[Federal Register Volume 86, Number 96 (Thursday, May 20, 2021)]
[Notices]
[Pages 27393-27410]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-10551]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XB056]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Site Characterization Surveys Off 
the Coast of Massachusetts

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

ACTION: Notice; modified proposal of an incidental harassment 
authorization; request for comments on modified proposed authorization 
and possible renewal.

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SUMMARY: NMFS has received a request from Mayflower Wind Energy LLC 
(Mayflower) for authorization to take marine mammals incidental to site 
characterization surveys off the coast of Massachusetts in the area of 
the Commercial Lease of Submerged Lands for Renewable Energy 
Development on the Outer Continental Shelf (OCS-A 0521) and along 
potential submarine cable routes to landfall locations at Falmouth, 
Massachusetts and near

[[Page 27394]]

Narragansett Bay. NMFS published a proposed incidental harassment 
authorization (IHA) in the Federal Register on March 1, 2021, Mayflower 
determined that they needed to add an additional export cable route 
corridor to the proposed IHA. Therefore, a final IHA was not issued and 
Mayflower submitted a modified application on April 19, 2021. Pursuant 
to the Marine Mammal Protection Act (MMPA), NMFS is requesting comments 
on its modified 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-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.

ADDRESSES: Comments should be addressed to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service, and should be submitted via email to 
[email protected].
    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, including all attachments, must 
not exceed a 25-megabyte file size. All comments received are a part of 
the public record and will generally be posted online at 
www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-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: Robert Pauline, 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: https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-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 
incidental harassment authorization) with respect to potential impacts 
on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (incidental harassment authorizations with 
no anticipated serious injury or mortality) of the Companion Manual for 
NOAA Administrative Order 216-6A, which do not individually or 
cumulatively have the potential for significant impacts on the quality 
of the human environment and for which NMFS has not identified any 
extraordinary circumstances that would preclude this categorical 
exclusion. Accordingly, NMFS has preliminarily determined that the 
issuance of the proposed IHA qualifies to be categorically excluded 
from further NEPA review.
    NMFS 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 October 23, 2020, NMFS received a request from Mayflower for an 
IHA to take marine mammals incidental to site characterization surveys 
in the area of the Commercial Lease of Submerged Lands for Renewable 
Energy Development on the Outer Continental Shelf (OCS-A 0521; Lease 
Area) and a submarine export cable route connecting the Lease Area to a 
landfall location in Falmouth, Massachusetts. A revised application was 
received on December 15, 2020. NMFS deemed that request to be adequate 
and complete on February 1, 2021. Mayflower's request was for take of a 
small number of 14 species of marine mammals by Level B harassment 
only. Neither Mayflower nor NMFS expected serious injury or mortality 
to result from this activity and, therefore, an IHA was appropriate. 
NMFS published a notice of proposed IHA in the Federal Register on 
March 1, 2021 (86 FR 11930).
    Mayflower submitted a modified application on April 19, 2021 after 
the initial proposed IHA had published in the Federal Register. A final 
IHA was not issued for the initial proposed IHA. The modified 
application included an additional export cable route. Mayflower 
originally had proposed two separate but parallel export cable routes 
that would run north from the Lease Area between Martha's Vineyard and 
Nantucket islands through Nantucket Sound to a landfall location in 
Falmouth, MA. As part of the modification, Mayflower proposes to 
eliminate the easternmost export cable corridor route between Martha's 
Vineyard and Nantucket and replace it with an export cable corridor 
route that runs south of Martha's Vineyard through Narragansett Bay to 
an unspecified landfall location in the Bay. The westernmost export 
cable route corridor to Falmouth, MA would remain unchanged from the 
initial proposed IHA.
    NMFS previously issued an IHA to Mayflower for similar work (85 FR 
45578; July 29, 2020) in the same Lease Area and along the same 
submarine cable route that runs between Martha's Vineyard and Nantucket 
to a landfall location in Falmouth, MA that is currently effective from 
July 23, 2020 through July 22, 2021.

[[Page 27395]]

Description of Proposed Activity

Overview

    Mayflower proposes to conduct marine site characterization surveys, 
including high-resolution geophysical (HRG) and geotechnical surveys, 
in the area of Commercial Lease of Submerged Lands for Renewable Energy 
Development on the Outer Continental Shelf #OCS-A 0521 (Lease Area) and 
along potential submarine cable routes to landfall locations at 
Falmouth, Massachusetts and in Narragansett Bay as shown in Figure 1.
[GRAPHIC] [TIFF OMITTED] TN20MY21.001

    The objective of the activities is to acquire high resolution 
geophysical (HRG) and geotechnical data on the bathymetry, seafloor 
morphology, subsurface geology, environmental/biological sites, 
seafloor obstructions, soil conditions, and locations of any man-made, 
historical or archaeological resources within Lease Area OCS-A 0521 and 
along the proposed export cable route corridors.
    HRG surveys would be carried out by up to four (4) different 
vessels. This is the same number of vessels that was proposed in the 
initial application and notice of proposed IHA (86 FR 11930; March 1, 
2021).
    Underwater sound resulting from Mayflower's proposed activities, 
specifically its proposed HRG surveys, have the potential to result in 
incidental take of marine mammals in the form of behavioral harassment.

Dates and Duration

    The total duration of the modified proposed HRG survey activities 
would be approximately 471 survey days and the total trackline distance 
would be 14,350 kilometers (km) as shown in Table 1. These values are 
identical to those presented in the initial proposed IHA (86 FR 11930; 
March 1, 2021).
    Mayflower deducted the trackline distance from the eastern cable 
route that was originally running to Falmouth as well as selected 
trackline distances originally planned for the Lease Area, and added 
these same trackline distances to the new proposed Narragansett Bay 
cable route corridor. Mayflower proposes to begin survey activities in 
June 2021 and conclude operations by December 31, 2021. However, the 
modified proposed IHA would be effective for 1 year from the date of 
issuance. In the initial proposed IHA, Mayflower had proposed effective 
dates of April 1, 2021 through November 30, 2021.

Specific Geographic Region

    Mayflower's survey activities would occur in the Northwest Atlantic 
Ocean in Lease Area OCS-A 0521 which is located approximately 20 
nautical miles (38 km) south-southwest of Nantucket, Massachusetts and 
covers approximately 515 km\2\. All survey efforts would occur within 
U.S. Federal and state waters. Water depths in the Lease Area are 
approximately 38-62 meters (m). For the purpose of this IHA,

[[Page 27396]]

the Lease Area and export cable routes are collectively referred to as 
the Project Area.

Detailed Description of Specific Activity

    Mayflower's modified proposed marine site characterization surveys 
include the use of HRG survey equipment. Survey activities would occur 
within the Lease Area and along export cable routes between the Lease 
Area and Falmouth, MA and Narragansett Bay. Up to four (HRG survey 
vessels may operate concurrently as part of the proposed. One vessel 
would be operating primarily in the Lease Area and deep-water sections 
of the cable route (24 hour operations), with a second vessel operating 
primarily in the shallow water portion of the cable routes and 
sometimes into the deep water portion of the cable routes. Up to two 
shallow-draft vessels would work in very shallow waters (daylight only 
operations). Very shallow waters are defined as areas where only 
shallow draft vessels (<5 m) are capable of operating. Up to four 
additional vessels may be used to conduct geotechnical sampling 
activities (vibracores, seabed core penetration tests (CPTs), and 
boreholes) during the same period as the geophysical surveys but these 
activities are not expected to result in the harassment of marine 
mammals and will not be discussed further in this analysis. The 
proposed HRG survey activities are described below.

HRG Survey Activities

    For assessing potential impacts to marine mammals, the survey has 
been divided into two areas. The Deep-water Survey Area shows the Lease 
Area where wind turbine generators (WTGs) and inter-array cables will 
be installed as well as the deep-water section of the export cable 
routes. The proposed survey in this area will primarily consist of 24-
hour vessel operations, with some 12-hour per day vessel operations 
possible in the Shallow-water Survey Area which includes the rest of 
the export cable routes in shallow waters and very shallow nearshore 
waters. In the very shallow water areas, one or two shallow-draft (<5 
m) vessels will conduct nearshore surveys operating only during 
daylight hours.
    The linear distance (survey tracklines) and number of active sound 
source days, including the new proposed Narragansett Bay cable route 
corridor, for the anticipated survey activity are summarized in Table 1 
and remain unchanged from those presented in the initial notice of 
proposed IHA (86 FR 11930; March 1, 2021). The number of active sound 
source days was calculated by dividing the total survey trackline 
lengths in each area by the approximate survey distance per day 
anticipated to be achieved in each of the three zones shown in Table 1. 
The range of estimates provided for the shallow-water area result from 
assuming either daylight only (12-hours per day) survey operations or 
24-hour per day operations.

          Table 1--Activity Details for 2021 Mayflower HRG Surveys From June Through December 31, 2021
----------------------------------------------------------------------------------------------------------------
                                                                 Approximate
                                                                    survey        Approximate      Active sound
                           Location                             trackline \1\   survey distance    source days
                                                                     (km)         per day (km)
----------------------------------------------------------------------------------------------------------------
Lease Area and deep-water section of the cable route.........            7,000               80               88
Shallow-water section of the cable route.....................            3,250            30-60           55-109
Very shallow cable route.....................................            4,100               15              274
                                                              --------------------------------------------------
    Total....................................................           14,350  ...............          417-471
----------------------------------------------------------------------------------------------------------------

    Some of the sources used during the planned surveys produce sounds 
that are audible to marine mammals and, therefore, may be detected by 
marine mammals (MacGillivray et al. 2014). Multiple factors related to 
source signal characteristics (e.g., beamwidth) determine the 
likelihood of detection and, given detection, the likelihood that 
receipt of the signal would elicit a response to the degree that Level 
B harassment occurs. A geophysical survey contractor(s) has not yet 
been selected to conduct this work, so the exact equipment to be used 
is currently unknown. However, potential contractors provided 
representative sound-generating equipment that may be used during the 
survey activities. The survey activities and equipment proposed for use 
in the modified proposed IHA are identical to those presented in the 
initial notice of proposed IHA (86 FR 11930; March 1, 2021). Acoustic 
source types that could result in take of marine mammals include the 
following:
     Shallow penetration, non-impulsive, non-parametric sub-
bottom profilers (SBPs, also known as CHIRPs) are used to map the near-
surface stratigraphy (top 0 to 10 m) of sediment below seabed. A CHIRP 
system emits signals covering a frequency sweep from approximately 0.01 
to 1.9 kilohertz (kHz) over time. The frequency range can be adjusted 
to meet project variables.
     Medium penetration, impulsive sources (boomers, sparkers) 
are used to map deeper subsurface stratigraphy as needed. A boomer is a 
broad-band sound source operating in the 3.5 hertz (Hz) to 10 kHz 
frequency range. Sparkers are used to map deeper subsurface 
stratigraphy as needed. Sparkers create acoustic pulses from 50 Hz to 4 
kHz omni-directionally from the source.
    Operation of Non-impulsive, parametric SBPs; Ultra-short baseline 
(USBL) positioning systems; Multibeam echosounders (MBESs); and Side 
scan sonars (SSS) are not reasonably expected to result in take of 
marine mammals for reasons described in the initial notice of proposed 
IHA (86 FR 11930; March 1, 2021) and will not be carried forward in 
this analysis.
    Table 2 identifies the representative survey equipment that may be 
used in support of planned HRG survey activities that operate below 180 
kilohertz (kHz) (i.e., at frequencies that are audible to and therefore 
may be detected by marine mammals) and have the potential to cause 
acoustic harassment to marine mammals. The make and model of the listed 
geophysical equipment may vary depending on availability and the final 
equipment choices will vary depending upon the final survey design, 
vessel availability, and survey contractor selection. Geophysical 
surveys are expected to use several equipment types concurrently in 
order to collect multiple aspects of geophysical data along one 
transect. Selection of equipment combinations is based on specific 
survey objectives. Source levels for all equipment listed in Table 2 
came from Crocker and Fratantonio (2016).

[[Page 27397]]



      Table 2--Summary of HRG Survey Equipment Proposed for Use That Could Result in Take of Marine Mammals
----------------------------------------------------------------------------------------------------------------
                                     Operating                                                         Pulse
     Specific HRG equipment          frequency     Source level      Beamwidth     Typical pulse    repetition
                                    range (kHz)      (dB rms)        (degrees)     duration (ms)     rate (Hz)
----------------------------------------------------------------------------------------------------------------
                                                     Sparker
----------------------------------------------------------------------------------------------------------------
Geomarine Geo-Spark 400 tip 800         0.01-1.9             203             180             3.4               2
 J system.......................
Applied Acoustics Dura-Spark UHD        0.01-1.9             203             180             3.4               2
 400 tips, up to 800 J..........
----------------------------------------------------------------------------------------------------------------
                                                     Boomer
----------------------------------------------------------------------------------------------------------------
Applied Acoustics S-Boom Triple           0.01-5             205              61             0.6               3
 Plate..........................
Applied Acoustics S-Boom........          0.01-5             195              98             0.9               3
----------------------------------------------------------------------------------------------------------------
                                               Sub-Bottom Profiler
----------------------------------------------------------------------------------------------------------------
Edgetech 3100 with SB-2-16S                 2-16             179              51             9.1              10
 towfish........................
Edgetech DW-106.................             1-6             176              66            14.4              10
Teledyne Benthos Chirp III--                 2-7             199              82             5.8              10
 towfish........................
Knudson Pinger SBP..............              15             180              71               4               2
----------------------------------------------------------------------------------------------------------------

    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

    A description of the marine mammals in the area of the activities 
is found in the initial notice of proposed IHA (86 FR 11930; March 1, 
2021) and remains applicable to this modified proposed IHA.

                    Table 3--Marine Mammals Likely To Occur in the Project Area That May Be Affected by Mayflower's Proposed Activity
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         ESA/MMPA status;    Stock abundance  (CV,
             Common name                  Scientific name               Stock             strategic (Y/N)      Nmin, most recent     PBR \4\   Annual M/
                                                                                                \1\          abundance survey) \2\               SI \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Balaenidae:
    North Atlantic right whale......  Eubalaena glacialis....  Western North Atlantic.  E/D; Y              368 \3\ (0,408; 2018).       0.89       18.6
Family Balaenopteridae (rorquals):
    Humpback whale..................  Megaptera novaeangliae.  Gulf of Maine..........  -/-; Y              1,393 (0; 1,375; 2016)         22         58
    Fin whale.......................  Balaenoptera physalus..  Western North Atlantic.  E/D; Y              6,820 (0.24; 5,573;            12       2.35
                                                                                                             2016).
    Sei whale.......................  Balaenoptera borealis..  Nova Scotia............  E/D; Y              6292 (1.02; 3,098;            6.2        1.2
                                                                                                             2016).
    Minke whale.....................  Balaenoptera             Canadian East Coast....  -/-; N              21,968 (0.31; 17,002;         170       10.6
                                       acutorostrata.                                                        2016).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Physeteridae:
    Sperm whale.....................  Physeter macrocephalus.  NA.....................  E; Y                4,349 (0.28; 3,451;           3.9          0
                                                                                                             See SAR).
Family Delphinidae:
    Long-finned pilot whale.........  Globicephala melas.....  Western North Atlantic.  -/-; N              39,215 (0.3; 30,627;          306         21
                                                                                                             See SAR).
    Bottlenose dolphin..............  Tursiops spp...........  Western North Atlantic   -/-; N              62,851 (0.213; 51,914;        519         28
                                                                Offshore.                                    See SAR).
    Common dolphin..................  Delphinus delphis......  Western North Atlantic.  -/-; N              172,897 (0.21;              1,452        399
                                                                                                             145,216; 2016).
    Atlantic white-sided dolphin....  Lagenorhynchus acutus..  Western North Atlantic.  -/-; N              92,233 (0.71; 54,433;         544         26
                                                                                                             See SAR).
    Risso's dolphin.................  Grampus griseus........  Western North Atlantic.  -/-; N              35,493 (0.19; 30,289;         303       54.3
                                                                                                             See SAR).
Family Phocoenidae (porpoises):
    Harbor porpoise.................  Phocoena phocoena......  Gulf of Maine/Bay of     -/-; N              95,543 (0.31; 74,034;         851        217
                                                                Fundy.                                       2016).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Phocidae (earless seals):
    Gray seal \5\...................  Halichoerus grypus.....  Western North Atlantic.  -/-; N              27,131 (0.19; 23,158,       1,389      4,729
                                                                                                             2016).
    Harbor seal.....................  Phoca vitulina.........  Western North Atlantic.  -/-; N              75,834 (0.15; 66,884,       2,006        350
                                                                                                             2012).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds potential biological removal (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 online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region/. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable.
\3\ Pace,RM. 2021. Revisions and Further Evaluations of the Right Whale Abundance Model: Improvements for Hypothesis Testing. NOAA Technical Memorandum
  NMFS-NE-269.

[[Page 27398]]

 
\4\ Potential biological removal, 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 size (OSP). Annual M/SI, found in NMFS' stock
  assessment reports (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 values often cannot be determined precisely and is in some cases presented as a minimum
  value.
\5\ NMFS stock abundance estimate applies to U.S. population only, actual stock abundance is approximately 505,000.

    As indicated above, all 14 species (with 14 managed stocks) in 
Table 3 temporally and spatially co-occur with the proposed activity to 
the degree that take is reasonably likely to occur, and NMFS has 
proposed authorizing it.
    At the time the notice of proposed IHA published (86 FR 11930; 
March 1, 2021) 32 North Atlantic right whales have been recorded as 
confirmed dead or stranded. As of April 26, 2021, the number has 
increased to 34. Humpback whale mortalities have increased from 145 to 
149 and minke whale mortalities increased from 103 to 105 cases during 
the same time period. Additionally, the estimated abundance of North 
Atlantic right whales has been revised to 368 (Pace, 2021) since the 
initial notice of proposed IHA was published (86 FR 11930; March 1, 
2021).
    In response to the initial notice of proposed IHA (86 FR 11930; 
March 1, 2021) a group of environmental non-governmental organizations 
(ENGOs) including the Natural Resources Defense Council, Conservation 
Law Foundation, National Wildlife Federation, Defenders of Wildlife, 
Southern Environmental Law Center, Wildlife Conservation Society, 
Surfrider Foundation, Mass Audubon, Friends of the Earth, International 
Fund for Animal Welfare, NY4WHALES, WDC Whale and Dolphin Conservation, 
Marine Mammal Alliance Nantucket, Gotham Whale, All Our Energy, Seatuck 
Environmental Association, Inland Ocean Coalition, Nassau Hiking & 
Outdoor Club, and Connecticut Audubon Society; and (2) the Delaware 
Department of Resources and Environmental Control (DNREC) commented 
that NMFS had not addressed recent findings associated with aerial and 
passive acoustic monitoring of North Atlantic right whales. This 
information is described below.
    In the late fall months (e.g., October), North Atlantic right 
whales are generally thought to depart from the feeding grounds in the 
North Atlantic and move south along a migratory corridor to their 
calving grounds off Georgia and Florida. However, ongoing research 
indicates our understanding of their movement patterns remains 
incomplete (Davis et al., 2017; Oleson et al., 2020). A review of 
passive acoustic monitoring data from 2004 to 2014 throughout the 
western North Atlantic demonstrated nearly continuous year-round North 
Atlantic right whale presence across their entire habitat range (for at 
least some individuals), including in locations previously thought of 
as migratory corridors, suggesting that not all of the population 
undergoes a consistent annual migration (Davis et al., 2017). Acoustic 
monitoring data from 2004 to 2014 indicated that the number of North 
Atlantic right whale vocalizations detected in the modified proposed 
project area were relatively constant throughout the year, with the 
exception of August through October when detected vocalizations showed 
an apparent decline (Davis et al., 2017). Shifts in habitat use have 
also been observed. Cole et al. (2013) provided survey evidence that 
North Atlantic right whales were absent from the well-documented 
central Gulf of Maine winter habitat. Although present to some extent 
year round in the region south of Martha's Vineyard and Nantucket 
Islands (Oleson et al., 2020), North Atlantic right whales have 
recently been observed feeding in large numbers in this area in the 
winter (Leiter et al., 2017), which is outside of the 2016 Northeastern 
U.S. Foraging Area Critical Habitat. Observations of these transitions 
in North Atlantic right whale habitat use, variability in seasonal 
presence in identified core habitats, and utilization of habitat 
outside of previously focused survey effort prompted the formation of a 
NMFS' Expert Working Group, which identified current data collection 
efforts, data gaps, and provided recommendations for future survey and 
research efforts (Oleson et al., 2020).
    During the aerial surveys conducted in the Rhode Island/
Massachusetts and Massachusetts Wind Energy Areas (WEAs) from 2011-
2015, the highest number of North Atlantic right whale sightings (n) 
occurred in March (n=21), with sightings also occurring in December 
(n=4), January (n=7), February (n=14), and April (n=14), and no 
sightings in any other months (Kraus et al., 2016). There was not 
significant variability in sighting rate among years, indicating 
consistent annual seasonal use of the area by North Atlantic right 
whales. Despite the lack of visual detection, North Atlantic right 
whales were acoustically detected in 30 out of the 36 recorded months 
(Kraus et al., 2016). While density data from Roberts et al. (2020) 
confirm that the highest density of North Atlantic right whales in the 
project area occurs in March, it is clear that North Atlantic right 
whales are present in or near the project area throughout the year, 
particularly south of Martha's Vineyard and Nantucket Islands, which is 
thought to be an important foraging area, and that habitat use is 
changing (Leiter et al., 2017; Stone et al., 2017; Oleson et al., 
2020). The modified proposed project area is part of an important 
migratory area for North Atlantic right whales; this migratory area is 
comprised of the waters of the continental shelf offshore the East 
Coast of the United States and extends from Florida through 
Massachusetts. Aerial surveys conducted in and near the project area 
from 2011-2015 documented a total of six instances of feeding behavior 
by North Atlantic right whales (Kraus et al., 2016). Finally, the 
modified proposed project area is located within the North Atlantic 
right whale migratory corridor Biologically Important Area (BIA), which 
is applicable November 1 through December 31, 2021 and March 1, 2022 
through April 31, 2022 and extends from Florida to Massachusetts 
(LeBreque et al., 2015).
    NMFS has reviewed recent draft Stock Assessment Reports, 
information on any other relevant Unusual Mortality Events, and recent 
scientific literature, and determined that no additional new 
information affects the analysis of impacts under the initial IHA.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    A description of the potential effects of the specified activities 
on marine mammals and their habitat may be found in the documents 
supporting Mayflower's initial proposed IHA covering Lease Area OCS-A 
0521 and potential export cable routes (86 FR 11930; March 1, 2021). 
There is no new information on potential effects which would impact our 
analysis.

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

[[Page 27399]]

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 be by Level B harassment only in the form of 
disruption of behavioral patterns for individual marine mammals 
resulting from exposure to HRG sources. Based on the nature of the 
activity and the anticipated effectiveness of the mitigation measures 
(i.e., exclusion zones (EZs) and shutdown measures), discussed in 
detail below in Proposed Mitigation section, Level A harassment is 
neither anticipated nor proposed to be authorized even in the absence 
of mitigation.
    As described previously, no mortality is anticipated or proposed to 
be authorized for this activity even without the employment of 
mitigation measures. Below NMFS describes how the take is estimated.
    Generally speaking, NMFS 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. NMFS notes 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, NMFS describes the 
factors considered here in more detail and present the proposed take 
estimate.

Acoustic Thresholds

    NMFS recommends the use of 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 permanent threshold shift (PTS) of some 
degree (equated to Level A harassment).
    Level B Harassment for non-explosive sources--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). Based on what the available science indicates 
and the practical need to use a threshold based on a factor that is 
both predictable and measurable for most activities, NMFS uses a 
generalized acoustic threshold based on received level to estimate the 
onset of behavioral harassment. NMFS predicts that marine mammals are 
likely to be behaviorally harassed in a manner NMFS considers Level B 
harassment when exposed to underwater anthropogenic noise above 
received levels of 120 dB re 1 micropascal root mean square (1 [mu]Pa 
(rms) for continuous (e.g., vibratory pile-driving, drilling) and above 
160 dB re 1 [mu]Pa (rms) for non-explosive impulsive (e.g., seismic 
airguns) or intermittent (e.g., scientific sonar) sources. Mayflower's 
proposed activity includes the use of intermittent sources (geophysical 
survey equipment), and therefore use of the 160 dB re 1 [mu]Pa (rms) 
threshold is applicable.
    Level A harassment for non-explosive sources--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 non-impulsive). Mayflower's proposed activities that 
could result in take by harassment include the use of impulsive and 
non-impulsive sources.
    Predicted distances to Level A harassment isopleths, which vary 
based on marine mammal functional hearing groups were calculated. The 
updated acoustic thresholds for impulsive and non-impulsive sounds 
(such as HRG survey equipment) contained in the Technical Guidance 
(NMFS, 2018) were presented as dual metric acoustic thresholds using 
both cumulative sound exposure level (SELcum) and peak sound 
pressure level (peak SPL) metrics. As dual metrics, NMFS considers 
onset of permant threshold shift (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.
    These thresholds are provided in Table 4 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 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 4--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;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater)....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 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 [micro]Pa, and cumulative sound exposure level (LE)
  has a reference value of 1[micro]Pa\2\s. 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.


[[Page 27400]]

Ensonified Area

    Here, NMFS describes operational and environmental parameters of 
the activity that will feed into identifying the area ensonified above 
the acoustic thresholds, which include source levels and transmission 
loss coefficient.
    The proposed survey activities would entail the use of HRG 
equipment. The distance to the isopleth corresponding to the threshold 
for Level B harassment was calculated for all HRG equipment with the 
potential to result in harassment of marine mammals. NMFS has developed 
a methodology for determining distance to the 160-dB isopleth for the 
purposes of estimating take by Level B harassment resulting from 
exposure to HRG survey equipment. This methodology incorporates 
frequency and some directionality to refine estimated ensonified zones. 
Mayflower used the methods specified in the interim methodology. For 
sources that operate with different beam widths, the maximum beam width 
was used. The lowest frequency of the source was used when calculating 
the absorption coefficient. The formulas used to apply the methodology 
are described in detail in Appendix A of the IHA application.
    NMFS considers the data provided by Crocker and Fratantonio (2016) 
to represent the best available information on source levels associated 
with HRG equipment and therefore recommends that source levels provided 
by Crocker and Fratantonio (2016), when available, be incorporated in 
the method described above to estimate isopleth distances to the Level 
B harassment threshold. This was done for the sparker and boomer shown 
in Table 5. If there is no relevant information provided by Crocker and 
Fratantonio (2016) for a specific device, then manufacturers data 
should be used. This was done for the sub-bottom profiler in Table 5.

   Table 5--Estimated Distances to Level A and Level B Harassment Thresholds for the Planned Survey Equipment
----------------------------------------------------------------------------------------------------------------
                                                         Distance (m) to Level A  harassment        Distance to
                                                                    threshold \1\                     Level B
                                                    ---------------------------------------------   harassment
              Representative system(s)                                                             threshold (m)
                                                                                                 ---------------
                                                       LFC      MFC      HFC      PPW      OPW      All marine
                                                                                                      mammals
----------------------------------------------------------------------------------------------------------------
                                                     Sparker
----------------------------------------------------------------------------------------------------------------
SIG ELC 820 @750 J.................................        1       <1    \2\ 4       <1       <1             141
----------------------------------------------------------------------------------------------------------------
                                               Sub-bottom Profiler
----------------------------------------------------------------------------------------------------------------
Teledyne Benthos Chirp III.........................        2       <1       57        1       <1              66
----------------------------------------------------------------------------------------------------------------
                                                     Boomer
----------------------------------------------------------------------------------------------------------------
Applied Acoustics S-boom @700 J....................       <1       <1    \2\ 1       <1       <1              90
----------------------------------------------------------------------------------------------------------------
\1\ Distances to the Level A harassment threshold based on the larger of the dual criteria (peak SPL and SELcum)
  are shown.
\2\ Peak SPL pressure level resulted in larger isopleth than SELcum.

    Modeling of distances to isopleths corresponding to the Level A 
harassment threshold was performed for all types of HRG equipment 
proposed for use with the potential to result in harassment of marine 
mammals. Mayflower used a model developed by JASCO to calculate 
distances to Level A harassment isopleths based on both the peak SPL 
and the SELcum metric. Additional details regarding the JASCO model may 
be found in the initial proposed IHA (86 FR 11930; March 1, 2021).
    Modeled distances to isopleths corresponding to the Level A 
harassment threshold are very small (<1 m in most cases) for three of 
the four marine mammal functional hearing groups that may be impacted 
by the survey activities (i.e., low frequency and mid frequency 
cetaceans, and phocid pinnipeds). Based on the extremely small Level A 
harassment zones for these functional hearing groups, the potential for 
species within these functional hearing groups to be taken by Level A 
harassment is considered so low as to be discountable. These three 
functional hearing groups encompass all but one of the marine mammal 
species that may be impacted by the planned activities. There is one 
species (harbor porpoise) within the high frequency functional hearing 
group that may be impacted by the planned activities. However, the 
largest modeled distance to the Level A harassment threshold for the 
high frequency functional hearing group was 57 m (Table 5) for the 
Chirp III. This is likely a conservative assessment given that the 
JASCO model treats all devices as impulsive and results in gross 
overestimates for non-impulsive devices. Level A harassment would also 
be more likely to occur at close approach to the sound source or as a 
result of longer duration exposure to the sound source, and mitigation 
measures--including a 100 m exclusion zone for harbor porpoises--are 
expected to minimize the potential for close approach or longer 
duration exposure to active HRG sources. In addition, harbor porpoises 
are a notoriously shy species which is known to avoid vessels. Harbor 
porpoises would also be expected to avoid a sound source prior to that 
source reaching a level that would result in injury (Level A 
harassment). Therefore, NMFS has determined that the potential for take 
by Level A harassment of harbor porpoises or any other species is so 
low as to be discountable and does not propose authorizing take by 
Level A harassment of any marine mammals. Note that this is the same 
finding that was included in the initial notice or proposed IHA (86 FR 
11930; March 1, 2021).
    The largest distance to the 160 dB SPLrms Level B 
harassment threshold is expected to be 141 m from the sparkers. This 
distance was used as described in this section to estimate the area of 
water potentially exposed above the Level B harassment threshold by the 
planned activities.

[[Page 27401]]

    As shown in Table 1, up to 14,350 km of survey activity may occur 
from June through December 2021, including turns between lines or 
occasional testing of equipment while not collecting geophysical data. 
For the purposes of calculating take, Mayflower's HRG survey activities 
have been split into two different areas, (1) the lease area plus the 
deep-water portion of the cable routes, and (2) the shallow water 
portions of the cable routes including very shallow water sections of 
the cable routes.
    Within the Lease Area and deep-water portion of the cable route, 
the vessel will conduct surveys at a speed of approximately 3 knots 
(5.6 km/hr) during mostly 24-hr operations. Allowing for weather and 
equipment downtime, the survey vessel is expected to collect 
geophysical data over an average distance of 80 km per day. Using a 160 
dB SPLrms threshold distance of 141 m, the monthly average 
total ensonified area is estimated to be 282.8 km\2\ within the Lease 
Area and deep-water portion of the cable route.
    Along the shallow-water portion of the cable route, survey vessels 
will also conduct surveys at a speed of approximately 3 knots (5.6 km/
hr) during either daylight only or 24-hour operations. Survey 
operations in very shallow water will occur only during daylight hours. 
Allowing for weather and equipment downtime, the survey vessels are 
expected to cover an average distance of approximately 30-60 km per day 
in shallow waters and only 15 km per day in very shallow waters. 
Assuming daylight only operations and 30 km per day of surveys in 
shallow waters results in slightly larger ensonified area estimates. 
Distributing the 3,250 km of survey data to be collected in shallow 
waters and the 4,100 km to be collected in very shallow waters across 
the 7-month period of anticipated activity results in approximately 
15.5 and 39 survey days per month in shallow and very-shallow waters, 
respectively. Using a 160 dB SPLrms threshold distance of 
141 m, the total daily ensonified area in shallow waters is estimated 
to be 8.5 km\2\, and in very-shallow waters 4.3 km\2\. Combined, these 
result in an average monthly ensonified area in the combined shallow 
water survey areas of 299.5 km\2\.

Marine Mammal Occurrence

    In this section NMFS provides the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations. Note that Mayflower submitted a partial marine mammal 
monitoring report under the existing IHA (85 FR 45578; July 39, 2021) 
which included the first 90 days of survey work. A total of 415 
individual identifiable marine mammals from six species were observed 
within the predicted Level B harassment zone while an HRG source was 
active. These observations included one humpback whale, two minke 
whales, two sei whales, three bottlenose dolphins and 405 common 
dolphins. There were also two unidentified seal observations. An 
additional 24 unidentified dolphins and one unidentified whale were 
observed inside the estimated Level B harassment zone but those 
observations could not be identified to the species level. All 
mitigation and monitoring requirements were followed and Mayflower did 
not exceed authorized take limits for any species.
    Density estimates for all species except North Atlantic right whale 
within the deep and shallow portions of the survey areas were derived 
from habitat-based density modeling results reported by Roberts et al. 
(2016, 2017, 2018). Those data provide abundance estimates for species 
or species guilds within 10 km x 10 km grid cells (100 km\2\) on a 
monthly or annual basis, depending on the species. In order to select a 
representative sample of grid cells in and near the survey areas, a 10-
km wide perimeter around the lease area and an 8-km wide perimeter 
around the cable routes were created in GIS (ESRI 2017). The perimeters 
were then used to select grid cells near the survey areas containing 
the most recent monthly or annual estimates for each species in the 
Roberts et al. (2016, 2017, 2018) data. The average monthly abundance 
for each species in each survey area was calculated as the mean value 
of the grid cells within each survey area in each month and then 
converted to density (individuals/1 km\2\) by dividing by 100 km\2\ 
(Table 6, Table 7).
    The estimated monthly densities of North Atlantic right whales were 
based on updated model results from Roberts et al. (2020). These 
updated data for North Atlantic right whale are provided as densities 
(individuals/1 km\2\) within 5 km x 5 km grid cells (25 km\2\) on a 
monthly basis. The same GIS process described above was used to select 
the appropriate grid cells from each month and the monthly North 
Atlantic right whale density in each survey area was calculated as the 
mean value of the grid cells within each survey area as shown in Table 
6 and Table 7.
    The estimated monthly density of seals provided in Roberts et al. 
(2018) includes all seal species present in the region as a single 
guild. Based upon a recommendation from NMFS, Mayflower did not 
separate this guild into the individual species based on the proportion 
of sightings identified to each species within the dataset because so 
few of the total sightings used in the Roberts et al. (2018) analysis 
were actually identified to species (Table 6, Table 7).
    Marine mammal densities from Roberts et al. (2018) data in areas 
immediately adjacent to the coast and within Nantucket Sound were used 
when calculating potential takes from survey activities within 
Narragansett Bay. This is a conservative approach since there have only 
been a few reported sightings of marine mammal species, besides seals, 
within Narragansett Bay (Raposa 2009).
    For comparison purposes and to account for local variation not 
captured by the predicted densities provided by Roberts et al. (2016, 
2017, 2018, 2020), Protected Species Observers (PSOs) data from 
Mayflower's 2020 HRG surveys were analyzed to assess the 
appropriateness of the density-based take calculations. To do this, the 
total number of individual marine mammals sighted by PSOs within 150 m 
of a sound source (rounding up from the 141-m Level B harassment 
distance) from April 19 through September 19, 2020, a period of 23 
weeks, were summed by species or ``unidentified'' species group when 
sightings were not classified to the species level. As a conservative 
approach, all sightings were included in this calculation regardless of 
whether the source was operating at the time. In order to include the 
``unidentified'' individuals in the species-specific calculations, the 
number of individuals in each unidentified species group (e.g., 
unidentified whale) was then added to the sums of the known species 
within that group (e.g., humpback whale, fin whale, etc.) according to 
the proportion of individuals within that group positively identified 
to the species level. With individuals from ``unidentified'' species 
sightings proportionally distributed among the species, Mayflower then 
divided the total number of individuals of each species by the number 
of survey weeks to calculate the average number of individuals of each 
species sighted within 150 m of the sound sources per week during the 
surveys. See section 6.4 in application for additional detail.
    As described in the Dates and Duration section, Mayflower currently 
proposes for its survey activities to be concluded in December 2021. If 
the proposed survey activities extend beyond December 2021, the monthly

[[Page 27402]]

densities for the marine mammals listed below may change, potentially 
affecting take values. In that situation, Mayflower would need to 
contact NMFS to determine a path forward to ensure that they remain in 
compliance with the MMPA.

Table 6--Average Monthly Densities for Species That May Occur in the Lease Area and Along the Deep-Water Section
                               of the Cable Route During the Planned Survey Period
----------------------------------------------------------------------------------------------------------------
              Species                   Jun        Jul        Aug        Sep        Oct        Nov        Dec
----------------------------------------------------------------------------------------------------------------
                                                   Mysticetes
----------------------------------------------------------------------------------------------------------------
Fin Whale..........................     0.0025     0.0025     0.0024     0.0020     0.0013     0.0011     0.0012
Humpback Whale.....................     0.0012     0.0013     0.0009     0.0020     0.0015     0.0005     0.0006
Minke Whale........................     0.0018     0.0007     0.0005     0.0005     0.0005     0.0003     0.0004
North Atlantic Right Whale.........     0.0002     0.0000     0.0000     0.0000     0.0001     0.0005     0.0028
Sei Whale..........................     0.0002     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000
----------------------------------------------------------------------------------------------------------------
                                                   Odontocetes
----------------------------------------------------------------------------------------------------------------
Atlantic White-Sided Dolphin.......     0.0449     0.0318     0.0180     0.0183     0.0234     0.0249     0.0317
Common Bottlenose Dolphin..........     0.0267     0.0585     0.0483     0.0546     0.0459     0.0223     0.0136
Harbor Porpoise....................     0.0133     0.0088     0.0080     0.0067     0.0081     0.0267     0.0260
Pilot Whales.......................     0.0046     0.0046     0.0046     0.0046     0.0046     0.0046     0.0046
Risso's Dolphin....................     0.0001     0.0003     0.0006     0.0005     0.0002     0.0002     0.0004
Short-Beaked Common Dolphin........     0.0410     0.0432     0.0747     0.1187     0.1280     0.0903     0.1563
Sperm Whale........................     0.0001     0.0003     0.0003     0.0001     0.0001     0.0001     0.0000
----------------------------------------------------------------------------------------------------------------
                                                    Pinnipeds
----------------------------------------------------------------------------------------------------------------
Seals (Harbor and Gray)............     0.0322     0.0078     0.0041     0.0054     0.0085     0.0091     0.0345
----------------------------------------------------------------------------------------------------------------


   Table 7--Average Monthly Densities for Species That May Occur Along the Shallow-Water Section of the Cable
                                     Routes During the Planned Survey Period
----------------------------------------------------------------------------------------------------------------
              Species                   Jun        Jul        Aug        Sep        Oct        Nov        Dec
----------------------------------------------------------------------------------------------------------------
                                                   Mysticetes
----------------------------------------------------------------------------------------------------------------
Fin Whale..........................     0.0003     0.0003     0.0003     0.0003     0.0002     0.0001     0.0001
Humpback Whale.....................     0.0001     0.0001     0.0000     0.0001     0.0002     0.0001     0.0017
Minke Whale........................     0.0002     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000
North Atlantic Right Whale.........     0.0000     0.0000     0.0000     0.0000     0.0000     0.0001     0.0005
Sei Whale..........................     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000
----------------------------------------------------------------------------------------------------------------
                                                   Odontocetes
----------------------------------------------------------------------------------------------------------------
Atlantic White-Sided Dolphin.......     0.0010     0.0006     0.0005     0.0008     0.0014     0.0011     0.0006
Common Bottlenose Dolphin..........     0.2308     0.4199     0.3211     0.3077     0.1564     0.0813     0.0174
Harbor Porpoise....................     0.0048     0.0023     0.0037     0.0036     0.0003     0.0214     0.0253
Pilot Whales.......................     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000
Risso's Dolphin....................     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000
Short-Beaked Common Dolphin........     0.0003     0.0002     0.0006     0.0009     0.0008     0.0010     0.0006
Sperm Whale........................     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000
----------------------------------------------------------------------------------------------------------------
                                                    Pinnipeds
----------------------------------------------------------------------------------------------------------------
Seal (Harbor and Gray).............     0.2496     0.0281     0.0120     0.0245     0.0826     0.5456     1.3589
----------------------------------------------------------------------------------------------------------------

Take Calculation and Estimation

    Here NMFS describes how the information provided above is brought 
together to produce a quantitative take estimate.
    The potential numbers of takes by Level B harassment were 
calculated by multiplying the monthly density for each species in each 
survey area shown in Table 6 and Table 7 by the respective monthly 
ensonified area within each survey area. The results are shown in the 
``Calculated Take'' columns of Table 8. The survey area estimates were 
then summed to produce the ``Total Density-based Calculated Take'' and 
then rounded up to arrive at the number of ``Density-based Takes'' for 
each species (Table 8).
    To account for potential local variation in animal presence 
compared to the predicted densities, the average weekly number of 
individuals for each species observed within 150 m of the HRG survey 
sound sources in 2020, regardless of their operational status at the 
time were multiplied by the anticipated 32-week survey period in 2021. 
Note that the initial notice of proposed IHA (86 FR 11930; March 1, 
2021) assumed that the survey period would be 35 weeks with the same 
number of survey days (471). These results are shown in the 
``Sightings-based Takes'' column of Table 8. The larger of the take 
estimates from the density-based and sightings-based methods are shown 
in the ``Proposed Take'' column, except as noted below.

[[Page 27403]]

    Based on density and sightings data for the modified Project Area, 
Mayflower modified its take authorization request and NMFS concurred 
with its modification. Accordingly, NMFS proposes to authorize the 
following take reductions by Level B harassment as part of the modified 
proposed IHA: 37 to 33 humpback whale takes; 15 to 14 minke whale 
takes; 85 to 57 Atlantic white-sided dolphin takes; 2,153 to 1,969 
common dolphin takes; 61 to 46 harbor porpoise takes; and 989 to 718 
seal takes. The number of proposed takes by Level B harassment for 
bottlenose dolphins has been increased from 483 to 536.
    The differences in requested take for four species (Atlantic white-
sided dolphin, common bottlenose dolphin, harbor porpoise, and seals) 
resulted from a combination of different monthly densities as well as a 
different monthly ensonified area being applied to those densities. The 
same calculations were performed for all species, so the relative 
changes in the requested take for these species was driven by the 
amount of change in monthly densities for each species. The densities 
changed between applications for two reasons, (1) the survey area 
location was changed to include the alternative cable route and (2) the 
months in which the activity will occur were shifted later in the year, 
from April-November to June-December. The various combinations of 
changes to these factors resulted in different relative changes to the 
requested takes for these four species.
    For the other three species (i.e., humpback whale, minke whale, 
common dolphin) take calculated based on Roberts et al. densities was 
considerably lower than observed numbers of animals during the 2020 
surveys. Therefore, the numbers of observations per week were 
considered more representative of the area densities. For humpback 
whale, the requested take in the original proposed IHA was based on the 
average weekly sightings rate from 2020 PSO observations (1.04 humpback 
whales/week). The reduction in the proposed take is a result of the 
shortened overall length of the activity from 35 weeks to 32 weeks. For 
minke whale, the average weekly sightings rate from 2020 PSO 
observations (0.43 minke whales/week) reduced proposed take due to 
shortened overall length of the activity (from 35 weeks to 32 weeks). 
The same reduction in proposed take of common dolphin was similarly 
based on the average weekly sightings rate from 2020 PSO observations 
(61.52 common dolphins/week) and the decreased overall length of the 
activity. The reduction in the requested take is a result of the 
shortened overall length of the activity (from 35 weeks to 32 weeks).
    Using the best available density data (Roberts et al. 2016, 2017, 
2018, 2020), Mayflower requested and NMFS proposes to authorize 57 
takes of white-sided dolphin, 536 takes of bottlenose dolphin and 46 
harbor porpoise takes by Level B harassment. For six species, humpback 
whale, North Atlantic right whale, sei whale, pilot whales, Risso's 
dolphin, and sperm whale the proposed take column reflects a rounding 
up of three times the mean group size calculated from survey data in 
this region (Kraus et al. 2016; Palka et al. 2017). Three times the 
group size was used rather than a single group size to account for more 
than one chance encounter with these species during the surveys.
    NFMS concurred with this assessment and, therefore, proposes the 
authorization of 9 North Atlantic right whale, 6 fin whale, 6 sei 
whale, 27 pilot whale, 18 Risso's dolphin, and 6 sperm whale takes by 
Level B harassment. The proposed take authorization numbers for these 
species remains unchanged from the original proposed IHA.
    The proposed number of takes by Level B harassment as a percentage 
of the ``best available'' abundance estimates provided in the most 
recent NMFS draft Stock Assessment Reports (Hayes et al. 2020) are also 
provided in Table 8. For the seal guild, the estimated abundance for 
both gray and harbor seals was summed in Table 8. Mayflower requested 
and NMFS proposes to authorize 718 incidental takes of harbor and gray 
seal by Level B harassment.
    Bottlenose dolphins encountered in the survey area would likely 
belong to the Western North Atlantic Offshore Stock (Hayes et al. 
2020). However, it is possible that a few animals encountered during 
the surveys could be from the North Atlantic Northern Migratory Coastal 
Stock, but they generally do not range farther north than New Jersey. 
Also, based on the distributions described in Hayes et al. (2020), 
pilot whale sightings in the survey area would most likely be long-
finned pilot whales, although short-finned pilot whales could be 
encountered in the survey area during the summer months.
    For North Atlantic right whales, the implementation of a 500 m 
exclusion zone means that the likelihood of an exposure to received 
sound levels greater than 160 dB SPLrms is very low. In 
addition, most of the survey activity will take place during the time 
of year when North Atlantic right whales are unlikely to be present in 
this region. Nonetheless, it is possible that North Atlantic right 
whales could occur within 500 m of the vessel without first being 
detected PSO, so Mayflower requested and NMFS proposes to authorize 
take consistent with other species (i.e. three times average group 
size).

                                    Table 8--Number of Level B Takes Proposed and Percentages of Each Stock Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                       Total
                                                           Lease area +    Shallow    density-   Density   Sightings   Proposed               Percent of
                                                            deep water      water      based      based      based      takes     Abundance     stock
                                                               cable        cable      takes      takes      takes                            abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Mysticetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fin Whale...............................................             3.7        0.5        4.1          5          1          6       3,006          0.2
Humpback Whale..........................................             2.2        0.7        2.9          3         33         33       1,396          2.4
Minke Whale.............................................             1.3        0.1        1.5          2         14         14       2,591          0.5
North Atlantic Right Whale..............................             1.0        0.2        1.2          2          0          9         368          2.4
Sei Whale...............................................             0.1        0.0        0.1          1          0          6          28         21.4
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Odontocetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Atlantic White-Sided Dolphin............................            54.6        1.8       56.4         57          0         57      31,912          0.2
Common Bottlenose Dolphin...............................            76.3      459.6      536.0        536         59        536      62,851          0.9
Harbor Porpoise.........................................            27.6       18.4       46.0         46          0         46      75,079          0.1
Pilot Whales............................................             9.2        0.0        9.2         10         17         27      68,139          0.0
Risso's Dolphin.........................................             0.7        0.0        0.7          1          0         18      35,493          0.1
Short-Beaked Common Dolphin.............................           184.5        1.3      185.8        186      1,969      1,969      80,227          2.5

[[Page 27404]]

 
Sperm Whale.............................................             0.3        0.0        0.3          1          0          6       4,349          0.1
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Pinnipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Seals (Harbor and Gray).................................            28.7      689.2      718.0        718        141        718     102,965          0.7
--------------------------------------------------------------------------------------------------------------------------------------------------------

Proposed Mitigation

    The mitigation, monitoring, and reporting measures described here 
are identical to those included in the Federal Register notice 
announcing the initial proposed IHA and the discussion of the least 
practicable adverse impact included in that document remains accurate 
(86 FR 11930; 2021).

Marine Mammal Exclusion Zones and Harassment Zones

    NMFS proposes the following mitigation measures be implemented 
during Mayflower's proposed marine site characterization surveys.
    Marine mammal EZs would be established around the HRG survey 
equipment and monitored by PSOs during HRG surveys as follows:
     A 500-m EZ would be required for North Atlantic right 
whales during use of all acoustic sources; and
     100 m EZ for all marine mammals, with certain exceptions 
specified below, during operation of impulsive acoustic sources (boomer 
and/or sparker).
    If a marine mammal is detected approaching or entering the EZs 
during the HRG survey, the vessel operator would adhere to the shutdown 
procedures described below to minimize noise impacts on the animals. 
These stated requirements will be included in the site-specific 
training to be provided to the survey team.

Pre-Clearance of the Exclusion Zones

    Mayflower would implement a 30-minute pre-clearance period of the 
EZs zones prior to the initiation of ramp-up of HRG equipment. During 
this period, the EZs will be monitored by the PSOs, using the 
appropriate visual technology. Ramp-up may not be initiated if any 
marine mammal(s) is within its respective EZ. If a marine mammal is 
observed within an EZ during the pre-clearance period, ramp-up may not 
begin until the animal(s) has been observed exiting its respective EZ 
or until an additional time period has elapsed with no further sighting 
(i.e., 15 minutes for small odontocetes and seals, and 30 minutes for 
all other species).

Ramp-Up of Survey Equipment

    When technically feasible, a ramp-up procedure would be used for 
HRG survey equipment capable of adjusting energy levels at the start or 
restart of survey activities. The ramp-up procedure would be used at 
the beginning of HRG survey activities in order to provide additional 
protection to marine mammals near the Project Area by allowing them to 
vacate the area prior to the commencement of survey equipment operation 
at full power.
    A ramp-up would begin with the powering up of the smallest acoustic 
HRG equipment at its lowest practical power output appropriate for the 
survey. When technically feasible, the power would then be gradually 
turned up and other acoustic sources would be added.
    Ramp-up activities will be delayed if a marine mammal(s) enters its 
respective EZ. Ramp-up will continue if the animal has been observed 
exiting its respective EZ or until an additional time period has 
elapsed with no further sighting (i.e., 15 minutes for small 
odontocetes and seals and 30 minutes for all other species).
    Activation of survey equipment through ramp-up procedures may not 
occur when visual observation of the pre-clearance zone is not expected 
to be effective (i.e., during inclement conditions such as heavy rain 
or fog).

Shutdown Procedures

    An immediate shutdown of the impulsive HRG survey equipment would 
be required if a marine mammal is sighted entering or within its 
respective EZ. The vessel operator must comply immediately with any 
call for shutdown by the Lead PSO. Any disagreement between the Lead 
PSO and vessel operator should be discussed only after shutdown has 
occurred. Subsequent restart of the survey equipment can be initiated 
if the animal has been observed exiting its respective EZ or until an 
additional time period has elapsed (i.e., 30 minutes for all other 
species).
    If a species for which authorization has not been granted, or, a 
species for which authorization has been granted but the authorized 
number of takes have been met, approaches or is observed within the 
Level B harassment zone (48 m, non-impulsive; 141 m impulsive), 
shutdown would occur.
    If the acoustic source is shut down for reasons other than 
mitigation (e.g., mechanical difficulty) for less than 30 minutes, it 
may be activated again without ramp-up if PSOs have maintained constant 
observation and no detections of any marine mammal have occurred within 
the respective EZ. If the acoustic source is shut down for a period 
longer than 30 minutes and PSOs have maintained constant observation, 
then pre-clearance and ramp-up procedures will be initiated as 
described in the previous section.
    The shutdown requirement would be waived for small delphinids of 
the following genera: Delphinus, Lagenorhynchus, Stenella, and Tursiops 
and seals. Specifically, if a delphinid from the specified genera or a 
pinniped is visually detected approaching the vessel (i.e., to bow 
ride) or towed equipment, shutdown is not required. Furthermore, if 
there is uncertainty regarding identification of a marine mammal 
species (i.e., whether the observed marine mammal(s) belongs to one of 
the delphinid genera for which shutdown is waived), PSOs must use best 
professional judgement in making the decision to call for a shutdown. 
Additionally, shutdown is required if a delphinid or pinniped detected 
in the EZ and belongs to a genus other than those specified.

Vessel Strike Avoidance

    Mayflower will ensure that vessel operators and crew maintain a 
vigilant watch for cetaceans and pinnipeds and slow down or stop their 
vessels to avoid striking these species. Survey vessel crew members 
responsible for navigation duties will receive site-specific training 
on marine mammals sighting/reporting and vessel strike avoidance 
measures. Vessel strike avoidance measures would include the following, 
except under circumstances when complying with these requirements would 
put the safety of the vessel or crew at risk:

[[Page 27405]]

     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 protected species. A visual observer aboard the vessel must monitor 
a vessel strike avoidance zone based on the appropriate separation 
distance 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 protected species from other phenomena and (2) broadly to 
identify a marine mammal as a North American right whale, other whale 
(defined in this context as sperm whales or baleen whales other than 
right whales), or other marine mammal.
     All vessels, regardless of size, must observe a 10-knot 
speed restriction in specific areas designated by NMFS for the 
protection of North Atlantic right whales from vessel strikes including 
seasonal management areas (SMAs) and dynamic management areas (DMAs) 
when in effect;
     All vessels greater than or equal to 19.8 m in overall 
length operating from November 1 through April 30 will operate at 
speeds of 10 knots or less while transiting to and from Project Area;
     All vessels must reduce their speed to 10 knots or less 
when mother/calf pairs, pods, or large assemblages of cetaceans are 
observed near a vessel.
     All vessels must maintain a minimum separation distance of 
500 m from North Atlantic 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.
     All vessels must maintain a minimum separation distance of 
100 m from sperm whales and all other baleen whales.
     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).
     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.
     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.
     Members of the monitoring team will consult NMFS North 
Atlantic right whale reporting system and Whale Alert, as able, for the 
presence of North Atlantic right whales throughout survey operations, 
and for the establishment of a DMA. If NMFS should establish a DMA in 
the Lease Areas during the survey, the vessels will abide by speed 
restrictions in the DMA.
    Project-specific training will be conducted for all vessel crew 
prior to the start of a survey and during any changes in crew such that 
all survey personnel are fully aware and understand the mitigation, 
monitoring, and reporting requirements. Prior to implementation with 
vessel crews, the training program will be provided to NMFS for review 
and approval. Confirmation of the training and understanding of the 
requirements will be documented on a training course log sheet. Signing 
the log sheet will certify that the crew member understands and will 
comply with the necessary requirements throughout the survey 
activities.
    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, NMFS has preliminarily 
determined that the proposed mitigation measures provide the means of 
effecting the least practicable impact on marine mammal species or 
stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance.

Proposed Monitoring and Reporting

    The monitoring, and reporting measures described here are identical 
to those included in the Federal Register notice announcing the initial 
proposed IHA (86 FR 11930; March 1, 2021).
    Visual monitoring will be performed by qualified, NMFS-approved 
PSOs, the resumes of whom will be provided to NMFS for review and 
approval prior to the start of survey activities. Mayflower would 
employ independent, dedicated, trained PSOs, meaning that the PSOs must 
(1) be employed by a third-party observer provider, (2) have no tasks 
other than to conduct observational effort, collect data, and 
communicate with and instruct relevant vessel crew with regard to the 
presence of marine mammals and mitigation requirements (including brief 
alerts regarding maritime hazards), and (3) have successfully completed 
an approved PSO training course appropriate for their designated task. 
On a case-by-case basis, non-independent observers may be approved by 
NMFS for limited, specific duties in support of approved, independent 
PSOs on smaller vessels with limited crew capacity operating in 
nearshore waters.
    The PSOs will be responsible for monitoring the waters surrounding 
each survey vessel to the farthest extent permitted by sighting 
conditions, including EZs, during all HRG survey operations. PSOs will 
visually monitor and identify marine mammals, including those 
approaching or entering the established EZs during survey activities. 
It will be the responsibility of the Lead PSO on duty to communicate 
the presence of marine mammals as well as to communicate the action(s) 
that are necessary to ensure mitigation and monitoring requirements are 
implemented as appropriate.
    During all HRG survey operations (e.g., any day on which use of an 
HRG source is planned to occur), a minimum of one PSO must be on duty 
during daylight operations on each survey vessel, conducting visual 
observations at all times on all active survey vessels during daylight 
hours (i.e., from 30 minutes prior to sunrise through 30 minutes 
following sunset). Two PSOs will be on watch during nighttime 
operations. The PSO(s) would ensure 360[deg] visual coverage around the 
vessel from the most appropriate observation posts and would conduct 
visual observations using binoculars and/or night vision goggles and 
the naked eye while free from distractions and in a consistent, 
systematic, and diligent manner. PSOs may be on watch for a maximum of 
four consecutive hours followed by a break of at least two hours 
between watches and may conduct a maximum of 12 hours of observation 
per 24-hour period. In cases where multiple vessels are surveying 
concurrently, any observations of marine mammals would be communicated 
to PSOs on all nearby survey vessels.
    Vessels conducting HRG survey activities in very-shallow waters 
using shallow-draft vessels are very limited in the number of personnel 
that can be onboard. In such cases, one visual PSO will be onboard and 
the vessel captain (or crew member on watch) will

[[Page 27406]]

conduct observations when the PSO is on required breaks. All vessel 
crew conducting PSO watches will receive training in monitoring and 
mitigation requirements and species identification necessary to 
reliably carry out the mitigation requirements. Given the small size of 
these vessels, the PSO would effectively remain available to confirm 
sightings and any related mitigation measures while on break.
    PSOs must be equipped with binoculars and have the ability to 
estimate distance and bearing to detect marine mammals, particularly in 
proximity toEZs. Reticulated binoculars must also be available to PSOs 
for use as appropriate based on conditions and visibility to support 
the sighting and monitoring of marine mammals. During nighttime 
operations, night-vision goggles with thermal clip-ons and infrared 
technology would be used. Position data would be recorded using hand-
held or vessel GPS units for each sighting.
    During good conditions (e.g., daylight hours; Beaufort sea state 
(BSS) 3 or less), to the maximum extent practicable, PSOs would also 
conduct observations when the acoustic source is not operating for 
comparison of sighting rates and behavior with and without use of the 
active acoustic sources. Any observations of marine mammals by crew 
members aboard any vessel associated with the survey would be relayed 
to the PSO team.
    Data on all PSO observations would be recorded based on standard 
PSO collection requirements. This would include dates, times, and 
locations of survey operations; dates and times of observations, 
location and weather; details of marine mammal sightings (e.g., 
species, numbers, behavior); and details of any observed marine mammal 
behavior that occurs (e.g., noted behavioral disturbances).

Proposed Reporting Measures

    Within 90 days after completion of survey activities or expiration 
of this IHA, whichever comes sooner, a final technical report will be 
provided to NMFS that fully documents the methods and monitoring 
protocols, summarizes the data recorded during monitoring, summarizes 
the number of marine mammals observed during survey activities (by 
species, when known), summarizes the mitigation actions taken during 
surveys (including what type of mitigation and the species and number 
of animals that prompted the mitigation action, when known), and 
provides an interpretation of the results and effectiveness of all 
mitigation and monitoring. Any recommendations made by NMFS must be 
addressed in the final report prior to acceptance by NMFS. All draft 
and final marine mammal and acoustic monitoring reports must be 
submitted to [email protected] and 
[email protected]. The report must contain, at minimum, the 
following:
     PSO names and affiliations
     Dates of departures and returns to port with port name
     Dates and times (Greenwich Mean Time) of survey effort and 
times corresponding with PSO effort
     Vessel location (latitude/longitude) when survey effort 
begins and ends; 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 change 
significantly), including wind speed and direction, Beaufort sea state, 
Beaufort wind force, swell height, weather conditions, cloud cover, sun 
glare, and overall visibility to the horizon
     Factors that may be contributing to impaired observations 
during each PSO shift change or as needed as environmental conditions 
change (e.g., vessel traffic, equipment malfunctions)
     Survey activity information, such as type of survey 
equipment in operation, acoustic source power output while in 
operation, and any other notes of significance (i.e., pre-clearance 
survey, ramp-up, shutdown, end of operations, etc.)
    If a marine mammal is sighted, the following information should be 
recorded:
     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); also note 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, 
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 and/or closest distance 
from the center point of the acoustic source;
     Platform activity at time of sighting (e.g., deploying, 
recovering, testing, data acquisition, other);
     Description of any actions implemented in response to the 
sighting (e.g., delays, shutdown, ramp-up, speed or course alteration, 
etc.) and time and location of the action.
    If a North Atlantic right whale is observed at any time by PSOs or 
personnel on any project vessels, during surveys or during vessel 
transit, Mayflower must immediately report sighting information to the 
NMFS North Atlantic Right Whale Sighting Advisory System: (866) 755-
6622. North Atlantic right whale sightings in any location may also be 
reported to the U.S. Coast Guard via channel 16.
    In the event that Mayflower personnel discover an injured or dead 
marine mammal, Mayflower would report the incident to the NMFS Office 
of Protected Resources (OPR) and the NMFS New England/Mid-Atlantic 
Regional Stranding Coordinator as soon as feasible ((866) 755-6622). 
The report would 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.
    In the unanticipated event of a ship strike of a marine mammal by 
any vessel involved in the activities covered by the IHA, Mayflower 
would report the incident to the NMFS OPR 
([email protected]) and the NMFS New England/Mid-

[[Page 27407]]

Atlantic Stranding Coordinator ((866) 755-6622) as soon as feasible. 
The report would include the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Species identification (if known) or description of the 
animal(s) involved;
     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 measures 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;
     Estimated size and length of animal that was struck;
     Description of the behavior of the marine mammal 
immediately preceding and following the strike;
     If available, description of the presence and behavior of 
any other marine mammals 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).

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., population-
level effects). An estimate of the number of takes alone is not enough 
information on which to base an impact determination. In addition to 
considering estimates of the number of marine mammals that might be 
``taken'' 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. NMFS 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 the species listed 
in Table 8 given that NMFS expects the anticipated effects of the 
proposed survey to be similar in nature. Where there are meaningful 
differences between species or stocks--as in the case of the North 
Atlantic right whale--they are included as separate subsections below.
    NMFS does not anticipate that serious injury or mortality would 
occur as a result from HRG surveys, even in the absence of mitigation, 
and no serious injury or mortality is proposed to be authorized. As 
discussed in the Potential Effects of Specified Activity on Marine 
Mammals and their Habitat section in the initial notice of proposed IHA 
(86 FR 11930; March 1, 2021), non-auditory physical effects and vessel 
strike are not expected to occur. NMFS expects that all potential takes 
would be in the form of short-term Level B harassment behavioral 
harassment in the form of temporary avoidance of the area or decreased 
foraging (if such activity was occurring), reactions that are 
considered to be of low severity and with no lasting biological 
consequences (e.g., Southall et al., 2007). Even repeated Level B 
harassment of some small subset of an overall stock is unlikely to 
result in any significant realized decrease in viability for the 
affected individuals, and thus would not result in any adverse impact 
to the stock as a whole. As described above, Level A harassment is not 
expected to occur given the nature of the operations, the estimated 
size of the Level A harassment zones, and the required shutdown zones 
for certain activities--and is not proposed to be authorized. The 
potential effects associated with the addition of the new export cable 
route extending through Narragansett Bay are similar to those described 
in the initial notice of proposed IHA (86 FR 11930; March 1, 2021).
    In addition to being temporary, the maximum expected harassment 
zone for the modified proposed IHA is identical to that in the initial 
proposed IHA with a distance of 141 m per vessel. Therefore, the 
ensonified area surrounding each vessel is also identical, and 
relatively small, compared to the overall distribution of the animals 
in the area and their use of the habitat. Feeding behavior is not 
likely to be significantly impacted as prey species are mobile and are 
broadly distributed throughout the modified Project Area; 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. 
Similar to the initial proposed IHA, given the temporary nature of the 
disturbance and 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 long-term 
consequences for individual marine mammals or their populations in the 
modified proposed IHA.
    Furthermore, the modified proposed Project Area is located 
approximately 50 miles west of feeding BIAs for North Atlantic right 
whales (February-April) and sei whales (May-November) and approximately 
40 west of feeding BIAs for humpback whales (March-December) and fin 
whales (March-October). These were discussed in the previous IHA (85 FR 
45578; July 29, 2020) issued for this area. Additionally, the new 
proposed Narragansett Bay cable route corridor is located just to the 
north of the another fin whale BIA (March-October) located south of 
Martha's Vineyard. Even if whales are feeding outside of the identified 
feeding BIAs, they are extensive and sufficiently large (705 km\2\ and 
3,149 km\2\ for North Atlantic right whales; 47,701 km\2\ for humpback 
whales; 2,933 km\2\ for fin whales; and 56,609 km\2\ for sei whales), 
and the acoustic footprint of the proposed survey is sufficiently 
small, such that feeding opportunities for these whales would not be 
reduced appreciably. Therefore, under the modified proposed IHA, NMFS 
does not expect impacts to whales within feeding BIAs to affect the 
fitness of any large whales. Furthermore, NMFS does not anticipate 
impacts from the modified proposed survey that would impact annual 
rates of recruitment or survival and any takes that occur would not 
result in population level impacts.
    There are no rookeries, mating or calving grounds known to be 
biologically important to marine mammals within the modified proposed 
Project Area. Furthermore, there is no designated critical habitat for 
any ESA-listed marine mammals in the proposed Project Area.

[[Page 27408]]

North Atlantic Right Whales

    The status of the North Atlantic right whale population is of 
heightened concern and, therefore, merits additional analysis. As noted 
previously, elevated North Atlantic right whale mortalities began in 
June 2017 and there is an active UME. Overall, preliminary findings 
support human interactions, specifically vessel strikes and 
entanglements, as the cause of death for the majority of North Atlantic 
right whales. In addition to the right whale feeding BIA located west 
of the modified proposed Project Area noted above, the modified 
proposed Project Area overlaps a migratory corridor BIA for North 
Atlantic right whales (effective March-April and November-December) 
that extends from Massachusetts to Florida (LeBrecque et al., 2015). 
Off the coast of Massachusetts, this migratory BIA extends from the 
coast to beyond the shelf break. Due to the fact that that the proposed 
survey activities are temporary and the spatial extent of sound 
produced by the survey would be very small relative to the spatial 
extent of the available migratory habitat in the BIA, right whale 
migration is not expected to be impacted by the proposed survey. Given 
the relatively small size of the ensonified area, it is unlikely that 
prey availability would be adversely affected by HRG survey operations. 
Required vessel strike avoidance measures will also decrease risk of 
ship strike during migration; no ship strike is expected to occur 
during Mayflower's proposed activities. Additionally, only very limited 
take by Level B harassment of North Atlantic right whales has been 
requested by Mayflower and is being proposed by NMFS as HRG survey 
operations are required to maintain a 500 m EZ and shutdown if a North 
Atlantic right whale is sighted at or within the EZ. The 500 m shutdown 
zone for North Atlantic right whales is conservative, considering the 
Level B harassment isopleth for the most impactful acoustic source 
(i.e., GeoMarine Geo-Source 400 tip sparker) is estimated to be 141 m, 
and thereby minimizes the potential for behavioral harassment of this 
species. As noted previously, Level A harassment is not expected due to 
the small PTS zones associated with HRG equipment types proposed for 
use.
    As described previously, North Atlantic right whale presence is 
increasingly variable in identified core habitats, including the 
recently identified foraging area south of Martha's Vineyard and 
Nantucket islands where both visual and acoustic detections of North 
Atlantic right whales indicate a nearly year-round presence (Oleson et 
al., 2020), although seasonal trends are still prominent (Hayes et al., 
2020). However, prey for North Atlantic right whales are mobile and 
broadly distributed throughout the project area; therefore, North 
Atlantic right whales are expected to be able to resume foraging once 
they have moved away from any areas with disturbing levels of 
underwater noise. In addition, there are no North Atlantic right whale 
mating or calving areas within the proposed project area.
    Given the information above, NMFS does not anticipate North 
Atlantic right whales takes that would result from Mayflower's proposed 
activities would impact the reproduction or survival of any individual 
North Atlantic right whales, much less annual rates of recruitment or 
survival. Thus, any takes that occur under the modified proposed IHA 
would not result in population level impacts for the species.

Other Marine Mammal Species With Active UMEs

    As noted in the previous IHA (85 FR 45578; July 29, 2020) there are 
several active UMEs occurring in the vicinity of Mayflower's modified 
proposed Project Area. Elevated humpback whale mortalities have 
occurred along the Atlantic coast from Maine through Florida since 
January 2016. Of the cases examined, approximately half had evidence of 
human interaction (ship strike or entanglement). The UME does not yet 
provide cause for concern regarding population-level impacts. Despite 
the UME, the relevant population of humpback whales (the West Indies 
breeding population, or distinct population segment (DPS)) remains 
stable at approximately 12,000 individuals.
    Beginning in January 2017, elevated minke whale strandings have 
occurred along the Atlantic coast from Maine through South Carolina, 
with highest numbers in Massachusetts, Maine, and New York. This event 
does not provide cause for concern regarding population level impacts, 
as the population abundance is greater than 20,000 whales.
    Elevated numbers of harbor seal and gray seal mortalities were 
first observed in July 2018 and have occurred across Maine, New 
Hampshire, and Massachusetts. Based on tests conducted so far, the main 
pathogen found in the seals is phocine distemper virus, although 
additional testing to identify other factors that may be involved in 
this UME are underway. The UME does not yet provide cause for concern 
regarding population-level impacts to any of these stocks. For harbor 
seals, the population abundance is over 75,000 and annual M/SI (350) is 
well below PBR (2,006) (Hayes et al., 2020). The population abundance 
for gray seals in the United States is over 27,000, with an estimated 
abundance, including seals in Canada, of approximately 505,000. In 
addition, the abundance of gray seals is likely increasing in the U.S. 
Atlantic Exclusive Economic Zone as well as in Canada (Hayes et al., 
2020).
    The required mitigation measures are expected to reduce the number 
and/or severity of proposed takes for all species listed in Table 8, 
including those with active UME's to the level of least practicable 
adverse impact. In particular they would provide animals the 
opportunity to move away from the sound source throughout the modified 
proposed Project Area before HRG survey equipment reaches full energy, 
thus preventing them from being exposed to sound levels that have the 
potential to cause injury (Level A harassment) or more severe Level B 
harassment. No Level A harassment is anticipated, even in the absence 
of mitigation measures, or proposed for authorization.
    NMFS expects that takes would be in the form of short-term Level B 
harassment behavioral harassment by way of brief startling reactions 
and/or temporary vacating of the area, or decreased foraging (if such 
activity was occurring)--reactions that (at the scale and intensity 
anticipated here) are considered to be of low severity, with no lasting 
biological consequences. Since both the sources and marine mammals are 
mobile, animals would only be exposed briefly to a small ensonified 
area that might result in take. Additionally, required mitigation 
measures would further reduce exposure to sound that could result in 
more severe behavioral harassment.
    The total duration of the modified proposed HRG survey activities 
is 471 survey days and the total trackline distance is 14,350 km which 
are identical to the values presented in the initial proposed IHA (86 
FR 11930; March 1, 2021) and any effects or impacts are expected to be 
similar. Note that proposed takes in the modified proposed IHA have 
been reduced for 6 species from the initial proposed IHA (i.e., 
humpback whale, minke whale, Atlantic white-sided dolphin, common 
dolphin, harbor porpoise and seal) while proposed take has only 
increased for one species (i.e., bottlenose dolphin).
    In summary and as described above, the following factors primarily 
support our preliminary determination that the

[[Page 27409]]

impacts resulting from this activity are not expected to adversely 
affect the species or stock through effects on annual rates of 
recruitment or survival:
     No mortality or serious injury is anticipated or proposed 
for authorization;
     No Level A harassment (PTS) is anticipated, even in the 
absence of mitigation measures, or proposed for authorization;
     Foraging success is not likely to be significantly 
impacted as effects on species that serve as prey species for marine 
mammals from the survey are expected to be minimal;
     Due to the relatively small footprint of the survey 
activities in relation to the size of feeding BIAs for North Atlantic 
right, humpback, fin, and sei whales, the survey activities would not 
affect foraging success of these whale species;
     The availability of alternate areas of similar habitat 
value for marine mammals to temporarily vacate the Project Area during 
the planned survey to avoid exposure to sounds from the activity;
     Take is anticipated to be limited to Level B behavioral 
harassment consisting of brief startling reactions and/or temporary 
avoidance of the Project Area;
     While the Project Area is within areas noted as a 
migratory BIA for North Atlantic right whales, the activities would 
occur in such a comparatively small area such that any avoidance of the 
Project Area due to activities would not affect migration. In addition, 
mitigation measures to shutdown at 500 m to minimize potential for 
Level B behavioral harassment would limit any take of the species;
     While the foraging areas south of Martha's Vineyard and 
Nantucket overlap with the Project Area, prey for North Atlantic right 
whales are mobile and broadly distributed. Therefore, North Atlantic 
right whales are expected to be able to resume foraging once they have 
moved away from any areas with disturbing noise levels, which would be 
temporary in nature;
     The proposed mitigation measures, including visual 
monitoring and shutdowns, are expected to minimize potential impacts to 
marine mammals; and
     While UMEs are in effect for some species, the take from 
Mayflower's activities is not expected to impact the reproduction or 
survival of any individuals of any species, and therefore, is not 
expected to impact annual rates of recruitment or survival either alone 
or in combination with the effects of the UMEs.
    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 monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take from the modified 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.
    NMFS proposes to authorize incidental take of 14 marine mammal 
species. The total amount of takes proposed for authorization is less 
than 3 percent for all species and stocks authorized for take except 
for sei whales (less than 22 percent), which NMFS preliminarily finds 
are small numbers of marine mammals relative to the estimated overall 
population abundances for those stocks. See Table 8. 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

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

Endangered Species Act

    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 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, in this case with the NMFS Greater Atlantic 
Regional Fisheries Office (GARFO), whenever NMFS proposes to authorize 
take for endangered or threatened species.
    The NMFS OPR is proposing to authorize the incidental take of four 
species of marine mammals listed under the ESA: The North Atlantic 
right, fin, sei, and sperm whale. The OPR has requested initiation of 
Section 7 consultation with NMFS GARFO for the issuance of this IHA. 
NMFS will conclude the ESA section 7 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 Mayflower for conducting marine site characterization 
surveys offshore of Massachusetts in the area of the Commercial Lease 
of Submerged Lands for Renewable Energy Development on the Outer 
Continental Shelf (OCS-A 0521) and along a potential submarine cable 
routes to landfall at Falmouth, Massachusetts and Narragansett Bay for 
a period of one year from the date of issuance, provided the previously 
mentioned mitigation, monitoring, and reporting requirements are 
incorporated. A draft of the modified proposed IHA can be found at 
https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.

Request for Public Comments

    NMFS requests comment on our analyses, the proposed authorization, 
and any other aspect of this notice of a modified proposed IHA for the 
proposed marine site characterization surveys. NMFS also requests at 
this time comment on the potential Renewal of this modified 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

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following notice to the public providing an additional 15 days for 
public comments when (1) up to another year of identical or nearly 
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).
    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.

Catherine Marzin,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2021-10551 Filed 5-19-21; 8:45 am]
BILLING CODE 3510-22-P