed above (which are not expected to 
impact the reproduction or survival of any individuals for those 
stocks), be expected to adversely affect rates of recruitment and 
survival. Last, we are aware that some Northern Gulf of America stocks 
of delphinids have experienced lower rates of reproduction and survival 
since the DWH oil spill, however, those effects are reflected in the 
SARs and other data considered in these analyses and do not change our 
findings. For these reasons, we have determined that the total take 
(considering annual maxima and across seven years) anticipated and 
proposed for authorization would have a negligible impact on all 
Delphinid species and stocks.
Porpoises--
    Harbor porpoise are not listed as endangered or threatened under 
the ESA, and the Gulf of Maine/Bay of Fundy stock is not considered 
depleted or strategic under the MMPA. The stock abundance is 85,765 
animals. There are no UMEs or other factors that cause particular 
concern for this stock. A small and resident population BIA has been 
identified for this stock (LeBrecque et al., 2015). There is no ESA-
designated critical habitat for harbor porpoise, as the species is not 
ESA-listed. While the Gulf of Maine/Bay of Fundy stock of harbor 
porpoises can be found from Greenland to North Carolina, they are 
primarily concentrated in the southern Bay of Fundy and northern Gulf 
of Maine during warmer months (summer), and from Maine to New Jersey 
during colder months (fall and spring). Harbor porpoises face several 
chronic anthropogenic and non-anthropogenic risk factors, including 
fishery interaction, ocean noise, and climate change.

[[Page 20058]]



                      Table 89--Annual Estimated Take by Level B Harassment, Level A Harassment, and Mortality and Related Information for Porpoises in the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                        Maximum
                                                                                                                                        annual
                                                                                       Maximum      Maximum     Maximum    Maximum    harassment      Season(s) with 40      Region(s) with 40
       Marine mammal species                  Stock          NMFS stock     NMSDD       annual       annual      annual     annual        as         percent of take or      percent of take or
                                                              abundance   abundance    Level B      Level A    mortality     take     percentage           greater                greater
                                                                                      harassment   harassment                          of stock
                                                                                                                                       abundance
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor porpoise....................  Gulf of Maine/Bay of      * 85,765      10,270       87,119          147          0     87,266           102  Winter (48 percent).    Northeast (85
                                      Fundy.                                                                                                        Spring (45 percent).    percent).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: NMSDD abundances are averages only within the U.S. EEZ.
* Indicates which abundance estimate was used to calculate the maximum annual take as a percentage of abundance, either the NMFS SAR (Hayes et al., 2024) or the NMSDD (table 2.4-1 in appendix
  A of the application). Please refer to the following section for details on which abundance estimate was selected.


                                                                                        Table 90--Life History Traits, Important Habitat, and Threats to Porpoises in the AFTT Study Area
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                                                                                                                                        Annual
                                                                                       Movement                        Reproductive                      Chronic risk   UME, oil spill,   ESA-designated  BIAs (LaBrecque  Other important     Population             mortality/
    Marine mammal species            Stock          ESA status      MMPA status        ecology         Body size         strategy       Pace of life       factors           other           critical       et al. 2015)       habitat           trend         PBR      serious
                                                                                                                                                                                             habitat                                                                    injury
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor porpoise..............  Gulf of Maine/    Not Listed.....  Not depleted;    Resident-        Small..........  Income.........  Fast...........  Fishery          No.............  No.............  Yes: Small and   N/A............  Unk............      649       142.4
                                Bay of Fundy.                      Not strategic.   nomadic.                                                            interaction,                                       resident
                                                                                                                                                        ocean noise,                                       population
                                                                                                                                                        climate change.                                    (n=1).
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: N/A = Not Applicable; Unk = Unknown.


[[Page 20059]]

    As shown in table 89, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment is 147 and 87,119, respectively. No mortality is anticipated 
or proposed for authorization, and nor is any non-auditory injury. The 
total take allowable across all 7 years of the rule is indicated in 
table 49.
    Regarding the potential takes associated with auditory impairment, 
as VHF cetaceans, harbor porpoises are more susceptible to auditory 
impacts in mid- to high frequencies and from explosives than other 
species. As described in the Temporary Threshold Shift section above, 
any takes in the form of TTS are expected to be lower-level, of short 
duration (even the longest recovering in less than a day), and mostly 
not in a frequency band that would be expected to interfere with 
porpoise communication or other important auditory cues. Any associated 
lost opportunities or capabilities individuals might experience as a 
result of TTS would not be at a level or duration that would be 
expected to impact reproductive success or survival. For similar 
reasons, while auditory injury impacts last longer, the low anticipated 
levels of AUD INJ that could be reasonably expected to result from 
these activities are unlikely to have any effect on fitness.
    Harbor porpoises are more susceptible to behavioral disturbance 
than other species. They are highly sensitive to many sound sources and 
generally demonstrate strong avoidance of most types of acoustic 
stressors. The information currently available regarding harbor 
porpoises suggests a very low threshold level of response for both 
captive (Kastelein et al., 2000; Kastelein et al., 2005) and wild 
(Johnston, 2002) animals. Southall et al. (2007) concluded that harbor 
porpoises are likely sensitive to a wide range of anthropogenic sounds 
at low received levels (approximately 90 to 120 dB). Research and 
observations of harbor porpoises for other locations show that this 
species is wary of human activity and will display profound avoidance 
behavior for anthropogenic sound sources in many situations at levels 
down to 120 dB re: 1 [micro]Pa (Southall, 2007). Harbor porpoises 
routinely avoid and swim away from large motorized vessels (Barlow et 
al., 1988; Evans et al., 1994; Palka and Hammond, 2001; Polacheck and 
Thorpe, 1990). Accordingly, and as described in the Estimated Take of 
Marine Mammals section, the threshold for behavioral disturbance is 
lower for harbor porpoises, and the number of estimated takes is 
higher, with many occurring at lower received levels than other taxa. 
Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 154 dB SPL and last from a 
few minutes to a few hours, at most. Associated responses would likely 
include avoidance, foraging interruptions, vocalization changes, or 
disruption of other social behaviors, lasting from a few minutes to 
several hours and not likely to exceed 24 hours.
    As small odontocetes and income breeders with a fast pace of life, 
harbor porpoises are less resilient to missed foraging opportunities 
than larger odontocetes. Although reproduction in populations with a 
fast pace of life are more sensitive to foraging disruption, these 
populations are quick to recover. Further, as described in the Group 
and Species-Specific Analyses section above and the Proposed Mitigation 
Measures section, mitigation measures are expected to further reduce 
the potential severity of impacts through real-time operational 
measures that minimize higher level/longer duration exposures and time/
area measures that reduce impacts in high value habitat.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. In this case, given the 
number of takes by harassment as compared to the stock/species 
abundance (see table 89), the small resident population and 
concentration of takes (85 percent) in the Northeast, it is likely that 
some portion of the individuals taken are taken repeatedly over a small 
number of days. However, given the variety of activity types that 
contribute to take across separate exercises conducted at different 
times and in different areas, and the fact that many result from 
transient activities conducted at sea, it is unlikely that repeated 
takes would occur either in numbers or clumped across sequential days 
in a manner likely to impact foraging success and energetics or other 
behaviors such that reproduction or survival of any individuals is are 
likely to be impacted.
    Given the magnitude and severity of the impacts discussed above to 
harbor porpoises (considering annual take maxima and the total across 
seven years) and their habitat, and in consideration of the required 
mitigation measures and other information presented, the Action 
Proponents' activities are unlikely to result in impacts on the 
reproduction or survival of any individuals and, thereby, unlikely to 
affect annual rates of recruitment or survival. For these reasons, we 
have determined that the take by harassment anticipated and proposed 
for authorization would have a negligible impact on the Gulf of Maine/
Bay of Fundy stock of harbor porpoises.
Pinnipeds
    This section builds on the broader discussion above and brings 
together the discussion of the different types and amounts of take that 
different stocks will incur, the applicable mitigation for each stock, 
and the status and life history of the stocks to support the negligible 
impact determinations for each stock. We have already described above 
why we believe the incremental addition of the small number of low-
level auditory injury takes will not have any meaningful effect towards 
inhibiting reproduction or survival. We have also described above in 
this section the unlikelihood of any masking or habitat impacts having 
effects that would impact the reproduction or survival of any of the 
individual marine mammals affected by the Action Proponents' 
activities. For pinnipeds, there is no predicted non-auditory injury 
from explosives for any stock, and no predicted mortality for any 
stock. Regarding the severity of individual takes by Level B harassment 
by behavioral disturbance for pinnipeds, the majority of these 
responses are anticipated to occur at received levels below 172 dB, and 
last from a few minutes to a few hours, at most, with associated 
responses most likely in the form of moving away from the source, 
foraging interruptions, vocalization changes, or disruption of other 
social behaviors, lasting from a few minutes to several hours. Because 
of the small magnitude and severity of effects for all of the species, 
it is not necessary to break out the findings by species or stock.
    In table 91 below for pinnipeds, we indicate the total annual 
mortality, Level A harassment, and Level B harassment, and a number 
indicating the instances of total take as a percentage of abundance. In 
table 92 below, we indicate the status, life history traits, important 
habitats, and threats that inform our analysis of the potential impacts 
of the estimated take on the affected pinniped stocks.
    Gray seal, harbor seal, harp seal, and hooded seal are not listed 
as endangered or threatened under the ESA, and these stocks are not 
considered depleted or strategic under the MMPA. The

[[Page 20060]]

abundance estimates for both Western North Atlantic gray seals and 
harbor seals are 27,911 and 61,336, but both of those estimates are for 
the U.S. portion of the stock only, while each stock's range extends 
into Canada. The estimated abundance of Western North Atlantic harp 
seals is 7,600,600, and a current abundance estimate for hooded seals 
is not available, though the most recent SAR (2018; Hayes et al., 2019) 
estimated an abundance of 593,500 individuals. The range of both harp 
seals and hooded seals also extends into Canada. In 2018, NMFS declared 
a UME affecting both gray seals and harbor seals (Northeast Pinniped 
UME, see Unusual Mortality Events section), but the UME is currently 
non-active and pending closure, with infectious disease determined to 
be the cause of the UME. The only known important areas for pinnipeds 
in the AFTT Study Area are known gray whale pupping areas on Green 
Island, Maine; Seal Island, Maine; and Muskeget Island, Maine. 
Pinnipeds in the AFTT Study Area face several chronic anthropogenic and 
non-anthropogenic risk factors, including entanglement, disease, and 
climate change, among others.

[[Page 20061]]



                      Table 91--Annual Estimated Take by Level B Harassment, Level A Harassment, and Mortality and Related Information for Pinnipeds in the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                Maximum
                                                                                                                                annual
                                                                               Maximum      Maximum     Maximum    Maximum    harassment                    Season(s) with 40  Region(s) with 40
     Marine mammal species              Stock        NMFS stock     NMSDD       annual       annual      annual     annual        as           Take in       percent of take    percent of take
                                                      abundance   abundance    Level B      Level A    mortality     take     percentage   important areas      or greater         or greater
                                                                              harassment   harassment                          of stock
                                                                                                                               abundance
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Gray seal......................  Western North         * 27,911      24,717       15,724           24          0     15,748            56  No.............  Winter (44         Northeast (72
                                  Atlantic.                                                                                                                  percent).          percent).
Harbor seal....................  Western North         * 61,336      10,184       22,094           32          0     22,126            36  No.............  Winter (47         Northeast (69
                                  Atlantic.                                                                                                                  percent).          percent).
Harp seal......................  Western North                *      10,007       25,792            6          0     25,798             0  No.............  N/A..............  Northeast (100
                                  Atlantic.           7,600,000                                                                                                                 percent).
Hooded seal....................  Western North            * Unk       1,097        1,726            2          0      1,728           Unk  No.............  N/A..............  Northeast (100
                                  Atlantic.                                                                                                                                     percent).
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Unk = Unknown, N/A = Not Applicable. NMSDD abundances are averages only within the U.S. EEZ.
* Indicates which abundance estimate was used to calculate the maximum annual take as a percentage of abundance, either the NMFS SAR (Hayes et al., 2024) or the NMSDD (table 2.4-1 in appendix
  A of the application). Please refer to the following section for details on which abundance estimate was selected.


                                                                                                            Table 92--Life History Traits, Important Habitat, and Threats to Pinnipeds in the AFTT Study Area
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                                                                                                                                                                                                Annual
                                                                                                                                        Reproductive                            Chronic risk       UME, oil spill,     ESA-designated     BIAs (LaBrecque    Other important                                  mortality/
     Marine mammal species              Stock            ESA status          MMPA status      Movement ecology        Body size           strategy          Pace of life           factors              other         critical habitat      et al. 2015)         habitat        Population trend      PBR       serious
                                                                                                                                                                                                                                                                                                                injury
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Gray seal......................  Western North       Not Listed........  Not Depleted......  Nomadic-migratory.  Small.............  Capital...........  Fast..............  Entanglement,       UME (declared       No................  No...............  Pupping: Green     Increasing.......         756       4,491
                                  Atlantic.                              Not Strategic.....                                                                                   illegal take/       2018, pending                                              Island, ME; Seal
                                                                                                                                                                              killing, chemical   closure).                                                  Island, ME;
                                                                                                                                                                              contaminants, oil                                                              Muskeget Island,
                                                                                                                                                                              spills and energy                                                              MA.
                                                                                                                                                                              exploration,
                                                                                                                                                                              vessel strike/
                                                                                                                                                                              interaction,
                                                                                                                                                                              disease, climate
                                                                                                                                                                              change.
Harbor seal....................  Western North       Not Listed........  Not Depleted......  Nomadic-migratory.  Small.............  Capital...........  Fast..............  Entanglement,       UME (declared       No................  No...............  None identified..  Stable/decline...       1,729         339
                                  Atlantic.                              Not Strategic.....                                                                                   illegal feeding/    2018, pending
                                                                                                                                                                              harassment,         closure).
                                                                                                                                                                              habitat
                                                                                                                                                                              degradation,
                                                                                                                                                                              vessel strike,
                                                                                                                                                                              chemical
                                                                                                                                                                              contaminants,
                                                                                                                                                                              disease, climate
                                                                                                                                                                              change.
Harp seal......................  Western North       Not Listed........  Not Depleted......  Migratory.........  Small.............  Capital...........  Fast..............  Hunting, vessel     No................  No................  No...............  None identified..  Increasing.......     426,000     178,573
                                  Atlantic.                              Not Strategic.....                                                                                   strike,
                                                                                                                                                                              entanglement,
                                                                                                                                                                              pollution, oil
                                                                                                                                                                              spills/energy
                                                                                                                                                                              exploration,
                                                                                                                                                                              climate change,
                                                                                                                                                                              prey limitations.

[[Page 20062]]

 
Hooded seal....................  Western North       Not Listed........  Not Depleted......  Migratory.........  Small.............  Capital...........  Fast..............  Vessel strike,      No................  No................  No...............  Three breeding     Increasing.......         Unk       1,680
                                  Atlantic.                              Not Strategic.....                                                                                   habitat loss,                                                                  areas in Canada.
                                                                                                                                                                              entanglement,
                                                                                                                                                                              harassment,
                                                                                                                                                                              harmful algal
                                                                                                                                                                              blooms, climate
                                                                                                                                                                              change.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Unk = Unknown.


[[Page 20063]]

    As shown in table 91, the maximum annual allowable instances of 
take under this proposed rule by Level A Harassment and Level B 
harassment range from 2 (hooded seal) to 32 (harbor seal) and 1,726 
(hooded seal) to 25,792 (harp seal), respectively. No mortality is 
anticipated or proposed for authorization, and nor is any non-auditory 
injury. The total take allowable across all 7 years of the rule for 
each stock is indicated in table 49.
    Regarding the potential takes associated with auditory impairment, 
as described above, any takes in the form of TTS are expected to be 
lower-level, of short duration, and mostly not in a frequency band that 
would be expected to interfere with pinniped communication or other 
important low-frequency cues. Any associated lost opportunities or 
capabilities individuals might experience as a result of TTS would not 
be at a level or duration that would be expected to impact reproductive 
success or survival. For similar reasons, while auditory injury impacts 
last longer, the low anticipated levels of AUD INJ that could be 
reasonably expected to result from these activities are unlikely to 
have any effect on fitness.
    Regarding the likely severity of any single instance of take by 
behavioral disturbance, as described above, the majority of the 
predicted exposures are expected to be below 172 dB SPL and last from a 
few minutes to a few hours, at most, with associated responses most 
likely in the form of moving away from the source, increased swimming 
speeds, increased surfacing time, or foraging interruptions, lasting 
from a few minutes to several hours. Pinnipeds have a fast pace of 
life, but have a relatively lower energy requirement for their body 
size, which may moderate any impact due to foraging disruption. 
However, of note, harp seals have a large inter-annual variability in 
reproductive rates due to variations in prey abundance (rely primarily 
on capelin as their preferred prey) and mid-winter ice coverage and may 
not reproduce as quickly as other pinnipeds. Also of note, gray seals 
are likely to be exposed to Navy noise sources when in their more 
southern habitats in the northeast region, especially in colder months 
when they breed and give birth.
    As described above, in addition to evaluating the anticipated 
impacts of the single instances of takes, it is important to understand 
the degree to which individual marine mammals may be disturbed 
repeatedly across multiple days of the year. For gray seals and harbor 
seals the SARs do not provide stock abundances that reflect the full 
ranges of the stocks. For hooded seals, the SAR does not provide an up-
to-date abundance estimate for any portion of the stock's range. The 
Navy's NMSDD abundance estimate for hooded seals was 1,097; however, 
this estimate appears to be underestimated by several orders of 
magnitude, as the most recent SAR estimate (2018 SAR; Hayes et al. 
2019) was 593,500 animals. For all pinniped species, given the lower 
number of takes by harassment as compared to the stock/species 
abundance (accounting for the factors described above regarding 
abundance estimates; see table 91), and their migratory or nomadic-
migratory movement patterns, it is unlikely that any individual 
pinnipeds would be taken on more than a small number of days within a 
year and, therefore, the anticipated behavioral disturbance is not 
expected to affect reproduction or survival.
    Given the magnitude and severity of the impacts discussed above 
(considering annual maxima and across 7 years) and in consideration of 
the required mitigation measures and other information presented, for 
each pinniped stock, the Action Proponents' activities are not expected 
to result in impacts on the reproduction or survival of any 
individuals, much less affect annual rates of recruitment or survival. 
Last, we have both considered the effects of the Northeast Pinniped 
UME, pending closure, in our analysis and findings regarding the impact 
of the activity on these stocks and also determined that we do not 
expect the proposed take to exacerbate the effects of the UME or 
otherwise impact the populations. For these reasons, we have determined 
that the take by harassment anticipated and to be authorized would have 
a negligible impact on all pinniped stocks.

Preliminary Determination

    Based on the analysis contained herein of the likely effects of the 
specified activities on marine mammals and their habitat, and taking 
into consideration the implementation of the proposed monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take from the specified activity will have a negligible impact 
on all affected marine mammal species or stocks.

Unmitigable Adverse Impact Analysis and Determination

    There are no relevant subsistence uses of the affected marine 
mammal stocks or species implicated by this action. Therefore, NMFS has 
determined that the total taking of affected species or stocks would 
not have an unmitigable adverse impact on the availability of such 
species or stocks for taking for subsistence purposes.

Classification

Endangered Species Act

    There are six marine mammal species under NMFS jurisdiction that 
are listed as endangered or threatened under the ESA with confirmed or 
possible occurrence in the AFTT Study Area: blue whale, fin whale, 
NARW, Rice's whale, sei whale, and sperm whale. The NARW has critical 
habitat designated under the ESA in the AFTT Study Area (81 FR 4837, 
February 26, 2016) and the Rice's whale has proposed critical habitat 
in the AFTT Study Area (88 FR 47453, July 24, 2023).
    The Action Proponents will consult with NMFS pursuant to section 7 
of the ESA for the AFTT Study Area activities. NMFS will also consult 
internally on the issuance of the regulations and three LOAs under 
section 101(a)(5)(A) of the MMPA.

National Marine Sanctuaries Act

    The Action Proponents and NMFS will work with NOAA's Office of 
National Marine Sanctuaries to fulfill our responsibilities under the 
National Marine Sanctuaries Act as warranted and will complete any NMSA 
requirements prior to a determination on the issuance of the final rule 
and LOAs.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our proposed actions with respect to potential impacts 
on the human environment. Accordingly, NMFS plans to adopt the 2024 
AFTT Draft Supplemental EIS/OEIS for the AFTT Study Area, provided our 
independent evaluation of the document finds that it includes adequate 
information analyzing the effects on the human environment of issuing 
regulations and LOAs under the MMPA. NMFS is a cooperating agency on 
the 2024 AFTT Draft Supplemental EIS/OEIS and has worked extensively 
with the Navy in developing the document. The 2024 AFTT Draft 
Supplemental EIS/OEIS was made available for public comment at https://www.nepa.navy.mil/aftteis/, which also provides additional information 
about the NEPA process, from September 20, 2024, to November 21, 2024. 
We will review all comments

[[Page 20064]]

prior to concluding our NEPA process and making a final decision on the 
MMPA rulemaking and request for LOAs.
    We will review all comments submitted in response to this notice 
prior to concluding our NEPA process or making a final decision on the 
MMPA rule and request for LOAs.

Regulatory Flexibility Act

    The Office of Management and Budget has determined that this 
proposed rule is not significant for purposes of Executive Order 12866. 
Pursuant to the Regulatory Flexibility Act (RFA), the Chief Counsel for 
Regulation of the Department of Commerce has certified to the Chief 
Counsel for Advocacy of the Small Business Administration that this 
proposed rule, if adopted, would not have a significant economic impact 
on a substantial number of small entities. The RFA requires Federal 
agencies to prepare an analysis of a rule's impact on small entities 
whenever the agency is required to publish a notice of proposed 
rulemaking. However, a Federal agency may certify, pursuant to 5 U.S.C. 
605(b), that the action will not have a significant economic impact on 
a substantial number of small entities. The Action Proponents are the 
only entities that would be affected by this rulemaking, and the Action 
Proponents are not a small governmental jurisdiction, small 
organization, or small business, as defined by the RFA. Any 
requirements imposed by an LOA issued pursuant to these regulations, 
and any monitoring or reporting requirements imposed by these 
regulations, would be applicable only to the Action Proponents. NMFS 
does not expect the issuance of these regulations or the associated 
LOAs to result in any impacts to small entities pursuant to the RFA. 
Because this action, if adopted, would directly affect only the Action 
Proponents and not any small entities, NMFS concludes that the action 
would not result in a significant economic impact on a substantial 
number of small entities.

List of Subjects in 50 CFR Part 218

    Administrative practice and procedure, Endangered and threatened 
species, Fish, Fisheries, Marine mammals, Penalties, Reporting and 
recordkeeping requirements, Transportation, Wildlife.

    Dated: April 30, 2025.
Samuel D. Rauch III,
Deputy Assistant Administrator for Regulatory Programs, National Marine 
Fisheries Service.

    For reasons set forth in the preamble, NMFS proposes to amend 50 
CFR part 218 as follows:

PART 218--REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE 
MAMMALS

0
1. The authority citation for part 218 continues to read as follows:

    Authority:  16 U.S.C. 1361 et seq.

0
2. Revise subpart I of part 218 to read as follows:

Subpart I--Taking and Importing Marine Mammals; Military Readiness 
Activities in the Atlantic Fleet Training and Testing Study Area

Sec.
218.80 Specified activity and geographical region.
218.81 Effective dates.
218.82 Permissible methods of taking.
218.83 Prohibitions.
218.84 Mitigation requirements.
218.85 Requirements for monitoring and reporting.
218.86 Letters of Authorization.
218.87 Modifications of Letters of Authorization. 218.88-218.89 
[Reserved]

Subpart I--Taking and Importing Marine Mammals; Military Readiness 
Activities in the Atlantic Fleet Training and Testing Study Area


Sec.  218.80  Specified activity and geographical region.

    (a) Regulations in this subpart apply only to the U.S. Navy (Navy) 
and U.S. Coast Guard (Coast Guard) (collectively referred to as the 
``Action Proponents'') for the taking of marine mammals that occurs in 
the area described in paragraph (b) of this section and that occurs 
incidental to the activities listed in paragraph (c) of this section.
    (b) The taking of marine mammals by the Action Proponents under 
this subpart may be authorized in Letters of Authorization (LOAs) only 
if it occurs within the Atlantic Fleet Training and Testing (AFTT) 
Study Area. The AFTT Study Area includes areas of the western Atlantic 
Ocean along the east coast of North America, the Gulf of America, and 
portions of the Caribbean Sea, covering approximately 2.6 million 
nmi\2\ (8.9 million km\2\) of ocean, oriented from the mean high tide 
line along the U.S. coast and extending east to 45[deg] W longitude 
line, north to 65[deg] N latitude line, and south to approximately the 
20[deg] N latitude line. It also includes Navy and Coast Guard pierside 
locations, port transit channels, bays, harbors, inshore waterways 
(e.g., channels, rivers), civilian ports where military readiness 
activities occur, and vessel and aircraft transit routes among 
homeports, designated operating areas (OPAREAs), and testing and 
training ranges.
    (c) The taking of marine mammals by the Action Proponents is only 
authorized if it occurs incidental to the Action Proponents conducting 
training and testing activities, including the following:
    (1) Amphibious warfare;
    (2) Anti-submarine warfare;
    (3) Expeditionary warfare;
    (4) Mine warfare;
    (5) Surface warfare;
    (6) Vessel evaluation;
    (7) Unmanned systems;
    (8) Acoustic and oceanographic science and technology;
    (9) Vessel movement; and
    (10) Other training and testing activities.


Sec.  218.81  Effective dates.

    Regulations in this subpart are effective from November 14, 2025, 
through November 13, 2032.


Sec.  218.82  Permissible methods of taking.

    (a) Under LOAs issued pursuant to Sec. Sec.  216.106 of this 
chapter and 218.87, the Holder of the LOAs (hereinafter ``Action 
Proponents'') may incidentally, but not intentionally, take marine 
mammals within the area described in Sec.  218.80(b) by Level A 
harassment and Level B harassment associated with the use of active 
sonar and other acoustic sources and explosives, as well as serious 
injury or mortality associated with vessel strikes and explosives, 
provided the activity is in compliance with all terms, conditions, and 
requirements of this subpart and the applicable LOAs.
    (b) The incidental take of marine mammals by the activities listed 
in Sec.  218.80(c) is limited to the following species:

[[Page 20065]]



                        Table 1 to Paragraph (b)
------------------------------------------------------------------------
                Species                               Stock
------------------------------------------------------------------------
North Atlantic right whale.............  Western.
Blue whale.............................  Western North Atlantic.
Bryde's whale..........................  Primary.
Fin whale..............................  Western North Atlantic.
Humpback whale.........................  Gulf of Maine.
Minke whale............................  Canadian Eastern Coast.
Rice's whale...........................  Northern Gulf of America.
Sei whale..............................  Nova Scotia.
Sperm whale............................  North Atlantic.
Sperm whale............................  Northern Gulf of America.
Dwarf sperm whale......................  Northern Gulf of America.
Pygmy sperm whale......................  Northern Gulf of America.
Dwarf sperm whale......................  Western North Atlantic.
Pygmy sperm whale......................  Western North Atlantic.
Blainville's beaked whale..............  Northern Gulf of America.
Goose-beaked whale.....................  Northern Gulf of America.
Gervais' beaked whale..................  Northern Gulf of America.
Blainville's beaked whale..............  Western North Atlantic.
Goose-beaked whale.....................  Western North Atlantic.
Gervais' beaked whale..................  Western North Atlantic.
Northern bottlenose whale..............  Western North Atlantic.
Sowerby's beaked whale.................  Western North Atlantic.
True's beaked whale....................  Western North Atlantic.
Atlantic spotted dolphin...............  Northern Gulf of America.
Bottlenose dolphin.....................  Gulf of America Eastern
                                          Coastal.
Bottlenose dolphin.....................  Gulf of America Northern
                                          Coastal.
Bottlenose dolphin.....................  Gulf of America, Oceanic.
Bottlenose dolphin.....................  Gulf of America Western
                                          Coastal.
Bottlenose dolphin.....................  Mississippi Sound, Lake Borgne,
                                          and Bay Boudreau.
Bottlenose dolphin.....................  Northern Gulf of America
                                          Continental Shelf.
Bottlenose dolphin.....................  Nueces and Corpus Christi Bays.
Bottlenose dolphin.....................  Sabine Lake.
Bottlenose dolphin.....................  St. Andrew Bay.
Bottlenose dolphin.....................  St. Joseph Bay.
Bottlenose dolphin.....................  Tampa Bay.
Clymene dolphin........................  Northern Gulf of America.
False killer whale.....................  Northern Gulf of America.
Fraser's dolphin.......................  Northern Gulf of America.
Killer whale...........................  Northern Gulf of America.
Melon-headed whale.....................  Northern Gulf of America.
Pygmy killer whale.....................  Northern Gulf of America.
Risso's dolphin........................  Northern Gulf of America.
Rough-toothed dolphin..................  Northern Gulf of America.
Short-finned pilot whale...............  Northern Gulf of America.
Striped dolphin........................  Northern Gulf of America.
Pantropical spotted dolphin............  Northern Gulf of America.
Spinner dolphin........................  Northern Gulf of America.
Atlantic white-sided dolphin...........  Western North Atlantic.
Common dolphin.........................  Western North Atlantic.
Atlantic spotted dolphin...............  Western North Atlantic.
Bottlenose dolphin.....................  Indian River Lagoon Estuarine
                                          System.
Bottlenose dolphin.....................  Jacksonville Estuarine System.
Bottlenose dolphin.....................  Northern Georgia/Southern South
                                          Carolina Estuarine System.
Bottlenose dolphin.....................  Northern North Carolina
                                          Estuarine System.
Bottlenose dolphin.....................  Southern Georgia Estuarine
                                          System.
Bottlenose dolphin.....................  Southern North Carolina
                                          Estuarine System.
Tamanend's bottlenose dolphin..........  Western North Atlantic Central
                                          Florida Coastal.
Tamanend's bottlenose dolphin..........  Western North Atlantic Northern
                                          Florida Coastal.
Bottlenose dolphin.....................  Western North Atlantic Northern
                                          Migratory Coastal.
Bottlenose dolphin.....................  Western North Atlantic
                                          Offshore.
Tamanend's bottlenose dolphin..........  Western North Atlantic South
                                          Carolina/Georgia Coastal.
Bottlenose dolphin.....................  Western North Atlantic Southern
                                          Migratory Coastal.
Clymene dolphin........................  Western North Atlantic.
False killer whale.....................  Western North Atlantic.
Fraser's dolphin.......................  Western North Atlantic.
Killer whale...........................  Western North Atlantic.
Long-finned pilot whale................  Western North Atlantic.
Melon-headed whale.....................  Western North Atlantic.
Pantropical spotted dolphin............  Western North Atlantic.
Pygmy killer whale.....................  Western North Atlantic.
Risso's dolphin........................  Western North Atlantic.
Rough-toothed dolphin..................  Western North Atlantic.

[[Page 20066]]

 
Short-finned pilot whale...............  Western North Atlantic.
Spinner dolphin........................  Western North Atlantic.
Striped dolphin........................  Western North Atlantic.
White-beaked dolphin...................  Western North Atlantic.
Harbor porpoise........................  Gulf of Maine/Bay of Fundy.
Gray seal..............................  Western North Atlantic.
Harbor seal............................  Western North Atlantic.
Harp seal..............................  Western North Atlantic.
Hooded seal............................  Western North Atlantic.
------------------------------------------------------------------------

Sec.  218.83  Prohibitions.

    (a) Except incidental take described in Sec.  218.82 and authorized 
by a LOA issued under this subpart, it shall be unlawful for any person 
to do the following in connection with the activities described in this 
subpart:
    (1) Violate, or fail to comply with, the terms, conditions, and 
requirements of this subpart or a LOA issued under Sec. Sec.  216.106 
of this chapter, 218.86, or 218.87;
    (2) Take any marine mammal not specified in Sec.  218.82(b);
    (3) Take any marine mammal specified in Sec.  218.82(b) in any 
manner other than as specified in the LOAs; or
    (4) Take a marine mammal specified in Sec.  218.82(b) after NMFS 
determines such taking results in more than a negligible impact on the 
species or stock of such marine mammal.
    (b) [Reserved]


Sec.  218.84  Mitigation requirements.

    (a) When conducting the activities identified in Sec.  218.80(c), 
the mitigation measures contained in this section and any LOA issued 
under Sec. Sec.  218.86 or 218.87 must be implemented by Action 
Proponent personnel or contractors who are trained according to the 
requirements in the LOA. If Action Proponent contractors are serving in 
a role similar to Action Proponent personnel, Action Proponent 
contractors must follow the mitigation applicable to Action Proponent 
personnel. These mitigation measures include, but are not limited to:
    (1) Activity-based mitigation. Activity-based mitigation is 
mitigation that the Action Proponents must implement whenever and 
wherever an applicable training or testing activity takes place within 
the AFTT Study Area. The Action Proponents must implement the 
mitigation described in paragraphs (a)(1)(i) through (a)(1)(xxi) of 
this section, except as provided in paragraph (a)(1)(xxii).
    (i) Active acoustic sources with power down and shut down 
capabilities. For active acoustic sources with power down and shutdown 
capabilities (low-frequency active sonar >=200 dB, mid-frequency active 
sonar sources that are hull mounted on a surface ship (including 
surfaced submarines), and broadband and other active acoustic sources 
>200 dB):
    (A) Mitigation zones and requirements. During active acoustic 
sources with power down and shutdown capabilities, the following 
mitigation zone requirements apply:
    (1) At 1,000 yd (914.4 m) from a marine mammal, Action Proponent 
personnel must power down active acoustic sources by 6 decibels (dB) 
total.
    (2) At 500 yd (457.2 m) from a marine mammal, Action Proponent 
personnel must power down active acoustic sources by 10 dB total.
    (3) At 200 yd (182.9 m) from a marine mammal, Action Proponent 
personnel must shut down active acoustic sources.
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout in or on one of the following: aircraft; pierside, 
moored, or anchored vessel; underway vessel with space/crew 
restrictions (including small boats); or underway vessel already 
participating in the event that is escorting (and has positive control 
over sources used, deployed, or towed by) an unmanned platform.
    (2) Two Lookouts on an underway vessel without space or crew 
restrictions.
    (3) Lookouts must use information from passive acoustic detections 
to inform visual observations when passive acoustic devices are already 
being used in the event.
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals and floating vegetation immediately 
prior to the initial start of using active acoustic sources (e.g., 
while maneuvering on station).
    (2) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals during use of active acoustic 
sources.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing or powering up active sonar transmission). The wait period 
for this activity is 30 minutes for activities conducted from vessels 
and for activities conducted by aircraft that are not fuel constrained 
and 10 minutes for activities involving aircraft that are fuel 
constrained (e.g., rotary-wing aircraft, fighter aircraft).
    (ii) Active acoustic sources with shut down capabilities only (no 
power down capability). For active acoustic sources with shut down 
capabilities only (no power down capability) (low-frequency active 
sonar <200 dB, mid-frequency active sonar sources that are not hull 
mounted on a surface ship (e.g., dipping sonar, towed arrays), high-
frequency active sonar, air guns, and broadband and other active 
acoustic sources <200 dB):
    (A) Mitigation zones and requirements. During use of active 
acoustic sources with shut down capabilities only, the following 
mitigation zone requirements apply:
    (1) At 200 yd (182.9 m) from a marine mammal, Action Proponent 
personnel must shut down active acoustic sources.
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout in or on one of the following: aircraft; pierside, 
moored, or anchored vessel; underway vessel with space/crew 
restrictions (including small boats); or underway vessel already 
participating in the event that is escorting (and has positive control 
over sources used, deployed, or towed by) an unmanned platform.
    (2) Two Lookouts on an underway vessel without space or crew 
restrictions.
    (3) Lookouts must use information from passive acoustic detections 
to

[[Page 20067]]

inform visual observations when passive acoustic devices are already 
being used in the event.
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals and floating vegetation immediately 
prior to the initial start of using active acoustic sources (e.g., 
while maneuvering on station).
    (2) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals during use of active acoustic 
sources.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing or powering up active sonar transmission. The wait period 
for this activity is 30 minutes for activities conducted from vessels 
and for activities conducted by aircraft that are not fuel constrained 
and 10 minutes for activities involving aircraft that are fuel 
constrained (e.g., rotary-wing aircraft, fighter aircraft).
    (iii) Pile driving and extraction. For pile driving and extraction:
    (A) Mitigation zones and requirements. During vibratory and impact 
pile driving and extraction, the following mitigation zone requirements 
apply:
    (1) Action Proponent personnel must cease pile driving or 
extraction if a marine mammal is sighted within 100 yd (91.4 m) of a 
pile being driven or extracted.
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout in or on one of the following: shore, pier, or 
small boat.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals and floating vegetation for 15 minutes prior to the 
initial start of pile driving or pile extraction.
    (2) Action Proponent personnel must observe the mitigation zone for 
marine mammals during pile driving or extraction.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing vibratory and impact pile driving and extraction). The 
wait period for this activity is 15 minutes.
    (iv) Weapons firing noise. For weapons firing noise:
    (A) Mitigation zones and requirements. During explosive and non-
explosive large-caliber gunnery firing noise (surface-to-surface and 
surface-to-air), the following mitigation zone requirements apply:
    (1) Action Proponent personnel must cease weapons firing if a 
marine mammal is sighted within 30 degrees on either side of the firing 
line out to 70 yd (64 m) from the gun muzzle (cease fire).
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout on a vessel.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals and floating vegetation immediately prior to the initial 
start of large-caliber gun firing (e.g., during target deployment).
    (2) Action Proponent personnel must observe the mitigation zone for 
marine mammals during large-caliber gun firing.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing explosive and non-explosive large-caliber gunnery firing 
noise (surface-to-surface and surface-to-air)). The wait period for 
this activity is 30 minutes.
    (v) Explosive bombs. For explosive bombs:
    (A) Mitigation zones and requirements. During the use of explosive 
bombs of any net explosive weight (NEW), the following mitigation zone 
requirements apply:
    (1) Action Proponent personnel must cease explosive bomb use if a 
marine mammal is sighted within 2,500 yd (2,286 m) from the intended 
target.
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout in an aircraft.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals and floating vegetation immediately 
prior to the initial start of bomb delivery (e.g., when arriving on 
station).
    (2) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals during bomb delivery.
    (3) After the event, when practical, Action Proponent personnel 
must observe the detonation vicinity for injured or dead marine 
mammals. If any injured or dead marine mammals are observed, Action 
Proponent personnel must follow established incident reporting 
procedures.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing use of explosive bombs of any NEW). The wait period for 
this activity is 10 minutes.
    (vi) Explosive gunnery. For explosive gunnery:
    (A) Mitigation zones and requirements. During air-to-surface 
medium-caliber, surface-to-surface medium-caliber, surface-to-surface 
large-caliber explosive gunnery, the following mitigation zone 
requirements apply:
    (1) Action Proponent personnel must cease air-to-surface medium-
caliber use if a marine mammal is sighted within 200 yd (182.9 m) of 
the intended impact location.
    (2) Action Proponent personnel must cease surface-to-surface 
medium-caliber use if a marine mammal is sighted within 600 yd (548.6 
m) of the intended impact location.
    (3) Action Proponent personnel must cease surface-to-surface large-
caliber use if a marine mammal is sighted within 1,000 yd (914.4 m) of 
the intended impact location.
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout on a vessel or in an aircraft.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals and floating vegetation immediately 
prior to the initial start of gun firing (e.g., while maneuvering on 
station).

[[Page 20068]]

    (2) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals during gunnery fire.
    (3) After the event, when practical, Action Proponent personnel 
must observe the detonation vicinity for injured or dead marine 
mammals. If any injured or dead marine mammals are observed, Action 
Proponent personnel must follow established incident reporting 
procedures.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing air-to-surface medium-caliber, surface-to-surface medium-
caliber, surface-to-surface large-caliber explosive gunnery). The wait 
period for this activity is 30 minutes for activities conducted from 
vessels and for activities conducted by aircraft that are not fuel 
constrained and 10 minutes for activities involving aircraft that are 
fuel constrained (e.g., rotary-wing aircraft, fighter aircraft).
    (vii) Explosive line charges. For explosive line charges:
    (A) Mitigation zones and requirements. During the use of explosive 
line charges of any NEW, the following mitigation zone requirements 
apply:
    (1) Action Proponent personnel must cease explosive line charges if 
a marine mammal is sighted within 900 yd (823 m) of the detonation 
site.
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout on a vessel.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals and floating vegetation immediately prior to the initial 
start of detonations (e.g., while maneuvering on station).
    (2) Action Proponent personnel must observe the mitigation zone for 
marine mammals during detonations.
    (3) After the event, when practical, Action Proponent personnel 
must observe the detonation vicinity for injured or dead marine 
mammals. If any injured or dead marine mammals are observed, Action 
Proponent personnel must follow established incident reporting 
procedures.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing use of explosive line charges of any NEW). The wait period 
for this activity is 30 minutes.
    (viii) Explosive mine countermeasure and neutralization (no 
divers). For explosive mine countermeasure neutralization (no divers):
    (A) Mitigation zones and requirements. During explosive mine 
countermeasure and neutralization using 0.1-5 pound (lb) (0.05-2.3 
kilogram (kg)) NEW and >5 lb (2.3 kg) NEW, the following mitigation 
zone requirements apply:
    (1) Action Proponent personnel must cease 0.1-5 lb (0.05-2.3 kg) 
NEW use if a marine mammal is sighted within 600 yd (548.6 m) of 
detonation site.
    (2) Action Proponent personnel must cease >5 lb (2.3 kg) NEW use if 
a marine mammal is sighted within 2,100 yd (1,920.2 m) of the 
detonation site.
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout on a vessel or in an aircraft during 0.1-5 lb 
(0.05-2.3 kg) NEW use.
    (2) Two Lookouts: one on a small boat and one in an aircraft during 
>5 lb (2.3 kg) NEW use.
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals and floating vegetation immediately 
prior to the initial start of detonations (e.g., while maneuvering on 
station; typically, 10 or 30 minutes depending on fuel constraints).
    (2) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals during detonations or fuse 
initiation.
    (3) After the event, when practical, Action Proponent personnel 
must observe the detonation vicinity for 10 or 30 minutes (depending on 
fuel constraints) for injured or dead marine mammals. If any injured or 
dead marine mammals are observed, Action Proponent personnel must 
follow established incident reporting procedures.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing explosive mine countermeasure and neutralization using 
0.1-5 pound (lb) (0.05-2.3 kilogram (kg)) NEW and >5 lb (2.3 kg) NEW). 
The wait period for this activity is 30 minutes for activities 
conducted from vessels and for activities conducted by aircraft that 
are not fuel constrained and 10 minutes for activities involving 
aircraft that are fuel constrained (e.g., rotary-wing aircraft, fighter 
aircraft).
    (ix) Explosive mine neutralization (with divers). For explosive 
mine neutralization (with divers):
    (A) Mitigation zones and requirements. During explosive mine 
neutralization (with divers) using 0.1-20 lb (0.05-9.1 kg) NEW 
(positive control), 0.1-20 lb (0.05-9.1 kg) NEW (time-delay), and >20-
60 lb (9.1-27.2 kg) NEW (positive control), the following mitigation 
zone requirements apply:
    (1) Action Proponent personnel must cease 0.1-20 lb (0.05-9.1 kg) 
NEW (positive control) use if a marine mammal is sighted within 500 yd 
(457.2 m) of the detonation site (cease fire).
    (2) Action Proponent personnel must cease 0.1-20 lb (0.05-9.1 kg) 
NEW (time-delay) and >20-60 lb (9.1-27.2 kg) NEW (positive control) use 
if a marine mammal is sighted within 1,000 yd (914.4 m) of the 
detonation site (cease fire).
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) Two Lookouts in two small boats (one Lookout per boat) or one 
small boat and one rotary-wing aircraft (with one Lookout each) during 
0.1-20 lb (0.05-9.1 kg) NEW (positive control) use.
    (2) Four Lookouts in two small boats (two Lookouts per boat) and 
one additional Lookout in an aircraft if used in the event during 0.1-
20 lb (0.05-9.1 kg) NEW (time-delay) and >20-60 lb (9.1-27.2 kg) NEW 
(positive control) use.
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Time-delay devices must be set not to exceed 10 minutes.
    (2) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals and floating vegetation immediately 
prior to the initial start of detonations or fuse initiation for 
positive control events (e.g., while maneuvering on station) or for 30 
minutes prior for time-delay events.
    (3) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals during detonations or fuse 
initiation.

[[Page 20069]]

    (4) When practical based on mission, safety, and environmental 
conditions:
    (i) Boats must observe from the mitigation zone radius mid-point.
    (ii) When two boats are used, boats must observe from opposite 
sides of the mine location.
    (iii) Platforms must travel a circular pattern around the mine 
location.
    (iv) Boats must have one Lookout observe inward toward the mine 
location and one Lookout observe outward toward the mitigation zone 
perimeter.
    (v) Divers must be part of the Lookout Team.
    (5) After the event, when practical, Action Proponent personnel 
must observe the detonation vicinity for 30 minutes for injured or dead 
marine mammals. If any injured or dead marine mammals are observed, 
Action Proponent personnel must follow established incident reporting 
procedures.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing explosive mine neutralization (with divers) using 0.1-20 
lb (0.05-9.1 kg) NEW (positive control), 0.1-20 lb (0.05-9.1 kg) NEW 
(time-delay), and >20-60 lb (9.1-27.2 kg) NEW (positive control)). The 
wait period for this activity is 30 minutes for activities conducted 
from vessels and for activities conducted by aircraft that are not fuel 
constrained and 10 minutes for activities involving aircraft that are 
fuel constrained (e.g., rotary-wing aircraft, fighter aircraft).
    (x) Explosive missiles and rockets. For explosive missiles and 
rockets:
    (A) Mitigation zones and requirements. During the use of explosive 
missiles and rockets using 0.6-20 lb (0.3-9.1 kg) NEW (air-to-surface) 
and >20-500 lb (9.1-226.8 kg) NEW (air-to-surface), the following 
mitigation zone requirements apply:
    (1) Action Proponent personnel must cease 0.6-20 lb (0.3-9.1 kg) 
NEW (air-to-surface) use if a marine mammal is sighted within 900 yd 
(823 m) of the intended impact location (cease fire).
    (2) Action Proponent personnel must cease >20-500 lb (9.1-226.8 kg) 
NEW (air-to-surface) use if a marine mammal is sighted within 2,000 yd 
(1,828.8 m) of the intended impact location (cease fire).
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout in an aircraft.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals and floating vegetation immediately 
prior to the initial start of missile or rocket delivery (e.g., during 
a fly-over of the mitigation zone).
    (2) Action Proponent personnel must observe the applicable 
mitigation zone for marine mammals during missile or rocket delivery.
    (3) After the event, when practical, Action Proponent personnel 
must observe the detonation vicinity for injured or dead marine 
mammals. If any injured or dead marine mammals are observed, Action 
Proponent personnel must follow established incident reporting 
procedures.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing use of explosive missiles and rockets using 0.6-20 lb 
(0.3-9.1 kg) NEW (air-to-surface) and >20-500 lb (9.1-226.8 kg) NEW 
(air-to-surface)). The wait period for this activity is 30 minutes for 
activities conducted from vessels and for activities conducted by 
aircraft that are not fuel constrained and 10 minutes for activities 
involving aircraft that are fuel constrained (e.g., rotary-wing 
aircraft, fighter aircraft).
    (xi) Explosive sonobuoys and research-based sub-surface explosives. 
For explosive sonobuoys and research-based sub-surface explosives:
    (A) Mitigation zones and requirements. During the use of explosive 
sonobuoys and research-based sub-surface explosives using any NEW of 
sonobuoys and 0.1-5 lb (0.05-2.3 kg) NEW for other types of sub-surface 
explosives used in research applications, the following mitigation zone 
requirements apply:
    (1) Action Proponent personnel must cease use of explosive 
sonobuoys and research-based sub-surface explosives using any NEW of 
sonobuoys and 0.1-5 lb (0.05-2.3 kg) NEW for other types of sub-surface 
explosives used in research applications if a marine mammal is sighted 
within 600 yd (548.6 m) of the device or detonation sites (cease fire).
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout on a small boat or in an aircraft.
    (2) Conduct passive acoustic monitoring for marine mammals; use 
information from detections to assist visual observations.
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals and floating vegetation immediately prior to the initial 
start of detonations (e.g., during sonobuoy deployment, which typically 
lasts 20-30 minutes).
    (2) Action Proponent personnel must observe the mitigation zone for 
marine mammals during detonations.
    (3) After the event, when practical, Action Proponent personnel 
must observe the detonation vicinity for injured or dead marine 
mammals. If any injured or dead marine mammals are observed, Action 
Proponent personnel must follow established incident reporting 
procedures.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing use of explosive sonobuoys and research-based sub-surface 
explosives using any NEW of sonobuoys and 0.1-5 lb (0.05-2.3 kg) NEW 
for other types of sub-surface explosives used in research 
applications). The wait period for this activity is 30 minutes for 
activities conducted from vessels and for activities conducted by 
aircraft that are not fuel constrained and 10 minutes for activities 
involving aircraft that are fuel constrained (e.g., rotary-wing 
aircraft, fighter aircraft).
    (xii) Explosive torpedoes. For explosive torpedoes:
    (A) Mitigation zones and requirements. During the use of explosive 
torpedoes of any NEW, the following mitigation zone requirements apply:
    (1) Action Proponent personnel must cease use of explosive 
torpedoes of any NEW if a marine mammal is sighted within 2,100 yd 
(1,920.2 m) of the intended impact location.
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout in an aircraft.
    (2) Conduct passive acoustic monitoring for marine mammals; use 
information from detections to assist visual observations.

[[Page 20070]]

    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals, floating vegetation, and jellyfish aggregations 
immediately prior to the initial start of detonations (e.g., during 
target deployment).
    (2) Action Proponent personnel must observe the mitigation zone for 
marine mammals and jellyfish aggregations during torpedo launches.
    (3) After the event, when practical, Action Proponent personnel 
must observe the detonation vicinity for injured or dead marine 
mammals. If any injured or dead marine mammals are observed, Action 
Proponent personnel must follow established incident reporting 
procedures.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing use of explosive torpedoes of any NEW). The wait period 
for this activity is 30 minutes for activities conducted from vessels 
and for activities conducted by aircraft that are not fuel constrained 
and 10 minutes for activities involving aircraft that are fuel 
constrained (e.g., rotary-wing aircraft, fighter aircraft).
    (xiii) Ship shock trials. For ship shock trials:
    (A) Mitigation zones and requirements. During ship shock trials 
using any NEW, the following mitigation zone requirements apply:
    (1) Action Proponent personnel must cease ship shock trials of any 
NEW if a marine mammal is sighted within 3.5 nmi (6.5 km) of the target 
ship hull (cease fire).
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) On the day of the event, 10 observers (Lookouts and third-party 
observers combined), spread between aircraft or multiple vessels as 
specified in the event-specific mitigation plan.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must develop a detailed, event-
specific monitoring and mitigation plan in the year prior to the event 
and provide it to NMFS for review.
    (2) Beginning at first light on days of detonation, until the 
moment of detonation (as allowed by safety measures) Action Proponent 
personnel must observe the mitigation zone for marine mammals, floating 
vegetation, jellyfish aggregations, large schools of fish, and flocks 
of seabirds.
    (3) If any dead or injured marine mammals are observed after an 
individual detonation, Action Proponent personnel must follow 
established incident reporting procedures and halt any remaining 
detonations until Action Proponent personnel or third-party observers 
can consult with NMFS and review or adapt the event-specific mitigation 
plan, if necessary.
    (4) During the 2 days following the event (minimum) and up to 7 
days following the event (maximum), and as specified in the event-
specific mitigation plan, Action Proponent personnel must observe the 
detonation vicinity for injured or dead marine mammals.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing ship shock trials). The wait period for this activity is 
30 minutes.
    (xiv) Sinking Exercises. For Sinking Exercises (SINKEX):
    (A) Mitigation zones and requirements. During SINKEX using any NEW, 
the following mitigation zone requirements apply:
    (1) Action Proponent personnel must cease SINKEX of any NEW if a 
marine mammal is sighted within 2.5 nmi (4.6 km) of the target ship 
hull (cease fire).
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) Two Lookouts: one on a vessel and one in an aircraft.
    (2) Conduct passive acoustic monitoring for marine mammals; use 
information from detections to assist visual observations.
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) During aerial observations for 90 minutes prior to the initial 
start of weapon firing, Action Proponent personnel must observe the 
mitigation zone for marine mammals, floating vegetation, and jellyfish 
aggregations.
    (2) From the vessel during weapon firing, and from the aircraft and 
vessel immediately after planned or unplanned breaks in weapon firing 
of more than 2 hours, Action Proponent personnel must observe the 
mitigation zone for marine mammals.
    (3) Action Proponent personnel must observe the detonation vicinity 
for injured or dead marine mammals for 2 hours after sinking the vessel 
or until sunset, whichever comes first. If any injured or dead marine 
mammals are observed, Action Proponent personnel must follow 
established incident reporting procedures.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing SINKEX). The wait period for this activity is 30 minutes.
    (xv) Non-explosive aerial-deployed mines and bombs. For non-
explosive aerial-deployed mines and bombs:
    (A) Mitigation zones and requirements. During the use of non-
explosive aerial-deployed mines and non-explosive bombs, the following 
mitigation zone requirements apply:
    (1) Action Proponent personnel must cease using non-explosive 
aerial-deployed mines and non-explosive bombs use if a marine mammal is 
sighted within 1,000 yd (914.4 m) of the intended target (cease fire).
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout in an aircraft.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals and floating vegetation immediately prior to the initial 
start of mine or bomb delivery (e.g., when arriving on station).
    (2) Action Proponent personnel must observe the mitigation zone for 
marine mammals during mine or bomb delivery.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing use of non-explosive aerial-deployed mines and non-
explosive bombs). The wait period for this activity is 10 minutes.
    (xvi) Non-explosive gunnery. For non-explosive gunnery:
    (A) Mitigation zones and requirements. During the use of non-

[[Page 20071]]

explosive surface-to-surface large-caliber ordnance, non-explosive 
surface-to-surface and air-to-surface medium-caliber ordnance, and non-
explosive surface-to-surface and air-to-surface small-caliber ordnance, 
the following mitigation zone requirements apply:
    (1) Action Proponent personnel must cease non-explosive surface-to-
surface large-caliber ordnance, non-explosive surface-to-surface and 
air-to-surface medium-caliber ordnance, and non-explosive surface-to-
surface and air-to-surface small-caliber ordnance use if a marine 
mammal is sighted within 200 yd (182.9 m) of the intended impact 
location (cease fire).
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout on a vessel or in an aircraft.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals and floating vegetation immediately prior to the start 
of gun firing (e.g., while maneuvering on station).
    (2) Action Proponent personnel must observe the mitigation zone for 
marine mammals during gunnery firing.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing use of non-explosive surface-to-surface large-caliber 
ordnance, non-explosive surface-to-surface and air-to-surface medium-
caliber ordnance, and non-explosive surface-to-surface and air-to-
surface small-caliber ordnance). The wait period for this activity is 
30 minutes for activities conducted from vessels and for activities 
conducted by aircraft that are not fuel constrained and 10 minutes for 
activities involving aircraft that are fuel constrained (e.g., rotary-
wing aircraft, fighter aircraft).
    (xvii) Non-explosive missiles and rockets. For non-explosive 
missiles and rockets:
    (A) Mitigation zones and requirements. During the use of non-
explosive missiles and rockets (air-to-surface), the following 
mitigation zone requirements apply:
    (1) Action Proponent personnel must cease non-explosive missile and 
rocket (air-to-surface) use if a marine mammal is sighted within 900 yd 
(823 m) of the intended impact location.
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout in an aircraft.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals and floating vegetation immediately prior to the start 
of missile or rocket delivery (e.g., during a fly-over of the 
mitigation zone).
    (2) Action Proponent personnel must observe the mitigation zone for 
marine mammals during missile or rocket delivery.
    (D) Commencement or recommencement conditions. Action Proponent 
personnel must ensure one of the commencement or recommencement 
conditions in Sec.  218.84(a)(1)(xxi) is met prior to the initial start 
of the activity (by delaying the start) or during the activity (by not 
recommencing use of non-explosive missiles and rockets (air-to-
surface)). The wait period for this activity is 30 minutes for 
activities conducted from vessels and for activities conducted by 
aircraft that are not fuel constrained and 10 minutes for activities 
involving aircraft that are fuel constrained (e.g., rotary-wing 
aircraft, fighter aircraft).
    (xviii) Manned surface vessels. For manned surface vessels:
    (A) Mitigation zones and requirements. During the use of manned 
surface vessels, including surfaced submarines, the following 
mitigation zone requirements apply:
    (1) Underway manned surface vessels must maneuver themselves (which 
may include reducing speed) to maintain the following distances as 
mission and circumstances allow:
    (i) 500 yd (457.2 m) from whales.
    (ii) 200 yd (182.9 m) from other marine mammals.
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One or more Lookouts on manned underway surface vessels in 
accordance with the most recent navigation safety instruction.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals immediately prior to manned surface vessels getting 
underway and while underway.
    (2) [Reserved]
    (xix) Unmanned vehicles. For unmanned vehicles:
    (A) Mitigation zones and requirements. During the use of unmanned 
surface vehicles and unmanned underwater vehicles already being 
escorted (and operated under positive control) by a manned surface 
support vessel, the following mitigation zone requirements apply:
    (1) A surface support vessel that is already participating in the 
event, and has positive control over the unmanned vehicle, must 
maneuver the unmanned vehicle (which may include reducing its speed) to 
ensure it maintains the following distances as mission and 
circumstances allow:
    (i) 500 yd (457.2 m) from whales.
    (ii) 200 yd (182.9 m) from other marine mammals.
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout on a surface support vessel that is already 
participating in the event, and has positive control over the unmanned 
vehicle.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals immediately prior to unmanned vehicles getting underway 
and while underway.
    (2) [Reserved]
    (xx) Towed in-water devices. For towed in-water devices:
    (A) Mitigation zones and requirements. During the use of in-water 
devices towed by an aircraft, a manned surface vessel, or an Unmanned 
Surface Vehicle or Unmanned Underwater Vehicle already being escorted 
(and operated under positive control) by a crewed surface vessel, the 
following mitigation zone requirements apply:
    (1) Manned towing platforms, or surface support vessels already 
participating in the event that have positive control over an unmanned 
vehicle that is towing an in-water device, must maneuver itself or the 
unmanned vehicle (which may include reducing speed) to ensure towed in-
water devices maintain the following distances as mission and 
circumstances allow:
    (i) 250 yd (228.6 m) from marine mammals.
    (ii) [Reserved]
    (2) [Reserved]
    (B) Lookout requirements. The following Lookout requirements apply:
    (1) One Lookout on the manned towing vessel, or on a surface 
support

[[Page 20072]]

vessel that is already participating in the event and has positive 
control over an unmanned vehicle that is towing an in-water device.
    (2) [Reserved]
    (C) Mitigation zone observation. Action Proponent personnel must 
observe the mitigation zones in accordance with the following:
    (1) Action Proponent personnel must observe the mitigation zone for 
marine mammals immediately prior to and while in-water devices are 
being towed.
    (2) [Reserved]
    (xxi) Commencement or recommencement conditions. Action Proponents 
must not commence or recommence an activity after a marine mammal is 
observed within a relevant mitigation zone until one of the following 
conditions has been met:
    (A) Observed exiting. A Lookout observes the animal exiting the 
mitigation zone;
    (B) Concluded to have exited. A Lookout concludes that the animal 
has exited the mitigation zone based on its observed course, speed, and 
movement relative to the mitigation zone;
    (C) Clear from additional sightings. A Lookout affirms the 
mitigation zone has been clear from additional sightings for the 
activity-specific wait period; or
    (D) Stressor transit. For mobile events, the stressor has transited 
a distance equal to double the mitigation zone size beyond the location 
of the last sighting.
    (xxii) Exceptions to activity-based mitigation. Activity-based 
mitigation for acoustic stressors will not apply to:
    (A) Sources not operated under positive control (e.g., moored 
oceanographic sources);
    (B) Sources used for safety of navigation (e.g., fathometers);
    (C) Sources used or deployed by aircraft operating at high 
altitudes (e.g., bombs deployed from high altitude (since personnel 
cannot effectively observe the surface of the water));
    (D) Sources used, deployed, or towed by unmanned platforms except 
when escort vessels are already participating in the event and have 
positive control over the source;
    (E) Sources used by submerged submarines (e.g., sonar (since they 
cannot conduct visual observation));
    (F) De minimis sources (e.g., those >200 kHz);
    (G) Long-duration sources, including those used for acoustic and 
oceanographic research; and
    (H) Vessel-based, unmanned vehicle-based, or towed in-water sources 
when marine mammals (e.g., dolphins) are determined to be intentionally 
swimming at the bow or alongside or directly behind the vessel, 
vehicle, or device (e.g., to bow-ride or wake-ride).
    (2) Geographic mitigation areas. The Action Proponents must 
implement the geographic mitigation requirements described in 
paragraphs (a)(2)(i) through (a)(2)(viii) of this section.
    (i) Ship shock trial mitigation area. Figure 1 to this paragraph 
(a)(2) shows the location of the mitigation areas. Within the ship 
shock trial mitigation areas, the following requirements apply:
    (A) Jacksonville Operating Area. Navy personnel must not conduct 
ship shock trials within the portion of the ship shock trial box that 
overlaps the Jacksonville Operating Area from November 15 through April 
15.
    (B) Pre-event planning. Pre-event planning for ship shock trials 
must include the selection of one primary and two secondary sites 
(within one of the ship shock trial boxes) where marine mammal 
abundance is expected to be the lowest during an event, with the 
primary and secondary locations located more than 2 nmi (3.7 km) from 
the western boundary of the Gulf Stream for events planned within the 
portion of the ship shock trial box that overlaps the Jacksonville 
Operating Area.
    (C) Environmentally unsuitable site. If Action Proponent personnel 
determine during pre-event visual observations that the primary site is 
environmentally unsuitable (e.g., continuous observations of marine 
mammals), personnel must evaluate the potential to move the event to 
one of the secondary sites as described in the LOAs.
    (ii) Major training exercise planning awareness mitigation areas. 
Figure 1 to this paragraph (a)(2) shows the location of the mitigation 
area. Within the major training exercise planning awareness mitigation 
areas, the following requirements apply:
    (A) Northeast. Within Major Training Exercise Planning Awareness 
Mitigation Areas located in the Northeast (i.e., the combined areas 
within the Gulf of Maine, over the continental shelves off Long Island, 
Rhode Island, Massachusetts, and Maine), the Action Proponents must not 
conduct any full or partial Major Training Exercises (MTEs).
    (B) Mid-Atlantic. Within Major Training Exercise Planning Awareness 
Mitigation Areas located in the Mid-Atlantic (i.e., the combined areas 
off Maryland, Delaware, and North Carolina), the Action Proponents must 
not conduct any full or partial MTEs to the maximum extent practical, 
and must not conduct more than four full or partial MTEs per year.
    (iii) Northeast North Atlantic right whale mitigation area. Figure 
1 to this paragraph (a)(2) shows the location of the mitigation area. 
Within the northeast North Atlantic right whale mitigation area, the 
following requirements apply:
    (A) Active sonar. The Action Proponents must minimize the use of 
low-frequency active sonar, mid-frequency active sonar, and high-
frequency active sonar in the mitigation area to the maximum extent 
practical.
    (B) In-water explosives. The Action Proponents must not detonate 
in-water explosives (including underwater explosives and explosives 
deployed against surface targets) within the mitigation area.
    (C) Explosive sonobuoys. The Action Proponents must not detonate 
explosive sonobuoys within 3 nmi (5.6 km) of the mitigation area.
    (D) Non-explosive bombs. The Action Proponents must not use non-
explosive bombs within the mitigation area.
    (E) Non-explosive torpedoes. During non-explosive torpedoes events 
within the mitigation area:
    (1) The Action Proponents must conduct activities during daylight 
hours in Beaufort sea state 3 or less;
    (2) The Action Proponents must post two Lookouts in an aircraft 
during dedicated aerial surveys, and one Lookout on the submarine 
participating in the event (when surfaced), in addition to Lookouts 
required as described in Sec.  218.84(a)(1)(xvii).
    (i) Lookouts must begin conducting visual observations immediately 
prior to the start of an event.
    (ii) If floating vegetation or marine mammals are observed in the 
event vicinity, the event must not commence until the vicinity is clear 
or the event is relocated to an area where the vicinity is clear.
    (iii) Lookouts must continue to conduct visual observations during 
the event.
    (iv) If marine mammals are observed in the vicinity, the event must 
cease until one of the commencement or recommencement conditions in 
Sec.  218.84(a)(1)(xxi) is met.
    (3) During transits and normal firing, surface ships must maintain 
a speed of no more than 10 knots (kn; 18.5 kilometer/hour (km/hr)); 
during submarine target firing, surface ships must maintain speeds of 
no more than 18 kn (33.3 km/hr); and during vessel target firing, 
surface ship speeds may exceed 18 kn (33.3 km/hr) for brief periods of 
time (e.g., 10-15 minutes).
    (F) Vessel transits. For vessel transits within the mitigation 
area:
    (1) The Action Proponents must conduct a web query or email inquiry 
to the North Atlantic Right Whale Sighting Advisory System or WhaleMap 
(https://whalemap.org/) to obtain the latest North Atlantic right whale 
sightings

[[Page 20073]]

data prior to transiting the mitigation area.
    (2) The Action Proponents must provide Lookouts the sightings data 
prior to standing watch. Lookouts must use that data to help inform 
visual observations during vessel transits.
    (G) Speed reductions. Surface ships must implement speed reductions 
after observing a North Atlantic right whale, if transiting within 5 
nmi (9.3 km) of a sighting reported to the North Atlantic Right Whale 
Sighting Advisory System within the past week, and when transiting at 
night or during periods of reduced visibility.
    (iv) Gulf of Maine marine mammal mitigation area. Figure 1 to this 
paragraph (a)(2) shows the location of the mitigation area. Within the 
Gulf of Maine marine mammal mitigation area, the following requirements 
apply:
    (A) Surface ship hull-mounted mid-frequency active sonar. The 
Action Proponents must not use more than 200 hours of surface ship 
hull-mounted mid-frequency active sonar annually within the mitigation 
area.
    (B) [Reserved]
    (v) Jacksonville Operating Area North Atlantic right whale 
mitigation area. Figure 1 to this paragraph (a)(2) shows the location 
of the mitigation area. Within the Jacksonville Operating Area North 
Atlantic right whale mitigation area, the following requirements apply:
    (A) November 15 to April 15. From November 15 to April 15 within 
the mitigation area, prior to vessel transits or military readiness 
activities involving active sonar, in-water explosives (including 
underwater explosives and explosives deployed against surface targets), 
or non-explosive ordnance deployed against surface targets (including 
aerial-deployed mines), the Action Proponents must initiate 
communication with Fleet Area Control and Surveillance Facility, 
Jacksonville to obtain Early Warning System data. The facility must 
advise of all reported North Atlantic right whale sightings in the 
vicinity of planned vessel transits and military readiness activities. 
Sightings data must be used when planning event details (e.g., timing, 
location, duration) to minimize impacts to North Atlantic right whale 
to the maximum extent practical.
    (B) Sightings data to Lookouts. Action Proponent personnel must 
provide the sightings data to Lookouts prior to standing watch to help 
inform visual observations.
    (vi) Southeast North Atlantic right whale mitigation area. Figure 1 
to this paragraph (a)(2) shows the location of the mitigation area. 
Within the Southeast North Atlantic right whale mitigation area, the 
following requirements apply:
    (A) Helicopter dipping sonar and low-frequency or surface ship 
hull-mounted mid-frequency active sonar during navigation training or 
object detection. From November 15 to April 15 within the mitigation 
area, to the maximum extent practical, the Action Proponents must 
minimize use of helicopter dipping sonar (a mid-frequency active sonar 
source) and low-frequency or surface ship hull-mounted mid-frequency 
active sonar during navigation training or object detection.
    (B) All other high-frequency, mid-frequency, or low-frequency 
active sonars. From November 15 to April 15 within the mitigation area, 
the Action Proponents must not use high-frequency active sonar; or low-
frequency or mid-frequency active sonar with the exception of the 
sources listed in paragraph (a)(2)(vi)(A) of this section in accordance 
with that paragraph.
    (C) Explosives. From November 15 to April 15 within the mitigation 
area, the Action Proponents must not detonate in-water explosives 
(including underwater explosives and explosives deployed against 
surface targets).
    (D) Physical disturbance. From November 15 to April 15 within the 
mitigation area, the Action Proponents must not deploy non-explosive 
ordnance against surface targets (including aerial-deployed mines).
    (E) Vessel strike. From November 15 to April 15 within the 
mitigation area, surface ships must minimize north-south transits to 
the maximum extent practical, and must implement speed reductions to 
the maximum extent practicable after they observe a North Atlantic 
right whale, if they are within 5 nmi (9.3 km) of an Early Warning 
System sighting reported within the past 12 hours, and at night and in 
poor visibility.
    (F) Acoustic, explosives, and physical disturbance and vessel 
strike. From November 15 to April 15 within the mitigation area, prior 
to vessel transits or military readiness activities involving active 
sonar, in-water explosives (including underwater explosives and 
explosives deployed against surface targets), or non-explosive ordnance 
deployed against surface targets (including aerial-deployed mines), the 
Action Proponents must initiate communication with Fleet Area Control 
and Surveillance Facility, Jacksonville to obtain Early Warning System 
sightings data. The facility must advise of all reported North Atlantic 
right whale sightings in the vicinity of planned vessel transits and 
military readiness activities. The Action Proponents must provide 
Lookouts the sightings data prior to standing watch to help inform 
visual observations.
    (vii) Dynamic North Atlantic right whale mitigation areas. The 
applicable dates and locations of this mitigation area must correspond 
with NMFS' Dynamic Management Areas, which vary throughout the year 
based on the locations and timing of confirmed North Atlantic right 
whale detections. Within the Dynamic North Atlantic right whale 
mitigation areas, the following requirements apply:
    (A) North Atlantic right whale Dynamic Management Area 
notifications. The Action Proponents must provide North Atlantic right 
whale Dynamic Management Area information (e.g., location and dates) to 
applicable assets transiting and training or testing in the vicinity of 
the Dynamic Management Area. The broadcast awareness notification 
messages must alert assets (and their Lookouts) to the possible 
presence of North Atlantic right whale in their vicinity.
    (B) Visual observations. Lookouts must use the information to help 
inform visual observations during military readiness activities that 
involve vessel movements, active sonar, in-water explosives (including 
underwater explosives and explosives deployed against surface targets), 
or non-explosive ordnance deployed against surface targets in the 
mitigation area.
    (viii) Rice's whale mitigation area. Figure 1 to this paragraph 
(a)(2) shows the location of the mitigation area. Within the Rice's 
whale mitigation area, the following requirements apply:
    (A) Surface ship mid-frequency active sonar. The Action Proponents 
must not use more than 200 hours of surface ship hull-mounted mid-
frequency active sonar annually within the mitigation area.
    (B) Explosives. The Action Proponents must not detonate in-water 
explosives (including underwater explosives and explosives deployed 
against surface targets) within the mitigation area, except during mine 
warfare activities.
    (ix) National Security Requirement. Should national security 
require the Action Proponents to exceed a requirement in paragraphs 
(a)(2)(i) through (a)(2)(viii) of this section, Action Proponent 
personnel must provide NMFS with advance notification and include the 
information (e.g., sonar hours, explosives usage, or restricted area 
use) in its annual activity reports submitted to NMFS
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    (b) [Reserved]


Sec.  218.85  Requirements for monitoring and reporting.

    The Action Proponents must implement the following monitoring and 
reporting requirements when conducting the specified activities:
    (a) Notification of take. Action proponent personnel must notify 
NMFS immediately (or as soon as operational security considerations 
allow) if the specified activity identified in Sec.  218.80 is thought 
to have resulted in the mortality or serious injury of any marine 
mammals, or in any Level A harassment or Level B harassment of marine 
mammals not identified in this subpart.
    (b) Monitoring and reporting under the LOAs. The Action Proponents 
must conduct all monitoring and reporting required under the LOAs.
    (c) Notification of injured, live stranded, or dead marine mammals. 
Action Proponent personnel must abide by the Notification and Reporting 
Plan, which sets out notification, reporting, and other requirements 
when dead, injured, or live stranded marine mammals are detected. The 
Notification and Reporting Plan is available at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-military-readiness-activities.
    (d) Annual AFTT Study Area marine species monitoring report. The 
Action Proponents must submit an annual AFTT Study Area marine species 
monitoring report describing the implementation and results from the 
previous calendar year. Data collection methods will be standardized 
across range complexes and the AFTT Study Area to allow for comparison 
in different geographic locations. The draft report must be submitted 
to the Director, Office of Protected Resources, NMFS, annually. NMFS 
will submit comments or questions on the report, if any, within 3 
months of receipt. The report will be considered final after the Action 
Proponents have addressed NMFS' comments, or 3 months after submittal 
of the draft if NMFS does not provide comments on the draft report. The 
report must describe progress of knowledge made with respect to 
intermediate scientific objectives within the AFTT Study Area 
associated with the Integrated Comprehensive Monitoring Program (ICMP). 
Similar study questions must be treated together so that progress on 
each topic can be summarized across all Navy ranges. The report need 
not include analyses and content that do not provide direct assessment 
of cumulative progress on the monitoring plan study questions.
    (e) Quick look reports. In the event that the sound levels analyzed 
in promulgation of these regulations were exceeded within a given 
reporting year, the Action Proponents must submit a preliminary 
report(s) detailing the exceedance within 21 days after the anniversary 
date of issuance of the LOAs.
    (f) Annual AFTT Training and Testing Reports. Regardless of whether 
analyzed sound levels were exceeded, the Navy must submit a detailed 
report (AFTT Annual Training Exercise Report and Testing Activity 
Report) and the Coast Guard must submit a detailed report (AFTT Annual 
Training Exercise Report) to the Director, Office of Protected 
Resources, NMFS annually. NMFS will submit comments or questions on the 
reports, if any, within 1 month of receipt. The reports will be 
considered final after the Action Proponents have addressed NMFS' 
comments, or 1 month after submittal of the drafts if NMFS does not 
provide comments on the draft reports. The annual reports must contain 
a summary of all sound sources used (total hours or quantity (per the 
LOAs) of each bin of sonar or other non-impulsive source; total annual 
number of each type of explosive exercises; and total annual expended/
detonated rounds (missiles, bombs, sonobuoys, etc.) for each explosive 
bin). The annual reports must also contain cumulative sonar and 
explosive use quantity from previous years' reports through the current 
year. Additionally, if there were any changes to the sound source 
allowance in the reporting year, or cumulatively, the reports would 
include a discussion of why the change was made and include analysis to 
support how the change did or did not affect the analysis in the 2024 
AFTT Draft Supplemental EIS/OEIS and MMPA final rule. The annual 
reports must also include the details regarding specific requirements 
associated with the mitigation areas listed in paragraph (f)(4) of this 
section. The analysis in the detailed report must be based on the 
accumulation of data from the current year's report and data collected 
from previous annual reports. The final annual/close-out report at the 
conclusion of the authorization period (year 7) will also serve as the 
comprehensive close-out report and include both the final year annual 
incidental take compared to annual authorized incidental take as well 
as a cumulative 7-year incidental take compared to 7-year authorized 
incidental take. The AFTT Annual Training and Testing Reports must 
include the specific information described in the LOAs.
    (1) MTEs. This section of the report must contain the following 
information for MTEs conducted in the AFTT Study Area.
    (i) Exercise information (for each MTE). For exercise information 
(for each MTE):
    (A) Exercise designator.
    (B) Date that exercise began and ended.
    (C) Location.
    (D) Number and types of active sonar sources used in the exercise.
    (E) Number and types of passive acoustic sources used in exercise.
    (F) Number and types of vessels, aircraft, and other platforms 
participating in each exercise.
    (G) Total hours of all active sonar source operation.
    (H) Total hours of each active sonar source bin.
    (I) Wave height (high, low, and average) during exercise.
    (ii) Individual marine mammal sighting information for each 
sighting in each exercise where mitigation was implemented. For 
individual marine mammal sighting information for each sighting in each 
exercise where mitigation was implemented:
    (A) Date, time, and location of sighting.
    (B) Species (if not possible, indication of whale/dolphin/
pinniped).
    (C) Number of individuals.
    (D) Initial Detection Sensor (e.g., passive sonar, Lookout).
    (E) Indication of specific type of platform observation was made 
from (including, for example, what type of surface vessel or testing 
platform).
    (F) Length of time observers maintained visual contact with marine 
mammal.
    (G) Sea state.
    (H) Visibility.
    (I) Sound source in use at the time of sighting.
    (J) Indication of whether animal was less than 200 yd (182.9 m), 
200 to 500 yd (182.9 to 457.2 m), 500 to 1,000 yd (457.2 m to 914.4 m), 
1,000 to 2,000 yd (914.4 m to 1,828.8 m), or greater than 2,000 yd 
(1,828.8 m) from sonar source.
    (K) Whether operation of sonar sensor was delayed, or sonar was 
powered or shut down, and the length of the delay.
    (L) If source in use was hull-mounted, true bearing of animal from 
the vessel, true direction of vessel's travel, and estimation of 
animal's motion relative to vessel (opening, closing, parallel).
    (M) Lookouts must report, in plain language and without trying to 
categorize in any way, the observed behavior of the animal(s) (such as

[[Page 20076]]

animal closing to bow ride, paralleling course/speed, floating on 
surface and not swimming, etc.) and if any calves were present.
    (iii) An evaluation (based on data gathered during all of the MTEs) 
of the effectiveness of mitigation measures designed to minimize the 
received level to which marine mammals may be exposed. For an 
evaluation (based on data gathered during all of the MTEs) of the 
effectiveness of mitigation measures designed to minimize the received 
level to which marine mammals may be exposed:
    (A) This evaluation must identify the specific observations that 
support any conclusions the Navy reaches about the effectiveness of the 
mitigation.
    (B) [Reserved]
    (2) Sinking Exercises. This section of the report must include the 
following information for each SINKEX completed that year in the AFTT 
Study Area:
    (i) Exercise information. For exercise information:
    (A) Location.
    (B) Date and time exercise began and ended.
    (C) Total hours of observation by Lookouts before, during, and 
after exercise.
    (D) Total number and types of explosive source bins detonated.
    (E) Number and types of passive acoustic sources used in exercise.
    (F) Total hours of passive acoustic search time.
    (G) Number and types of vessels, aircraft, and other platforms 
participating in exercise.
    (H) Wave height in feet (high, low, and average) during exercise.
    (I) Narrative description of sensors and platforms utilized for 
marine mammal detection and timeline illustrating how marine mammal 
detection was conducted.
    (ii) Individual marine mammal observation (by Action Proponent 
Lookouts) information for each sighting where mitigation was 
implemented. For individual marine mammal observation (by Action 
Proponent Lookouts) information for each sighting where mitigation was 
implemented:
    (A) Date/Time/Location of sighting.
    (B) Species (if not possible, indicate whale, dolphin, or 
pinniped).
    (C) Number of individuals.
    (D) Initial detection sensor (e.g., sonar or Lookout).
    (E) Length of time observers maintained visual contact with marine 
mammal.
    (F) Sea state.
    (G) Visibility.
    (H) Whether sighting was before, during, or after detonations/
exercise, and how many minutes before or after.
    (I) Distance of marine mammal from actual detonations (or target 
spot if not yet detonated): Less than 200 yd (182.9 m), 200 to 500 yd 
(182.9 to 457.2 m), 500 to 1,000 yd (457.2 m to 914.4 m), 1,000 to 
2,000 yd (914.4 m to 1,828.8 m), or greater than 2,000 yd (1,828.8 m).
    (J) Lookouts must report, in plain language and without trying to 
categorize in any way, the observed behavior of the animal(s) (such as 
animal closing to bow ride, paralleling course/speed, floating on 
surface and not swimming etc.), including speed and direction and if 
any calves were present.
    (K) The report must indicate whether explosive detonations were 
delayed, ceased, modified, or not modified due to marine mammal 
presence and for how long.
    (L) If observation occurred while explosives were detonating in the 
water, indicate munition type in use at time of marine mammal 
detection.
    (3) Summary of sources used. This section of the report must 
include the following information summarized from the authorized sound 
sources used in all training and testing events:
    (i) Totals for sonar or other acoustic source bins. Total annual 
hours or quantity (per the LOA) of each bin of sonar or other acoustic 
sources (e.g., pile driving and air gun activities); and
    (ii) Total for explosive bins. Total annual expended/detonated 
ordnance (missiles, bombs, sonobuoys, etc.) for each explosive bin.
    (4) Special reporting for geographic mitigation areas. This section 
of the report must contain the following information for activities 
conducted in geographic mitigation areas in the AFTT Study Area:
    (i) Northeast North Atlantic Right Whale Mitigation Area. The 
Action Proponents must report the total annual hours and counts of 
active sonar and in-water explosives (including underwater explosives 
and explosives deployed against surface targets) used in the mitigation 
area.
    (ii) Gulf of Maine Marine Mammal Mitigation Area. The Action 
Proponents must report the total annual hours and counts of active 
sonar and in-water explosives (including underwater explosives and 
explosives deployed against surface targets) used in the mitigation 
area.
    (iii) Southeast North Atlantic Right Whale Mitigation Area. The 
Action Proponents must report the total annual hours and counts of 
active sonar and in-water explosives (including underwater explosives 
and explosives deployed against surface targets) used in the mitigation 
area from November 15 to April 15.
    (iv) Southeast North Atlantic Right Whale Special Reporting 
Mitigation Area. The Action Proponents must report the total annual 
hours and counts of active sonar and in-water explosives (including 
underwater explosives and explosives deployed against surface targets) 
used within the mitigation area from November 15 to April 15.
    (v) Rice's Whale Mitigation Area. The Action Proponents must report 
the total annual hours and counts of active sonar and in-water 
explosives (including underwater explosives and explosives deployed 
against surface targets) used in the mitigation area.
    (vi) National security requirement. If an Action Proponent(s) 
evokes the national security requirement described in Sec.  
218.84(a)(2)(ix), the Action Proponent personnel must include 
information about the event in its Annual AFTT Training and Testing 
Report.
    (g) MTE sonar exercise notification. The Action Proponents must 
submit to NMFS (contact as specified in the LOAs) an electronic report 
within 15 calendar days after the completion of any MTE indicating:
    (1) Location. Location of the exercise;
    (2) Dates. Beginning and end dates of the exercise; and
    (3) Type. Type of exercise.


Sec.  218.86  Letters of Authorization.

    (a) To incidentally take marine mammals pursuant to this subpart, 
the Action Proponents must apply for and obtain LOAs.
    (b) An LOA, unless suspended or revoked, may be effective for a 
period of time not to exceed the expiration date of this subpart.
    (c) In the event of projected changes to the activity or to 
mitigation, monitoring, or reporting measures (excluding changes made 
pursuant to the adaptive management provision of Sec.  218.87(c)(1)) 
required by an LOA, the Action Proponent must apply for and obtain a 
modification of the LOA as described in Sec.  218.87.
    (d) Each LOA will set forth:
    (1) Permissible methods of incidental taking;
    (2) Geographic areas for incidental taking;
    (3) Means of effecting the least practicable adverse impact (i.e., 
mitigation) on the species and stocks of marine mammals and their 
habitat; and
    (4) Requirements for monitoring and reporting.
    (e) Issuance of the LOA(s) must be based on a determination that 
the level of taking is consistent with the findings

[[Page 20077]]

made for the total taking allowable under the regulations of this 
subpart.
    (f) Notice of issuance or denial of the LOA(s) will be published in 
the Federal Register within 30 days of a determination.


Sec.  218.87  Modifications of Letters of Authorization.

    (a) An LOA issued under Sec. Sec.  216.106 of this chapter and 
218.86 for the activity identified in Sec.  218.80(c) shall be 
modified, upon request by the LOA Holder, provided that:
    (1) The specified activity and mitigation, monitoring, and 
reporting measures, as well as the anticipated impacts, are the same as 
those described and analyzed for the regulations in this subpart 
(excluding changes made pursuant to the adaptive management provision 
in paragraph (c)(1) of this section); and
    (2) NMFS determines that the mitigation, monitoring, and reporting 
measures required by the previous LOAs under this subpart were 
implemented.
    (b) For LOA modification requests by the applicants that include 
changes to the activity or to the mitigation, monitoring, or reporting 
measures (excluding changes made pursuant to the adaptive management 
provision in paragraph (c)(1) of this section), the LOA should be 
modified provided that:
    (1) NMFS determines that the change(s) to the activity or the 
mitigation, monitoring or reporting do not change the findings made for 
the regulations and do not result in more than a minor change in the 
total estimated number of takes (or distribution by species or stock or 
years), and
    (2) NMFS may publish a notice of proposed modified LOA in the 
Federal Register, including the associated analysis of the change, and 
solicit public comment before issuing the LOA.
    (c) An LOA issued under Sec. Sec.  216.106 and 218.86 of this 
chapter for the activities identified in Sec.  218.80(c) may be 
modified by NMFS Office of Protected Resources under the following 
circumstances:
    (1) After consulting with the Action Proponents regarding the 
practicability of the modifications, through adaptive management, NMFS 
may modify (including remove, revise or add to) the existing 
mitigation, monitoring, or reporting measures if doing so creates a 
reasonable likelihood of more effectively accomplishing the goals of 
the mitigation and monitoring measures set forth in this subpart.
    (i) Possible sources of data that could contribute to the decision 
to modify the mitigation, monitoring, or reporting measures in an LOA 
include, but are not limited to:
    (A) Results from the Action Proponents' monitoring report and 
annual exercise reports from the previous year(s);
    (B) Results from other marine mammal and/or sound research or 
studies; or
    (C) Any information that reveals marine mammals may have been taken 
in a manner, extent, or number not authorized by this subpart or 
subsequent LOAs.
    (ii) If, through adaptive management, the modifications to the 
mitigation, monitoring, or reporting measures are substantial, NMFS 
shall publish a notice of proposed LOA(s) in the Federal Register and 
solicit public comment.
    (2) If the NMFS Office of Protected Resources determines that an 
emergency exists that poses a significant risk to the well-being of the 
species or stocks of marine mammals specified in LOAs issued pursuant 
to Sec. Sec.  216.106 of this chapter and 218.86, a LOA may be modified 
without prior notice or opportunity for public comment. Notice would be 
published in the Federal Register within 30 days of the action.


Sec. Sec.  218.88-218.89  [Reserved]

[FR Doc. 2025-07780 Filed 5-8-25; 8:45 am]
BILLING CODE 3510-22-P