Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Site Characterization Surveys off the Coast of Massachusetts, 11930-11947 [2021-04161]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 86, Number 38 (Monday, March 1, 2021)]
[Notices]
[Pages 11930-11947]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-04161]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XA869]


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; proposed incidental harassment authorization; request 
for comments on 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 a 
potential submarine cable route to landfall at Falmouth, Massachusetts. 
Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting 
comments on its proposal to issue an incidental harassment 
authorization (IHA) to incidentally take marine mammals during the 
specified activities. NMFS is also requesting comments on a possible 
one-year renewal that could be issued under certain circumstances and 
if all requirements are met, as described in Request for Public 
Comments at the end of this notice. NMFS will consider public comments 
prior to making any final decision on the issuance of the requested 
MMPA authorizations and agency responses will be summarized in the 
final notice of our decision.

DATES: Comments must be received by March 31, 2021.

ADDRESSES: Comments should be addressed to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National

[[Page 11931]]

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 Lease Area OCS-A 0521and a submarine export cable 
route connecting the Lease Area to landfall 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 is for take of a small number of 14 species of 
marine mammals by Level B harassment only. Neither Mayflower nor NMFS 
expects serious injury or mortality to result from this activity and, 
therefore, an IHA is appropriate.
    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 is effective from July 23, 2020 through July 
22, 2021. However, the surveys began on July 23, 2020 and ended on 
October 23, 2020. Mayflower submitted a marine mammal monitoring report 
and complied with all the requirements (e.g., mitigation, monitoring, 
and reporting) of the previous IHA. Information regarding their 
monitoring results may be found in the Estimated Take section.

Description of Proposed Activity

Overview

    Mayflower proposes to conduct marine site characterization surveys, 
including high-resolution geophysical (HRG) and geotechnical surveys, 
in the Lease Area and along a potential submarine cable route to 
landfall at Falmouth, Massachusetts.
    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 the Lease Area and along 
the proposed export cable route corridor.
    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 HRG survey activities would be approximately 
471 survey days. Each day that a survey vessel is operating counts as a 
single survey day. Two survey vessels operating on the same day count 
as two survey days. This schedule is based on 24-hour operations in the 
offshore, deep-water portion of the Lease Area, and 12-hour operations 
in shallow-water and nearshore areas of the export cable route. Some 
shallow-water HRG activities would occur only during daylight hours. 
Mayflower proposes to begin survey activities on April 1, 2021 and 
conclude by November 30, 2021. However, the proposed IHA would be 
effective for one year from the date of issuance.

Specific Geographic Region

    Mayflower's survey activities would occur in the Northwest Atlantic 
Ocean in the Lease Area which is located approximately 20 nautical 
miles (38 kilometers (km)) south-southwest of Nantucket, Massachusetts 
and covers approximately 515 km\2\. All survey efforts would occur 
within U.S. Federal

[[Page 11932]]

and state waters. Water depths in the Lease Area are approximately 38-
62 meters (m). Surveys would occur within the Lease Area and along a 
potential submarine cable route connecting to landfall at Falmouth, MA 
(see Figure 1). For the purpose of this IHA, the Lease Area and export 
cable route are collectively referred to as the Project Area.
[GRAPHIC] [TIFF OMITTED] TN01MR21.017

Detailed Description of Specific Activity

    Mayflower's proposed marine site characterization surveys includes 
the use of HRG equipment. Survey activities would occur within the 
Lease Area and along an export cable route between the Lease Area and 
Falmouth, Massachusetts. Up to four (4) HRG survey vessels may operate 
concurrently as part of the proposed surveys and are anticipated to 
spend a total of 471 survey days at sea. One vessel would be operating 
primarily in the Lease Area and deep-water sections of the cable route 
(24 hr operations), with a second vessel operating primarily in the 
shallow water portion of the cable route and sometimes into the deep 
water portion of the cable route (either daylight only operations or 24 
hour operations). Up to two (2) shallow-draft vessels would work in 
very shallow waters (daylight only operations). 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.

[[Page 11933]]

    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 
route. The proposed survey in this area will primarily consist of 24-
hour vessel operations, with some 12-hour per day vessel operations 
possible. The Shallow-water Survey Area includes the rest of the export 
cable route in shallow waters and very shallow nearshore waters. 
Depending on vessel availability, survey operations in the shallow 
water area may occur only during daylight periods or involve 24-hour 
survey operations. 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 for the anticipated survey activity are summarized in Table 
1. 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-hr per day operations.

            Table 1--Activity Details for 2021 Mayflower HRG Surveys From April 1 Through November 30
----------------------------------------------------------------------------------------------------------------
                                                                    Approximate     Approximate
                                                                      survey          survey       Active sound
                            Location                               trackline \1\   distance per     source days
                                                                       (km)          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 proposed by Mayflower with 
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 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 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 the following survey equipment types is not reasonably 
expected to result in take of marine mammals for and will not be 
carried forward in the application analysis beyond the brief summaries 
provided below.
     Non-impulsive, parametric SBPs are used for providing high 
data density in sub-bottom profiles that are typically required for 
cable routes, very shallow water, and archaeological surveys. They have 
a narrow beamwidth which significantly reduces the impact range of the 
source while the high frequencies of the source are rapidly attenuated 
in sea water. Because of the high frequency of the source and narrow 
bandwidth, parametric SBPs produce small Level B harassment isopleths. 
No Level B harassment exposures should be reasonably expected from the 
operation of these sources.
     Ultra-short baseline (USBL) positioning systems are used 
to provide high accuracy ranges by measuring the time between the 
acoustic pulses transmitted by the vessel transceiver and a transponder 
(or beacon) necessary to produce the acoustic profile. USBLs have been 
shown to produce extremely small acoustic propagation distances in 
their typical operating configuration. Based on this information, no 
Level B harassment exposures should be reasonably expected from the 
operation of these sources.
     Multibeam echosounders (MBESs) are used to determine water 
depths and general bottom topography. The proposed MBESs all have 
operating frequencies >180 kHz, and are therefore outside the general 
hearing range of marine mammals likely to occur in the Project Area and 
are not likely to affect these species.
     Side scan sonars (SSS) are used for seabed sediment 
classification purposes and to identify natural and man-made acoustic 
targets on the seafloor. The proposed SSSs all have operating 
frequencies >180 kHz, and are therefore outside the general hearing 
range of marine mammals likely to occur in the Project Area and are not 
likely to affect these species.
    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

[[Page 11934]]

survey objectives. Source levels for all equipment listed in Table 2 
came from Crocker and Fratantonio (2016). Detailed explanations of 
source specification are found in Table 7 in Appendix A in the IHA 
application.

      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         0.01-1.9             203             180             3.4               2
     800 J system...............
    Applied Acoustics Dura-Spark        0.01-1.9             203             180             3.4               2
     UHD 400 tips, up to 800 J..
Boomer:
    Applied Acoustics S-Boom              0.01-5             205              61             0.6               3
     Triple 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

    Sections 3 and 4 of the application summarize available information 
regarding status and trends, distribution and habitat preferences, and 
behavior and life history, of the potentially affected species. 
Additional information regarding population trends and threats may be 
found in NMFS's Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species 
(e.g., physical and behavioral descriptions) may be found on NMFS's 
website (https://www.fisheries.noaa.gov/find-species).
    Table 3 lists all species or stocks for which take is expected and 
proposed to be authorized for this action, and summarizes information 
related to the population or stock, including regulatory status under 
the MMPA and Endangered Species Act (ESA) and potential biological 
removal (PBR), where known. For taxonomy, NMFS follows Committee on 
Taxonomy (2020). PBR is defined by the MMPA as the maximum number of 
animals, not including natural mortalities, that may be removed from a 
marine mammal stock while allowing that stock to reach or maintain its 
optimum sustainable population (as described in NMFS's SARs). While no 
mortality is anticipated or authorized here, PBR and annual serious 
injury and mortality from anthropogenic sources are included here as 
gross indicators of the status of the species and other threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total number estimated within a particular study or Project Area. 
NMFS's stock abundance estimates for most species represent the total 
estimate of individuals within the geographic area, if known, that 
comprises that stock. For some species, this geographic area may extend 
beyond U.S. waters. All managed stocks in this region are assessed in 
NMFS's U.S. Atlantic SARs. All values presented in Table 3 are the most 
recent available at the time of publication and are available in the 
2019 Atlantic and Gulf of Mexico Marine Mammal SARs (Hayes et al., 
2020), available online at: www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region and 
draft 2020 Atlantic and Gulf of Mexico Marine Mammal SARs available 
online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/draft-marine-mammal-stock-assessment-reports.

                    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 \3\   Annual M/
                                                                                                \1\         abundance  survey) \2\               SI \3\
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                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Balaenidae:
    North Atlantic right whale......  Eubalaena glacialis....  Western North Atlantic.  E/D; Y              412 (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:

[[Page 11935]]

 
    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 \4\...................  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 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\ 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' 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.
\4\ 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. All species that could potentially occur in 
the proposed survey areas are included in Table 5 of the IHA 
application. However, the temporal and/or spatial occurrence of several 
species listed in Table 5 in the IHA application is such that take of 
these species is not expected to occur. The blue whale (Balaenoptera 
musculus), Cuvier's beaked whale (Ziphius cavirostris), four species of 
Mesoplodont beaked whale (Mesoplodon spp.), dwarf and pygmy sperm whale 
(Kogia sima and Kogia breviceps), and striped dolphin (Stenella 
coeruleoalba), typically occur further offshore than the Project Area, 
while short-finned pilot whales (Globicephala macrorhynchus) and 
Atlantic spotted dolphins (Stenella frontalis) are typically found 
further south than the Project Area (Hayes et al., 2020). There are 
stranding records of harp seals (Pagophilus groenlandicus) in 
Massachusetts, but the species typically occurs north of the Project 
Area and appearances in Massachusetts usually occur between January and 
May, outside of the proposed survey dates (Hayes et al., 2020). As take 
of these species is not anticipated as a result of the proposed 
activities, these species are not analyzed further.
    A description of the marine mammals for which take is likely to 
occur may be found in the documents supporting Mayflower's previous IHA 
covering the Lease Area and potential submarine cable routes (85 FR 
45578; July 29, 2020), the same geographic areas where Mayflower has 
proposed activities for this IHA. The most recent draft SARs data has 
been included in Table 3. The only other notable changes from the 
previous IHA pertain to updated Unusual Mortality Event (UME) data for 
North Atlantic right whales, humpback whales, minke whales, and 
pinnipeds.
    At the time of the issuance of the previous IHA to Mayflower 85 FR 
45578; July 29, 2020), 30 North Atlantic right whales have been 
recorded as confirmed dead or stranded. As of January 21, 2021, the 
number has increased to 32. Humpback whale mortalities have increased 
from 111 to 145 and minke whale mortalities increased from 79 to 103 
cases over the same time period. The number of recorded pinniped 
mortalities has not been updated since issuance of Mayflower's previous 
IHA and remains at 3,152 cases.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Current data indicate that not all marine 
mammal species have equal hearing capabilities (e.g., Richardson et 
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect 
this, Southall et al. (2007) recommended that marine mammals be divided 
into functional hearing groups based on directly measured or estimated 
hearing ranges on the basis of available behavioral response data, 
audiograms derived using auditory evoked potential techniques, 
anatomical modeling, and other data. Note that no direct measurements 
of hearing ability have been successfully completed for mysticetes 
(i.e., low-frequency cetaceans). Subsequently, in 2018 NMFS published a 
Technical Guidance for Assessing the Effects of Anthropogenic Sound on 
Marine Mammal Hearing which described generalized hearing ranges for 
these marine mammal hearing groups. Generalized hearing ranges were 
chosen

[[Page 11936]]

based on the approximately 65 decibel (dB) threshold from the 
normalized composite audiograms, with the exception for lower limits 
for low-frequency cetaceans where the lower bound was deemed to be 
biologically implausible and the lower bound from Southall et al. 
(2007) retained. Marine mammal hearing groups and their associated 
hearing ranges are provided in Table 4.

           Table 4--Marine Mammal Hearing Groups (NMFS, 2018)
------------------------------------------------------------------------
                                                    Generalized hearing
                  Hearing group                           range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen whales)....  7 Hz to 35 kHz.
Mid-frequency (MF) cetaceans (dolphins, toothed   150 Hz to 160 kHz.
 whales, beaked whales, bottlenose whales).
High-frequency (HF) cetaceans (true porpoises,    275 Hz to 160 kHz.
 Kogia, river dolphins, cephalorhynchid,
 Lagenorhynchus cruciger & L. australis).
Phocid pinnipeds (PW) (underwater) (true seals).  50 Hz to 86 kHz.
Otariid pinnipeds (OW) (underwater) (sea lions    60 Hz to 39 kHz.
 and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
  composite (i.e., all species within the group), where individual
  species' hearing ranges are typically not as broad. Generalized
  hearing range chosen based on ~65 dB threshold from normalized
  composite audiogram, with the exception for lower limits for LF
  cetaceans (Southall et al. 2007) and PW pinniped (approximation).

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth et al., 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information. 
Fourteen marine mammal species (12 cetacean and two pinniped (both 
phocid) species) have the reasonable potential to co-occur with the 
proposed survey activities. Of the cetacean species that may be 
present, six are classified as low-frequency cetaceans (i.e., all 
mysticete species), five are classified as mid-frequency cetaceans 
(i.e., all delphinid species and the sperm whale), and one is 
classified as high-frequency cetaceans (i.e., harbor porpoise).

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 previous IHA covering the Lease Area and 
potential submarine cable routes (85 FR 45578; July 29, 2020). 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 
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 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 [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

[[Page 11937]]

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 SELcum and peak sound pressure level metrics. As dual 
metrics, NMFS considers onset of PTS (Level A harassment) to have 
occurred when either one of the two metrics is exceeded (i.e., metric 
resulting in the largest isopleth). The SELcum metric 
considers both level and duration of exposure, as well as auditory 
weighting functions by marine mammal hearing group.
    These thresholds are provided in Table 5 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 5--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.

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 
methodology for determining the rms sound pressure level 
(SPLrms) at 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) be incorporated in the method 
described above to estimate isopleth distances to the Level B 
harassment threshold. Table 2 shows the HRG equipment types that may be 
used during the proposed surveys and the sound levels associated with 
those HRG equipment types.

                       Table 6--Estimated Distances to Level A and Level B Harassment Thresholds for the Planned Survey Equipment
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                         Distance (m) to Level A harassment threshold \1\                   Distance to
                                                         --------------------------------------------------------------------------------     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:

[[Page 11938]]

 
    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. For the peak SPL metric, the model is 
a series of equations that accounts for both seawater absorption and 
HRG equipment beam patterns (for all HRG sources with beam widths 
larger than 90[deg], it was assumed these sources were 
omnidirectional). For the SELcum metric, a model was 
developed that accounts for the hearing sensitivity of the marine 
mammal group, seawater absorption, and beam width for downwards-facing 
transducers. Details of the modeling methodology for both the peak SPL 
and SELcum metrics are provided in Appendix A of the IHA 
application. This model entails the following steps:
    1. Weighted broadband source levels were calculated by assuming a 
flat spectrum between the source minimum and maximum frequency, 
weighted the spectrum according to the marine mammal hearing group 
weighting function (NMFS 2018), and summed across frequency;
    2. Propagation loss was modeled as a function of oblique range;
    3. Per-pulse SEL was modeled for a stationary receiver at a fixed 
distance off a straight survey line, using a vessel transit speed of 
3.5 knots and source-specific pulse length and repetition rate. The 
off-line distance is referred to as the closest point of approach (CPA) 
and was performed for CPA distances between 1 m and 10 km. The survey 
line length was modeled as 10 km long (analysis showed longer survey 
lines increased SEL by a negligible amount). SEL is calculated as SPL + 
10 log10 T/15 dB, where T is the pulse duration;
    4. The SEL for each survey line was calculated to produce curves of 
weighted SEL as a function of CPA distance; and
    5. The curves from Step 4 above were used to estimate the CPA 
distance to the impact criteria.
    Note that in the modeling methods described above and in Appendix A 
of the IHA application, sources that operate with a repetition rate 
greater than 10 Hz were assessed with the non-impulsive (intermittent) 
source criteria while sources with a repetition rate equal to or less 
than 10 Hz were assessed with the impulsive source criteria. NMFS does 
not agree with this step in the modeling assessment, which results in 
nearly all HRG sources being classified as impulsive.
    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, listed in Table 
1. 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 6) 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.
    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.
    As shown in Table 1, up to 14,350 km of survey activity may occur 
from April through November 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 route, and (2) the shallow water 
portion of the cable route including very shallow water sections of the 
cable route.
    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

[[Page 11939]]

distance of 141 m, the total daily ensonified area is estimated to be 
22.6 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 8-month period of anticipated activity results in approximately 
13.5 and 34.2 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\.

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 marine mammal monitoring 
report under the previous IHA covering a period of 330 vessel days 
utilizing three survey vessels. A total of 415 individual 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 within the two survey areas were 
derived from habitat-based density modeling results reported by Roberts 
et al. (2016, 2017, 2018, 2020). 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 (but see 
North Atlantic right whale discussion below). 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 7, Table 8).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 Table 7 and Table 8.
    The estimated monthly density of seals provided in Roberts et al. 
(2018) includes all seal species present in the region as a single 
guild. 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 7, Table 8).
    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 Protected Species 
Observers (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 November 2021. 
Note that if the proposed survey activities extend beyond November 
2021, the monthly 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 7--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
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                      Estimated monthly densities (individuals/km\2\)
                             Species                             ---------------------------------------------------------------------------------------
                                                                     Apr        May        Jun        Jul        Aug        Sep        Oct        Nov
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mysticetes:
    Fin Whale *.................................................     0.0028     0.0031     0.0033     0.0033     0.0030     0.0025     0.0015     0.0013
    Humpback Whale..............................................     0.0012     0.0013     0.0014     0.0011     0.0005     0.0011     0.0011     0.0005
    Minke Whale.................................................     0.0016     0.0026     0.0025     0.0010     0.0007     0.0008     0.0008     0.0003
    North Atlantic Right Whale *................................     0.0081     0.0038     0.0003     0.0000     0.0000     0.0000     0.0001     0.0006
    Sei Whale *.................................................     0.0006     0.0005     0.0002     0.0001     0.0000     0.0001     0.0000     0.0000
Odontocetes:

[[Page 11940]]

 
    Atlantic White-Sided Dolphin................................     0.0360     0.0685     0.0656     0.0465     0.0250     0.0256     0.0326     0.0357
    Common Bottlenose Dolphin...................................     0.0104     0.0118     0.0262     0.0541     0.0415     0.0517     0.0574     0.0278
    Harbor Porpoise.............................................     0.0846     0.0404     0.0184     0.0122     0.0112     0.0091     0.0081     0.0197
    Pilot Whales................................................     0.0068     0.0068     0.0068     0.0068     0.0068     0.0068     0.0068     0.0068
    Risso's Dolphin.............................................     0.0001     0.0002     0.0002     0.0005     0.0010     0.0008     0.0003     0.0004
    Short-Beaked Common Dolphin.................................     0.0266     0.0462     0.0572     0.0623     0.1078     0.1715     0.1806     0.1214
    Sperm Whale *...............................................     0.0001     0.0001     0.0001     0.0004     0.0004     0.0002     0.0002     0.0001
Pinnipeds:
    Seals (Harbor and Gray).....................................     0.1491     0.1766     0.0262     0.0061     0.0033     0.0041     0.0059     0.0102
--------------------------------------------------------------------------------------------------------------------------------------------------------


    Table 8--Average Monthly Densities for Species That May Occur Along the Shallow-Water Section of the Cable Route During the Planned Survey Period
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                      Estimated monthly densities (individuals/km\2\)
                             Species                             ---------------------------------------------------------------------------------------
                                                                     Apr        May        Jun        Jul        Aug        Sep        Oct        Nov
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mysticetes:
    Fin Whale *.................................................     0.0002     0.0003     0.0003     0.0003     0.0003     0.0003     0.0002     0.0001
    Humpback Whale..............................................     0.0001     0.0000     0.0001     0.0001     0.0000     0.0001     0.0002     0.0001
    Minke Whale.................................................     0.0003     0.0004     0.0002     0.0000     0.0000     0.0000     0.0000     0.0000
    North Atlantic Right Whale *................................     0.0004     0.0001     0.0000     0.0000     0.0000     0.0000     0.0000     0.0001
    Sei Whale *.................................................     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000
Odontocetes:
    Atlantic White-Sided Dolphin................................     0.0009     0.0012     0.0010     0.0006     0.0005     0.0008     0.0014     0.0011
    Common Bottlenose Dolphin...................................     0.0211     0.0377     0.2308     0.4199     0.3211     0.3077     0.1564     0.0813
    Harbor Porpoise.............................................     0.0010     0.0013     0.0048     0.0023     0.0037     0.0036     0.0003     0.0214
    Pilot Whales................................................     0.0000     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     0.0000
    Short-Beaked Common Dolphin.................................     0.0003     0.0004     0.0003     0.0002     0.0006     0.0009     0.0008     0.0010
    Sperm Whale *...............................................     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000     0.0000
Pinnipeds:
    Seals (Harbor and Gray).....................................     1.3897     1.0801     0.2496     0.0281     0.0120     0.0245     0.0826     0.5456
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 7 and Table 8 by the respective monthly 
ensonified area within each survey area. The results are shown in the 
``Calculated Take'' columns of Table 9. 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 9).
    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 35-week survey period in 2021. 
These results are shown in the ``Sightings-based Takes'' column of 
Table 9. The larger of the take estimates from the density-based and 
sightings-based methods are shown in the ``Requested Take'' column, 
except as noted below.
    Based on the sightings data Mayflower requested authorization of 37 
humpback whale, 15 minke whale, and 2,153 common dolphin takes by Level 
B harassment. Using the best available density data (Roberts et al. 
2016, 2017, 2018, 2020), Mayflower requested 85 white-sided dolphin, 
483 bottlenose dolphin, 61 harbor porpoise takes by Level B harassment. 
NMFS agrees with Mayflower requests and proposes to authorize take of 
these species in the numbers requested.
    For five species, North Atlantic right whale, sei whale, pilot 
whales, Risso's dolphin, and sperm whale the Requested 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). 
Mayflower requested that three times the average group size be 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 requested number of takes by Level B harassment as a percentage 
of the ``best available'' abundance estimates provided in the NMFS 
Stock Assessment Reports (Hayes et al. 2020) are also provided in Table 
9. For the seal guild, the estimated abundance for both gray and harbor 
seals was summed in Table 9. Mayflower requested and NMFS proposes to 
authorize 989 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

[[Page 11941]]

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 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 by a PSO, 
so Mayflower requested and NMFS proposes to authorize take consistent 
with other species (i.e. three times average group size).

                              Table 9--Number of Level B Harassment Takes Proposed and Percentages of Each Stock Abundance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                    Density-based take by
                                                        survey region          Total
                                                 --------------------------   density-                                                        Percent of
                     Species                       Lease area                  based       Density-    Sightings-   Requested    Abundance    NMFS stock
                                                     & deep      Shallow     calculated  based takes  based takes      take         NMFS      abundance
                                                  water cable  water cable     takes
                                                     route
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fin Whale *.....................................          5.1          0.5          5.7            6            2            6        3,006          0.2
Humpback Whale..................................          2.0          0.2          2.2            3           37           37        1,396          2.7
Minke Whale.....................................          2.5          0.3          2.8            3           15           15        2,591          0.6
North Atlantic Right Whale*.....................          3.2          0.2          3.4            4            0        9 \1\          428          2.1
Sei Whale *.....................................          0.4          0.0          0.4            1            0        6 \1\           28         21.4
Atlantic White-Sided Dolphin....................         83.0          2.0         85.0           85            0           85       31,912          0.3
Common Bottlenose Dolphin.......................         69.5        413.0        482.5          483           64          483       62,851          0.8
Harbor Porpoise.................................         50.4         10.1         60.5           61            0           61       75,079          0.1
Pilot Whales....................................         13.4          0.0         13.5           14           18       27 \1\       68,139          0.0
Risso's Dolphin.................................          0.8          0.0          0.8            1            0       18 \1\       35,493          0.1
Short-Beaked Common Dolphin.....................        191.4          1.2        192.6          193        2,153        2,153       80,227          2.7
Sperm Whale *...................................          0.4          0.0          0.4            1            0        6 \1\        4,349          0.1
Seals (Harbor and Gray).........................         94.4        894.2        988.6          989          154          989      102,965          1.0
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Denotes species listed under the Endangered Species Act.
\1\ Value reflects a rounding up of three (3) times the mean group size calculated from survey data in this region.

Proposed Mitigation

    In order to issue an IHA under section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to the 
activity, and other means of effecting the least practicable impact on 
the species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of the species or stock for taking for certain 
subsistence uses (latter not applicable for this action). NMFS 
regulations require applicants for incidental take authorizations to 
include information about the availability and feasibility (economic 
and technological) of equipment, methods, and manner of conducting the 
activity or other means of effecting the least practicable adverse 
impact upon the affected species or stocks and their habitat (50 CFR 
216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, NMFS 
carefully considers two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers the nature of the potential adverse impact being 
mitigated (likelihood, scope, range). It further considers the 
likelihood that the measure will be effective if implemented 
(probability of accomplishing the mitigating result if implemented as 
planned), the likelihood of effective implementation (probability 
implemented as planned); and
    (2) The practicability of the measures for applicant 
implementation, which may consider such things as cost, and impact on 
operations.

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 exclusion zones (EZ) 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 
exclusion zones prior to the initiation of ramp-up of HRG equipment. 
During this period, the exclusion zone 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 exclusion zone. If a 
marine mammal is observed within an exclusion zone during the pre-
clearance period, ramp-up may not begin until the animal(s) has been 
observed exiting its respective exclusion zone 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.

[[Page 11942]]

    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 exclusion zone. Ramp-up will continue if the animal has been 
observed exiting its respective exclusion zone 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 exclusion zone. 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 
exclusion zone 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 exclusion zones. 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 exclusion zone 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.
     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 right whale, other whale (defined in this 
context as sperm whales or baleen whales other than right whales), or 
other marine mammal.
     All vessels (e.g., source vessels, chase vessels, supply 
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 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

[[Page 11943]]

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

    In order to issue an IHA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth requirements pertaining to the 
monitoring and reporting of such taking. The MMPA implementing 
regulations at 50 CFR 216.104(a)(13) indicate that requests for 
authorizations must include the suggested means of accomplishing the 
necessary monitoring and reporting that will result in increased 
knowledge of the species and of the level of taking or impacts on 
populations of marine mammals that are expected to be present in the 
proposed action area. Effective reporting is critical both to 
compliance as well as ensuring that the most value is obtained from the 
required monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
     Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
     Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) Action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the action; or (4) biological or 
behavioral context of exposure (e.g., age, calving or feeding areas);
     Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
     How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
     Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and
     Mitigation and monitoring effectiveness.

Proposed Monitoring Measures

    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 exclusion zones, during all HRG survey 
operations. PSOs will visually monitor and identify marine mammals, 
including those approaching or entering the established exclusion zones 
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 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 to exclusion zones. 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;

[[Page 11944]]

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); and
     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); and
     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 
Stranding Coordinator as soon as feasible. 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 and the NMFS New England/Mid-
Atlantic Stranding Coordinator 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

[[Page 11945]]

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 9 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 section, 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.
    In addition to being temporary, the maximum expected harassment 
zone around a survey vessel is 141 m per vessel during use of sparkers. 
Therefore, the ensonified area surrounding each vessel is 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 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. Because of the temporary nature 
of the disturbance and the availability of similar habitat and 
resources in the surrounding area, the impacts to marine mammals and 
the food sources that they utilize are not expected to cause 
significant or long-term consequences for individual marine mammals or 
their populations.
    Furthermore, the proposed Project Area encompasses or is in close 
proximity to feeding biologically important areas (BIAs) for right 
whales (February-April), humpback whales (March-December), fin whales 
(March-October), and sei whales (May-November) which were discussed in 
the previous IHA (85 FR 45578; July 29, 2020) Most of these feeding 
BIAs are extensive and sufficiently large (705 km\2\ and 3,149 km\2\ 
for 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. Any 
whales temporarily displaced from the parts of the BIAs that overlap 
with the proposed Project Area would be expected to have sufficient 
remaining feeding habitat available to them, and would not be prevented 
from feeding in other areas within the biologically important feeding 
habitat. In addition, any displacement of whales from the BIA or 
interruption of foraging bouts would be expected to be temporary in 
nature. Therefore, NMFS does not expect impacts to whales within 
feeding BIAs to affect the fitness of any large whales. Accordingly, 
NMFS does not anticipate impacts from the 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 proposed Project 
Area. Furthermore, there is no designated critical habitat for any ESA-
listed marine mammals in the proposed Project Area.

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 right whales. 
In addition to the right whale feeding BIA noted above, the proposed 
Project Area overlaps a migratory corridor Biologically Important Area 
(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 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 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.

[[Page 11946]]

NMFS does not anticipate North Atlantic right whales takes that would 
result from Mayflower's proposed activities would impact annual rates 
of recruitment or survival. Thus, any takes that occur would not result 
in population level impacts for the species.

Other Marine Mammal Species With Active UMEs

    As noted in the previous IHA, there are several active UMEs 
occurring in the vicinity of Mayflower's 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 EEZ 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 9, 
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 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.
    In summary and as described above, the following factors primarily 
support our preliminary determination that the impacts resulting from 
this activity are not expected to adversely affect the 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 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; and
     The proposed mitigation measures, including visual 
monitoring and shutdowns, are expected to minimize potential impacts to 
marine mammals.
    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 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 9. 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.

[[Page 11947]]

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 (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 Office of Protected Resources 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 
route to landfall at Falmouth, Massachusetts 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 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 proposed IHA for the proposed 
marine site characterization surveys. NMFS also requests at this time 
comment on the potential Renewal of this proposed IHA as described in 
the paragraph below. Please include with your comments any supporting 
data or literature citations to help inform decisions on the request 
for this IHA or a subsequent Renewal IHA.
    On a case-by-case basis, NMFS may issue a one-time, one-year 
Renewal IHA following notice to the public providing 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 Activities section of this notice is planned or 
(2) the activities as described in the Description of Proposed 
Activities section of this notice would not be completed by the time 
the IHA expires and a Renewal would allow for completion of the 
activities beyond that described in the Dates and Duration section of 
this notice, provided all of the following conditions are met:
     A request for renewal is received no later than 60 days 
prior to the needed Renewal IHA effective date (recognizing that the 
Renewal IHA expiration date cannot extend beyond one year from 
expiration of the initial IHA);
     The request for renewal must include the following:
    1. An explanation that the activities to be conducted under the 
requested Renewal IHA are identical to the activities analyzed under 
the initial IHA, are a subset of the activities, or include changes so 
minor (e.g., reduction in pile size) that the changes do not affect the 
previous analyses, mitigation and monitoring requirements, or take 
estimates (with the exception of reducing the type or amount of take); 
and
    2. A preliminary monitoring report showing the results of the 
required monitoring to date and an explanation showing that the 
monitoring results do not indicate impacts of a scale or nature not 
previously analyzed or authorized.
    Upon review of the request for Renewal, the status of the affected 
species or stocks, and any other pertinent information, NMFS determines 
that there are no more than minor changes in the activities, the 
mitigation and monitoring measures will remain the same and 
appropriate, and the findings in the initial IHA remain valid.

    Dated: February 24, 2021.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2021-04161 Filed 2-26-21; 8:45 am]
BILLING CODE 3510-22-P