30006 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

permit (71 FR 58057; October 2, 2006). 

These certificate(s) are valid for 3 years. 

Certificates issued in 2018 will be 

expiring in 2021. As such, vessel 

owners who have not already attended 

a workshop and received a NMFS 

certificate, or vessel owners whose 

certificate(s) will expire prior to the next 

permit renewal, must attend a workshop 

to fish with, or renew, their swordfish 

and shark limited-access permits. 

Additionally, new shark and swordfish 

limited-access permit applicants who 

intend to fish with longline or gillnet 

gear must attend a Safe Handling, 

Release, and Identification Workshop 

and submit a copy of their workshop 

certificate before either of the permits 

will be issued. Approximately 376 free 

Safe Handling, Release, and 

Identification Workshops have been 

conducted since 2006. 

In addition to vessel owners, at least 

one operator on board vessels issued a 

limited-access swordfish or shark 

permit that uses longline or gillnet gear 

is required to attend a Safe Handling, 

Release, and Identification Workshop 

and receive a certificate. Vessels that 

have been issued a limited-access 

swordfish or shark permit and that use 

longline or gillnet gear may not fish 

unless both the vessel owner and 

operator have valid workshop 

certificates onboard at all times. Vessel 

operators who have not already 

attended a workshop and received a 

NMFS certificate, or vessel operators 

whose certificate(s) will expire prior to 

their next fishing trip, must attend a 

workshop to operate a vessel with 

swordfish and shark limited-access 

permits on which longline or gillnet 

gear is used. 

Workshop Dates, Times, and Locations 

1. July 20, 2021, 9 a.m.–5 p.m., Hilton 

Hotel, 5400 Seawall Boulevard, 

Galveston, TX 77551. 

2. July 28, 2021, 9 a.m.–5 p.m., 

Holiday Inn, 151 Route 72, 

Manahawkin, NJ 08050. 

3. August 3, 2021, 9 a.m.–5 p.m., 

Holiday Inn, 3384 Ocean Drive, Vero 

Beach, FL 32963. 

4. August 31, 2021, 9 a.m.–5 p.m., 

Hampton Inn, 678 Citadel Haven Drive, 

Charleston, SC 29414. 

5. September 3, 2021, 9 a.m.–5 p.m., 

Marriott Courtyard, 5000 Express Drive 

South, Ronkonkoma, NY 11779. 

6. September 10, 2021, 9 a.m.–5 p.m., 

Holiday Inn, 9515 US 49, Gulfport, MS 

39503. 

Registration 

To register for a scheduled Safe 

Handling, Release, and Identification 

Workshop, please contact Angler 

Conservation Education at (386) 682– 

0158. Pre-registration is highly 

recommended, but not required. 

Registration Materials 

To ensure that workshop certificates 

are linked to the correct permits, 

participants will need to bring the 

following specific items with them to 

the workshop: 

• Individual vessel owners must 

bring a copy of the appropriate 

swordfish and/or shark permit(s), a copy 

of the vessel registration or 

documentation, and proof of 

identification; 

• Representatives of a businessowned or co-owned vessel must bring 

proof that the individual is an agent of 

the business (such as articles of 

incorporation), a copy of the applicable 

swordfish and/or shark permit(s), and 

proof of identification; and 

• Vessel operators must bring proof of 

identification. 

Workshop Objectives 

The Safe Handling, Release, and 

Identification Workshops are designed 

to teach longline and gillnet fishermen 

the required techniques for the safe 

handling and release of entangled and/ 

or hooked protected species, such as sea 

turtles, marine mammals, smalltooth 

sawfish, Atlantic sturgeon, and 

prohibited sharks. In an effort to 

improve reporting, the proper 

identification of protected species and 

prohibited sharks will also be taught at 

these workshops. Additionally, 

individuals attending these workshops 

will gain a better understanding of the 

requirements for participating in these 

fisheries. The overall goal of these 

workshops is to provide participants 

with the skills needed to reduce the 

mortality of protected species and 

prohibited sharks, which may prevent 

additional regulations on these fisheries 

in the future. 

Authority: 16 U.S.C. 1801 et seq. 

Dated: May 28, 2021. 

Jennifer M. Wallace, 

Acting Director, Office of Sustainable 

Fisheries, National Marine Fisheries Service. 

[FR Doc. 2021–11712 Filed 6–3–21; 8:45 am] 

BILLING CODE 3510–22–P 

DEPARTMENT OF COMMERCE 

National Oceanic and Atmospheric 

Administration 

[RTID 0648–XB083] 

Takes of Marine Mammals Incidental to 

Specified Activities; Taking Marine 

Mammals Incidental to a Geophysical 

Survey of the Queen Charlotte Fault 

AGENCY: National Marine Fisheries 

Service (NMFS), National Oceanic and 

Atmospheric Administration (NOAA), 

Commerce. 

ACTION: Notice; proposed incidental 

harassment authorization; request for 

comments on proposed authorization 

and possible renewal. 

SUMMARY: NMFS has received a request 

from the Lamont-Doherty Earth 

Observatory of Columbia University (L– 

DEO) for authorization to take marine 

mammals incidental to a marine 

geophysical survey of the Queen 

Charlotte Fault in the Northeast Pacific 

Ocean. The proposed survey would be 

funded by the National Science 

Foundation (NSF). Pursuant to the 

Marine Mammal Protection Act 

(MMPA), NMFS is requesting comments 

on its proposal to issue an incidental 

harassment authorization (IHA) to 

incidentally take marine mammals 

during the specified activities. NMFS is 

also requesting comments on a possible 

one-time, one-year renewal that could 

be issued under certain circumstances 

and if all requirements are met, as 

described in Request for Public 

Comments at the end of this notice. 

NMFS will consider public comments 

prior to making any final decision on 

the issuance of the requested MMPA 

authorizations and agency responses 

will be summarized in the final notice 

of our decision. 

DATES: Comments and information must 

be received no later than July 6, 2021. 

ADDRESSES: Comments should be 

addressed to Jolie Harrison, Chief, 

Permits and Conservation Division, 

Office of Protected Resources, National 

Marine Fisheries Service. Physical 

comments should be sent to 1315 EastWest Highway, Silver Spring, MD 20910 

and electronic comments should be sent 

to ITP.Laws@noaa.gov. 

Instructions: NMFS is not responsible 

for comments sent by any other method, 

to any other address or individual, or 

received after the end of the comment 

period. Comments received 

electronically, including all 

attachments, must not exceed a 25- 

megabyte file size. All comments 

received are a part of the public record 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30007 

and will generally be posted online at 

www.fisheries.noaa.gov/permit/ 

incidental-take-authorizations-undermarine-mammal-protection-act without 

change. All personal identifying 

information (e.g., name, address) 

voluntarily submitted by the commenter 

may be publicly accessible. Do not 

submit confidential business 

information or otherwise sensitive or 

protected information. 

FOR FURTHER INFORMATION CONTACT: Ben 

Laws, Office of Protected Resources, 

NMFS, (301) 427–8401. Electronic 

copies of the application and supporting 

documents, as well as a list of the 

references cited in this document, may 

be obtained online at: 

www.fisheries.noaa.gov/permit/ 

incidental-take-authorizations-undermarine-mammal-protection-act. In case 

of problems accessing these documents, 

please call the contact listed above. 

SUPPLEMENTARY INFORMATION: 

Background 

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 

issued or, if the taking is limited to 

harassment, a notice of a proposed 

incidental take authorization may be 

provided to the public for review. 

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 and 

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 mitigation, monitoring 

and reporting of the takings are set forth. 

The definitions of all applicable MMPA 

statutory terms cited above are included 

in the relevant sections below. 

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 action (i.e., the issuance of an 

IHA) with respect to potential impacts 

on the human environment. 

Accordingly, NMFS plans to adopt 

NSF’s Environmental Assessment (EA), 

as we have preliminarily determined 

that it includes adequate information 

analyzing the effects on the human 

environment of issuing the IHA. NSF’s 

EA is available at www.nsf.gov/geo/oce/ 

envcomp/. 

We will review all comments 

submitted in response to this notice 

prior to concluding our NEPA process 

or making a final decision on the IHA 

request. 

Summary of Request 

On December 3, 2019, NMFS received 

a request from L–DEO for an IHA to take 

marine mammals incidental to a 

geophysical survey of the Queen 

Charlotte Fault (QCF) off of Alaska and 

British Columbia, Canada. L–DEO 

submitted a revised version of the 

application on April 2, 2020. On April 

10, 2020, L–DEO informed NMFS that 

the planned survey would be deferred to 

2021 as a result of issues related to the 

COVID–19 pandemic. L–DEO 

subsequently submitted revised versions 

of the application on October 22 and 

December 16, 2020, the latter of which 

was deemed adequate and complete. A 

final, revised version was submitted on 

January 11, 2021. L–DEO’s request is for 

take of 21 species of marine mammals 

by Level B harassment. In addition, 

NMFS proposes to authorize take by 

Level A harassment for seven of these 

species. 

Description of Proposed Activity 

Overview 

Researchers from L–DEO, the 

University of New Mexico, and Western 

Washington University, with funding 

from NSF, propose to conduct a highenergy seismic survey from the Research 

Vessel (R/V) Marcus G. Langseth 

(Langseth) at the QCF in the northeast 

Pacific Ocean during late summer 2021. 

Other research collaborators include 

Dalhousie University, the Geological 

Survey of Canada, and the U.S. 

Geological Survey. The proposed twodimensional (2–D) seismic survey 

would occur within the Exclusive 

Economic Zones (EEZ) of the United 

States and Canada, including in 

Canadian territorial waters. The survey 

would use a 36-airgun towed array with 

a total discharge volume of ∼6,600 cubic 

inches (in3) as an acoustic source, 

acquiring return signals using both a 

towed streamer as well as ocean bottom 

seismometers (OBSs). 

The proposed study would use 2–D 

seismic surveying to characterize crustal 

and uppermost mantle velocity 

structure, fault zone architecture and 

rheology, and seismicity of the QCF. 

The QCF system is an approximately 

1,200 kilometer (km)-long onshoreoffshore transform system connecting 

the Cascadia and Alaska-Aleutian 

subduction zones; the QCF is the 

approximately 900 km-long offshore 

component of the transform system. The 

purpose of the proposed study is to 

characterize an approximately 450-km 

segment of the fault that encompasses 

systematic variations in key parameters 

in space and time: (1) Changes in fault 

obliquity relative to Pacific-North 

American plate motion leading to 

increased convergence from north to 

south; (2) Pacific plate age and 

theoretical mechanical thickness 

decrease from north to south; and (3) a 

shift in Pacific plate motion at 

approximately 12–6 million years ago 

that may have increased convergence 

along the entire length of the fault, 

possibly initiating underthrusting in the 

southern portion of the study area. 

Current understanding of how these 

variations are expressed through 

seismicity, crustal-scale deformation, 

and lithospheric structure and dynamics 

is limited due to lack of instrumentation 

and modern seismic imaging. 

Dates and Duration 

The proposed survey is expected to 

last for approximately 36 days, 

including approximately 27 days of 

seismic operations, 3 days of equipment 

deployment/retrieval, 2 days of transits, 

and 4 contingency days (accounting for 

potential delays due to, e.g., weather). 

R/V Langseth would likely leave out of 

and return to port in Ketchikan, Alaska, 

during July–August 2021. 

Specific Geographic Region 

The proposed survey would occur 

within the area of approximately 52–57° 

N and approximately 131–137° W. 

Representative survey tracklines are 

shown in Figure 1. Some deviation in 

actual track lines, including the order of 

survey operations, could be necessary 

for reasons such as science drivers, poor 

data quality, inclement weather, or 

mechanical issues with the research 

vessel and/or equipment. The survey is 

proposed to occur within the EEZs of 

the United States and Canada, including 

Alaskan state waters and Canadian 

territorial waters, ranging in depth from 

30008 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

50–2,800 meters (m). Approximately 

4,250 km of transect lines would be 

surveyed, with 13 percent of the 

transect lines in Canadian territorial 

waters. Most of the survey (69 percent) 

would occur in deep water (>1,000 m), 

30 percent would occur in intermediate 

water (100–1,000 m deep), and 

approximately 1 percent would take 

place in shallow water <100 m deep. 

Note that the MMPA does not apply 

in Canadian territorial waters. L–DEO is 

subject only to Canadian law in 

conducting that portion of the survey. 

However, NMFS has calculated the 

expected level of incidental take in the 

entire activity area (including Canadian 

territorial waters) as part of the analysis 

supporting our determination under the 

MMPA that the activity will have a 

negligible impact on the affected species 

(see Estimated Take and Negligible 

Impact Analysis and Determination). 

BILLING CODE 3510–22–P 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30009 

BILLING CODE 3510–22–C 


EN04JN21.003</GPH>

z 

i8 

z 

i8 

z 

ia 

z 

13 "W 

Q 

Pacific o 

Ocean 

Legend 

Ocean Bottom Seismometer Type: 

• Short-period 

+ Broadband 

• Both (Short-period & Broadband) 

- Survey Transects 

- - 200 Nautical Miles 

- - - 12 Nautical Miles 

- 3 Nautical Miles 

- lsobath (m) 

- Critical Habitat - Steller Sea Lion 

1 ·w 13 ·w 

0 

.., 

,f'°<>oolf. '\~ .( 

50 75 1~l/' ,{\. ~ / 

:::::::::::::;;;;;::::::::E--3;::::;:::::::::::..'1° C. n ~ Kilometres 

13 "W 

Figure 1. Location of the Proposed Seismic Survey in the Northeast Pacific 

Ocean 
30010 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

Detailed Description of Specific Activity 

The procedures to be used for the 

proposed survey would be similar to 

those used during previous seismic 

surveys by L–DEO and would use 

conventional seismic methodology. The 

surveys would involve one source 

vessel, the R/V Langseth. R/V Langseth 

would deploy an array of 36 airguns as 

an energy source with a total volume of 

6,600 in3. The array consists of 36 

elements, including 20 Bolt 1500LL 

airguns with volumes of 180 to 360 in3

and 16 Bolt 1900LLX airguns with 

volumes of 40 to 120 in3. The airgun 

array configuration is illustrated in 

Figure 2–11 of NSF and USGS’s 

Programmatic Environmental Impact 

Statement (PEIS; NSF–USGS, 2011). 

(The PEIS is available online at: 

www.nsf.gov/geo/oce/envcomp/usgsnsf-marine-seismic-research/nsf-usgsfinal-eis-oeis-with-appendices.pdf). The 

vessel speed during seismic operations 

would be approximately 4.2 knots (kn) 

(∼7.8 km/hour) during the survey and 

the airgun array would be towed at a 

depth of 12 m. The receiving system 

would consist of OBSs and a towed 

hydrophone streamer with a nominal 

length of 15 km (OBS and multi-channel 

seismic (MCS) shooting). As the airguns 

are towed along the survey lines, the 

hydrophone streamer would transfer the 

data to the on-board processing system, 

and the OBSs would receive and store 

the returning acoustic signals internally 

for later analysis. 

Approximately 60 short-period OBSs 

would be deployed and subsequently 

retrieved at a total of 123 sites in 

multiple phases from a second vessel, 

the Canadian Coast Guard ship John P. 

Tully (CCGS Tully). Along OBS 

refraction lines, OBSs would be 

deployed by CCGS Tully at 10 km 

intervals, with a spacing of 5 km over 

the central 40 km of the fault zone for 

fault-normal crossings. Twenty-eight 

broadband OBS instruments would also 

collect data during the survey and 

would be deployed prior to the activesource seismic survey, depending on 

logistical constraints. When an OBS is 

ready to be retrieved, an acoustic release 

transponder (pinger) interrogates the 

instrument at a frequency of 8–11 kHz; 

a response is received at 11.5–13 kHz. 

The burn-wire release assembly is then 

activated, and the instrument is released 

from its 80-kg anchor to float to the 

surface. Take of marine mammals is not 

expected to occur incidental to L–DEO’s 

use of OBSs. 

The airguns would fire at a shot 

interval of 50 m (approximately 23 s) 

during MCS shooting with the 

hydrophone streamer (approximately 42 

percent of survey effort), at a 150-m 

interval (approximately 69 s) during 

refraction surveying to OBSs 

(approximately 29 percent of survey 

effort), and at a shot interval of every 

minute (approximately 130 m) during 

turns (approximately 29 percent of 

survey effort). 

Short-period OBSs would be 

deployed first along five OBS refraction 

lines by CCGS Tully. Two OBS lines run 

parallel to the coast, and three are 

perpendicular to the coast; one 

perpendicular line is located off 

Southeast Alaska, one is off Haida 

Gwaii, British Columbia, and another is 

located in Dixon Entrance. Please see 

Figure 1 for all location references. 

Following refraction shooting of a single 

line, short-period instruments on that 

line would be recovered, serviced, and 

redeployed on a subsequent refraction 

line while MCS data would be acquired 

by the Langseth. MCS lines would be 

acquired off Southeast Alaska, Haida 

Gwaii, and Dixon Entrance. The coastparallel OBS refraction transect nearest 

to shore would only be surveyed once 

at OBS shot spacing. The other coastparallel OBS refraction transect (on the 

ocean side) would be acquired twice, 

once during refraction and once during 

reflection surveys. In addition, portions 

of the three coast-perpendicular OBS 

refraction lines would also be surveyed 

twice, once for OBS shot spacing and 

once for MCS shot spacing. The 

coincident reflection/refraction profiles 

that run parallel to the coast would be 

acquired in multiple segments to ensure 

straight-line geometry. Sawtooth transits 

during which seismic data would be 

acquired would take place between 

transect lines when possible; otherwise, 

boxcar turns would be performed to 

save time. Both reflection and refraction 

surveys would use the same airgun 

array with the same discharge volume. 

There could be additional seismic 

operations associated with turns, airgun 

testing, and repeat coverage of any areas 

where initial data quality is substandard, and 25 percent has been 

added to the assumed survey line-kms 

to account for this potential. 

Note that the location of some 

tracklines has been modified from the 

original proposal as represented in 

Figure 1 and reflected in the take 

estimation analysis (see Estimated 

Take). However, these minor 

modifications do not substantively 

impact the location of survey effort or 

the proportion of survey effort in 

different depth bins and, therefore, the 

original take estimates remain accurate. 

In addition to the operations of the 

airgun array, a multibeam echosounder 

(MBES), a sub-bottom profiler (SBP), 

and an Acoustic Doppler Current 

Profiler (ADCP) would be operated from 

R/V Langseth continuously during the 

seismic surveys, but not during transit 

to and from the survey area. Take of 

marine mammals is not expected to 

occur incidental to use of the MBES, 

SBP, or ADCP because they will be 

operated only during seismic 

acquisition, and it is assumed that, 

during simultaneous operations of the 

airgun array and the other sources, any 

marine mammals close enough to be 

affected by the MBES, SBP, and ADCP 

would already be affected by the 

airguns. However, whether or not the 

airguns are operating simultaneously 

with the other sources, given the other 

sources’ characteristics (e.g., narrow 

downward-directed beam), marine 

mammals would experience no more 

than one or two brief ping exposures 

from them, if any exposure were to 

occur. Proposed mitigation, monitoring, 

and reporting measures are described in 

detail later in this document (please see 

Proposed Mitigation and Proposed 

Monitoring and Reporting). 

Description of Marine Mammals in the 

Area of Specified Activities 

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. Additional information 

regarding population trends and threats 

may be found in NMFS’ Stock 

Assessment Reports (SARs; 

www.fisheries.noaa.gov/national/ 

marine-mammal-protection/marinemammal-stock-assessments) and more 

general information about these species 

(e.g., physical and behavioral 

descriptions) may be found on NMFS’ 

website (www.fisheries.noaa.gov/findspecies). 

Table 1 lists all species with expected 

potential for occurrence in the survey 

area and summarizes information 

related to the population or stock, 

including regulatory status under the 

MMPA and Endangered Species Act 

(ESA) and potential biological removal 

(PBR), where known. For taxonomy, we 

follow Committee on Taxonomy (2020). 

PBR is defined by the MMPA as the 

maximum number of animals, not 

including natural mortalities, that may 

be removed from a marine mammal 

stock while allowing that stock to reach 

or maintain its optimum sustainable 

population (as described in NMFS’s 

SARs). While no mortality is anticipated 

or authorized here, PBR and annual 

serious injury and mortality from 

anthropogenic sources are included here 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30011 

as gross indicators of the status of the 

species and other threats. 

Marine mammal abundance estimates 

presented in this document represent 

the total number of individuals that 

make up a given stock or the total 

number estimated within a particular 

study or survey area. NMFS’ stock 

abundance estimates for most species 

represent the total estimate of 

individuals within the geographic area, 

if known, that comprises that stock. For 

some species, this geographic area may 

extend beyond U.S. waters. All managed 

stocks in this region are assessed in 

NMFS’ U.S. Pacific and Alaska SARs. 

All MMPA stock information presented 

in Table 1 is the most recent available 

at the time of publication and is 

available in the 2019 SARs (Caretta et 

al., 2020; Muto et al., 2020) and draft 

2020 SARs (available online at: 

www.fisheries.noaa.gov/national/ 

marine-mammal-protection/draftmarine-mammal-stock-assessmentreports). Where available, abundance 

and status information is also presented 

for marine mammals in British 

Columbia waters. 

Twenty-one species (with 28 managed 

stocks) are considered to have the 

potential to occur in the proposed 

survey area. Species that could 

potentially occur in the proposed 

research area but are not likely to be 

harassed due to the rarity of their 

occurrence (i.e., are considered 

extralimital or rare visitors to southeast 

Alaska/northern British Columbia) are 

described briefly but omitted from 

further analysis. These generally 

include species that do not normally 

occur in the area but for which there are 

one or more occurrence records that are 

considered beyond the normal range of 

the species. These species include 

pygmy sperm whale (Kogia breviceps), 

dwarf sperm whale (K. sima), 

Blainville’s beaked whale (Mesoplodon 

densirostris), Hubbs’ beaked whale 

(Mesoplodon carlhubbsi), false killer 

whale (Pseudorca crassidens), shortfinned pilot whale (Globicephala 

macrorhynchus), common bottlenose 

dolphin (Tursiops truncatus), common 

dolphin (Delphius delphis), striped 

dolphin (Stenella coeruleoalba), and 

rough-toothed dolphin (Steno 

bredanensis), which are all typically 

distributed further south in the 

California Current ecosystem, and 

beluga whales (Delphinapterus leucas), 

which are found further north, with a 

population in Yakutat Bay. 

The North Pacific right whale 

(Eubalaena japonica) historically 

occurred across the North Pacific Ocean 

in subpolar to temperate waters, 

including waters off the coast of British 

Columbia (Scarff, 1986; Clapham et al., 

2004). Sightings of this endangered 

species are now extremely rare, 

occurring primarily in the Okhotsk Sea 

and the eastern Bering Sea (Brownell et 

al., 2001; Shelden et al., 2005; Wade et 

al., 2006; Zerbini et al., 2010). In 2013, 

two North Pacific right whale sightings 

were made off the coast of British 

Columbia (U.S. Department of the Navy, 

2015). There have also been four 

sightings, each of a single North Pacific 

right whale, in California waters within 

approximately the last 30 years (most 

recently in 2017) (Carretta et al., 1994; 

Brownell et al., 2001; Price, 2017). 

There is a very low probability of 

encountering this species in the action 

area, and it is not discussed further. 

There are eight killer whale stocks 

recognized in the U.S. Pacific, with 

Southern Resident killer whales being 

the only ESA-listed population. 

Southern Resident killer whales 

primarily occur in the southern Strait of 

Georgia, Strait of Juan de Fuca, Puget 

Sound, and the southern half of the west 

coast of Vancouver Island (Carretta et 

al., 2020). However, they have been 

observed in southeast Alaska. In 2007, 

whales from L-pod were sighted off 

Chatham Strait, Alaska, the farthest 

north they have ever been documented 

(Carretta et al., 2020). During the 

summer, Southern Resident killer 

whales typically spend their time 

within the inland waters of Washington 

and southern British Columbia, south of 

the proposed survey area. There is a 

very low probability of encountering 

this stock in the action area, and it is not 

discussed further. 

In addition, the northern sea otter 

(Enhydra lutris kenyoni) is found in 

coastal waters of Alaska. However, this 

species is managed by the U.S. Fish and 

Wildlife Service and is not considered 

further in this document. 

TABLE 1—MARINE MAMMALS THAT COULD OCCUR IN THE SURVEY AREA

Common name Scientific name Stock 

ESA/ 

MMPA 

status; 

strategic 

(Y/N) 1

Stock abundance 

(CV, Nmin, most recent 

abundance survey) 2

British 

Columbia 

abundance 3

PBR Annual 

M/SI 4

Order Cetartiodactyla—Cetacea—Superfamily Mysticeti (baleen whales) 

Family Eschrichtiidae: Gray 

whale 

Eschrichtius robustus ........ Eastern North Pacific 

(ENP) *.

-; N 26,960 (0.05; 25,849; 

2016).

........................ 801 131 

Western North Pacific 

(WNP) *.

E/D; Y 290 (n/a; 271; 2016) ........................ 0.12 Unk 

Family Balaenopteridae 

(rorquals): 

Humpback whale ........ Megaptera novaeangliae 

kuzira.

Central North Pacific 

(CNP) *.

E/D; Y 10,103 (0.3; 7,891; 

2006).

1,029 83 26 

Minke whale ................ Balaenoptera acutorostrata 

scammoni.

Alaska * .............................. -; N Unknown ................... 522 Undet. 0 

Sei whale .................... B. borealis borealis ............ ENP ................................... E/D; Y 519 (0.4; 374; 2014) ........................ 0.75 ≥0.2 

Fin whale .................... B. physalus physalus ......... Northeast Pacific * ............. E/D; Y Unknown ................... 329 Undet. 0.6 

Blue whale .................. B. musculus musculus ....... ENP ................................... E/D; Y 1,496 (0.44; 1,050; 

2014).

........................ 71.2 ≥19.4 

Superfamily Odontoceti (toothed whales, dolphins, and porpoises) 

Family Physeteridae: 

Sperm whale 

Physeter macrocephalus ... North Pacific * .................... E/D; Y Unknown ................... ........................ Undet. 3.5 

Family Ziphiidae (beaked 

whales): 

Cuvier’s beaked whale Ziphius cavirostris .............. Alaska * .............................. -; N Unknown ................... ........................ Undet. 0 

Baird’s beaked whale Berardius bairdii ................. Alaska * .............................. -; N Unknown ................... ........................ Undet. 0 

Stejneger’s beaked 

whale.

Mesoplodon stejnegeri ...... Alaska * .............................. -; N Unknown ................... ........................ Undet. 0 

Family Delphinidae: 


I I I I 
30012 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

TABLE 1—MARINE MAMMALS THAT COULD OCCUR IN THE SURVEY AREA—Continued 

Common name Scientific name Stock 

ESA/ 

MMPA 

status; 

strategic 

(Y/N) 1

Stock abundance 

(CV, Nmin, most recent 

abundance survey) 2

British 

Columbia 

abundance 3

PBR Annual 

M/SI 4

Pacific white-sided dolphin.Lagenorhynchus 

obliquidens.

North Pacific 6 .................... -; N 26,880 (n/a; 26,880; 

1990).

22,160 Undet. 0 

Northern right whale 

dolphin.

Lissodelphis borealis ......... CA/OR/WA ......................... -; N 26,556 (0.44; 18,608; 

2014).

........................ 179 3.8 

Risso’s dolphin ............ Grampus griseus ............... CA/OR/WA ......................... -; N 6,336 (0.32; 4,817; 

2014).

........................ 46 ≥3.7 

Killer whale ................. Orcinus orca 5 .................... ENP Offshore .................... -; N 300 (0.1; 276; 2012) 371 2.8 0 

ENP Gulf of Alaska, Aleutian Islands, and Bering 

Sea Transient.

-; N 587 (n/a; 2012) ......... 5.9 0.8 

ENP West Coast Transient -; N 349 (n/a; 2018) ......... 3.5 0.4 

ENP Alaska Resident ........ -; N 2,347 (n/a; 2012) ...... 24 1 

Northern Resident ............. -; N 302 (n/a; 2018) ......... 2.2 0.2 

Family Phocoenidae (porpoises): 

Harbor porpoise .......... Phocoena phocoena 

vomerina.

Southeast Alaska * ............. -; Y Unknown ................... 8,091 Undet. 34 

Dall’s porpoise ............ Phocoenoides dalli dalli ..... Alaska 6 .............................. -; N 83,400 (0.097; n/a; 

1991).

5,303 Undet. 38 

Order Carnivora—Superfamily Pinnipedia 

Family Otariidae (eared 

seals and sea lions): 

Northern fur seal ......... Callorhinus ursinus ............ Pribilof Islands/Eastern Pacific.D; Y 608,143 (0.2; 

514,738; 2018).

........................ 11,067 387 

California sea lion ....... Zalophus californianus ....... United States ..................... -/-; N 257,606 (N/A, 

233,515, 2014).

........................ 14,011 ≥321 

Steller sea lion ............ Eumetopias jubatus 

jubatus.

Western U.S. * ................... E/D; Y 52,932 (n/a; 2019) .... 15,348 318 255 

E. j. monteriensis ............... Eastern U.S. * .................... -/-; N 43,201 (n/a; 2017) .... 2,592 112 

Family Phocidae (earless 

seals): 

Harbor seal ................. Phoca vitulina richardii ...... Sitka/Chatham Strait .......... -; N 13,289 (n/a; 11,883; 

2015).

24,916 356 77 

Dixon/Cape Decision ......... -; N 23,478 (n/a; 21,453; 

2015).

644 69 

Clarence Strait ................... -; N 27,659 (n/a; 24,854; 

2015).

746 40 

Northern elephant seal Mirounga angustirostris ..... California Breeding ............ -; N 179,000 (n/a; 81,368; 

2010).

........................ 4,882 8.8 

* Stocks marked with an asterisk are addressed in further detail in text below. 

1Endangered 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. 2 NMFS marine mammal stock assessment reports at: www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable. For most stocks of killer whales, the abundance values represent direct counts of individually identifiable animals; therefore there is only a single abundance estimate with no associated CV. For certain stocks of pinnipeds, 

abundance estimates are based upon observations of animals (often pups) ashore multiplied by some correction factor derived from knowledge of the species’ (or 

similar species’) life history to arrive at a best abundance estimate; therefore, there is no associated CV. In these cases, the minimum abundance may represent actual counts of all animals ashore. 3Total abundance estimates for animals in British Columbia based on surveys of the Strait of Georgia, Johnstone Strait, Queen Charlotte Sound, Hecate Strait, and 

Dixon Entrance. This column represents estimated abundance of animals in British Columbia, where available, but does not necessarily represent additional stocks. 

Please see Best et al. (2015) and Pitcher et al. (2007) for additional information. 4These values, found in NMFS’s SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial fisheries, subsistence hunting, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value. All M/SI values are 

as presented in the draft 2020 SARs. 5Transient and resident killer whales are considered unnamed subspecies (Committee on Taxonomy, 2020). 

6Abundance estimates for these stocks are not considered current. PBR is therefore considered undetermined for these stocks, as there is no current minimum 

abundance estimate for use in calculation. We nevertheless present the most recent abundance estimates, as these represent the best available information for use 

in this document. 7This stock is known to spend a portion of time outside the U.S. EEZ. Therefore, the PBR presented here is the allocation for U.S. waters only and is a portion of 

the total. The total PBR for blue whales is 2.1 (7/12 allocation for U.S. waters). Annual M/SI presented for these species is for U.S. waters only. 

Table 1 denotes the status of species 

and stocks under the U.S. MMPA and 

ESA. We note also that under Canada’s 

Species at Risk Act, the sei whale and 

blue whale are listed as endangered; the 

fin whale and northern resident, 

offshore, and transient populations of 

killer whales are listed as threatened; 

and the humpback whale, harbor 

porpoise, and Steller sea lion are 

considered species of special concern. 

Two populations of gray whales are 

recognized, eastern and western North 

Pacific (ENP and WNP). WNP whales 

are known to feed in the Okhotsk Sea 

and off of Kamchatka before migrating 

south to poorly known wintering 

grounds, possibly in the South China 

Sea. The two populations have 

historically been considered 

geographically isolated from each other; 

however, data from satellite-tracked 

whales indicate that there is some 

overlap between the stocks. Two WNP 

whales were tracked from Russian 

foraging areas along the Pacific rim to 

Baja California (Mate et al., 2011), and, 

in one case where the satellite tag 

remained attached to the whale for a 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30013 

longer period, a WNP whale was tracked 

from Russia to Mexico and back again 

(IWC, 2012). A number of whales are 

known to have occurred in the eastern 

Pacific through comparisons of ENP and 

WNP photo-identification catalogs 

(IWC, 2012; Weller et al., 2011; Burdin 

et al., 2011). Therefore, a portion of the 

WNP population is assumed to migrate, 

at least in some years, to the eastern 

Pacific during the winter breeding 

season. Based on guidance provided 

through interagency consultation under 

section 7 of the ESA, approximately 0.1 

percent of gray whales occurring in 

southeast Alaska and northern British 

Columbia are likely to be from the 

Western North Pacific stock; the rest 

would be from the Eastern North Pacific 

stock. 

Prior to 2016, humpback whales were 

listed under the ESA as an endangered 

species worldwide. Following a 2015 

global status review (Bettridge et al., 

2015), NMFS delineated 14 distinct 

population segments (DPS) with 

different listing statuses (81 FR 62259; 

September 8, 2016) pursuant to the ESA. 

The DPSs that occur in U.S. waters do 

not necessarily equate to the existing 

stocks designated under the MMPA and 

shown in Table 1. 

In the eastern North Pacific, three 

humpback whale DPSs may occur: The 

Hawaii DPS (not listed), Mexico DPS 

(threatened), and Central America DPS 

(endangered). Individuals encountered 

in the proposed survey area would 

likely be from the Hawaii DPS, followed 

by the Mexico DPS; individuals from 

the Central America DPS are unlikely to 

feed in northern British Columbia and 

Southeast Alaska (Ford et al., 2014). 

According to Wade (2017), in southeast 

Alaska and northern British Columbia, 

encountered whales are most likely to 

be from the Hawaii DPS (96.1 percent), 

but could be from the Mexico DPS (3.8 

percent). 

Although no comprehensive 

abundance estimate is available for the 

Alaska stock of minke whales, recent 

surveys provide estimates for portions 

of the stock’s range. A 2010 survey 

conducted on the eastern Bering Sea 

shelf produced a provisional abundance 

estimate of 2,020 (CV = 0.73) whales 

(Friday et al., 2013). This estimate is 

considered provisional because it has 

not been corrected for animals missed 

on the trackline, animals submerged 

when the ship passed, or responsive 

movement. Additionally, line-transect 

surveys were conducted in shelf and 

nearshore waters (within 30–45 nautical 

miles of land) in 2001–2003 between the 

Kenai Peninsula (150° W) and Amchitka 

Pass (178° W). Minke whale abundance 

was estimated to be 1,233 (CV = 0.34) 

for this area (also not been corrected for 

animals missed on the trackline) 

(Zerbini et al., 2006). The majority of the 

sightings were in the Aleutian Islands, 

rather than in the Gulf of Alaska, and in 

water shallower than 200 m. These 

estimates cannot be used as an estimate 

of the entire Alaska stock of minke 

whales because only a portion of the 

stock’s range was surveyed. Similarly, 

although a comprehensive abundance 

estimate is not available for the 

northeast Pacific stock of fin whales, 

provisional estimates representing 

portions of the range are available. The 

same 2010 survey of the eastern Bering 

Sea shelf provided an estimate of 1,061 

(CV = 0.38) fin whales (Friday et al., 

2013). The estimate is not corrected for 

missed animals, but is expected to be 

robust as previous studies have shown 

that only small correction factors are 

needed for fin whales (Barlow, 1995). 

Zerbini et al. (2006) produced an 

estimate of 1,652 (95 percent CI: 1,142– 

2,389) fin whales for the area described 

above. 

Current and historical estimates of the 

abundance of sperm whales in the North 

Pacific are considered unreliable, and 

caution should be exercised in 

interpreting published estimates (Muto 

et al., 2017). However, Kato and 

Miyashita (1998) produced an 

abundance estimate of 102,112 (CV = 

0.155) sperm whales in the western 

North Pacific (believed to be positively 

biased). The number of sperm whales 

occurring within Alaska waters is 

unknown. 

Very little information is available 

regarding beaked whale stocks in 

Alaska, with no reliable abundance 

estimates available for any stock. 

Sightings of all beaked whale species 

are rare in Alaska, and their presence 

and distribution have mostly been 

inferred from stranding data. During 

long-term passive acoustic monitoring 

conducted at five sites in the Gulf of 

Alaska from 2011–15, all three species 

were detected at three sites located on 

the continental slope and offshore 

seamounts (Rice et al., 2021). There was 

no clear diel or interannual pattern for 

any species at any site. However, a 

different species was predominant at 

each site and, when detected at the 

same locations, detection peaks were all 

seasonally offset, demonstrating some 

degree of habitat partitioning. The 

authors noted that detections for all 

three beaked whale species were low 

throughout the summer. Stranding 

records exist for all three species of 

beaked whale in the survey area. 

Using 2010–2012 survey data for the 

inland waters of southeast Alaska, 

Dahlheim et al. (2015) calculated a 

combined abundance estimate for 

harbor porpoise in the northern 

(including Cross Sound, Icy Strait, 

Glacier Bay, Lynn Canal, Stephens 

Passage, and Chatham Strait) and 

southern (including Frederick Sound, 

Sumner Strait, Wrangell and Zarembo 

Islands, and Clarence Strait as far south 

as Ketchikan) regions of the inland 

waters of 975 (95 percent CI = 857– 

1,109). This abundance estimate was 

subsequently corrected for detection 

biases, which are expected to be high for 

harbor porpoise (Muto et al., 2020). The 

resulting abundance estimates are 553 

harbor porpoise (CV = 0.13) in the 

northern inland waters and 801 harbor 

porpoise (CV = 0.15) in the southern 

inland waters (Muto et al., 2020). 

The Steller sea lion ranges from Japan, 

through the Okhotsk and Bering Seas, to 

central California. It consists of two 

morphologically, ecologically, and 

behaviorally separate DPSs: The 

Eastern, which includes sea lions in 

southeast Alaska, British Columbia, 

Washington, Oregon, and California; 

and the Western, which includes sea 

lions in all other regions of Alaska, as 

well as Russia and Japan. At the time of 

their initial listing under the ESA, 

Steller sea lions were considered a 

single population listed as threatened. 

In 1997, following a status review, 

NMFS established two DPSs of Steller 

sea lions, and issued a final 

determination to list the Western DPS as 

endangered under the ESA. The Eastern 

DPS of Steller sea lion was delisted in 

2013. According to Hastings et al. 

(2020), approximately 2.2 percent of 

Steller sea lions occurring in the 

proposed action area are likely to be 

from the Western DPS; the rest would be 

from the Eastern DPS. 

Important Habitat 

Several biologically important areas 

(BIA) for marine mammals are 

recognized in southeast Alaska, and 

critical habitat is designated in 

southeast Alaska for the Steller sea lion 

(58 FR 45269; August 27, 1993) and the 

Mexico DPS of humpback whale (86 FR 

21082; April 21, 2021). Note that 

although the eastern DPS of Steller sea 

lion was delisted in 2013, the change in 

listing status does not affect the 

designated critical habitat. Critical 

habitat is defined by section 3 of the 

ESA as (1) the specific areas within the 

geographical area occupied by the 

species, at the time it is listed, on which 

are found those physical or biological 

features (a) essential to the conservation 

of the species and (b) which may require 

special management considerations or 

protection; and (2) specific areas outside 

the geographical area occupied by the 

30014 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

species at the time it is listed, upon a 

determination by the Secretary that such 

areas are essential for the conservation 

of the species. 

Mexico DPS humpback whale critical 

habitat includes marine waters in 

Washington, Oregon, California, and 

Alaska. Only the areas designated in 

southeast Alaska fall within the survey 

area. The relevant designated critical 

habitat (Unit 10) extends from 139°24′ 

W, southeastward to the U.S. border 

with Canada. The area also extends 

offshore to a boundary drawn along the 

2,000-m isobath. The essential feature 

for Mexico DPS humpback whale 

critical habitat is prey species, primarily 

euphausiids and small pelagic schooling 

fishes of sufficient quality, abundance, 

and accessibility within humpback 

whale feeding areas to support feeding 

and population growth. This area was 

drawn to encompass well-established 

feeding grounds in southeast Alaska and 

an identified feeding BIA (86 FR 21082; 

April 21, 2021). Humpback whales 

occur year-round in this unit, with 

highest densities occurring in summer 

and fall (Baker et al., 1985, 1986). 

Critical habitat for humpback whales 

has been designated under Canadian 

law in four locations in British 

Columbia (DFO, 2013), including in the 

waters of the survey area off Haida 

Gwaii (Langara Island and Southeast 

Moresby Island). These areas show 

persistent aggregations of humpback 

whales and have features such as prey 

availability, suitable acoustic 

environment, water quality, and 

physical space that allow for feeding, 

foraging, socializing, and resting (DFO, 

2013). 

Designated Steller sea lion critical 

habitat includes terrestrial, aquatic, and 

air zones that extend 3,000 ft (0.9 km) 

landward, seaward, and above each 

major rookery and major haul-out in 

Alaska. Within the survey area, critical 

habitat is located on islands off the coast 

of southeast Alaska (e.g., Sitka, 

Coronation Island, Noyes Island, and 

Forrester Island). The physical and 

biological features identified for the 

aquatic areas of Steller sea lion 

designated critical habitat that occur 

within the survey area are those that 

support foraging, such as adequate prey 

resources and available foraging habitat. 

The proposed survey tracklines do not 

directly overlap any areas of Steller sea 

lion critical habitat, though the extent of 

the estimated ensonified area associated 

with the survey would overlap with 

units of Steller sea lion critical habitat. 

However, the brief duration of 

ensonification for any critical habitat 

unit leads us to conclude that any 

impacts on Steller sea lion habitat 

would be insignificant and would not 

affect the conservation value of the 

critical habitat. 

For humpback whales, seasonal 

feeding BIAs for spring (March–May), 

summer (June–August), and fall 

(September–November) are recognized 

in southeast Alaska (Ferguson et al., 

2015). It should be noted that the 

aforementioned designated critical 

habitat in the survey area was based in 

large part on the same information that 

informed an understanding of the BIAs. 

Though the BIAs are not synonymous 

with critical habitat designated under 

the ESA, they were regarded by the 

humpback whale critical habitat review 

team as an important source of 

information and informative to their 

review of areas that meet the definition 

of critical habitat for humpback whales 

(86 FR 21082; April 21, 2021). The 

aforementioned southeast Alaska unit of 

designated critical habitat encompasses 

the BIAs, with the offshore and 

nearshore boundaries corresponding 

with the BIA boundary. 

A separate feeding BIA is recognized 

in southeast Alaska for gray whales. 

Once considered only a migratory 

pathway, the Gulf of Alaska is now 

known to provide foraging and 

overwintering habitat for ENP gray 

whales (Ferguson et al., 2015). Based on 

the regular occurrence of feeding gray 

whales (including repeat sightings of 

individuals across years) off southeast 

Alaska, an area off of Sitka is 

recognized. The greatest densities of 

gray whales on the feeding area in 

southeast Alaska occur from May to 

November. However, this area is located 

to the north of the proposed survey area 

and would not be expected to be 

meaningfully impacted by the survey 

activities. A separate migratory BIA is 

recognized as extending along the 

continental shelf throughout the Gulf of 

Alaska. During their annual migration, 

most gray whales pass through the Gulf 

of Alaska in the fall (November through 

January; southbound) and again in the 

spring (March through May; 

northbound) (Ferguson et al., 2015). 

Therefore, the planned survey would 

not be expected to impact gray whale 

migratory habitat due to the timing of 

the survey in late summer. No important 

behaviors of gray whales in either the 

feeding or migratory BIAs are expected 

to be affected. For more information on 

BIAs, please see Ferguson et al. (2015) 

or visit https://oceannoise.noaa.gov/ 

biologically-important-areas. 

Unusual Mortality Events (UME) 

A UME is defined under the MMPA 

as ‘‘a stranding that is unexpected; 

involves a significant die-off of any 

marine mammal population; and 

demands immediate response.’’ For 

more information on UMEs, please visit: 

www.fisheries.noaa.gov/national/ 

marine-mammal-protection/marinemammal-unusual-mortality-events. 

There is a currently ongoing UME 

affecting gray whales throughout their 

migratory range. 

Since January 1, 2019, elevated gray 

whale strandings have occurred along 

the west coast of North America from 

Mexico through Alaska. As of May 6, 

2021, there have been a total of 454 

whales reported in the event, with 

approximately 218 dead whales in 

Mexico, 218 whales in the United States 

(62 in California; 10 in Oregon; 53 in 

Washington, 93 in Alaska), and 18 

whales in British Columbia, Canada. For 

the United States, the historical 18-year 

5-month average (Jan–May) is 14.8 

whales for the four states for this same 

time-period. Several dead whales have 

been emaciated with moderate to heavy 

whale lice (cyamid) loads. Necropsies 

have been conducted on a subset of 

whales with additional findings of 

vessel strike in three whales and 

entanglement in one whale. In Mexico, 

50–55 percent of the free-ranging whales 

observed in the lagoons in winter have 

been reported as ‘‘skinny’’ compared to 

the annual average of 10–12 percent 

‘‘skinny’’ whales normally seen. The 

cause of the UME is as yet 

undetermined. For more information, 

please visit: www.fisheries.noaa.gov/ 

national/marine-life-distress/2019– 

2020-gray-whale-unusual-mortalityevent-along-west-coast-and. 

Another recent, notable UME 

involved large whales and occurred in 

the western Gulf of Alaska and off of 

British Columbia, Canada. Beginning in 

May 2015, elevated large whale 

mortalities (primarily fin and humpback 

whales) occurred in the areas around 

Kodiak Island, Afognak Island, Chirikof 

Island, the Semidi Islands, and the 

southern shoreline of the Alaska 

Peninsula. Although most carcasses 

have been non-retrievable as they were 

discovered floating and in a state of 

moderate to severe decomposition, the 

UME is likely attributable to ecological 

factors, i.e., the 2015 El Nin ̃ o, ‘‘warm 

water blob,’’ and the Pacific Coast 

domoic acid bloom. The UME was 

closed in 2016. More information is 

available online at 

www.fisheries.noaa.gov/national/ 

marine-life-distress/2015–2016-largewhale-unusual-mortality-event-westerngulf-alaska. 

Marine Mammal Hearing 

Hearing is the most important sensory 

modality for marine mammals 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30015 

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. Current data indicate 

that 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) 

recommended that marine mammals be 

divided into functional hearing groups 

based on directly measured or estimated 

hearing ranges on the basis of available 

behavioral response data, audiograms 

derived using auditory evoked potential 

techniques, anatomical modeling, and 

other data. Note that no direct 

measurements of hearing ability have 

been successfully completed for 

mysticetes (i.e., low-frequency 

cetaceans). Subsequently, NMFS (2018) 

described generalized hearing ranges for 

these marine mammal hearing groups. 

Generalized hearing ranges were chosen 

based on the approximately 65 decibel 

(dB) threshold from the normalized 

composite audiograms, with the 

exception for lower limits for lowfrequency cetaceans where the lower 

bound was deemed to be biologically 

implausible and the lower bound from 

Southall et al. (2007) retained. Marine 

mammal hearing groups and their 

associated hearing ranges are provided 

in Table 2. 

TABLE 2—MARINE MAMMAL HEARING GROUPS

[NMFS, 2018] 

Hearing group Generalized hearing 

range * 

Low-frequency (LF) cetaceans (baleen whales) ................................................................................................................. 7 Hz to 35 kHz. 

Mid-frequency (MF) cetaceans (dolphins, toothed whales, beaked whales, bottlenose whales) ...................................... 150 Hz to 160 kHz. 

High-frequency (HF) cetaceans (true porpoises, Kogia, river dolphins, cephalorhynchid, Lagenorhynchus cruciger & L. 

australis).

275 Hz to 160 kHz. 

Phocid pinnipeds (PW) (underwater) (true seals) .............................................................................................................. 50 Hz to 86 kHz. 

Otariid pinnipeds (OW) (underwater) (sea lions and fur seals) .......................................................................................... 60 Hz to 39 kHz. 

* 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 ∼65 dB threshold from normalized composite audiogram, 

with the exception for lower limits for LF cetaceans (Southall et al. 2007) and PW pinniped (approximation). 

The pinniped functional hearing 

group was modified from Southall et al. 

(2007) on the basis of data indicating 

that phocid species have consistently 

demonstrated an extended frequency 

range of hearing compared to otariids, 

especially in the higher frequency range 

(Hemila ̈ et al., 2006; Kastelein et al., 

2009; Reichmuth and Holt, 2013). 

For more detail concerning these 

groups and associated frequency ranges, 

please see NMFS (2018) for a review of 

available information. Twenty-one 

marine mammal species (16 cetacean 

and 5 pinniped (3 otariid and 2 phocid) 

species) are considered herein. Of the 

cetacean species that may be present, 

six are classified as low-frequency 

cetaceans (i.e., all mysticete species), 

eight are classified as mid-frequency 

cetaceans (i.e., all delphinid and ziphiid 

species and the sperm whale), and two 

are classified as high-frequency 

cetaceans (i.e., porpoises). 

Potential Effects of Specified Activities 

on Marine Mammals and Their Habitat 

This section includes a summary of 

the ways that L–DEO’s specified activity 

may impact marine mammals and their 

habitat. Detailed descriptions of the 

potential effects of similar specified 

activities have been provided in other 

recent Federal Register notices, 

including for survey activities using the 

same methodology and over a similar 

amount of time, and affecting similar 

species (e.g., 83 FR 29212, June 22, 

2018; 84 FR 14200, April 9, 2019; 85 FR 

19580, April 7, 2020). No significant 

new information is available, and we 

refer the reader to these documents for 

additional detail. The Estimated Take 

section includes a quantitative analysis 

of the number of individuals that are 

expected to be taken by L–DEO’s 

activity. The Negligible Impact Analysis 

and Determination section considers the 

potential effects of the specified activity, 

the Estimated Take section, and the 

Proposed Mitigation section, to draw 

conclusions regarding the likely impacts 

of these activities on the reproductive 

success or survivorship of individuals 

and how those impacts on individuals 

are likely to impact marine mammal 

species or stocks. 

Background on Active Acoustic Sound 

Sources and Acoustic Terminology 

This section contains a brief technical 

background on sound, on the 

characteristics of certain sound types, 

and on metrics used in this proposal 

inasmuch as the information is relevant 

to the specified activity and to the 

discussion of the effects of the specified 

activity on marine mammals in this 

document. For general information on 

sound and its interaction with the 

marine environment, please see, e.g., Au 

and Hastings (2008); Richardson et al. 

(1995); Urick (1983). 

Sound travels in waves, the basic 

components of which are frequency, 

wavelength, velocity, and amplitude. 

Frequency is the number of pressure 

waves that pass by a reference point per 

unit of time and is measured in hertz or 

cycles per second. Wavelength is the 

distance between two peaks or 

corresponding points of a sound wave 

(length of one cycle). Higher frequency 

sounds have shorter wavelengths than 

lower frequency sounds, and typically 

attenuate (decrease) more rapidly, 

except in certain cases in shallower 

water. Amplitude is the height of the 

sound pressure wave or the ‘‘loudness’’ 

of a sound and is typically described 

using the relative unit of the decibel. A 

sound pressure level (SPL) in dB is 

described as the ratio between a 

measured pressure and a reference 

pressure (for underwater sound, this is 

1 microPascal (mPa)), and is a 

logarithmic unit that accounts for large 

variations in amplitude. Therefore, a 

relatively small change in dB 

corresponds to large changes in sound 

pressure. The source level (SL) 

represents the SPL referenced at a 

distance of 1 m from the source 

(referenced to 1 mPa), while the received 

level is the SPL at the listener’s position 

(referenced to 1 mPa). 

Root mean square (rms) is the 

quadratic mean sound pressure over the 

duration of an impulse. Root mean 

square is calculated by squaring all of 

the sound amplitudes, averaging the 

squares, and then taking the square root 

of the average (Urick, 1983). Root mean 

square accounts for both positive and 

negative values; squaring the pressures 

makes all values positive so that they 

30016 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

may be accounted for in the summation 

of pressure levels (Hastings and Popper, 

2005). This measurement is often used 

in the context of discussing behavioral 

effects, in part because behavioral 

effects, which often result from auditory 

cues, may be better expressed through 

averaged units than by peak pressures. 

Sound exposure level (SEL; 

represented as dB re 1 mPa2-s) 

represents the total energy in a stated 

frequency band over a stated time 

interval or event and considers both 

intensity and duration of exposure. The 

per-pulse SEL is calculated over the 

time window containing the entire 

pulse (i.e., 100 percent of the acoustic 

energy). SEL is a cumulative metric; it 

can be accumulated over a single pulse, 

or calculated over periods containing 

multiple pulses. Cumulative SEL 

represents the total energy accumulated 

by a receiver over a defined time 

window or during an event. Peak sound 

pressure (also referred to as zero-to-peak 

sound pressure or 0-pk) is the maximum 

instantaneous sound pressure 

measurable in the water at a specified 

distance from the source and is 

represented in the same units as the rms 

sound pressure. 

When underwater objects vibrate or 

activity occurs, sound-pressure waves 

are created. These waves alternately 

compress and decompress the water as 

the sound wave travels. Underwater 

sound waves radiate in a manner similar 

to ripples on the surface of a pond and 

may be either directed in a beam or 

beams or may radiate in all directions 

(omnidirectional sources), as is the case 

for sound produced by the pile driving 

activity considered here. The 

compressions and decompressions 

associated with sound waves are 

detected as changes in pressure by 

aquatic life and man-made sound 

receptors such as hydrophones. 

Even in the absence of sound from the 

specified activity, the underwater 

environment is typically loud due to 

ambient sound, which is defined as 

environmental background sound levels 

lacking a single source or point 

(Richardson et al., 1995). The sound 

level of a region is defined by the total 

acoustical energy being generated by 

known and unknown sources. These 

sources may include physical (e.g., 

wind and waves, earthquakes, ice, 

atmospheric sound), biological (e.g., 

sounds produced by marine mammals, 

fish, and invertebrates), and 

anthropogenic (e.g., vessels, dredging, 

construction) sound. A number of 

sources contribute to ambient sound, 

including wind and waves, which are a 

main source of naturally occurring 

ambient sound for frequencies between 

200 hertz (Hz) and 50 kilohertz (kHz) 

(Mitson, 1995). In general, ambient 

sound levels tend to increase with 

increasing wind speed and wave height. 

Precipitation can become an important 

component of total sound at frequencies 

above 500 Hz, and possibly down to 100 

Hz during quiet times. Marine mammals 

can contribute significantly to ambient 

sound levels, as can some fish and 

snapping shrimp. The frequency band 

for biological contributions is from 

approximately 12 Hz to over 100 kHz. 

Sources of ambient sound related to 

human activity include transportation 

(surface vessels), dredging and 

construction, oil and gas drilling and 

production, geophysical surveys, sonar, 

and explosions. Vessel noise typically 

dominates the total ambient sound for 

frequencies between 20 and 300 Hz. In 

general, the frequencies of 

anthropogenic sounds are below 1 kHz 

and, if higher frequency sound levels 

are created, they attenuate rapidly. 

The sum of the various natural and 

anthropogenic sound sources that 

comprise ambient sound at any given 

location and time depends not only on 

the source levels (as determined by 

current weather conditions and levels of 

biological and human 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 

activity may be a negligible addition to 

the local environment or could form a 

distinctive signal that may affect marine 

mammals. Details of source types are 

described in the following text. 

Sounds are often considered to fall 

into one of two general types: Pulsed 

and non-pulsed (defined in the 

following). The distinction between 

these two sound types is important 

because they have differing potential to 

cause physical effects, particularly with 

regard to hearing (e.g., Ward, 1997 in 

Southall et al., 2007). Please see 

Southall et al. (2007) for an in-depth 

discussion of these concepts. The 

distinction between these two sound 

types is not always obvious, as certain 

signals share properties of both pulsed 

and non-pulsed sounds. A signal near a 

source could be categorized as a pulse, 

but due to propagation effects as it 

moves farther from the source, the 

signal duration becomes longer (e.g., 

Greene and Richardson, 1988). 

Pulsed sound sources (e.g., airguns, 

explosions, gunshots, sonic booms, 

impact pile driving) produce signals 

that are brief (typically considered to be 

less than one second), broadband, atonal 

transients (ANSI, 1986, 2005; Harris, 

1998; NIOSH, 1998; ISO, 2003) and 

occur either as isolated events or 

repeated in some succession. Pulsed 

sounds are all characterized by a 

relatively rapid rise from ambient 

pressure to a maximal pressure value 

followed by a rapid decay period that 

may include a period of diminishing, 

oscillating maximal and minimal 

pressures, and generally have an 

increased capacity to induce physical 

injury as compared with sounds that 

lack these features. 

Non-pulsed sounds can be tonal, 

narrowband, or broadband, brief or 

prolonged, and may be either 

continuous or intermittent (ANSI, 1995; 

NIOSH, 1998). Some of these nonpulsed sounds can be transient signals 

of short duration but without the 

essential properties of pulses (e.g., rapid 

rise time). Examples of non-pulsed 

sounds include those produced by 

vessels, aircraft, machinery operations 

such as drilling or dredging, vibratory 

pile driving, and active sonar systems. 

The duration of such sounds, as 

received at a distance, can be greatly 

extended in a highly reverberant 

environment. 

Airgun arrays produce pulsed signals 

with energy in a frequency range from 

about 10–2,000 Hz, with most energy 

radiated at frequencies below 200 Hz. 

The amplitude of the acoustic wave 

emitted from the source is equal in all 

directions (i.e., omnidirectional), but 

airgun arrays do possess some 

directionality due to different phase 

delays between guns in different 

directions. Airgun arrays are typically 

tuned to maximize functionality for data 

acquisition purposes, meaning that 

sound transmitted in horizontal 

directions and at higher frequencies is 

minimized to the extent possible. 

Summary on Specific Potential Effects 

of Acoustic Sound Sources 

Underwater sound from active 

acoustic sources can include one or 

more of the following: Temporary or 

permanent hearing impairment, nonauditory physical or physiological 

effects, behavioral disturbance, stress, 

and masking. The degree of effect is 

intrinsically related to the signal 

characteristics, received level, distance 

from the source, and duration of the 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30017 

sound exposure. Marine mammals 

exposed to high-intensity sound, or to 

lower-intensity sound for prolonged 

periods, can experience hearing 

threshold shift (TS), which is the loss of 

hearing sensitivity at certain frequency 

ranges (Finneran, 2015). TS can be 

permanent (PTS), in which case the loss 

of hearing sensitivity is not fully 

recoverable, or temporary (TTS), in 

which case the animal’s hearing 

threshold would recover over time 

(Southall et al., 2007). 

Due to the characteristics of airgun 

arrays as a distributed sound source, 

maximum estimated Level A 

harassment isopleths for species of 

certain hearing groups are assumed to 

fall within the near field of the array. 

For these species, i.e., mid-frequency 

cetaceans and all pinnipeds, animals in 

the vicinity of L–DEO’s proposed 

seismic survey activity are unlikely to 

incur PTS. For low-frequency cetaceans 

and high-frequency cetaceans, potential 

exposures sufficient to cause low-level 

PTS may occur on the basis of 

cumulative exposure level and 

instantaneous exposure to peak pressure 

levels, respectively. However, when 

considered in conjunction with the 

potential for aversive behavior, relative 

motion of the exposed animal and the 

sound source, and the anticipated 

efficacy of the proposed mitigation 

requirements, a reasonable conclusion 

may be drawn that PTS is not a likely 

outcome for any species. However, we 

propose to authorize take by Level A 

harassment, where indicated by the 

quantitative exposure analysis, for 

species from the low- and highfrequency cetacean hearing groups. 

Please see Estimated Take and Proposed 

Mitigation for further discussion. 

Behavioral disturbance may include a 

variety of effects, including subtle 

changes in behavior (e.g., minor or brief 

avoidance of an area or changes in 

vocalizations), more conspicuous 

changes in similar behavioral activities, 

and more sustained and/or potentially 

severe reactions, such as displacement 

from or abandonment of high-quality 

habitat. Behavioral responses to sound 

are highly variable and context-specific 

and any reactions depend on numerous 

intrinsic and extrinsic factors (e.g., 

species, state of maturity, experience, 

current activity, reproductive state, 

auditory sensitivity, time of day), as 

well as the interplay between factors. 

Available studies show wide variation 

in response to underwater sound; 

therefore, it is difficult to predict 

specifically how any given sound in a 

particular instance might affect marine 

mammals perceiving the signal. 

In addition, sound can disrupt 

behavior through masking, or interfering 

with, an animal’s ability to detect, 

recognize, or discriminate between 

acoustic signals of interest (e.g., those 

used for intraspecific communication 

and social interactions, prey detection, 

predator avoidance, navigation). 

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 sound is natural 

(e.g., snapping shrimp, wind, waves, 

precipitation) or anthropogenic (e.g., 

shipping, sonar, seismic exploration) in 

origin. 

Sound may affect marine mammals 

through impacts on the abundance, 

behavior, or distribution of prey species 

(e.g., crustaceans, cephalopods, fish, 

zooplankton) (i.e., effects to marine 

mammal habitat). 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. The most likely impacts 

(if any) for most prey species in a given 

area would be temporary avoidance of 

the area. Surveys using active acoustic 

sound sources move through an area 

relatively quickly, limiting exposure to 

multiple pulses. 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. Finally, the survey equipment 

will not have significant impacts to the 

seafloor and does not represent a source 

of pollution. 

Vessel Strike 

Vessel collisions with marine 

mammals, or ship strikes, can result in 

death or serious injury of the animal. 

These interactions are typically 

associated with large whales, which are 

less maneuverable than are smaller 

cetaceans or pinnipeds in relation to 

large vessels. The severity of injuries 

typically depends on the size and speed 

of the vessel, with the probability of 

death or serious injury increasing as 

vessel speed increases (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 chances 

of a lethal injury decline from 

approximately 80 percent at 15 kn to 

approximately 20 percent at 8.6 kn. At 

speeds below 11.8 kn, the chances of 

lethal injury drop below 50 percent 

(Vanderlaan and Taggart, 2007). 

Ship strikes generally involve 

commercial shipping, which is much 

more common in both space and time 

than is geophysical survey activity and 

which typically involves larger vessels 

moving at faster speeds. Jensen and 

Silber (2004) summarized ship strikes of 

large whales worldwide from 1975– 

2003 and found that most collisions 

occurred in the open ocean and 

involved large vessels (e.g., commercial 

shipping). Commercial fishing vessels 

were responsible for 3 percent of 

recorded collisions, while no such 

incidents were reported for geophysical 

survey vessels during that time period. 

For vessels used in geophysical 

survey activities, vessel speed while 

towing gear is typically only 4–5 kn. At 

these speeds, both the possibility of 

striking a marine mammal and the 

possibility of a strike resulting in 

serious injury or mortality are so low as 

to be discountable. At average transit 

speed for geophysical survey vessels 

(approximately 10 kn), the probability of 

serious injury or mortality resulting 

from a strike (if it occurred) is less than 

50 percent (Vanderlaan and Taggart, 

2007; Conn and Silber, 2013). However, 

the likelihood of a strike actually 

happening is again low given the 

smaller size of these vessels and 

generally slower speeds. We anticipate 

that vessel collisions involving seismic 

data acquisition vessels towing gear, 

while not impossible, represent 

unlikely, unpredictable events for 

which there are no preventive measures. 

Given the required mitigation measures, 

the relatively slow speeds of vessels 

towing gear, the presence of bridge crew 

watching for obstacles at all times 

(including marine mammals), the 

presence of marine mammal observers, 

and the small number of seismic survey 

cruises relative to commercial ship 

traffic, we believe that the possibility of 

ship strike is discountable and, further, 

that were a strike of a large whale to 

occur, it would be unlikely to result in 

serious injury or mortality. No 

incidental take resulting from ship 

strike is anticipated or proposed for 

authorization, and this potential effect 

of the specified activity will not be 

discussed further in the following 

analysis. 

The potential effects of L–DEO’s 

specified survey activity are expected to 

be limited to Level B harassment 

consisting of behavioral harassment 

and/or temporary auditory effects and, 

for certain species of low- and highfrequency cetaceans only, low-level 

permanent auditory effects. No 

permanent auditory effects for any 

species belonging to other hearing 

groups, or significant impacts to marine 

30018 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

mammal habitat, including prey, are 

expected. 

Estimated Take 

This section provides an estimate of 

the number of incidental takes proposed 

for authorization through this IHA, 

which will inform both NMFS’ 

consideration of ‘‘small numbers’’ and 

the negligible impact determination. 

Harassment is the only type of take 

expected to result from these activities. 

Except with respect to certain activities 

not pertinent here, section 3(18) of the 

MMPA defines ‘‘harassment’’ as any act 

of pursuit, torment, or annoyance, 

which (i) has the potential to injure a 

marine mammal or marine mammal 

stock in the wild (Level A harassment); 

or (ii) has the potential to disturb a 

marine mammal or marine mammal 

stock in the wild by causing disruption 

of behavioral patterns, including, but 

not limited to, migration, breathing, 

nursing, breeding, feeding, or sheltering 

(Level B harassment). 

Authorized takes would primarily be 

by Level B harassment, as use of seismic 

airguns has the potential to result in 

disruption of behavioral patterns or 

temporary auditory effects for 

individual marine mammals. There is 

also some potential for auditory injury 

(Level A harassment) for low-frequency 

(i.e., mysticetes) and high-frequency 

cetaceans (i.e., porpoises). The proposed 

mitigation and monitoring measures are 

expected to minimize the severity of 

such taking to the extent practicable. 

As described previously, no serious 

injury or mortality is anticipated or 

proposed to be authorized for this 

activity. Below we describe how the 

take is estimated. 

Generally speaking, we estimate take 

by considering: (1) Acoustic thresholds 

above which NMFS believes the best 

available science indicates marine 

mammals will be behaviorally harassed 

or incur some degree of permanent 

hearing impairment; (2) the area or 

volume of water that will be ensonified 

above these levels in a day; (3) the 

density or occurrence of marine 

mammals within these ensonified areas; 

and, (4) and the number of days of 

activities. We note that while these 

basic factors can contribute to a basic 

calculation to provide an initial 

prediction of takes, additional 

information that can qualitatively 

inform take estimates is also sometimes 

available (e.g., previous monitoring 

results or average group size). Below, we 

describe the factors considered here in 

more detail and present the proposed 

take estimate. 

Acoustic Thresholds 

NMFS uses acoustic thresholds that 

identify the received level of 

underwater sound above which exposed 

marine mammals would be reasonably 

expected to be behaviorally harassed 

(equated to Level B harassment) or to 

incur PTS of some degree (equated to 

Level A harassment). 

Level B Harassment—Though 

significantly driven by received level, 

the onset of behavioral disturbance from 

anthropogenic noise exposure is also 

informed to varying degrees by other 

factors related to the source (e.g., 

frequency, predictability, duty cycle), 

the environment (e.g., bathymetry), and 

the receiving animals (hearing, 

motivation, experience, demography, 

behavioral context) and can be difficult 

to predict (Southall et al., 2007, Ellison 

et al., 2012). NMFS uses a generalized 

acoustic threshold based on received 

level to estimate the onset of behavioral 

harassment. NMFS predicts that marine 

mammals may be behaviorally harassed 

(i.e., Level B harassment) when exposed 

to underwater anthropogenic noise 

above received levels of 160 dB re 1 mPa 

(rms) for the impulsive sources (i.e., 

seismic airguns) evaluated here. 

Level A Harassment—NMFS’ 

Technical Guidance for Assessing the 

Effects of Anthropogenic Sound on 

Marine Mammal Hearing (Version 2.0) 

(Technical Guidance, 2018) identifies 

dual criteria to assess auditory injury 

(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 nonimpulsive). L–DEO’s proposed seismic 

survey includes the use of impulsive 

(seismic airguns) sources. 

These thresholds are provided in the 

table below. The references, analysis, 

and methodology used in the 

development of the thresholds are 

described in NMFS 2018 Technical 

Guidance, which may be accessed at 

www.fisheries.noaa.gov/national/ 

marine-mammal-protection/marinemammal-acoustic-technical-guidance. 

TABLE 3—THRESHOLDS IDENTIFYING THE ONSET OF PERMANENT THRESHOLD SHIFT

PTS onset acoustic thresholds * 

(received level) 

Hearing group Impulsive Non-impulsive 

Low-Frequency (LF) Cetaceans ...................................... Cell 1: Lpk,flat: 219 dB; L,E,LF,24h: 183 dB ........................ Cell 2: L,E,LF,24h: 199 dB. 

Mid-Frequency (MF) Cetaceans ...................................... Cell 3: Lpk,flat: 230 dB; L,E,MF,24h: 185 dB ....................... Cell 4: L,E,MF,24h: 198 dB. 

High-Frequency (HF) Cetaceans ..................................... Cell 5: Lpk,flat: 202 dB; L,E,HF,24h: 155 dB ....................... Cell 6: L,E,HF,24h: 173 dB. 

Phocid Pinnipeds (PW) (Underwater) ............................. Cell 7: Lpk,flat: 218 dB; L,E,PW,24h: 185 dB ...................... Cell 8: L,E,PW,24h: 201 dB. 

Otariid Pinnipeds (OW) (Underwater) ............................. Cell 9: Lpk,flat: 232 dB; L,E,OW,24h: 203 dB ...................... Cell 10: L,E,OW,24h: 219 dB. 

* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level thresholds associated with impulsive sounds, these thresholds should 

also be considered. 

Note: Peak sound pressure (Lpk) has a reference value of 1 μPa, and cumulative sound exposure level (LE) has a reference value of 1μPa2s. 

In this Table, thresholds are abbreviated to reflect American National Standards Institute standards (ANSI 2013). However, peak sound pressure 

is defined by ANSI 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 generalized hearing range. The subscript associated 

with cumulative sound exposure level thresholds indicates the designated marine mammal auditory weighting function (LF, MF, and HF 

cetaceans, and PW and OW pinnipeds) and that the recommended accumulation period is 24 hours. The cumulative sound exposure level 

thresholds 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 acoustic thresholds will be exceeded. 

Ensonified Area 

Here, we describe operational and 

environmental parameters of the activity 

and other relevant information that will 

feed into identifying the area ensonified 

above the acoustic thresholds. 

L–DEO’s modeling methodologies are 

described in greater detail in Appendix 

A of L–DEO’s IHA application. The 

proposed 2D survey would acquire data 

using the 36-airgun array with a total 

discharge volume of 6,600 in3 at a 

maximum tow depth of 12 m. L–DEO’s 

modeling approach uses ray tracing for 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30019 

the direct wave traveling from the array 

to the receiver and its associated source 

ghost (reflection at the air-water 

interface in the vicinity of the array), in 

a constant-velocity half-space (infinite 

homogeneous ocean layer, unbounded 

by a seafloor). To validate the model 

results, L–DEO measured propagation of 

pulses from the 36-airgun array at a tow 

depth of 6 m in the Gulf of Mexico, for 

deep water (∼1,600 m), intermediate 

water depth on the slope (∼600–1,100 

m), and shallow water (∼50 m) (Tolstoy 

et al., 2009; Diebold et al., 2010). 

L–DEO collected a MCS data set from 

R/V Langseth (array towed at 9 m depth) 

on an 8-km streamer in 2012 on the 

shelf of the Cascadia Margin off of 

Washington in water up to 200 m deep 

that allowed Crone et al. (2014) to 

analyze the hydrophone streamer data 

(>1,100 individual shots). These 

empirical data were then analyzed to 

determine in situ sound levels for 

shallow and upper intermediate water 

depths. These data suggest that modeled 

radii were 2–3 times larger than the 

measured radii in shallow water. 

Similarly, data collected by Crone et al. 

(2017) during a survey off New Jersey in 

2014 and 2015 confirmed that in situ 

measurements collected by the R/V 

Langseth hydrophone streamer were 2– 

3 times smaller than the predicted radii. 

L–DEO model results are used to 

determine the assumed radial distance 

to the 160-dB rms threshold for these 

arrays in deep water (>1,000 m) (down 

to a maximum water depth of 2,000 m). 

Water depths in the project area may be 

up to 2,800 m, but marine mammals in 

the region are generally not anticipated 

to dive below 2,000 m (e.g., Costa and 

Williams, 1999). L–DEO typically 

derives estimated distances for 

intermediate water depths by applying a 

correction factor of 1.5 to the model 

results for deep water. In this case, the 

estimated radial distance for 

intermediate (100–1,000 m) and shallow 

(<100 m) water depths is taken from 

Crone et al. (2014), as these empirical 

data were collected in the same region 

as this proposed survey. A correction 

factor of 1.15 was applied to account for 

differences in array tow depth. 

The estimated distances to the Level 

B harassment isopleths for the array are 

shown in Table 4. 

TABLE 4—PREDICTED RADIAL DISTANCES TO ISOPLETHS CORRESPONDING TO LEVEL B HARASSMENT THRESHOLD

Source and volume Tow depth 

(m) 

Water depth 

(m) 

Level B 

harassment 

zone 

(m) 

36 airgun array; 6,600 in3 ............................................................................................................ 12 >1000 1 6,733 

100–1000 2 9,468 

<100 2 12,650 

1 Distance based on L–DEO model results. 

2Based on empirical data from Crone et al. (2014) with scaling. 

Predicted distances to Level A 

harassment isopleths, which vary based 

on marine mammal hearing groups, 

were calculated based on modeling 

performed by L–DEO using the 

NUCLEUS source modeling software 

program and the NMFS User 

Spreadsheet, described below. The 

acoustic thresholds for impulsive 

sounds (e.g., airguns) contained in the 

Technical Guidance were presented as 

dual metric acoustic thresholds using 

both SELcum and peak sound pressure 

metrics (NMFS 2018). As dual metrics, 

NMFS considers onset of PTS (Level A 

harassment) to have occurred when 

either one of the two metrics is 

exceeded (i.e., metric resulting in the 

largest isopleth). The SELcum metric 

considers both level and duration of 

exposure, as well as auditory weighting 

functions by marine mammal hearing 

group. In recognition of the fact that the 

requirement to calculate Level A 

harassment ensonified areas could be 

more technically challenging to predict 

due to the duration component and the 

use of weighting functions in the new 

SELcum thresholds, NMFS developed an 

optional User Spreadsheet that includes 

tools to help predict a simple isopleth 

that can be used in conjunction with 

marine mammal density or occurrence 

to facilitate the estimation of take 

numbers. 

The values for SELcum and peak SPL 

for the Langseth airgun arrays were 

derived from calculating the modified 

far-field signature. The farfield signature 

is often used as a theoretical 

representation of the source level. To 

compute the farfield signature, the 

source level is estimated at a large 

distance below the array (e.g., 9 km), 

and this level is back projected 

mathematically to a notional distance of 

1 m from the array’s geometrical center. 

However, when the source is an array of 

multiple airguns separated in space, the 

source level from the theoretical farfield 

signature is not necessarily the best 

measurement of the source level that is 

physically achieved at the source 

(Tolstoy et al., 2009). Near the source (at 

short ranges, distances <1 km), the 

pulses of sound pressure from each 

individual airgun in the source array do 

not stack constructively, as they do for 

the theoretical farfield signature. The 

pulses from the different airguns spread 

out in time such that the source levels 

observed or modeled are the result of 

the summation of pulses from a few 

airguns, not the full array (Tolstoy et al., 

2009). At larger distances, away from 

the source array center, sound pressure 

of all the airguns in the array stack 

coherently, but not within one time 

sample, resulting in smaller source 

levels (a few dB) than the source level 

derived from the farfield signature. 

Because the farfield signature does not 

take into account the large array effect 

near the source and is calculated as a 

point source, the modified farfield 

signature is a more appropriate measure 

of the sound source level for distributed 

sound sources, such as airgun arrays. L– 

DEO used the acoustic modeling 

methodology as used for estimating 

Level B harassment distances with a 

small grid step of 1 m in both the inline 

and depth directions. The propagation 

modeling takes into account all airgun 

interactions at short distances from the 

source, including interactions between 

subarrays, which are modeled using the 

NUCLEUS software to estimate the 

notional signature and MATLAB 

software to calculate the pressure signal 

at each mesh point of a grid. 

In order to more realistically 

incorporate the Technical Guidance’s 

weighting functions over the seismic 

array’s full acoustic band, unweighted 

spectrum data for the Langseth’s airgun 

array (modeled in 1 Hz bands) was used 

to make adjustments (dB) to the 

unweighted spectrum levels, by 

frequency, according to the weighting 

functions for each relevant marine 

mammal hearing group. These adjusted/ 

weighted spectrum levels were then 

converted to pressures (mPa) in order to 

integrate them over the entire 

30020 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

broadband spectrum, resulting in 

broadband weighted source levels by 

hearing group that could be directly 

incorporated within the User 

Spreadsheet (i.e., to override the 

Spreadsheet’s more simple weighting 

factor adjustment). Using the User 

Spreadsheet’s ‘‘safe distance’’ 

methodology for mobile sources 

(described by Sivle et al., 2014) with the 

hearing group-specific weighted source 

levels, and inputs assuming spherical 

spreading propagation and information 

specific to the planned survey (i.e., the 

2.2 m/s source velocity and (worst-case) 

23-s shot interval), potential radial 

distances to auditory injury zones were 

then calculated for SELcum thresholds. 

Inputs to the User Spreadsheets in the 

form of estimated source levels are 

shown in Appendix A of L–DEO’s 

application. User Spreadsheets used by 

L–DEO to estimate distances to Level A 

harassment isopleths for the airgun 

arrays are also provided in Appendix A 

of the application. Outputs from the 

User Spreadsheets in the form of 

estimated distances to Level A 

harassment isopleths for the survey are 

shown in Table 5. As described above, 

NMFS considers onset of PTS (Level A 

harassment) to have occurred when 

either one of the dual metrics (SELcum

and Peak SPLflat) is exceeded (i.e., 

metric resulting in the largest isopleth). 

TABLE 5—MODELED RADIAL DISTANCES (m) TO ISOPLETHS CORRESPONDING TO LEVEL A HARASSMENT THRESHOLDS

Source 

(volume) Threshold 

Level A harassment zone 

(m) 

LF cetaceans MF cetaceans HF 

cetaceans Phocids Otariids 

36-airgun array (6,600 in3) ............................................. SELcum ...... 320 0 1 10 0 

Peak .......... 39 14 268 44 11 

Note that because of some of the 

assumptions included in the methods 

used (e.g., stationary receiver with no 

vertical or horizontal movement in 

response to the acoustic source), 

isopleths produced may be 

overestimates to some degree, which 

will ultimately result in some degree of 

overestimation of Level A harassment. 

However, these tools offer the best way 

to predict appropriate isopleths when 

more sophisticated modeling methods 

are not available, and NMFS continues 

to develop ways to quantitatively refine 

these tools and will qualitatively 

address the output where appropriate. 

For mobile sources, such as the 

proposed seismic survey, the User 

Spreadsheet predicts the closest 

distance at which a stationary animal 

would not incur PTS if the sound source 

traveled by the animal in a straight line 

at a constant speed. 

Auditory injury is unlikely to occur 

for mid-frequency cetaceans, otariid 

pinnipeds, and phocid pinnipeds given 

very small modeled zones of injury for 

those species (all estimated zones less 

than 15 m for mid-frequency cetaceans 

and otariid pinnipeds, up to a maximum 

of 44 m for phocid pinnipeds), in 

context of distributed source dynamics. 

The source level of the array is a 

theoretical definition assuming a point 

source and measurement in the far-field 

of the source (MacGillivray, 2006). As 

described by Caldwell and Dragoset 

(2000), an array is not a point source, 

but one that spans a small area. In the 

far-field, individual elements in arrays 

will effectively work as one source 

because individual pressure peaks will 

have coalesced into one relatively broad 

pulse. The array can then be considered 

a ‘‘point source.’’ For distances within 

the near-field, i.e., approximately 2–3 

times the array dimensions, pressure 

peaks from individual elements do not 

arrive simultaneously because the 

observation point is not equidistant 

from each element. The effect is 

destructive interference of the outputs 

of each element, so that peak pressures 

in the near-field will be significantly 

lower than the output of the largest 

individual element. Here, the relevant 

peak isopleth distances would in all 

cases be expected to be within the nearfield of the array where the definition of 

source level breaks down. Therefore, 

actual locations within this distance of 

the array center where the sound level 

exceeds the relevant peak SPL 

thresholds would not necessarily exist. 

In general, Caldwell and Dragoset (2000) 

suggest that the near-field for airgun 

arrays is considered to extend out to 

approximately 250 m. 

In order to provide quantitative 

support for this theoretical argument, 

we calculated expected maximum 

distances at which the near-field would 

transition to the far-field (Table 5). For 

a specific array one can estimate the 

distance at which the near-field 

transitions to the far-field by: 

with the condition that D >> l, and 

where D is the distance, L is the longest 

dimension of the array, and l is the 

wavelength of the signal (Lurton, 2002). 

Given that l can be defined by: 

where f is the frequency of the sound 

signal and v is the speed of the sound 

in the medium of interest, one can 

rewrite the equation for D as: 

and calculate D directly given a 

particular frequency and known speed 

of sound (here assumed to be 1,500 

meters per second in water, although 

this varies with environmental 

conditions). 

To determine the closest distance to 

the arrays at which the source level 

predictions in Table 5 are valid (i.e., 

maximum extent of the near-field), we 

calculated D based on an assumed 

frequency of 1 kHz. A frequency of 1 

kHz is commonly used in near-field/farfield calculations for airgun arrays 

(Zykov and Carr, 2014; MacGillivray, 

2006; NSF and USGS, 2011), and based 

on representative airgun spectrum data 

and field measurements of an airgun 

array used on the Langseth, nearly all 

(greater than 95 percent) of the energy 

from airgun arrays is below 1 kHz 

(Tolstoy et al., 2009). Thus, using 1 kHz 

as the upper cut-off for calculating the 

maximum extent of the near-field 

should reasonably represent the nearfield extent in field conditions. 

If the largest distance to the peak 

sound pressure level threshold was 

equal to or less than the longest 

dimension of the array (i.e., under the 

array), or within the near-field, then 

received levels that meet or exceed the 

threshold in most cases are not expected 

to occur. This is because within the 

near-field and within the dimensions of 

the array, the source levels specified in 

Appendix A of L–DEO’s application are 


EN04JN21.004</GPH> EN04JN21.005</GPH> EN04JN21.006</GPH>

Lz 

D=-

4;i, 

D - [Lz 

4v 
Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30021 

overestimated and not applicable. In 

fact, until one reaches a distance of 

approximately three or four times the 

near-field distance the average intensity 

of sound at any given distance from the 

array is still less than that based on 

calculations that assume a directional 

point source (Lurton, 2002). The 6,600- 

in3 airgun array planned for use during 

the proposed survey has an approximate 

diagonal of 28.8 m, resulting in a nearfield distance of 138.7 m at 1 kHz (NSF 

and USGS, 2011). Field measurements 

of this array indicate that the source 

behaves like multiple discrete sources, 

rather than a directional point source, 

beginning at approximately 400 m (deep 

site) to 1 km (shallow site) from the 

center of the array (Tolstoy et al., 2009), 

distances that are actually greater than 

four times the calculated 140-m nearfield distance. Within these distances, 

the recorded received levels were 

always lower than would be predicted 

based on calculations that assume a 

directional point source, and 

increasingly so as one moves closer 

towards the array (Tolstoy et al., 2009). 

Given this, relying on the calculated 

distance (138.7 m) as the distance at 

which we expect to be in the near-field 

is a conservative approach since even 

beyond this distance the acoustic 

modeling still overestimates the actual 

received level. Within the near-field, in 

order to explicitly evaluate the 

likelihood of exceeding any particular 

acoustic threshold, one would need to 

consider the exact position of the 

animal, its relationship to individual 

array elements, and how the individual 

acoustic sources propagate and their 

acoustic fields interact. Given that 

within the near-field and dimensions of 

the array source levels would be below 

those assumed here, we believe 

exceedance of the peak pressure 

threshold would only be possible under 

highly unlikely circumstances. 

In consideration of the received sound 

levels in the near-field as described 

above, we expect the potential for Level 

A harassment of mid-frequency 

cetaceans, otariid pinnipeds, and 

phocid pinnipeds to be de minimis, 

even before the likely moderating effects 

of aversion and/or other compensatory 

behaviors (e.g., Nachtigall et al., 2018) 

are considered. We do not believe that 

Level A harassment is a likely outcome 

for any mid-frequency cetacean, otariid 

pinniped, or phocid pinniped and do 

not propose to authorize any Level A 

harassment for these species. 

Marine Mammal Occurrence 

In this section we provide the 

information about the presence, density, 

and group dynamics of marine 

mammals that will inform the take 

calculations. The Navy’s Marine Species 

Density Database (DoN, 2019, 2021) is 

currently the most comprehensive 

compendium for density data available 

for the Gulf of Alaska (GOA) and is the 

only source of density data available for 

southeast Alaska. Habitat-based 

stratified marine mammal densities 

developed by the U.S. Navy for 

assessing potential impacts of training 

activities in the GOA (DoN, 2021; Rone 

et al., 2014, 2017) and at Behm Canal in 

southeast Alaska (DoN, 2019) represent 

the best available information for 

estimating potential marine mammal 

exposures. The Navy’s GOA Temporary 

Marine Activities Area (TMAA) is 

situated south of Prince William Sound 

and east of Kodiak Island. The northern 

boundary of the TMAA is 

approximately 24 nautical miles south 

of the Kenai Peninsula. Behm Canal is 

approximately 45 km east of Ketchikan, 

AK, inshore of the proposed survey area 

in the same general part of southeast 

Alaska. In general, GOA density values 

were used for offshore (deep water 

depths) portions of the survey area, and 

Behm Canal density values were used 

for inshore (shallow and intermediate 

water depths) portions. For some 

species, no Behm Canal density 

information is available, and the GOA 

density value was applied to all water 

depths. Density values are provided in 

Table 6 and discussed in greater detail 

below. 

TABLE 6—ESTIMATED DENSITY VALUES BY WATER DEPTH

[#/km2] 

Species Shallow depth 

(<100 m) 1

Intermediate 

depth 

(100–1,000 m) 1

Deep depth 

(>1,000 m) 1

Gray whale 4 ........................................................................................................................ 0.0486 0.0486 0 

Humpback whale ................................................................................................................. 3 0.0117 3 0.0117 4 0.0010 

Blue whale 4 ......................................................................................................................... 0.0001 0.0001 0.0005 

Fin whale ............................................................................................................................. 3 0.0001 3 0.0001 4 0.0160 

Sei whale 4 ........................................................................................................................... 0.0004 0.0004 0.0004 

Minke whale ......................................................................................................................... 3 0.0008 3 0.0008 4 0.0006 

Sperm whale 4 ...................................................................................................................... 0 0.0020 0.0013 

Baird’s beaked whale 4 ........................................................................................................ 0 0 0.0005 

Stejneger’s beaked whale 4 ................................................................................................. 0 0 0.0021 

Cuvier’s beaked whale 4 ...................................................................................................... 0 0 0.0020 

Pacific white-sided dolphin .................................................................................................. 3 0.0075 3 0.0075 4 0.0200 

Northern right whale dolphin 5 ............................................................................................. 0.0110 0.0276 0.0367 

Risso’s dolphin 2 .................................................................................................................. 0.0000 0.0000 0.0000 

Killer whale .......................................................................................................................... 3 0.0057 3 0.0057 4 0.0020 

Dall’s porpoise ..................................................................................................................... 3 0.1210 3 0.1210 4 0.0370 

Harbor porpoise 6 ................................................................................................................. 0.0330 0.0330 0 

Northern fur seal 4 ................................................................................................................ 0.0661 0.0661 0.0661 

California sea lion 3 .............................................................................................................. 0.0288 0.0288 0.0065 

Steller sea lion ..................................................................................................................... 3 0.3162 4 0.0570 0 

Northern elephant seal 4 ...................................................................................................... 0.0779 0.0779 0.0779 

Harbor seal .......................................................................................................................... 3 0.7811 4 0.1407 0 

1A zero value indicates the species is not expected to occur in that depth stratum. 

2 Nominal density value of 0.00001 applied to Risso’s dolphin. 

3Source: DoN, 2019; 4Source DoN, 2021; 5Source: Becker et al. (2016); 6 Hobbs and Waite (2010). 

30022 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

The Navy conducted comprehensive 

marine mammal surveys in theTMAA in 

2009 and 2013. Additional survey effort 

was conducted in 2015. These surveys 

used systematic line-transect survey 

protocols including visual and acoustic 

detection methods (Rone et al., 2010, 

2014, 2017). The data were collected in 

four strata that were designed to 

encompass the four distinct habitats 

within the TMAA and greater GOA: 

Inshore: All waters <1,000 m deep; 

Slope: From 1,000 m water depth to the 

Aleutian trench/subduction zone; 

Offshore: Waters offshore of the 

Aleutian trench/subduction zone; 

Seamount: Waters within defined 

seamount areas. Density values for the 

slope and seamount regions of the 

TMAA are not relevant for the survey 

area considered herein. There were 

insufficient sightings data from the 

2009, 2013, and 2015 line-transect 

surveys to calculate reliable density 

estimates for certain cetacean species in 

the GOA. In these cases, other available 

information supported development of 

density estimates. Additional sources of 

information include summer 2003 

cetacean surveys near the Kenai 

Peninsula, within Prince William Sound 

and around Kodiak Island (Waite, 2003 

in DoN, 2021), summer 2010–2012 linetransect data collected over a broad area 

north of 40° N, south of the Aleutian 

Islands, and between 170° E and 135° W 

during the International Whaling 

Commission-Pacific Ocean Whale and 

Ecosystem Research cruises (Hakamada 

et al., 2017), and analysis of acoustic 

data from the 2013 Navy-funded survey 

effort in the TMAA (Yack et al., 2015). 

See DoN (2021) for additional detail. 

When seasonal densities were available, 

the calculated exposures were based on 

summer densities, which are most 

representative of the proposed survey 

timing. 

Pinniped numbers are commonly 

assessed by counting individuals at 

haul-outs or the number of pups weaned 

at rookeries. Translating these numbers 

to in-water densities presents challenges 

unique to pinnipeds. No in-water line 

transect survey data were available for 

harbor seal, Steller sea lion, or 

California sea lion in the GOA. Surveys 

conducted by Rone et al. (2014) 

recorded sightings of northern elephant 

seal and northern fur seal in the TMAA; 

however, these data were insufficient to 

estimate a density for northern elephant 

seal, and were not used for northern fur 

seal due to the availability of more 

recent data. To account for the lack of 

in-water survey data for pinnipeds, 

published abundance estimates used in 

the density calculations were adjusted 

using a species-specific haul-out factor 

to estimate an in-water abundance for 

each species based on haul-out 

behavior. The calculated in-water 

abundance and an area of distribution 

specific to each species was used to 

estimate a density. See DoN (2021) for 

additional information. For pinnipeds, 

where monthly density estimates were 

available, the highest value from July or 

August was applied as most 

representative of the proposed survey 

timing. 

Due to a lack of sighting data specific 

to the Behm Canal area, the Navy 

derived density estimates based on data 

collected from various surveys 

(cetaceans) and shore counts 

(pinnipeds) conducted within southeast 

Alaska and GOA. Pinniped density 

estimates for the Behm Canal region 

were additionally derived from 

publications, NMFS SARs, and 

consultation with subject matter experts 

(DoN, 2019). Systematic ship surveys 

conducted in southeast Alaska waters 

from 1991 to 2012 provided data to 

develop stratified line-transect density 

estimates for harbor porpoise and Dall’s 

porpoise in regions overlapping a 

portion of the Behm Canal area 

(Dahlheim et al., 2015). Density 

information for the Behm Canal area is 

available for the following species: 

Minke whale, fin whale, humpback 

whale, Pacific white-sided dolphin, 

killer whale, harbor porpoise, Dall’s 

porpoise, and for all potentially affected 

pinniped species. 

The general approach for cetaceans of 

applying Behm Canal density estimates 

to survey effort in shallow and 

intermediate depth strata and GOA 

offshore density estimates to the deep 

depth stratum was applied for species 

for which appropriate estimates were 

available: Humpback whale, fin whale, 

minke whale, Pacific white-sided 

dolphin, killer whale, and Dall’s 

porpoise. Note that, for killer whales, 

Behm Canal densities are provided 

specific to transient and resident 

whales. We apply the higher transient 

killer whale density value to estimate 

killer whale exposures in shallow and 

intermediate water depths. Behm Canal 

pinniped densities would be expected 

to overestimate pinniped occurrence off 

the coast, and so were not used for 

intermediate-depth waters, but were 

applied to shallow waters where 

available. 

Certain species are not expected to 

occur in Behm Canal: Gray whale, blue 

whale, sei whale, sperm whale, beaked 

whales, northern fur seal, and northern 

elephant seal. For these species, we 

applied appropriate GOA density values 

to all depth strata (i.e., inshore GOA 

values to shallow and intermediate 

water depths and offshore GOA density 

values to deep water depths). Note that, 

while DoN (2021) provides an inshore 

density estimate for sperm whales, that 

stratum corresponds to water depths 

<1,000 m. We assume here that sperm 

whales do not occur in shallow water 

depths (<100 m). 

Gray whale densities are provided for 

two zones, nearshore (0–2.25 nmi from 

shore) and offshore (from 2.25–20 nmi 

from shore), based on density 

information in Carretta et al. (2000) and 

zones based on data from Shelden and 

Laake (2002). DoN (2021) assumes that 

gray whales do not occur in the region 

>20 nmi from shore. The nearshore 

density is used here to represent 

shallow and intermediate water (<1,000 

m deep). This approach assumes a 

higher density of gray whales across a 

larger area and is used as a 

precautionary approach. 

Harbor porpoise densities in DoN 

(2021) were derived from survey data 

collected in summer 1997 in southeast 

Alaska and 1998 in the Gulf of Alaska 

and included correction factors for both 

perception and availability bias (Hobbs 

and Waite, 2010). L–DEO proposed to 

use density information from Hobbs and 

Waite (2010) specific to southeast 

Alaska, which better represents the 

survey area than the GOA information 

presented for harbor porpoise in DoN 

(2021). Following DoN (2021), we 

assume harbor porpoise will not occur 

in deep water (>1,000 m). 

No regional density information is 

available for the northern right whale 

dolphin. Becker et al. (2016) used linetransect survey data collected between 

1991 and 2009 to develop predictive 

habitat-based models of cetacean 

densities in the California Current 

Ecosystem (the region from Baja 

California to southern British 

Columbia). The modeled density 

estimates were available on the scale of 

7 km by 10 km grid cells off California, 

Oregon, and Washington, and values 

were averaged for grid cells across 

Washington and Oregon corresponding 

with L–DEO’s shallow, intermediate, 

and deep water survey strata. These 

density values were applied to the 

portion of the survey area off Canada to 

calculate estimated exposures, as 

northern right whale dolphins do not 

typically occur beyond the California 

Current. The Risso’s dolphin is only 

rarely observed in or near the Navy’s 

GOA survey area, and does not occur in 

Behm Canal, so minimal densities were 

used to represent their potential 

presence (DoN, 2021). For California sea 

lion, density data is available in DoN 

(2021); however, it is likely that these 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30023 

values would underestimate presence of 

California sea lions in the proposed 

survey area. Therefore, information 

available in DoN (2019) for the Offshore 

Northwest Training and Testing 

(NWTT) Area (off Washington/Oregon) 

in the month of August was used; 

densities for 0–40 km from shore were 

applied to shallow and intermediate 

water depths, and the density for 0–450 

km from shore was used for deep water. 

The density for 40–70 km from shore 

was the lowest and was therefore not 

used. 

In British Columbia, several 

systematic surveys have been conducted 

in coastal waters (e.g., Williams and 

Thomas 2007; Ford et al., 2010; Best et 

al., 2015; Harvey et al., 2017). Surveys 

in coastal as well as offshore waters 

were conducted by Fisheries and 

Oceans Canada (DFO) during 2002 to 

2008. However, density estimates for the 

survey areas outside the U.S. EEZ, i.e., 

in the Canadian EEZ, were not readily 

available, so density estimates for U.S. 

waters were applied to the entire survey 

area. 

Take Calculation and Estimation 

Here we describe how the information 

provided above is brought together to 

produce a quantitative take estimate. In 

order to estimate the number of marine 

mammals predicted to be exposed to 

sound levels that would result in Level 

A or Level B harassment, radial 

distances from the airgun array to 

predicted isopleths corresponding to the 

Level A harassment and Level B 

harassment thresholds are calculated, as 

described above. Those radial distances 

are then used to calculate the area(s) 

around the airgun array predicted to be 

ensonified to sound levels that exceed 

the Level A and Level B harassment 

thresholds. The distance for the 160-dB 

threshold (based on L–DEO model 

results) was used to draw a buffer 

around every transect line in GIS to 

determine the total ensonified area in 

each depth category. Estimated 

incidents of exposure above Level A and 

Level B harassment criteria are 

presented in Table 7. For additional 

details regarding calculations of 

ensonified area, please see Appendix D 

of L–DEO’s application. As noted 

previously, L–DEO has added 25 

percent in the form of operational days, 

which is equivalent to adding 25 

percent to the proposed line-kms to be 

surveyed. This accounts for the 

possibility that additional operational 

days are required, but likely results in 

an overestimate of actual exposures. 

As previously noted, NMFS cannot 

authorize incidental take under the 

MMPA that may occur within the 

territorial seas of foreign nations (from 

0–12 nmi (22.2 km) from shore), as the 

MMPA does not apply in those waters. 

However, NMFS has still calculated the 

estimated level of incidental take in the 

entire activity area (including Canadian 

territorial waters) as part of the analysis 

supporting our determination under the 

MMPA that the activity will have a 

negligible impact on the affected 

species. The total estimated take in U.S. 

and Canadian waters is presented in 

Table 8 (see Negligible Impact Analysis 

and Determination). 

The estimated marine mammal 

exposures above harassment thresholds 

are generally assumed here to equate to 

take, and the estimates form the basis 

for our proposed take authorization 

numbers. For the species for which 

NMFS does not expect there to be a 

reasonable potential for take by Level A 

harassment to occur, i.e., mid-frequency 

cetaceans and all pinnipeds, the 

estimated exposures above Level A 

harassment thresholds have been added 

to the estimated exposures above the 

Level B harassment threshold to 

produce a total number of incidents of 

take by Level B harassment that is 

proposed for authorization. Estimated 

exposures and proposed take numbers 

for authorization are shown in Table 7. 

Regarding humpback whale take 

numbers, we assume that whales 

encountered will follow Wade (2017), 

i.e., that 96.1 percent of takes would 

accrue to the Hawaii DPS and 3.8 

percent to the Mexico DPS. Of the 

estimated take of gray whales, and based 

on guidance provided through 

interagency consultation under section 

7 of the ESA, we assume that 0.1 

percent of encountered whales would be 

from the WNP stock and propose to 

authorize take accordingly. For Steller 

sea lions, 2.2 percent are assumed to 

belong to the western DPS (Hastings et 

al., 2020). 

TABLE 7—ESTIMATED TAKING BY LEVEL A AND LEVEL B HARASSMENT, AND PERCENTAGE OF POPULATION

Species Stock 1

Estimated 

Level B 

harassment 

Estimated 

Level A 

harassment 

Proposed 

Level B 

harassment 

Proposed 

Level A 

harassment 

Total take Percent of 

stock 1

Gray whale ........................................ WNP ..................................................

ENP ...................................................

1,450 45 2 

1,448 

0 

45 

2 

1,493 

0.7 

5.5 

Humpback whale ............................... ............................................................ 403 14 403 14 417 4.1 

Blue whale ......................................... ............................................................ 31 1 31 1 32 2.1

Fin whale 2 ......................................... ............................................................ 873 44 873 44 917 n/a 

Sei whale ........................................... ............................................................ 34 1 34 1 35 6.7 

Minke whale 2 .................................... ............................................................ 57 2 57 2 59 n/a 

Sperm whale 2 ................................... ............................................................ 131 0 131 0 131 n/a 

Baird’s beaked whale 2 ...................... ............................................................ 29 0 29 0 29 n/a 

Stejneger’s beaked whale 2 ............... ............................................................ 120 0 120 0 120 n/a 

Cuvier’s beaked whale 2 .................... ............................................................ 114 0 114 0 114 n/a 

Pacific white-sided dolphin ................ ............................................................ 1,371 3 1,374 0 1,374 5.1 

Northern right whale dolphin ............. ............................................................ 922 5 927 0 927 3.5 

Risso’s dolphin 3 ................................ ............................................................ 1 0 22 0 22 0.3 

Killer whale ........................................ Offshore ............................................. 290 0 290 0 290 96.7 

GOA/BSAI Transient ......................... 49.4 

WC Transient .................................... 83.1 

AK Resident ...................................... 12.4 

Northern Resident ............................. 96.0 

Dall’s porpoise ................................... ............................................................ 5,661 178 5,661 178 5,839 7.0 

Harbor porpoise ................................ ............................................................ 990 26 990 26 1,016 n/a 

Northern fur seal ............................... ............................................................ 5,804 8 5,812 0 5,812 1.0 

California sea lion ............................. ............................................................ 1,256 1 1,258 0 1,258 0.5 

Steller sea lion .................................. WDPS ................................................

EDPS .................................................

2,433 2 54 

2,381 

0 

0 

54 

2,381 

0.1 

5.5 

Northern elephant seal ...................... ............................................................ 6,811 39 6,850 0 6,850 3.8 

Harbor seal ........................................ Sitka/Chatham Strait ......................... 5,992 21 6,012 0 6,012 45.2 

Dixon/Cape Decision ......................... 25.6 

30024 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

TABLE 7—ESTIMATED TAKING BY LEVEL A AND LEVEL B HARASSMENT, AND PERCENTAGE OF POPULATION—Continued 

Species Stock 1

Estimated 

Level B 

harassment 

Estimated 

Level A 

harassment 

Proposed 

Level B 

harassment 

Proposed 

Level A 

harassment 

Total take Percent of 

stock 1

Clarence Strait .................................. 21.7 

1 In most cases, where multiple stocks are being affected, for the purposes of calculating the percentage of the stock impacted, the take is being analyzed as if all 

proposed takes occurred within each stock. Where necessary, additional discussion is provided in the Small Numbers section. 2As noted in Table 1, there is no estimate of abundance available for these species. 

3Estimated exposure of one Risso’s dolphin increased to group size of 22 (Barlow, 2016). 

Proposed Mitigation 

In order to issue an IHA under 

Section 101(a)(5)(D) of the MMPA, 

NMFS must set forth the permissible 

methods of taking pursuant to the 

activity, and other means of effecting 

the least practicable impact on the 

species or stock and its habitat, paying 

particular attention to rookeries, mating 

grounds, and areas of similar 

significance, and on the availability of 

the species or stock for taking for certain 

subsistence uses (latter not applicable 

for this action). NMFS regulations 

require applicants for incidental take 

authorizations to include information 

about the availability and feasibility 

(economic and technological) of 

equipment, methods, and manner of 

conducting the activity or other means 

of effecting the least practicable adverse 

impact upon the affected species or 

stocks and their habitat (50 CFR 

216.104(a)(11)). 

In evaluating how mitigation may or 

may not be appropriate to ensure the 

least practicable adverse impact on 

species or stocks and their habitat, as 

well as subsistence uses where 

applicable, we carefully consider two 

primary factors: 

(1) The manner in which, and the 

degree to which, the successful 

implementation of the measure(s) is 

expected to reduce impacts to marine 

mammals, marine mammal species or 

stocks, and their habitat. This considers 

the nature of the potential adverse 

impact being mitigated (likelihood, 

scope, range). It further considers the 

likelihood that the measure will be 

effective if implemented (probability of 

accomplishing the mitigating result if 

implemented as planned), the 

likelihood of effective implementation 

(probability implemented as planned); 

and 

(2) The practicability of the measures 

for applicant implementation, which 

may consider such things as cost, 

impact on operations, and, in the case 

of a military readiness activity, 

personnel safety, practicality of 

implementation, and impact on the 

effectiveness of the military readiness 

activity. 

In order to satisfy the MMPA’s least 

practicable adverse impact standard, 

NMFS has evaluated a suite of basic 

mitigation protocols for seismic surveys 

that are required regardless of the status 

of a stock. Additional or enhanced 

protections may be required for species 

whose stocks are in particularly poor 

health and/or are subject to some 

significant additional stressor that 

lessens that stock’s ability to weather 

the effects of the specified activities 

without worsening its status. We 

reviewed seismic mitigation protocols 

required or recommended elsewhere 

(e.g., HESS, 1999; DOC, 2013; IBAMA, 

2018; Kyhn et al., 2011; JNCC, 2017; 

DEWHA, 2008; BOEM, 2016; DFO, 

2008; GHFS, 2015; MMOA, 2016; 

Nowacek et al., 2013; Nowacek and 

Southall, 2016), recommendations 

received during public comment 

periods for previous actions, and the 

available scientific literature. We also 

considered recommendations given in a 

number of review articles (e.g., Weir and 

Dolman, 2007; Compton et al., 2008; 

Parsons et al., 2009; Wright and 

Cosentino, 2015; Stone, 2015b). This 

exhaustive review and consideration of 

public comments regarding previous, 

similar activities has led to development 

of the protocols included here. 

Vessel-Based Visual Mitigation 

Monitoring 

Visual monitoring requires the use of 

trained observers (herein referred to as 

visual protected species observers 

(PSOs)) to scan the ocean surface for the 

presence of marine mammals. The area 

to be scanned visually includes 

primarily the exclusion zone (EZ), 

within which observation of certain 

marine mammals requires shutdown of 

the acoustic source, but also a buffer 

zone and, to the extent possible 

depending on conditions, the 

surrounding waters. The buffer zone 

means an area beyond the EZ to be 

monitored for the presence of marine 

mammals that may enter the EZ. During 

pre-start clearance monitoring (i.e., 

before ramp-up begins), the buffer zone 

also acts as an extension of the EZ in 

that observations of marine mammals 

within the buffer zone would also 

prevent airgun operations from 

beginning (i.e., ramp-up). The buffer 

zone encompasses the area at and below 

the sea surface from the edge of the 0– 

500 m EZ, out to a radius of 1,000 m 

from the edges of the airgun array (500– 

1,000 m). This 1,000-m zone (EZ plus 

buffer) represents the pre-start clearance 

zone. Visual monitoring of the EZ and 

adjacent waters is intended to establish 

and, when visual conditions allow, 

maintain zones around the sound source 

that are clear of marine mammals, 

thereby reducing or eliminating the 

potential for injury and minimizing the 

potential for more severe behavioral 

reactions for animals occurring closer to 

the vessel. Visual monitoring of the 

buffer zone is intended to (1) provide 

additional protection to naı ̈ve marine 

mammals that may be in the area during 

pre-start clearance, and (2) during 

airgun use, aid in establishing and 

maintaining the EZ by alerting the 

visual observer and crew of marine 

mammals that are outside of, but may 

approach and enter, the EZ. 

L–DEO must use dedicated, trained, 

NMFS-approved PSOs. The PSOs must 

have no tasks other than to conduct 

observational effort, record 

observational data, and communicate 

with and instruct relevant vessel crew 

with regard to the presence of marine 

mammals and mitigation requirements. 

PSO resumes shall be provided to 

NMFS for approval. 

At least one of the visual and two of 

the acoustic PSOs (discussed below) 

aboard the vessel must have a minimum 

of 90 days at-sea experience working in 

those roles, respectively, with no more 

than 18 months elapsed since the 

conclusion of the at-sea experience. One 

visual PSO with such experience shall 

be designated as the lead for the entire 

protected species observation team. The 

lead PSO shall serve as primary point of 

contact for the vessel operator and 

ensure all PSO requirements per the 

IHA are met. To the maximum extent 

practicable, the experienced PSOs 

should be scheduled to be on duty with 

those PSOs with appropriate training 

but who have not yet gained relevant 

experience. 

During survey operations (e.g., any 

day on which use of the acoustic source 

is planned to occur, and whenever the 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30025 

acoustic source is in the water, whether 

activated or not), a minimum of two 

visual PSOs must be on duty and 

conducting visual observations at all 

times during daylight hours (i.e., from 

30 minutes prior to sunrise through 30 

minutes following sunset). Visual 

monitoring of the pre-start clearance 

zone must begin no less than 30 minutes 

prior to ramp-up, and monitoring must 

continue until one hour after use of the 

acoustic source ceases or until 30 

minutes past sunset. Visual PSOs shall 

coordinate to ensure 360° visual 

coverage around the vessel from the 

most appropriate observation posts, and 

shall conduct visual observations using 

binoculars and the naked eye while free 

from distractions and in a consistent, 

systematic, and diligent manner. 

PSOs shall establish and monitor the 

exclusion and buffer zones. These zones 

shall be based upon the radial distance 

from the edges of the acoustic source 

(rather than being based on the center of 

the array or around the vessel itself). 

During use of the acoustic source (i.e., 

anytime airguns are active, including 

ramp-up), detections of marine 

mammals within the buffer zone (but 

outside the EZ) shall be communicated 

to the operator to prepare for the 

potential shutdown of the acoustic 

source. Visual PSOs will immediately 

communicate all observations to the on 

duty acoustic PSO(s), including any 

determination by the PSO regarding 

species identification, distance, and 

bearing and the degree of confidence in 

the determination. Any observations of 

marine mammals by crew members 

shall be relayed to the PSO team. During 

good conditions (e.g., daylight hours; 

Beaufort sea state (BSS) 3 or less), visual 

PSOs shall conduct observations when 

the acoustic source is not operating for 

comparison of sighting rates and 

behavior with and without use of the 

acoustic source and between acquisition 

periods, to the maximum extent 

practicable. 

Visual PSOs may be on watch for a 

maximum of 4 consecutive hours 

followed by a break of at least one hour 

between watches and may conduct a 

maximum of 12 hours of observation per 

24-hour period. Combined observational 

duties (visual and acoustic but not at 

same time) may not exceed 12 hours per 

24-hour period for any individual PSO. 

Passive Acoustic Monitoring 

Acoustic monitoring means the use of 

trained personnel (sometimes referred to 

as passive acoustic monitoring (PAM) 

operators, herein referred to as acoustic 

PSOs) to operate PAM equipment to 

acoustically detect the presence of 

marine mammals. Acoustic monitoring 

involves acoustically detecting marine 

mammals regardless of distance from 

the source, as localization of animals 

may not always be possible. Acoustic 

monitoring is intended to further 

support visual monitoring (during 

daylight hours) in maintaining an EZ 

around the sound source that is clear of 

marine mammals. In cases where visual 

monitoring is not effective (e.g., due to 

weather, nighttime), acoustic 

monitoring may be used to allow certain 

activities to occur, as further detailed 

below. 

PAM would take place in addition to 

the visual monitoring program. Visual 

monitoring typically is not effective 

during periods of poor visibility or at 

night, and even with good visibility, is 

unable to detect marine mammals when 

they are below the surface or beyond 

visual range. Acoustic monitoring can 

be used in addition to visual 

observations to improve detection, 

identification, and localization of 

cetaceans. The acoustic monitoring 

would serve to alert visual PSOs (if on 

duty) when vocalizing cetaceans are 

detected. It is only useful when marine 

mammals vocalize, but it can be 

effective either by day or by night, and 

does not depend on good visibility. It 

would be monitored in real time so that 

the visual observers can be advised 

when cetaceans are detected. 

The R/V Langseth will use a towed 

PAM system, which must be monitored 

by at a minimum one on duty acoustic 

PSO beginning at least 30 minutes prior 

to ramp-up and at all times during use 

of the acoustic source. Acoustic PSOs 

may be on watch for a maximum of 4 

consecutive hours followed by a break 

of at least one hour between watches 

and may conduct a maximum of 12 

hours of observation per 24-hour period. 

Combined observational duties (acoustic 

and visual but not at same time) may 

not exceed 12 hours per 24-hour period 

for any individual PSO. 

Survey activity may continue for 30 

minutes when the PAM system 

malfunctions or is damaged, while the 

PAM operator diagnoses the issue. If the 

diagnosis indicates that the PAM system 

must be repaired to solve the problem, 

operations may continue for an 

additional 5 hours without acoustic 

monitoring during daylight hours only 

under the following conditions: 

• Sea state is less than or equal to 

BSS 4; 

• No marine mammals (excluding 

delphinids) detected solely by PAM in 

the applicable EZ in the previous 2 

hours; 

• NMFS is notified via email as soon 

as practicable with the time and 

location in which operations began 

occurring without an active PAM 

system; and 

• Operations with an active acoustic 

source, but without an operating PAM 

system, do not exceed a cumulative total 

of 5 hours in any 24-hour period. 

Establishment of Exclusion and PreStart Clearance Zones 

An EZ is a defined area within which 

occurrence of a marine mammal triggers 

mitigation action intended to reduce the 

potential for certain outcomes, e.g., 

auditory injury, disruption of critical 

behaviors. The PSOs would establish a 

minimum EZ with a 500-m radius. The 

500-m EZ would be based on radial 

distance from the edge of the airgun 

array (rather than being based on the 

center of the array or around the vessel 

itself). With certain exceptions 

(described below), if a marine mammal 

appears within or enters this zone, the 

acoustic source would be shut down. 

The pre-start clearance zone is 

defined as the area that must be clear of 

marine mammals prior to beginning 

ramp-up of the acoustic source, and 

includes the EZ plus the buffer zone. 

Detections of marine mammals within 

the pre-start clearance zone would 

prevent airgun operations from 

beginning (i.e., ramp-up). 

The 500-m EZ is intended to be 

precautionary in the sense that it would 

be expected to contain sound exceeding 

the injury criteria for all cetacean 

hearing groups, (based on the dual 

criteria of SELcum and peak SPL), while 

also providing a consistent, reasonably 

observable zone within which PSOs 

would typically be able to conduct 

effective observational effort. 

Additionally, a 500-m EZ is expected to 

minimize the likelihood that marine 

mammals will be exposed to levels 

likely to result in more severe 

behavioral responses. Although 

significantly greater distances may be 

observed from an elevated platform 

under good conditions, we believe that 

500 m is likely regularly attainable for 

PSOs using the naked eye during typical 

conditions. The pre-start clearance zone 

simply represents the addition of a 

buffer to the EZ, doubling the EZ size 

during pre-clearance. 

An extended EZ of 1,500 m must be 

enforced for all beaked whales. No 

buffer of this extended EZ is required. 

Pre-Start Clearance and Ramp-Up 

Ramp-up (sometimes referred to as 

‘‘soft start’’) means the gradual and 

systematic increase of emitted sound 

levels from an airgun array. Ramp-up 

begins by first activating a single airgun 

of the smallest volume, followed by 

doubling the number of active elements 

30026 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

in stages until the full complement of an 

array’s airguns are active. Each stage 

should be approximately the same 

duration, and the total duration should 

not be less than approximately 20 

minutes. The intent of pre-start 

clearance observation (30 minutes) is to 

ensure no protected species are 

observed within the pre-clearance zone 

(or extended EZ, for beaked whales) 

prior to the beginning of ramp-up. 

During pre-start clearance period is the 

only time observations of marine 

mammals in the buffer zone would 

prevent operations (i.e., the beginning of 

ramp-up). The intent of ramp-up is to 

warn marine mammals of pending 

seismic operations and to allow 

sufficient time for those animals to leave 

the immediate vicinity. A ramp-up 

procedure, involving a step-wise 

increase in the number of airguns firing 

and total array volume until all 

operational airguns are activated and 

the full volume is achieved, is required 

at all times as part of the activation of 

the acoustic source. All operators must 

adhere to the following pre-start 

clearance and ramp-up requirements: 

• The operator must notify a 

designated PSO of the planned start of 

ramp-up as agreed upon with the lead 

PSO; the notification time should not be 

less than 60 minutes prior to the 

planned ramp-up in order to allow the 

PSOs time to monitor the pre-start 

clearance zone (and extended EZ) for 30 

minutes prior to the initiation of rampup (pre-start clearance); 

• Ramp-ups shall be scheduled so as 

to minimize the time spent with the 

source activated prior to reaching the 

designated run-in; 

• One of the PSOs conducting prestart clearance observations must be 

notified again immediately prior to 

initiating ramp-up procedures and the 

operator must receive confirmation from 

the PSO to proceed; 

• Ramp-up may not be initiated if any 

marine mammal is within the applicable 

exclusion or buffer zone. If a marine 

mammal is observed within the pre-start 

clearance zone (or extended EZ, for 

beaked whales) during the 30 minute 

pre-start clearance period, ramp-up may 

not begin until the animal(s) has been 

observed exiting the zones or until an 

additional time period has elapsed with 

no further sightings (15 minutes for 

small odontocetes and pinnipeds, and 

30 minutes for all mysticetes and all 

other odontocetes, including sperm 

whales, beaked whales, and large 

delphinids, such as killer whales); 

• Ramp-up shall begin by activating a 

single airgun of the smallest volume in 

the array and shall continue in stages by 

doubling the number of active elements 

at the commencement of each stage, 

with each stage of approximately the 

same duration. Duration shall not be 

less than 20 minutes. The operator must 

provide information to the PSO 

documenting that appropriate 

procedures were followed; 

• PSOs must monitor the pre-start 

clearance zone (and extended EZ) 

during ramp-up, and ramp-up must 

cease and the source must be shut down 

upon detection of a marine mammal 

within the applicable zone. Once rampup has begun, detections of marine 

mammals within the buffer zone do not 

require shutdown, but such observation 

shall be communicated to the operator 

to prepare for the potential shutdown; 

• Ramp-up may occur at times of 

poor visibility, including nighttime, if 

appropriate acoustic monitoring has 

occurred with no detections in the 30 

minutes prior to beginning ramp-up. 

Acoustic source activation may only 

occur at times of poor visibility where 

operational planning cannot reasonably 

avoid such circumstances; 

• If the acoustic source is shut down 

for brief periods (i.e., less than 30 

minutes) for reasons other than that 

described for shutdown (e.g., 

mechanical difficulty), it may be 

activated again without ramp-up if PSOs 

have maintained constant visual and/or 

acoustic observation and no visual or 

acoustic detections of marine mammals 

have occurred within the applicable EZ. 

For any longer shutdown, pre-start 

clearance observation and ramp-up are 

required. For any shutdown at night or 

in periods of poor visibility (e.g., BSS 4 

or greater), ramp-up is required, but if 

the shutdown period was brief and 

constant observation was maintained, 

pre-start clearance watch of 30 minutes 

is not required; and 

• Testing of the acoustic source 

involving all elements requires rampup. Testing limited to individual source 

elements or strings does not require 

ramp-up but does require pre-start 

clearance of 30 min. 

Shutdown 

The shutdown of an airgun array 

requires the immediate de-activation of 

all individual airgun elements of the 

array. Any PSO on duty will have the 

authority to delay the start of survey 

operations or to call for shutdown of the 

acoustic source if a marine mammal is 

detected within the applicable EZ. The 

operator must also establish and 

maintain clear lines of communication 

directly between PSOs on duty and 

crew controlling the acoustic source to 

ensure that shutdown commands are 

conveyed swiftly while allowing PSOs 

to maintain watch. When both visual 

and acoustic PSOs are on duty, all 

detections will be immediately 

communicated to the remainder of the 

on-duty PSO team for potential 

verification of visual observations by the 

acoustic PSO or of acoustic detections 

by visual PSOs. When the airgun array 

is active (i.e., anytime one or more 

airguns is active, including during 

ramp-up) and (1) a marine mammal 

appears within or enters the applicable 

EZ and/or (2) a marine mammal (other 

than delphinids, see below) is detected 

acoustically and localized within the 

applicable EZ, the acoustic source will 

be shut down. When shutdown is called 

for by a PSO, the acoustic source will 

be immediately deactivated and any 

dispute resolved only following 

deactivation. Additionally, shutdown 

will occur whenever PAM alone 

(without visual sighting), confirms 

presence of marine mammal(s) in the 

EZ. If the acoustic PSO cannot confirm 

presence within the EZ, visual PSOs 

will be notified but shutdown is not 

required. 

Following a shutdown, airgun activity 

would not resume until the marine 

mammal has cleared the EZ. The animal 

would be considered to have cleared the 

EZ if it is visually observed to have 

departed the EZ (i.e., animal is not 

required to fully exit the buffer zone 

where applicable), or it has not been 

seen within the EZ for 15 minutes for 

small odontocetes and pinnipeds, or 30 

minutes for all mysticetes and all other 

odontocetes, including sperm whales, 

beaked whales, and large delphinids, 

such as killer whales. 

The shutdown requirement can be 

waived for small dolphins if an 

individual is detected within the EZ. As 

defined here, the small dolphin group is 

intended to encompass those members 

of the Family Delphinidae most likely to 

voluntarily approach the source vessel 

for purposes of interacting with the 

vessel and/or airgun array (e.g., bow 

riding). This exception to the shutdown 

requirement applies solely to specific 

genera of small dolphins 

(Lagenorhynchus and Lissodelphis). 

We include this small dolphin 

exception because shutdown 

requirements for small dolphins under 

all circumstances represent 

practicability concerns without likely 

commensurate benefits for the animals 

in question. Small dolphins are 

generally the most commonly observed 

marine mammals in the specific 

geographic region and would typically 

be the only marine mammals likely to 

intentionally approach the vessel. As 

described above, auditory injury is 

extremely unlikely to occur for midfrequency cetaceans (e.g., delphinids), 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30027 

as this group is relatively insensitive to 

sound produced at the predominant 

frequencies in an airgun pulse while 

also having a relatively high threshold 

for the onset of auditory injury (i.e., 

permanent threshold shift). 

A large body of anecdotal evidence 

indicates that small dolphins commonly 

approach vessels and/or towed arrays 

during active sound production for 

purposes of bow riding, with no 

apparent effect observed in those 

delphinoids (e.g., Barkaszi et al., 2012, 

2018). The potential for increased 

shutdowns resulting from such a 

measure would require the Langseth to 

revisit the missed track line to reacquire 

data, resulting in an overall increase in 

the total sound energy input to the 

marine environment and an increase in 

the total duration over which the survey 

is active in a given area. Although other 

mid-frequency hearing specialists (e.g., 

large delphinids) are no more likely to 

incur auditory injury than are small 

dolphins, they are much less likely to 

approach vessels. Therefore, retaining a 

shutdown requirement for large 

delphinids would not have similar 

impacts in terms of either practicability 

for the applicant or corollary increase in 

sound energy output and time on the 

water. We do anticipate some benefit for 

a shutdown requirement for large 

delphinids in that it simplifies 

somewhat the total range of decisionmaking for PSOs and may preclude any 

potential for physiological effects other 

than to the auditory system as well as 

some more severe behavioral reactions 

for any such animals in close proximity 

to the source vessel. 

Visual PSOs shall use best 

professional judgment in making the 

decision to call for a shutdown if there 

is uncertainty regarding identification 

(i.e., whether the observed marine 

mammal(s) belongs to one of the 

delphinid genera for which shutdown is 

waived or one of the species with a 

larger EZ). 

L–DEO must implement shutdown if 

a marine mammal species for which 

take was not authorized, or a species for 

which authorization was granted but the 

takes have been met, approaches the 

Level A or Level B harassment zones. L– 

DEO must also implement shutdown if 

any of the following are observed at any 

distance: 

• Any large whale (defined as a 

sperm whale or any mysticete species) 

with a calf (defined as an animal less 

than two-thirds the body size of an adult 

observed to be in close association with 

an adult); 

• An aggregation of six or more large 

whales; and/or 

• A North Pacific right whale. 

Vessel Strike Avoidance 

1. Vessel operators and crews must 

maintain a vigilant watch for all 

protected species and slow down, stop 

their vessel, or alter course, as 

appropriate and regardless of vessel 

size, to avoid striking any marine 

mammal. A visual observer aboard the 

vessel must monitor a vessel strike 

avoidance zone around the vessel 

(distances stated below). Visual 

observers monitoring the vessel strike 

avoidance zone may be third-party 

observers (i.e., PSOs) or crew members, 

but crew members responsible for these 

duties must be provided sufficient 

training to 1) distinguish marine 

mammals from other phenomena and 2) 

broadly to identify a marine mammal as 

a right whale, other whale (defined in 

this context as sperm whales or baleen 

whales other than right whales), or other 

marine mammal. 

2. Vessel speeds must also be reduced 

to 10 kn or less when mother/calf pairs, 

pods, or large assemblages of cetaceans 

are observed near a vessel. 

3. All vessels must maintain a 

minimum separation distance of 500 m 

from right whales. If a whale is observed 

but cannot be confirmed as a species 

other than a right whale, the vessel 

operator must assume that it is a right 

whale and take appropriate action. 

4. All vessels must maintain a 

minimum separation distance of 100 m 

from sperm whales and all other baleen 

whales. 

5. All vessels must, to the maximum 

extent practicable, attempt to maintain a 

minimum separation distance of 50 m 

from all other marine mammals, with an 

understanding that at times this may not 

be possible (e.g., for animals that 

approach the vessel). 

6. When marine mammals are sighted 

while a vessel is underway, the vessel 

shall take action as necessary to avoid 

violating the relevant separation 

distance (e.g., attempt to remain parallel 

to the animal’s course, avoid excessive 

speed or abrupt changes in direction 

until the animal has left the area). If 

marine mammals are sighted within the 

relevant separation distance, the vessel 

must reduce speed and shift the engine 

to neutral, not engaging the engines 

until animals are clear of the area. This 

does not apply to any vessel towing gear 

or any vessel that is navigationally 

constrained. 

7. These requirements do not apply in 

any case where compliance would 

create an imminent and serious threat to 

a person or vessel or to the extent that 

a vessel is restricted in its ability to 

maneuver and, because of the 

restriction, cannot comply. 

We have carefully evaluated the suite 

of mitigation measures described here 

and considered a range of other 

measures in the context of ensuring that 

we prescribe the means of effecting the 

least practicable adverse impact on the 

affected marine mammal species and 

stocks and their habitat. Based on our 

evaluation of the proposed measures, as 

well as other measures considered by 

NMFS described above, NMFS has 

preliminarily determined that the 

mitigation measures provide the means 

of effecting the least practicable impact 

on the affected species or stocks and 

their habitat, paying particular attention 

to rookeries, mating grounds, and areas 

of similar significance. 

Mitigation Measures in Canadian 

Waters 

As stated previously, NMFS cannot 

authorize the incidental take of marine 

mammals in the territorial seas of 

foreign nations, as the MMPA does not 

apply in those waters. L–DEO is 

required to adhere to the mitigation 

measures described above while 

operating within the U.S. EEZ and 

Canadian EEZ. The requirements do not 

apply within Canadian territorial 

waters. NMFS expects that DFO may 

prescribe mitigation measures that 

would apply to L–DEO’s survey 

operations within the Canadian EEZ and 

Canadian territorial waters but is 

currently unaware of the specifics of 

any potential measures. While operating 

within the Canadian EEZ but outside 

Canadian territorial waters, if mitigation 

requirements prescribed by NMFS differ 

from the requirements established under 

Canadian law, L–DEO would adhere to 

the most protective measure. For 

operations in Canadian territorial 

waters, L–DEO would implement 

measures required under Canadian law 

(if any). If information regarding 

measures required under Canadian law 

becomes available prior to NMFS’ final 

decision on this request for IHA, NMFS 

will consider it as appropriate in 

making its negligible impact 

determination. 

Proposed Monitoring and Reporting 

In order to issue an IHA for an 

activity, Section 101(a)(5)(D) of the 

MMPA states that 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 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 

30028 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

mammals that are expected to be 

present in the proposed action area. 

Effective reporting is critical both to 

compliance as well as ensuring that the 

most value is obtained from the required 

monitoring. 

Monitoring and reporting 

requirements prescribed by NMFS 

should contribute to improved 

understanding of one or more of the 

following: 

• Occurrence of marine mammal 

species or stocks in the area in which 

take is anticipated (e.g., presence, 

abundance, distribution, density); 

• Nature, scope, or context of likely 

marine mammal exposure to potential 

stressors/impacts (individual or 

cumulative, acute or chronic), through 

better understanding of: (1) Action or 

environment (e.g., source 

characterization, propagation, ambient 

noise); (2) affected species (e.g., life 

history, dive patterns); (3) co-occurrence 

of marine mammal species with the 

action; or (4) biological or behavioral 

context of exposure (e.g., age, calving or 

feeding areas); 

• Individual marine mammal 

responses (behavioral or physiological) 

to acoustic stressors (acute, chronic, or 

cumulative), other stressors, or 

cumulative impacts from multiple 

stressors; 

• How anticipated responses to 

stressors impact either: (1) Long-term 

fitness and survival of individual 

marine mammals; or (2) populations, 

species, or stocks; 

• Effects on marine mammal habitat 

(e.g., marine mammal prey species, 

acoustic habitat, or other important 

physical components of marine 

mammal habitat); and 

• Mitigation and monitoring 

effectiveness. 

Vessel-Based Visual Monitoring 

As described above, PSO observations 

would take place during daytime airgun 

operations. During seismic operations, 

at least five visual PSOs would be based 

aboard the Langseth. Two visual PSOs 

would be on duty at all time during 

daytime hours. Monitoring shall be 

conducted in accordance with the 

following requirements: 

• The operator shall provide PSOs 

with bigeye binoculars (e.g., 25 x 150; 

2.7 view angle; individual ocular focus; 

height control) of appropriate quality 

(i.e., Fujinon or equivalent) solely for 

PSO use. These shall be pedestalmounted on the deck at the most 

appropriate vantage point that provides 

for optimal sea surface observation, PSO 

safety, and safe operation of the vessel; 

and 

• The operator will work with the 

selected third-party observer provider to 

ensure PSOs have all equipment 

(including backup equipment) needed 

to adequately perform necessary tasks, 

including accurate determination of 

distance and bearing to observed marine 

mammals. 

PSOs must have the following 

requirements and qualifications: 

• PSOs shall be independent, 

dedicated, trained visual and acoustic 

PSOs and must be employed by a thirdparty observer provider; 

• PSOs shall have no tasks other than 

to conduct observational effort (visual or 

acoustic), collect data, and 

communicate with and instruct relevant 

vessel crew with regard to the presence 

of protected species and mitigation 

requirements (including brief alerts 

regarding maritime hazards); 

• PSOs shall have successfully 

completed an approved PSO training 

course appropriate for their designated 

task (visual or acoustic). Acoustic PSOs 

are required to complete specialized 

training for operating PAM systems and 

are encouraged to have familiarity with 

the vessel with which they will be 

working; 

• PSOs can act as acoustic or visual 

observers (but not at the same time) as 

long as they demonstrate that their 

training and experience are sufficient to 

perform the task at hand; 

• NMFS must review and approve 

PSO resumes accompanied by a relevant 

training course information packet that 

includes the name and qualifications 

(i.e., experience, training completed, or 

educational background) of the 

instructor(s), the course outline or 

syllabus, and course reference material 

as well as a document stating successful 

completion of the course; 

• NMFS shall have one week to 

approve PSOs from the time that the 

necessary information is submitted, 

after which PSOs meeting the minimum 

requirements shall automatically be 

considered approved; 

• PSOs must successfully complete 

relevant training, including completion 

of all required coursework and passing 

(80 percent or greater) a written and/or 

oral examination developed for the 

training program; 

• PSOs must have successfully 

attained a bachelor’s degree from an 

accredited college or university with a 

major in one of the natural sciences, a 

minimum of 30 semester hours or 

equivalent in the biological sciences, 

and at least one undergraduate course in 

math or statistics; and 

• The educational requirements may 

be waived if the PSO has acquired the 

relevant skills through alternate 

experience. Requests for such a waiver 

shall be submitted to NMFS and must 

include written justification. Requests 

shall be granted or denied (with 

justification) by NMFS within one week 

of receipt of submitted information. 

Alternate experience that may be 

considered includes, but is not limited 

to (1) secondary education and/or 

experience comparable to PSO duties; 

(2) previous work experience 

conducting academic, commercial, or 

government-sponsored protected 

species surveys; or (3) previous work 

experience as a PSO; the PSO should 

demonstrate good standing and 

consistently good performance of PSO 

duties. 

For data collection purposes, PSOs 

shall use standardized data collection 

forms, whether hard copy or electronic. 

PSOs shall record detailed information 

about any implementation of mitigation 

requirements, including the distance of 

animals to the acoustic source and 

description of specific actions that 

ensued, the behavior of the animal(s), 

any observed changes in behavior before 

and after implementation of mitigation, 

and if shutdown was implemented, the 

length of time before any subsequent 

ramp-up of the acoustic source. If 

required mitigation was not 

implemented, PSOs should record a 

description of the circumstances. At a 

minimum, the following information 

must be recorded: 

• Vessel names (source vessel and 

other vessels associated with survey) 

and call signs; 

• PSO names and affiliations; 

• Dates of departures and returns to 

port with port name; 

• Date and participants of PSO 

briefings; 

• Dates and times (Greenwich Mean 

Time) of survey effort and times 

corresponding with PSO effort; 

• Vessel location (latitude/longitude) 

when survey effort began and ended and 

vessel location at beginning and end of 

visual PSO duty shifts; 

• Vessel heading and speed at 

beginning and end of visual PSO duty 

shifts and upon any line change; 

• Environmental conditions while on 

visual survey (at beginning and end of 

PSO shift and whenever conditions 

changed significantly), including BSS 

and any other relevant weather 

conditions including cloud cover, fog, 

sun glare, and overall visibility to the 

horizon; 

• Factors that may have contributed 

to impaired observations during each 

PSO shift change or as needed as 

environmental conditions changed (e.g., 

vessel traffic, equipment malfunctions); 

and 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30029 

• Survey activity information, such as 

acoustic source power output while in 

operation, number and volume of 

airguns operating in the array, tow 

depth of the array, and any other notes 

of significance (i.e., pre-start clearance, 

ramp-up, shutdown, testing, shooting, 

ramp-up completion, end of operations, 

streamers, etc.). 

The following information should be 

recorded upon visual observation of any 

protected species: 

• Watch status (sighting made by PSO 

on/off effort, opportunistic, crew, 

alternate vessel/platform); 

• PSO who sighted the animal; 

• Time of sighting; 

• Vessel location at time of sighting; 

• Water depth; 

• Direction of vessel’s travel (compass 

direction); 

• Direction of animal’s travel relative 

to the vessel; 

• Pace of the animal; 

• Estimated distance to the animal 

and its heading relative to vessel at 

initial sighting; 

• Identification of the animal (e.g., 

genus/species, lowest possible 

taxonomic level, or unidentified) and 

the composition of the group if there is 

a mix of species; 

• Estimated number of animals (high/ 

low/best); 

• Estimated number of animals by 

cohort (adults, yearlings, juveniles, 

calves, group composition, etc.); 

• Description (as many distinguishing 

features as possible of each individual 

seen, including length, shape, color, 

pattern, scars or markings, shape and 

size of dorsal fin, shape of head, and 

blow characteristics); 

• Detailed behavior observations (e.g., 

number of blows/breaths, number of 

surfaces, breaching, spyhopping, diving, 

feeding, traveling; as explicit and 

detailed as possible; note any observed 

changes in behavior); 

• Animal’s closest point of approach 

(CPA) and/or closest distance from any 

element of the acoustic source; 

• Platform activity at time of sighting 

(e.g., deploying, recovering, testing, 

shooting, data acquisition, other); and 

• Description of any actions 

implemented in response to the sighting 

(e.g., delays, shutdown, ramp-up) and 

time and location of the action. 

If a marine mammal is detected while 

using the PAM system, the following 

information should be recorded: 

• An acoustic encounter 

identification number, and whether the 

detection was linked with a visual 

sighting; 

• Date and time when first and last 

heard; 

• Types and nature of sounds heard 

(e.g., clicks, whistles, creaks, burst 

pulses, continuous, sporadic, strength of 

signal); and 

• Any additional information 

recorded such as water depth of the 

hydrophone array, bearing of the animal 

to the vessel (if determinable), species 

or taxonomic group (if determinable), 

spectrogram screenshot, and any other 

notable information. 

Reporting 

A report would be submitted to NMFS 

within 90 days after the end of the 

cruise. The report would summarize the 

dates and locations of seismic 

operations, and all marine mammal 

sightings (dates, times, locations, 

activities, associated seismic survey 

activities), and provide full 

documentation of methods, results, and 

interpretation pertaining to all 

monitoring. 

The draft report shall also include 

geo-referenced time-stamped vessel 

tracklines for all time periods during 

which airguns were operating. 

Tracklines should include points 

recording any change in airgun status 

(e.g., when the airguns began operating, 

when they were turned off, or when 

they changed from full array to single 

gun or vice versa). GIS files shall be 

provided in ESRI shapefile format and 

include the UTC date and time, latitude 

in decimal degrees, and longitude in 

decimal degrees. All coordinates shall 

be referenced to the WGS84 geographic 

coordinate system. In addition to the 

report, all raw observational data shall 

be made available to NMFS. The report 

must summarize the data collected as 

described above and in the IHA. A final 

report must be submitted within 30 days 

following resolution of any comments 

on the draft report. 

Reporting Injured or Dead Marine 

Mammals 

Discovery of injured or dead marine 

mammals—In the event that personnel 

involved in survey activities covered by 

the authorization discover an injured or 

dead marine mammal, the L–DEO shall 

report the incident to the Office of 

Protected Resources (OPR), NMFS and 

to the NMFS Alaska Regional Stranding 

Coordinator as soon as feasible. The 

report must include the following 

information: 

• Time, date, and location (latitude/ 

longitude) of the first discovery (and 

updated location information if known 

and applicable); 

• Species identification (if known) or 

description of the animal(s) involved; 

• Condition of the animal(s) 

(including carcass condition if the 

animal is dead); 

• Observed behaviors of the 

animal(s), if alive; 

• If available, photographs or video 

footage of the animal(s); and 

• General circumstances under which 

the animal was discovered. 

Vessel strike—In the event of a ship 

strike of a marine mammal by any vessel 

involved in the activities covered by the 

authorization, L–DEO shall report the 

incident to OPR, NMFS and to the 

NMFS Alaska Regional Stranding 

Coordinator as soon as feasible. The 

report must include the following 

information: 

• Time, date, and location (latitude/ 

longitude) of the incident; 

• Vessel’s speed during and leading 

up to the incident; 

• Vessel’s course/heading and what 

operations were being conducted (if 

applicable); 

• Status of all sound sources in use; 

• Description of avoidance measures/ 

requirements that were in place at the 

time of the strike and what additional 

measure were taken, if any, to avoid 

strike; 

• Environmental conditions (e.g., 

wind speed and direction, Beaufort sea 

state, cloud cover, visibility) 

immediately preceding the strike; 

• Species identification (if known) or 

description of the animal(s) involved; 

• Estimated size and length of the 

animal that was struck; 

• Description of the behavior of the 

animal immediately preceding and 

following the strike; 

• If available, description of the 

presence and behavior of any other 

marine mammals present immediately 

preceding the strike; 

• Estimated fate of the animal (e.g., 

dead, injured but alive, injured and 

moving, blood or tissue observed in the 

water, status unknown, disappeared); 

and 

• To the extent practicable, 

photographs or video footage of the 

animal(s). 

Actions To Minimize Additional Harm 

To Live-Stranded (or Milling) Marine 

Mammals 

In the event of a live stranding (or 

near-shore atypical milling) event 

within 50 km of the survey operations, 

where the NMFS stranding network is 

engaged in herding or other 

interventions to return animals to the 

water, the Director of OPR, NMFS (or 

designee) will advise L–DEO of the need 

to implement shutdown for all active 

acoustic sources operating within 50 km 

of the stranding. Procedures related to 

shutdowns for live stranding or milling 

marine mammals include the following: 

• If at any time, the marine 

mammal(s) die or are euthanized, or if 

30030 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

herding/intervention efforts are stopped, 

the Director of OPR, NMFS (or designee) 

will advise L–DEO that the shutdown 

around the animals’ location is no 

longer needed. 

• Otherwise, shutdown procedures 

will remain in effect until the Director 

of OPR, NMFS (or designee) determines 

and advises L–DEO that all live animals 

involved have left the area (either of 

their own volition or following an 

intervention). 

• If further observations of the marine 

mammals indicate the potential for restranding, additional coordination with 

L–DEO will be required to determine 

what measures are necessary to 

minimize that likelihood (e.g., 

extending the shutdown or moving 

operations farther away) and to 

implement those measures as 

appropriate. 

Additional Information Requests—If 

NMFS determines that the 

circumstances of any marine mammal 

stranding found in the vicinity of the 

activity suggest investigation of the 

association with survey activities is 

warranted, and an investigation into the 

stranding is being pursued, NMFS will 

submit a written request to L–DEO 

indicating that the following initial 

available information must be provided 

as soon as possible, but no later than 7 

business days after the request for 

information: 

• Status of all sound source use in the 

48 hours preceding the estimated time 

of stranding and within 50 km of the 

discovery/notification of the stranding 

by NMFS; and 

• If available, description of the 

behavior of any marine mammal(s) 

observed preceding (i.e., within 48 

hours and 50 km) and immediately after 

the discovery of the stranding. 

In the event that the investigation is 

still inconclusive, the investigation of 

the association of the survey activities is 

still warranted, and the investigation is 

still being pursued, NMFS may provide 

additional information requests, in 

writing, regarding the nature and 

location of survey operations prior to 

the time period above. 

Negligible Impact Analysis and 

Determination 

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., populationlevel 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’’ 

through harassment, NMFS considers 

other factors, such as the likely nature 

of any responses (e.g., intensity, 

duration), 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’s 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, ongoing 

sources of human-caused mortality, or 

ambient noise levels). 

To avoid repetition, our analysis 

applies to all species listed in Table 1, 

given that NMFS expects the anticipated 

effects of the planned geophysical 

survey to be similar in nature. Where 

there are meaningful differences 

between species or stocks, or groups of 

species, in anticipated individual 

responses to activities, impact of 

expected take on the population due to 

differences in population status, or 

impacts on habitat, NMFS has identified 

species-specific factors to inform the 

analysis. 

As described above, we propose to 

authorize only the takes estimated to 

occur outside of Canadian territorial 

waters (Table 7); however, for the 

purposes of our negligible impact 

analysis and determination, we consider 

the total number of takes that are 

anticipated to occur as a result of the 

entire survey (including the portion of 

the survey that would occur within the 

Canadian territorial waters 

(approximately 13 percent of the survey) 

(Table 8). 

TABLE 8—TOTAL ESTIMATED TAKE INCLUDING CANADIAN TERRITORIAL WATERS

Species 

Level B 

harassment 

(excluding 

Canadian 

territorial 

waters) 

Level A 

harassment 

(excluding 

Canadian 

territorial 

waters) 

Level B 

harassment 

(Canadian 

territorial 

waters) 

Level A 

harassment 

(Canadian 

territorial 

waters) 

Total 

Level B 

harassment 

Total 

Level A 

harassment 

Gray whale, WNP ............................................................................................. 2 0 1 0 3 0 

Gray whale, ENP .............................................................................................. 1,448 45 666 16 2,114 61 

Humpback whale ............................................................................................... 403 14 165 4 568 18 

Blue whale ......................................................................................................... 31 1 4 0 35 1 

Fin whale ........................................................................................................... 873 44 69 1 942 45 

Sei whale ........................................................................................................... 34 1 7 0 41 1 

Minke whale ...................................................................................................... 57 2 14 0 71 2

Sperm whale ..................................................................................................... 131 0 22 0 153 0 

Baird’s beaked whale ........................................................................................ 29 0 2 0 31 0 

Stejneger’s beaked whale ................................................................................. 120 0 9 0 129 0 

Cuvier’s beaked whale ...................................................................................... 114 0 9 0 123 0 

Pacific white-sided dolphin ................................................................................ 1,374 0 191 0 1,565 0 

Northern right whale dolphin ............................................................................. 927 0 451 0 1,378 0 

Risso’s dolphin .................................................................................................. 22 0 22 0 44 0

Killer whale ........................................................................................................ 290 0 89 0 379 0 

Dall’s porpoise ................................................................................................... 5,661 178 1,825 36 7,486 214 

Harbor porpoise ................................................................................................ 990 26 455 9 1,445 35 

Northern fur seal ............................................................................................... 5,812 0 1,213 0 7,025 0 

California sea lion ............................................................................................. 1,258 0 433 0 1,691 0 

Steller sea lion, wDPS ...................................................................................... 54 0 55 0 109 0 

Steller sea lion, eDPS ....................................................................................... 2,381 0 2,467 0 4,848 0 

Northern elephant seal ...................................................................................... 6,850 0 1,429 0 8,279 0 

Harbor seal ........................................................................................................ 6,012 0 6,228 0 12,240 0 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30031 

NMFS does not anticipate that serious 

injury or mortality would occur as a 

result of L–DEO’s planned survey, even 

in the absence of mitigation, and none 

would be authorized. Similarly, nonauditory physical effects, stranding, and 

vessel strike are not expected to occur. 

We are proposing to authorize a 

limited number of instances of Level A 

harassment of seven species (low- and 

high-frequency cetacean hearing groups 

only) and Level B harassment only of 

the remaining marine mammal species. 

However, we believe that any PTS 

incurred in marine mammals as a result 

of the planned activity would be in the 

form of only a small degree of PTS, not 

total deafness, because of the constant 

movement of both the R/V Langseth and 

of the marine mammals in the project 

areas, as well as the fact that the vessel 

is not expected to remain in any one 

area in which individual marine 

mammals would be expected to 

concentrate for an extended period of 

time. Since the duration of exposure to 

loud sounds will be relatively short it 

would be unlikely to affect the fitness of 

any individuals. Also, as described 

above, we expect that marine mammals 

would likely move away from a sound 

source that represents an aversive 

stimulus, especially at levels that would 

be expected to result in PTS, given 

sufficient notice of the R/V Langseth’s 

approach due to the vessel’s relatively 

low speed when conducting seismic 

surveys. We expect that the majority of 

takes would be in the form of short-term 

Level B behavioral harassment in the 

form of temporary avoidance of the area 

or decreased foraging (if such activity 

were occurring), reactions that are 

considered to be of low severity and 

with no lasting biological consequences 

(e.g., Southall et al., 2007, Ellison et al., 

2012). 

Marine mammal habitat may be 

impacted by elevated sound levels, but 

these impacts would be temporary. Prey 

species are mobile and are broadly 

distributed throughout the project areas; 

therefore, marine mammals that may be 

temporarily displaced during survey 

activities are expected to be able to 

resume foraging once they have moved 

away from areas with disturbing levels 

of underwater noise. Because of the 

relatively short duration (27 days) and 

temporary nature of the disturbance, the 

availability of similar habitat and 

resources in the surrounding area, the 

impacts to marine mammals and the 

food sources that they utilize are not 

expected to cause significant or longterm consequences for individual 

marine mammals or their populations. 

The tracklines of this survey either 

traverse or are proximal to critical 

habitat for the Mexico DPS of humpback 

whales and for Steller sea lions, and to 

feeding BIAs for humpback whales in 

general (including both the Hawaii and 

Mexico DPSs/Central North Pacific 

stock whales that are anticipated to 

occur in the survey area). As described 

previously, the survey area is near a 

feeding BIA for gray whales and covers 

the gray whale migratory BIA. However, 

these BIAs would not be affected as they 

are spatially and temporally separated, 

respectively, from the survey. 

Yazvenko et al. (2007) reported no 

apparent changes in the frequency of 

feeding activity in Western gray whales 

exposed to airgun sounds in their 

feeding grounds near Sakhalin Island. 

Goldbogen et al. (2013) found blue 

whales feeding on highly concentrated 

prey in shallow depths (such as the 

conditions expected within humpback 

feeding BIAs) were less likely to 

respond and cease foraging than whales 

feeding on deep, dispersed prey when 

exposed to simulated sonar sources, 

suggesting that the benefits of feeding 

for humpbacks foraging on high-density 

prey may outweigh perceived harm 

from the acoustic stimulus, such as the 

seismic survey (Southall et al., 2016). 

Additionally, L–DEO will shut down 

the airgun array upon observation of an 

aggregation of six or more large whales, 

which would reduce impacts to 

cooperatively foraging animals. For all 

habitats, no physical impacts to habitat 

are anticipated from seismic activities. 

While SPLs of sufficient strength have 

been known to cause injury to fish and 

fish and invertebrate mortality, in 

feeding habitats, the most likely impact 

to prey species from survey activities 

would be temporary avoidance of the 

affected area and any injury or mortality 

of prey species would be localized 

around the survey and not of a degree 

that would adversely impact marine 

mammal foraging. 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 expected. 

Given the short operational seismic time 

near or traversing important habitat 

areas, as well as the ability of cetaceans 

and prey species to move away from 

acoustic sources, NMFS expects that 

there would be, at worst, minimal 

impacts to animals and habitat within 

these areas. 

Critical habitat for Steller sea lions 

has been established at three rookeries 

in southeast Alaska (Hazy Island, White 

Sisters Island, and Forrester Island near 

Dixon Entrance), at several major haulouts, and including aquatic zones that 

extend 0.9 km seaward and air zones 

extending 0.9 km above the rookeries. 

Steller sea lions occupy rookeries and 

pup from late-May through early-July 

(NMFS. 2008), indicating that L–DEO’s 

survey is unlikely to impact important 

sea lion behaviors in critical habitat. 

Impacts to Steller sea lions within these 

areas, and throughout the survey area, 

as well as impacts to other pinniped 

species, are expected to be limited to 

short-term behavioral disturbance, with 

no lasting biological consequences. 

Negligible Impact Conclusions 

The proposed survey would be of 

short duration (27 days of seismic 

operations), and the acoustic ‘‘footprint’’ 

of the proposed survey would be small 

relative to the ranges of the marine 

mammals that would potentially be 

affected. Sound levels would increase in 

the marine environment in a relatively 

small area surrounding the vessel 

compared to the range of the marine 

mammals within the proposed survey 

area. Short term exposures to survey 

operations are not likely to significantly 

disrupt marine mammal behavior, and 

the potential for longer-term avoidance 

of important areas is limited. 

The proposed mitigation measures are 

expected to reduce the number and/or 

severity of takes by allowing for 

detection of marine mammals in the 

vicinity of the vessel by visual and 

acoustic observers, and by minimizing 

the severity of any potential exposures 

via shutdowns of the airgun array. 

Based on previous monitoring reports 

for substantially similar activities that 

have been previously authorized by 

NMFS, we expect that the proposed 

mitigation will be effective in 

preventing, at least to some extent, 

potential PTS in marine mammals that 

may otherwise occur in the absence of 

the proposed mitigation (although all 

authorized PTS has been accounted for 

in this analysis). 

NMFS concludes that exposures to 

marine mammal species and stocks due 

to L–DEO’s proposed survey would 

result in only short-term (temporary and 

short in duration) effects to individuals 

exposed, over relatively small areas of 

the affected animals’ ranges. Animals 

may temporarily avoid the immediate 

area, but are not expected to 

permanently abandon the area. Major 

shifts in habitat use, distribution, or 

foraging success are not expected. 

NMFS does not anticipate the proposed 

take estimates to impact annual rates of 

recruitment or survival. 

In summary and as described above, 

the following factors primarily support 

our preliminary determination that the 

impacts resulting from this activity are 

not expected to adversely affect the 

30032 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

species or stock through effects on 

annual rates of recruitment or survival: 

• No serious injury or mortality is 

anticipated or proposed to be 

authorized; 

• The proposed activity is temporary 

and of relatively short duration (27 

days); 

• The anticipated impacts of the 

proposed activity on marine mammals 

would primarily be temporary 

behavioral changes due to avoidance of 

the area around the survey vessel; 

• The number of instances of 

potential PTS that may occur are 

expected to be very small in number. 

Instances of potential PTS that are 

incurred in marine mammals are 

expected to be of a low level, due to 

constant movement of the vessel and of 

the marine mammals in the area, and 

the nature of the survey design (not 

concentrated in areas of high marine 

mammal concentration); 

• The availability of alternate areas of 

similar habitat value for marine 

mammals to temporarily vacate the 

survey area during the proposed survey 

to avoid exposure to sounds from the 

activity; 

• The potential adverse effects on fish 

or invertebrate species that serve as prey 

species for marine mammals from the 

proposed survey would be temporary 

and spatially limited, and impacts to 

marine mammal foraging would be 

minimal; and 

• The proposed mitigation measures, 

including visual and acoustic 

monitoring and shutdowns are expected 

to minimize potential impacts to marine 

mammals (both amount and severity). 

Based on the analysis contained 

herein of the likely effects of the 

specified activity on marine mammals 

and their habitat, and taking into 

consideration the implementation of the 

proposed mitigation and monitoring 

measures, NMFS preliminarily finds 

that the total marine mammal take from 

the proposed activity will have a 

negligible impact on all affected marine 

mammal species or stocks. 

Small Numbers 

As noted above, only small numbers 

of incidental take may be authorized 

under Sections 101(a)(5)(A) and (D) of 

the MMPA for specified activities other 

than military readiness activities. The 

MMPA does not define small numbers 

and so, in practice, where estimated 

numbers are available, NMFS compares 

the number of individuals taken to the 

most appropriate estimation of 

abundance of the relevant species or 

stock in our determination of whether 

an authorization is limited to small 

numbers of marine mammals. When the 

predicted number of individuals to be 

taken is fewer than one-third of the 

species or stock abundance, the take is 

considered to be of small numbers. 

Additionally, other qualitative factors 

may be considered in the analysis, such 

as the temporal or spatial scale of the 

activities. 

There are several stocks for which the 

estimated instances of take appear high 

when compared to the stock abundance 

(Table 7), or for which there is no 

currently accepted stock abundance 

estimate. These include the fin whale, 

minke whale, sperm whale, three 

species of beaked whale, four stocks of 

killer whales, harbor porpoise, and one 

stock of harbor seal. However, when 

other qualitative factors are used to 

inform an assessment of the likely 

number of individual marine mammals 

taken, the resulting numbers are 

appropriately considered small. We 

discuss these in further detail below. 

For all other stocks (aside from those 

referenced above and discussed below), 

the proposed take is less than one-third 

of the best available stock abundance 

(recognizing that some of those takes 

may be repeats of the same individual, 

thus rendering the actual percentage 

even lower), and noting that we 

generally excluded consideration of 

abundance information for British 

Columbia in considering the amount of 

take relative to the best available stock 

abundance information. 

The stock abundance estimates for the 

fin, minke, beaked, and sperm whale 

stocks that occur in the survey area are 

unknown, according to the latest SARs. 

The same is true for the harbor porpoise. 

Therefore, we reviewed other scientific 

information in making our small 

numbers determinations for these 

species. As noted previously, partial 

abundance estimates of 1,233 and 2,020 

minke whales are available for shelf and 

nearshore waters between the Kenai 

Peninsula and Amchitka Pass and for 

the eastern Bering Sea shelf, 

respectively. For the minke whale, these 

partial abundance estimates alone are 

sufficient to demonstrate that the 

proposed take number of 59 is of small 

numbers. The same surveys produced 

partial abundance estimates of 1,652 

and 1,061 fin whales, for the same areas, 

respectively. Considering these two 

partial abundance estimates in 

conjunction with the British Columbia 

abundance estimate of 329 whales 

produces a total partial estimate of 3,042 

whales for shelf and nearshore waters 

between the Kenai Peninsula and 

Amchitka Pass, the eastern Bering Sea 

shelf, and British Columbia. Given that 

the Northeast Pacific stock of fin 

whale’s range is described as covering 

the entire GOA and Bering Sea, we 

reasonably assume that a total 

abundance estimate for the stock would 

show that the take number proposed for 

authorization (917) is small. In addition, 

for these stocks as well as for other 

stocks discussed below whose range 

spans the GOA, given that the estimated 

take will take place in a relatively small 

portion of the stock’s range, it is likely 

there would be repeat takes of a smaller 

number of individuals, and therefore, 

the number of individual animals taken 

will be lower. 

As noted previously, Kato and 

Miyashita (1998) produced an 

abundance estimate of 102,112 sperm 

whales in the western North Pacific. 

However, this estimate is believed to be 

positively biased. We therefore refer to 

Barlow and Taylor (2005)’s estimate of 

26,300 sperm whales in the northeast 

temperate Pacific to demonstrate that 

the proposed take number of 136 is a 

small number. There is no abundance 

information available for any Alaskan 

stock of beaked whale. However, the 

take numbers are sufficiently small 

(ranging from 29–120) that we can safely 

assume that they are small relative to 

any reasonable assumption of likely 

population abundance for these stocks. 

As an example, we review available 

abundance information for other stocks 

of Cuvier’s beaked whales, which is 

widely distributed throughout deep 

waters of all oceans and is typically the 

most commonly encountered beaked 

whale in its range. Where some degree 

of bias correction, which is critical to an 

accurate abundance estimate for cryptic 

species like beaked whales, is 

incorporated to the estimate, we see 

typical estimates in the thousands of 

animals, demonstrating that the take 

numbers proposed for authorization are 

reasonably considered small. Current 

abundance estimates include the 

Western North Atlantic stock (5,744 

animals; CV = 0.36), the Hawaii Pelagic 

stock (4,431 animals, CV = 0.41), and 

the California/Oregon/Washington stock 

(3,274 animals; CV = 0.67). 

For the southeast Alaska stock of 

harbor porpoise, whose range is defined 

as from Dixon Entrance to Cape 

Suckling (including inland waters), the 

SAR describes a partial abundance 

estimate, covering inland waters but not 

coastal waters, totaling 1,354 porpoise. 

This most recent abundance estimate is 

based on survey effort in inland waters 

during 2010–12 (Dahlheim et al., 2015). 

An older abundance estimate, based on 

survey effort conducted in 1997, 

covering both coastal and inland waters 

of the stock’s range, provides a more 

complete abundance estimate of 11,146 

animals (Hobbs and Waite, 2010). This 

Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 30033 

estimate is sufficient to demonstrate that 

the take number proposed for 

authorization (1,016) is small. 

For the potentially affected stocks of 

killer whale, it would be unreasonable 

to assume that all takes would accrue to 

any one stock. Although the Gulf of 

Alaska, Aleutian Islands, and Bering Sea 

(GOA/BSAI) transient stock could occur 

in southeast Alaska, it is unlikely that 

any significant proportion of 

encountered whales would belong to 

this stock, which is generally 

considered to occur mainly from Prince 

William Sound through the Aleutian 

Islands and Bering Sea. Transient killer 

whales in Canadian waters are 

considered part of the West Coast 

transient stock, further minimizing the 

potential for encounter with the GOA/ 

BSAI transient stock. We assume that 

only nominal, if any, take would 

actually accrue to this stock. Similarly, 

the offshore stock is encountered only 

rarely compared with resident and 

transient stocks. Seasonal sighting data 

collected in southeast Alaska waters 

between 1991 and 2007 shows a ratio of 

offshore and resident killer whale 

sightings of 0.05 (Dahlheim et al., 2009), 

and it is unlikely that any amount of 

take accruing to this stock would exceed 

small numbers. We anticipate that most 

killer whales encountered would be 

transient or resident whales. For the 

remaining stocks, we assume that take 

would accrue to each stock in a manner 

roughly approximate to the stocks’ 

relative abundances, i.e., 78 percent 

Alaska resident, 12 percent West Coast 

transient, and 10 percent northern 

resident. This would equate to 

approximately 226 takes from the 

Alaska resident stock (9.6 percent of the 

stock abundance); 35 takes from the 

West Coast transient stock (10 percent of 

the stock abundance), and 29 takes from 

the northern resident stock (9.6 percent 

of the stock abundance). Based on the 

assumptions described in this 

paragraph, we preliminary find that the 

taking proposed for authorization is of 

no greater than small numbers for any 

stock of killer whale. 

If all takes proposed for authorization 

are allotted to each individual harbor 

seal stock, the estimated instances of 

take would be greater than one-third of 

the best available abundance estimate 

for the Sitka/Chatham Strait stock of 

harbor seal. However, similarly to the 

discussion provided above for killer 

whale, it would be unreasonable to 

assume that all takes would accrue to 

any one stock. Based on the location of 

the proposed survey relative to the 

potentially affected stocks’ ranges, it is 

unlikely that a significant proportion of 

the estimated takes would occur to the 

Sitka/Chatham Strait stock (whose range 

just overlaps with the northern extent of 

the survey area) (Muto et al., 2020). A 

majority of takes are likely to accrue to 

the Dixon/Cape Decision stock, which 

most directly overlaps with the 

proposed survey area. In the unlikely 

event that all takes occurred to the 

Dixon/Cape Decision stock, the amount 

of take would be of small numbers. 

Based on the analysis contained 

herein of the proposed activity 

(including the proposed mitigation and 

monitoring measures) and the 

anticipated take of marine mammals, 

NMFS preliminarily finds that small 

numbers of marine mammals will be 

taken relative to the population size of 

the affected species or stocks. 

Unmitigable Adverse Impact Analysis 

and Determination 

Marine mammals are legally hunted 

in Alaskan waters by coastal Alaska 

Natives. In the GOA, the only marine 

mammals under NMFS’ jurisdiction that 

are currently hunted are Steller sea lions 

and harbor seals. These species are an 

important subsistence resource for 

Alaska Natives from southeast Alaska to 

the Aleutian Islands. There are 

numerous communities along the shores 

of the GOA that participate in 

subsistence hunting, including Juneau, 

Ketchikan, Sitka, and Yakutat in 

southeast Alaska (Wolfe et al., 2013). 

According to Muto et al. (2019), the 

annual subsistence take of Steller sea 

lions from the eastern stock was 11, and 

415 northern fur seals are taken 

annually. In addition, 340 harbor seals 

are taken annually (Muto et al. 2019). 

The seal harvest throughout Southeast 

Alaska is generally highest during 

spring and fall, but can occur any time 

of the year (Wolfe et al., 2013). 

Given the temporary nature of the 

proposed activities and the fact that 

most operations would occur further 

from shore, the proposed activity would 

not be expected to have any impact on 

the availability of the species or stocks 

for subsistence users. L–DEO is 

conducting outreach to local 

stakeholders, including subsistence 

communities, to notify subsistence 

hunters of the planned survey, to 

identify the measures that would be 

taken to minimize any effects on the 

availability of marine mammals for 

subsistence uses, and to provide an 

opportunity for comment on these 

measures. During operations, radio 

communications and Notice to Mariners 

would keep interested parties apprised 

of vessel activities. NMFS is unaware of 

any other subsistence uses of the 

affected marine mammal stocks or 

species that could be implicated by this 

action. Therefore, NMFS has 

preliminarily 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. NMFS requests 

comments or any information that may 

help to inform this determination. 

Endangered Species Act (ESA) 

Section 7(a)(2) of the ESA of 1973 (16 

U.S.C. 1531 et seq.) requires that each 

Federal agency insure that any action it 

authorizes, funds, or carries out is not 

likely to jeopardize the continued 

existence of any endangered or 

threatened species or result in the 

destruction or adverse modification of 

designated critical habitat. To ensure 

ESA compliance for the issuance of 

IHAs, NMFS consults internally 

whenever we propose to authorize take 

for endangered or threatened species. 

NMFS is proposing to authorize take 

of blue whales, fin whales, sei whales, 

sperm whales, Mexico DPS humpback 

whales, western DPS Steller sea lions, 

and WNP gray whales, which are listed 

under the ESA. The NMFS OPR Permits 

and Conservation Division has 

requested initiation of Section 7 

consultation with the NMFS OPR ESA 

Interagency Cooperation Division for the 

issuance of this IHA. NMFS will 

conclude the ESA consultation prior to 

reaching a determination regarding the 

proposed issuance of the authorization. 

Proposed Authorization 

As a result of these preliminary 

determinations, NMFS proposes to issue 

an IHA to L–DEO for conducting a 

marine geophysical survey in the 

northeast Pacific beginning in July 2021, 

provided the previously mentioned 

mitigation, monitoring, and reporting 

requirements are incorporated. A draft 

of the proposed IHA can be found at 

www.fisheries.noaa.gov/permit/ 

incidental-take-authorizations-undermarine-mammal-protection-act. 

Request for Public Comments 

We request comment on our analyses, 

the proposed authorization, and any 

other aspect of this notice of Proposed 

IHA for the proposed geophysical 

survey. We also request at this time 

comment on the potential Renewal of 

this proposed IHA as described in the 

paragraph below. Please include with 

your comments any supporting data or 

literature citations to help inform 

decisions on the request for this IHA or 

a subsequent Renewal IHA. 

On a case-by-case basis, NMFS may 

issue a one-time, one-year Renewal IHA 

following notice to the public providing 

30034 Federal Register / Vol. 86, No. 106 / Friday, June 4, 2021 / Notices 

an additional 15 days for public 

comments when (1) up to another year 

of identical, or nearly identical, 

activities as described in the Description 

of Proposed Activity section of this 

notice is planned or (2) the activities as 

described in the Description of 

Proposed Activity section of this notice 

would not be completed by the time the 

IHA expires and a Renewal would allow 

for completion of the activities beyond 

that described in the Dates and Duration 

section of this notice, provided all of the 

following conditions are met: 

• A request for renewal is received no 

later than 60 days prior to the needed 

Renewal IHA effective date (recognizing 

that the Renewal IHA expiration date 

cannot extend beyond one year from 

expiration of the initial IHA); 

• The request for renewal must 

include the following: 

(1) An explanation that the activities 

to be conducted under the requested 

Renewal IHA are identical to the 

activities analyzed under the initial 

IHA, are a subset of the activities, or 

include changes so minor (e.g., 

reduction in pile size) that the changes 

do not affect the previous analyses, 

mitigation and monitoring 

requirements, or take estimates (with 

the exception of reducing the type or 

amount of take); and 

(2) A preliminary monitoring report 

showing the results of the required 

monitoring to date and an explanation 

showing that the monitoring results do 

not indicate impacts of a scale or nature 

not previously analyzed or authorized. 

• Upon review of the request for 

Renewal, the status of the affected 

species or stocks, and any other 

pertinent information, NMFS 

determines that there are no more than 

minor changes in the activities, the 

mitigation and monitoring measures 

will remain the same and appropriate, 

and the findings in the initial IHA 

remain valid. 

Dated: May 28, 2021. 

Catherine Marzin, 

Acting Director, Office of Protected Resources, 

National Marine Fisheries Service. 

[FR Doc. 2021–11718 Filed 6–3–21; 8:45 am] 

BILLING CODE 3510–22–P 

DEPARTMENT OF COMMERCE 

National Oceanic and Atmospheric 

Administration 

Withdrawal of Notice of Intent To 

Prepare an Environmental Impact 

Statement for Monterey Bay Regional 

Water Project Desalination Facility 

AGENCY: Office of National Marine 

Sanctuaries (ONMS), National Ocean 

Service (NOS), National Oceanic and 

Atmospheric Administration (NOAA), 

Department of Commerce (DOC). 

ACTION: Withdrawal of notice of intent 

to prepare an environmental impact 

statement. 

SUMMARY: NOAA’s Office of National 

Marine Sanctuaries is issuing this notice 

to advise Federal, state, and local 

government agencies and the public that 

it is withdrawing its Notice of Intent to 

prepare a draft environmental impact 

statement for the proposed action to 

construct and operate a seawater reverse 

osmosis desalination facility and colocated seawater-cooled 150-megawatt 

computer data center campus project at 

Moss Landing, Monterey County, 

California. NOAA is terminating the 

review of this project under the National 

Environmental Policy Act because the 

proposed project scope has changed 

significantly. 

FOR FURTHER INFORMATION CONTACT: 

Karen Grimmer, Resource Protection 

Coordinator, Monterey Bay National 

Marine Sanctuary, at karen.grimmer@

noaa.gov, or by mail at 99 Pacific Street, 

Suite 455A, Monterey, California 93940. 

SUPPLEMENTARY INFORMATION: NOAA 

published a Notice of Intent (NOI) in the 

Federal Register on June 1, 2015 (80 FR 

31022), to prepare a joint environmental 

impact report (EIR)/environmental 

impact statement (EIS) with the 

California State Lands Commission 

(CSLC) in accordance with the National 

Environmental Policy Act (NEPA) and 

the California Environmental Quality 

Act. The joint EIR/EIS would have 

analyzed the impacts on the human 

environment resulting from DeepWater 

Desal’s construction and operation of a 

seawater reverse osmosis (SWRO) 

desalination facility and co-located 

seawater-cooled 150-megawatt 

computer data center campus project 

(Project) at Moss Landing, Monterey 

County, California. 

DeepWater Desal submitted an 

application for permit approval to 

Monterey Bay National Marine 

Sanctuary to construct and operate a 

SWRO desalination facility capable of 

producing 25,000 acre-feet per year of 

potable water and a co-located seawatercooled computer data center campus on 

a 110-acre site located approximately 

1.5 miles east of Moss Landing. 

Additional details about the Project are 

included in the NOI dated June 1, 2015. 

NOAA solicited public input on the 

scope of the analysis through a public 

comment period on the NOI from June 

1, 2015, to July 1, 2015. NOAA received 

six comments in response to the notice, 

which are publicly available on http:// 

www.regulations.gov under docket 

NOAA–NOS–2015–0069. NOAA and 

CSLC held a joint public scoping 

meeting for the project on Tuesday, June 

16, 2015, and six commenters provided 

testimony. 

NOAA is terminating the NEPA 

process and closing the Project’s permit 

application because the permit 

applicant notified NOAA in May 2020 

that the primary scope of the Project 

changed from desalination to land-based 

aquaculture. NOAA finds that the scope 

of the Project has changed significantly 

since publication of the 2015 NOI and 

the scoping process completed in 2015 

is no longer relevant. Therefore, NOAA 

is withdrawing the NOI to prepare an 

EIS for this Project. Should NOAA 

receive a new permit application, 

NOAA will determine at that time what 

level of NEPA review is required for the 

project. 

Authority: 16 U.S.C. 1431 et seq.; 40 CFR 

1500–1508; Companion Manual for NOAA 

Administrative Order 216–6A, 82 FR 4306. 

John Armor, 

Director, Office of National Marine 

Sanctuaries National Ocean Service, National 

Oceanic and Atmospheric Administration. 

[FR Doc. 2021–11714 Filed 6–3–21; 8:45 am] 

BILLING CODE 3510–NK–P 

COMMITTEE FOR PURCHASE FROM 

PEOPLE WHO ARE BLIND OR 

SEVERELY DISABLED 

Procurement List; Deletions 

AGENCY: Committee for Purchase From 

People Who Are Blind or Severely 

Disabled 

ACTION: Deletions from the procurement 

list. 

SUMMARY: This action deletes product(s) 

from the Procurement List previously 

furnished by nonprofit agencies 

employing persons who are blind or 

have other severe disabilities. 

DATES: Date deleted from the 

Procurement List: July 04, 2021. 

ADDRESSES: Committee for Purchase 

From People Who Are Blind or Severely 

Disabled, 1401 S Clark Street, Suite 715, 

Arlington, Virginia 22202–4149.