Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Site Characterization Surveys Off the Coast of Massachusetts, 45578-45596 [2020-16357]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 85, Number 146 (Wednesday, July 29, 2020)]
[Notices]
[Pages 45578-45596]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-16357]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XA240]


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; issuance of an incidental harassment authorization.

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SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that NMFS has issued an incidental harassment authorization (IHA) to 
Mayflower Wind Energy LLC (Mayflower) to incidentally harass, by Level 
B harassment only, marine mammals during 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.

DATES: This authorization is effective from July 23, 2020 to July 22, 
2021.

FOR FURTHER INFORMATION CONTACT: Amy Fowler, 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.

Summary of Request

    On January 17, 2020, NMFS received a request from Mayflower for an 
IHA to take marine mammals incidental to site characterization surveys 
in the area of the Commercial Lease of Submerged Lands for Renewable 
Energy Development on the Outer Continental Shelf (OCS-A 0521; Lease 
Area) and a submarine export cable route connecting the Lease Area to 
landfall in Falmouth, Massachusetts. A revised application was received 
on April 9, 2020. NMFS deemed that request to be adequate and complete. 
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.

Description of the Specified Activity

    Mayflower plans to conduct marine site characterization surveys, 
including high-resolution geophysical (HRG) and geotechnical surveys, 
in the area of Commercial Lease of Submerged Lands for Renewable Energy 
Development on the Outer Continental Shelf #OCS-A 0521 (Lease Area), 
located approximately 60 kilometers (km) south of Martha's Vineyard, 
Massachusetts, and along a potential submarine cable route to landfall 
at Falmouth, Massachusetts.
    The purpose of the planned surveys is to acquire geotechnical and 
HRG 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 export cable route to support development of 
offshore wind energy facilities. Up to three survey vessels may operate 
concurrently as part of the surveys, but the three vessels will spend 
no more than a combined total of 215 days at sea. Surveys are expected 
to occur over a three-month period, beginning upon issuance of the IHA. 
Underwater sound resulting from Mayflower's site characterization 
surveys has the potential to result in incidental take of marine 
mammals in the form of behavioral harassment.
    The HRG survey activities planned by Mayflower are described in 
detail in the notice of proposed IHA (85 FR 31856; May 27, 2020). The 
HRG equipment planned for use is shown in Table 1.

                                          Table 1--Summary of HRG Survey Equipment Planned for Use by Mayflower
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                               Pulse
        HRG equipment category          Specific HRG equipment     Operating frequency     Source level      Beamwidth     Typical pulse    repetition
                                                                       range (kHz)           (dB rms)        (degrees)     duration (ms)     rate (Hz)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sparker..............................  Geomarine Geo-Spark 800   0.25 to 5..............             203             180             3.4               2
                                        J system.

[[Page 45579]]

 
Sub-bottom profiler..................  Edgetech 3100 with SB-2-  2 to 16................             179              65              10              10
                                        16S towfish.
                                       Innomar SES-2000 Medium-  85 to 115..............             241               2               2              40
                                        100 Parametric.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    As described above, a detailed description of the planned HRG 
surveys is provided in the Federal Register notice for the proposed IHA 
(85 FR 31856; May 27, 2020). Since that time, no changes have been made 
to the planned HRG survey activities. Therefore, a detailed description 
is not provided here. Please refer to that Federal Register notice for 
the description of the specific activity. Mitigation, monitoring, and 
reporting measures are described in detail later in this document 
(please see Mitigation and Monitoring and Reporting below).

Comments and Responses

    A notice of NMFS's proposal to issue an IHA to Mayflower was 
published in the Federal Register on May 27, 2020 (85 FR 31856). That 
notice described, in detail, Mayflower's activity, the marine mammal 
species that may be affected by the activity, and the anticipated 
effects on marine mammals. During the 30-day public comment period, 
NMFS received comment letters from the Marine Mammal Commission 
(Commission) and a group of environmental non-governmental 
organizations (ENGOs) including the Natural Resources Defense Council, 
National Wildlife Foundation, Conservation Law Foundation, Whale and 
Dolphin Conservation North America, Defenders of Wildlife, Humane 
Society of the United States, Humane Society Legislative Fund, 
International Fund for Animal Welfare, Mass Audubon, Marine Mammal 
Alliance Nantucket, NY4WHALES, Surfrider Foundation, Friends of the 
Earth, Ocean Conservation Research, and Sanctuary Education Advisory 
Specialists. NMFS has posted the comments online at: 
www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-other-energy-activities-renewable. A summary of the 
public comments received from the Commission and ENGOs as well as NMFS' 
responses to those comments are below.
    Comment 1: The Commission recommends that NMFS (1) prohibit 
Mayflower and other action proponents from using the impulsive Level A 
harassment thresholds for estimating the extents of the Level A 
harassment zones for non-impulsive sources (i.e., echosounders, 
shallow-penetration sub-bottom profilers (SBPs), pingers, etc.) and (2) 
require action proponents to use the correct Level A harassment 
thresholds in all future applications. The Commission further 
recommends that NMFS justify why it is allowing action proponents to 
characterize sources in a manner inconsistent with its own acoustic 
guidance (NMFS 2018).
    Response: NMFS concurs with the Commission's recommendations and 
will work to ensure that applicants are using the correct harassment 
thresholds in all future applications. As described in the notice of 
proposed IHA, NMFS does not agree with Mayflower's characterization of 
certain HRG sources as impulsive sources. However, this 
characterization results in more conservative modeling results and take 
estimates than if the Level A harassment thresholds for non-pulse 
sources were used and in this case, no Level A harassment is predicted 
or authorized.
    Comment 2: The Commission recommends that NMFS use its revised user 
spreadsheet, in-beam source levels, the actual beamwidth proposed to be 
used, and the maximum water depth in the survey area to estimate the 
Level B harassment zones for Mayflower's activities and all future 
proposed authorizations involving HRG sources.
    Response: NMFS' interim guidance for determining Level B harassment 
zones from HRG sources does incorporate operating frequency and beam 
width. We strongly recommend that applicants employ these tools, as we 
believe they are generally the best methodologies that are currently 
available. However, applicants are free to develop additional models or 
use different tools if they believe they are more representative of 
real-world conditions. NMFS will evaluate those tools and either use 
them where appropriate, or recommend changes. In this case, we note 
that the Level B harassment zones calculated by Mayflower using JASCO's 
model are the same as those calculated using NMFS's interim guidance 
with the exception of the Innomar parametric SBP, for which JASCO's 
model calculates a more conservative Level B harassment zone by 
incorporating out-of-beam sound levels.
    Comment 3: To maximize efficiencies and ensure best available 
science is being used, the Commission recommends that NMFS consult with 
its acoustic experts to determine how to estimate Level A harassment 
zones accurately, what Level A harassment zones are actually expected, 
and whether it is necessary to estimate Level A harassment zones for 
HRG surveys in general.
    Response: NMFS agrees with the Commission's recommendation and is 
working with our acoustic experts to evaluate the appropriate methods 
for determining the potential for Level A harassment from HRG surveys.
    Comment 4: The Commission recommends that NMFS and BOEM expedite 
efforts to develop and finalize, in the next six months, methodological 
and signal processing standards for HRG sources. Those standards should 
be used by action proponents that conduct HRG surveys and that either 
choose to conduct in-situ measurements to inform an authorization 
application or are required to conduct measurements to fulfill a lease 
condition set forth by BOEM.
    Response: NMFS agrees with the Commission that methodological and 
signal processing standards for HRG sources is warranted and is working 
on developing such standards. However, the effort is resource-dependent 
and NMFS cannot ensure such standards will be developed within the 
Commission's preferred time frame.
    Comment 5: The Commission recommends that NMFS evaluate the impacts 
of sound sources consistently across all action proponents and deem 
sources de minimis in a consistent manner for all proposed incidental 
harassment authorizations and rulemakings. This has the potential to 
reduce burdens on both action proponents and NMFS.

[[Page 45580]]

    Response: NMFS concurs with the Commission's recommendation and is 
currently working together with BOEM to develop a tool to assist 
applicants and NMFS in more quickly and efficiently identifying 
activities and mitigation approaches that are unlikely to result in 
take of marine mammals.
    Comment 6: The Commission recommends that NMFS consider whether, in 
such situations involving HRG surveys, incidental harassment 
authorizations are necessary given the small size of the Level B 
harassment zones, the proposed shutdown requirements, and the added 
protection afforded by the lease-stipulated exclusion zones. 
Specifically, the Commission states that NMFS should evaluate whether 
taking needs to be authorized for those sources that are not considered 
de minimis, including sparkers and boomers, and for which 
implementation of the various mitigation measures should be sufficient 
to avoid Level B harassment takes.
    Response: NMFS has evaluated whether taking needs to be authorized 
for those sources that are not considered de minimis, including 
sparkers and boomers, factoring into consideration the effectiveness of 
mitigation and monitoring measures, and we have determined that 
implementation of mitigation and monitoring measures cannot ensure that 
all take can be avoided during all HRG survey activities under all 
circumstances at this time. If and when we are able to reach such a 
conclusion, we will re-evaluate our determination that incidental take 
authorization is warranted for these activities.
    Comment 7: The Commission recommends that NMFS require Mayflower to 
report as soon as possible and cease project activities immediately in 
the event of an unauthorized injury or mortality of a marine mammal 
from a vessel strike until the NMFS Office of Protected Resources and 
the NMFS New England/Mid-Atlantic Regional Stranding Coordinator 
determine whether additional measures are necessary to minimize the 
potential for additional unauthorized takes.
    Response: NMFS has imposed a suite of measures in this IHA to 
reduce the risk of vessel strikes and does not anticipate, and has not 
authorized, any takes associated with vessel strikes. Further, in the 
event of a ship strike Mayflower is required both to collect and report 
an extensive suite of information that NMFS has identified in order to 
evaluate the ship strike, and to notify OPR and the New England/Mid-
Atlantic Regional Stranding Coordinator as soon as feasible. At that 
point, as the Commission suggests, NMFS would work with the applicant 
to determine whether there are additional mitigation measures or 
modifications that could further reduce the likelihood of vessel strike 
for the activities. However, given the existing requirements and the 
very low likelihood of a vessel strike occurring, the protective value 
of ceasing operations while NMFS and Mayflower discuss potential 
additional mitigations in order to avoid a second highly unlikely event 
during that limited period is unclear, while a requirement for project 
activities to cease would not be practicable for a vessel that is 
operating on the open water. Therefore, NMFS does not concur that the 
measure is warranted and we have not included this requirement in the 
authorization. NMFS retains authority to modify the IHA and cease all 
activities immediately based on a vessel strike and will exercise that 
authority if warranted.
    Comment 8: The Commission recommends that NMFS specify that IHA 
Renewals are a one-time opportunity in all Federal Register notices 
requesting comments on the possibility of an IHA Renewal and in all 
associated proposed and final IHAs.
    Response: NMFS concurs and has specified this in the final IHA for 
Mayflower's activities and will include this in all future Federal 
Register notices and proposed and final authorizations.
    Comment 9: The Commission recommends that NMFS refrain from issuing 
renewals for any authorization and instead use its abbreviated Federal 
Register notice process as that process is similarly expeditious and 
fulfills NMFS's intent to maximize efficiencies.
    Response: NMFS does not agree with the Commission and, therefore, 
does not adopt the Commission's recommendations. NMFS believes IHA 
renewals can be appropriate in certain limited circumstances, which are 
described in the conditions for the IHA. NMFS has previously provided 
responses to this recommendation in multiple notices, including 84 FR 
52464 (October 02, 2019), and will provide a more detailed response 
within 120 days, as required by section 202(d) of the MMPA.
    Comment 10: The ENGOs recommended a seasonal restriction on site 
assessment and characterization activities in the Project Areas with 
the potential to harass North Atlantic right whales (Eubalaena 
glacialis) between January 1 and April 30, 2021.
    Response: In evaluating how mitigation may or may not be 
appropriate to ensure the least practicable adverse impact on species 
or stocks and their habitat, we carefully consider two primary factors: 
(1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat; and 
(2) the practicability of the measures for applicant implementation, 
which may consider such things as relative cost and impact on 
operations.
    NMFS is concerned about the status of the North Atlantic right 
whale population given that an unusual mortality event (UME) has been 
in effect for this species since June of 2017 and that there have been 
a number of recent mortalities. While the ensonified areas contemplated 
for any single HRG vessel are comparatively small and the anticipated 
resulting effects of exposure relatively lower-level, the potential 
impacts of multiple HRG vessels (up to three vessels are planned for 
use by Mayflower) operating simultaneously in areas of higher right 
whale density are not well-documented and warrant caution. However, 
Mayflower does not plan to conduct HRG survey operations during the 
timeframe suggested by the ENGOs, and their BOEM-approved survey plan 
requires surveys to end in September 2020. If Mayflower requests future 
authorizations that include HRG survey operations between January 1 and 
April 30, NMFS will consider the possibility of including seasonal 
restrictions.
    Comment 11: The ENGOs recommended a prohibition on the commencement 
of geophysical surveys at night or during times of poor visibility. 
They stated that ramp up should occur during daylight hours only, to 
maximize the probability that North Atlantic right whales are detected 
and confirmed clear of the exclusion zone.
    Response: We acknowledge the limitations inherent in detection of 
marine mammals at night. However, no injury is expected to result even 
in the absence of mitigation, given the very small estimated Level A 
harassment zones. Any potential impacts to marine mammals authorized 
for take would be limited to short-term behavioral responses. 
Restricting surveys in the manner suggested by the commenters may 
reduce marine mammal exposures by some degree in the short term, but 
would not result in any significant reduction in either intensity or 
duration of noise exposure. Vessels would also potentially be on the 
water for an extended time introducing noise into the marine 
environment. The restrictions recommended by the

[[Page 45581]]

commenters could result in the surveys spending increased time on the 
water, which may result in greater overall exposure to sound for marine 
mammals and increase the risk of a vessel strike; thus the commenters 
have not demonstrated that such a requirement would result in a net 
benefit. Furthermore, restricting the applicant to ramp-up only during 
daylight hours would have the potential to result in lengthy shutdowns 
of the survey equipment, which could result in the applicant failing to 
collect the data they have determined is necessary and, subsequently, 
the need to conduct additional surveys the following year. This would 
result in significantly increased costs incurred by the applicant. 
Thus, the restriction suggested by the commenters would not be 
practicable for the applicant to implement. In consideration of 
potential effectiveness of the recommended measure and its 
practicability for the applicant, NMFS has determined that restricting 
survey start-ups to daylight hours when visibility is unimpeded is not 
warranted or practicable in this case.
    Comment 12: The ENGOs recommended that NMFS require monitoring an 
exclusion zone (EZ) for North Atlantic right whales of 1,000 meters 
(m), around each vessel conducting activities with noise levels that 
could result in injury or harassment to this species.
    Response: Regarding the recommendation for a 1,000 m EZ 
specifically for North Atlantic right whales, we have determined that 
the 500-m EZ, as required in the IHA, is sufficiently protective. We 
note that the 500-m EZ exceeds the modeled distance to the largest 
Level B harassment isopleth distance (141 m) by a substantial margin. 
Thus, we are not requiring shutdown if a right whale is observed beyond 
500-m.
    Comment 13: The ENGOs recommended that a minimum of four PSOs 
should be required, following a two-on/two-off rotation, each 
responsible for scanning no more than 180[deg] of the exclusion zone at 
any given time.
    Response: NMFS does not agree with the commenters that a minimum of 
four PSOs should be required, following a two-on/two-off rotation, to 
meet the MMPA requirement that mitigation must effect the least 
practicable adverse impact upon the affected species or stocks and 
their habitat. Previous IHAs issued for HRG surveys have required that 
a single PSO must be stationed at the highest vantage point and engaged 
in general 360-degree scanning during daylight hours. The monitoring 
reports submitted to NMFS have demonstrated that the PSOs are able to 
detect marine mammals and implement appropriate mitigation measures, 
and project proponents have not exceeded take limits or reported 
unauthorized taking.
    Comment 14: The ENGOs recommended that a combination of visual 
monitoring by PSOs and passive acoustic monitoring (PAM) should be used 
at all times that survey work is underway at noise levels that could 
injure or harm North Atlantic right whales.
    Response: There are several reasons why we do not agree that use of 
PAM is warranted for 24-hour HRG surveys such as the one planned by 
Mayflower. While NMFS agrees that PAM can be an important tool for 
augmenting detection capabilities in certain circumstances, its utility 
in further reducing impact for Mayflower's planned HRG survey 
activities is limited. First, for this activity, the area expected to 
be ensonified above the Level B harassment threshold is relatively 
small (a maximum of 141 m as described in the Estimated Take section)--
this reflects the fact that, to start with, the source level is 
comparatively low and the intensity of any resulting impacts would be 
lower level and, further, it means that inasmuch as PAM will only 
detect a portion of any animals exposed within a zone (see below), the 
overall probability of PAM detecting an animal in the harassment zone 
is low--together these factors support the limited value of PAM for use 
in reducing take with smaller zones. PAM is only capable of detecting 
animals that are actively vocalizing, while many marine mammal species 
vocalize infrequently or during certain activities, which means that 
only a subset of the animals within the range of the PAM would be 
detected (and potentially have reduced impacts). Additionally, 
localization and range detection can be challenging under certain 
scenarios. For example, odontocetes are fast moving and often travel in 
large or dispersed groups which makes localization difficult. In 
addition, the ability of PAM to detect baleen whale vocalizations is 
further limited due to being deployed from the stern of a vessel, which 
puts the PAM hydrophones in proximity to propeller noise and low 
frequency engine noise which can mask the low frequency sounds emitted 
by baleen whales, including right whales.
    We also note that the effects to North Atlantic right whales, and 
all marine mammals, from the types of surveys authorized in this IHA 
are expected to be limited to low level behavioral harassment even in 
the absence of mitigation; no injury is expected or authorized. In 
consideration of the limited additional benefit anticipated by adding 
this detection method (especially for right whales and other low 
frequency cetaceans, species for which PAM has limited efficacy) and 
the cost and impracticability of implementing a full-time PAM program, 
we have determined the current requirements for visual monitoring are 
sufficient to ensure the least practicable adverse impact on the 
affected species or stocks and their habitat. However, we note that 
Mayflower will voluntarily implement PAM during night operations as an 
added precautionary measure even though this is not a NMFS requirement.
    Comment 15: The ENGOs recommended that NMFS require developers to 
select SBP systems and operate those systems at power settings that 
achieve the lowest practicable source level for the objective.
    Response: Mayflower has selected the equipment necessary to achieve 
their objectives. We have evaluated the sound produced by their 
equipment, and made the necessary findings to authorize taking of 
marine mammals incidental to Mayflower's survey activities.
    Comment 16: The ENGOs recommended a requirement that all project 
vessels (regardless of size) operating within the Project Area observe 
a mandatory 10 knot speed restriction during the entire survey period. 
The commenters also recommend that if survey activities are delayed 
into the fall and winter, all project vessels either transiting to/from 
or operating within the Project Area must observe a 10 knot (18.5 
kilometer (km)/hour) speed restriction between November 1, 2020 and 
April 30, 2021.
    Response: NMFS has analyzed the potential for ship strike resulting 
from Mayflower's activity and has determined that the mitigation 
measures specific to ship strike avoidance are sufficient to avoid the 
potential for ship strike. These include: A requirement that all vessel 
operators comply with 10 knot (18.5 km/hour) or less speed restrictions 
in any established dynamic management area (DMA); a requirement that 
all vessel operators reduce vessel speed to 10 knots (18.5 km/hour) or 
less when any large whale, any mother/calf pairs, pods, or large 
assemblages of non-delphinoid cetaceans are observed within 100 m of an 
underway vessel; a requirement that all survey vessels maintain a 
separation distance of 500-m or greater from any sighted North Atlantic 
right whale; a requirement that, if underway, vessels must steer a 
course

[[Page 45582]]

away from any sighted North Atlantic right whale at 10 knots or less 
until the 500-m minimum separation distance has been established; and a 
requirement that, if a North Atlantic right whale is sighted in a 
vessel's path, or within 500 m of an underway vessel, the underway 
vessel must reduce speed and shift the engine to neutral. We have 
determined that the ship strike avoidance measures are sufficient to 
ensure the least practicable adverse impact on species or stocks and 
their habitat. As noted previously, occurrence of vessel strike during 
surveys is extremely unlikely based on the low vessel speed of 
approximately 3 knots (5.6 km/hour) while transiting survey lines. 
Furthermore, no documented vessel strikes have occurred for any HRG 
surveys which were issued IHAs from NMFS.
    Comment 17: The ENGOs objected to NMFS' process to consider 
extending any one-year IHA with a truncated 15-day comment period as 
contrary to the MMPA.
    Response: NMFS' IHA Renewal process meets all statutory 
requirements. All IHAs issued, whether an initial IHA or a Renewal IHA, 
are valid for a period of not more than one year. In addition, the 
public has at least 30 days to comment on all proposed IHAs, with a 
cumulative total of 45 days for IHA Renewals. As noted above, the 
Request for Public Comments section made clear that the agency was 
seeking comment on both the initial proposed IHA and the potential 
issuance of a Renewal for this project. Because any Renewal (as 
explained in the Request for Public Comments section) is limited to 
another year of identical or nearly identical activities in the same 
location (as described in the Description of Proposed Activity section) 
or the same activities that were not completed within the one-year 
period of the initial IHA, reviewers have the information needed to 
effectively comment on both the immediate proposed IHA and a possible 
one-year Renewal, should the IHA holder choose to request one in the 
coming months.
    While there will be additional documents submitted with a Renewal 
request, for a qualifying Renewal these will be limited to 
documentation that NMFS will make available and use to verify that the 
activities are identical to those in the initial IHA, are nearly 
identical such that the changes would have either no effect on impacts 
to marine mammals or decrease those impacts, or are a subset of 
activities already analyzed and authorized but not completed under the 
initial IHA. NMFS will also confirm, among other things, that the 
activities will occur in the same location; involve the same species 
and stocks; provide for continuation of the same mitigation, 
monitoring, and reporting requirements; and that no new information has 
been received that would alter the prior analysis. The Renewal request 
will also contain a preliminary monitoring report, but that is to 
verify that effects from the activities do not indicate impacts of a 
scale or nature not previously analyzed. The additional 15-day public 
comment period provides the public an opportunity to review these few 
documents, provide any additional pertinent information and comment on 
whether they think the criteria for a Renewal have been met. Between 
the initial 30-day comment period on these same activities and the 
additional 15 days, the total comment period for a Renewal is 45 days.
    In addition to the IHA Renewal process being consistent with all 
requirements under section 101(a)(5)(D), it is also consistent with 
Congress' intent for issuance of IHAs to the extent reflected in 
statements in the legislative history of the MMPA. Through the 
provision for Renewals in the regulations, description of the process 
and express invitation to comment on specific potential Renewals in the 
Request for Public Comments section of each proposed IHA, the 
description of the process on NMFS' website, further elaboration on the 
process through responses to comments such as these, posting of 
substantive documents on the agency's website, and provision of 30 or 
45 days for public review and comment on all proposed initial IHAs and 
Renewals respectively, NMFS has ensured that the public ``is invited 
and encouraged to participate fully in the agency decision-making 
process.''
    Comment 18: The ENGOs suggested that it should be NMFS' top 
priority to consider any initial data from state monitoring efforts, 
passive acoustic monitoring data, opportunistic marine mammal sightings 
data, satellite telemetry, and other data sources, because the models 
used by NMFS do not adequately capture increased use of the survey 
areas by right whales. Further, these commenters state that the density 
models NMFS uses result in an underestimate of take, and NMFS should 
take steps now to develop a dataset that more accurately reflects 
marine mammal presence so that it is in hand for future IHA 
authorizations and other work.
    Response: NMFS will review any recommended data sources and will 
continue to use the best available information. We welcome future input 
from interested parties on data sources that may be of use in analyzing 
the potential presence and movement patterns of marine mammals, 
including North Atlantic right whales, in New England waters. NMFS will 
review any recommended data sources and will continue to use the best 
available information. NMFS has used the best available scientific 
information--in this case the marine mammal density models developed by 
the Duke Marine Geospatial Ecology Lab (MGEL) (Roberts et al. 2016, 
2017, 2018)--to inform our determinations. While the ENGOs are correct 
in their statement that North Atlantic right whale distribution has 
shifted in recent years and sightings databases, passive acoustic 
monitoring, and satellite telemetry data may provide additional 
information on right whale presence in the Project Area, no references 
were provided to support any change in density estimates or estimated 
take for North Atlantic right whales. Therefore, NMFS has not made any 
changes to the density information or estimated take presented in the 
Federal Register notice of proposed IHA.
    Comment 19: The ENGOs commented that NMFS should analyze the 
cumulative impacts from Mayflower's survey activities, and other survey 
activities, on North Atlantic right whales and other protected species.
    Response: The MMPA grants exceptions to its broad take prohibition 
for a ``specified activity.'' 16 U.S.C. 1371(a)(5)(A)(i). Cumulative 
impacts (also referred to as cumulative effects) is a term that appears 
in the context of NEPA and the ESA, but it is defined differently in 
those contexts. Neither the MMPA nor NMFS' codified implementing 
regulations address consideration of other unrelated activities and 
their impacts on populations. However, the preamble for NMFS' 
implementing regulations (54 FR 40338; September 29, 1989) states in 
response to comments that the impacts from other past and ongoing 
anthropogenic activities are to be incorporated into the negligible 
impact analysis via their impacts on the baseline. Accordingly, NMFS 
here has factored into its negligible impact analyses the impacts of 
other past and ongoing anthropogenic activities via their impacts on 
the baseline (e.g., as reflected in the density/distribution and status 
of the species, population size and growth rate, and other relevant 
stressors).

Changes From the Proposed IHA to Final IHA

    The estimated take in the proposed IHA was based on monthly density

[[Page 45583]]

estimates and the expected months of survey operations (June through 
September). The survey timing has shifted and surveys are now expected 
to occur from July through September. Mayflower plans to conduct the 
same number of survey days, but rather than averaging the survey 
duration over four months, it has been averaged over three months. 
Estimated take has been recalculated by excluding density estimates for 
the month of June. By shifting the expected survey effort in June to 
the July-September period, the estimated takes for most species either 
decreased or remained the same. This is because the expected June 
densities of most species are higher than densities during the July-
September period. However, for bottlenose dolphins (Tursiops truncatus) 
and common dolphins (Delphinus delphis), the densities during July-
September are somewhat higher than those during June, so the take 
estimates for those two species increased. For bottlenose dolphins, the 
estimated take by Level B harassment increased from 739 to 812 and for 
common dolphins, the estimated take by Level B harassment increased 
from 278 to 318. As a conservative approach, NMFS has authorized the 
higher estimated take from these two calculations.
    In the proposed IHA, NMFS included an exclusion zone of 100-m for 
all marine mammal species other than North Atlantic right whales, which 
required a 500-m exclusion zone, and certain genera of dolphins 
(Delphinus, Lagenorhynchus, and Tursiops) that are most likely to 
voluntarily approach the source vessel for purposes of interacting with 
the vessel (e.g., bow riding). We included this small dolphin exception 
because shutdown requirements for small dolphins represent 
practicability concerns without likely commensurate benefits for the 
animals in question. Small dolphins are typically the most commonly 
observed marine mammals in the specific geographic region and would 
typically be the only marine mammals likely to intentionally approach 
the vessel. However, since the proposed IHA was published in the 
Federal Register on May 27, 2020 (85 FR 31856), Mayflower has been 
conducting geotechnical surveys in the Project Area and has reported 
numerous gray seals (Halichoerus grypus) and harbor seals (Phoca 
vitulina) voluntarily approaching the vessels, within 100 m. Mayflower 
expects that similar conditions may occur during the planned HRG 
surveys, which would result in additional shutdowns. The potential for 
increased shutdowns resulting from pinnipeds approaching within 100 m 
would require the survey vessel to revisit the missed track line to 
reacquire data, resulting in an overall increase in the total sound 
energy input to the marine environment and an increase in the total 
duration over which the survey is active in a given area. Removing the 
100-m exclusion zone for pinnipeds would reduce the operational burden 
on Mayflower, and as described below in the Estimated Take section, 
even absent mitigation, NMFS does not expect that auditory injury is 
likely to occur to any marine mammal species. NMFS concurs that there 
is no meaningful benefit to retaining the 100-m exclusion zone for 
pinnipeds, and has changed the mitigation requirements to include 
pinnipeds in the shutdown exemption for animals that intentionally 
approach the vessel. Pinnipeds that enter the Level B harassment zone 
will be recorded as Level B takes. No changes have been made to the 
number of seals expected to be taken by Level B harassment.

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 2 lists all species or stocks for which take is expected and 
authorized for this action, and summarizes information related to the 
population or stock, including regulatory status under the MMPA and ESA 
and potential biological removal (PBR), where known. For taxonomy, we 
follow Committee on Taxonomy (2019). 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 survey 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 2 are the most 
recent available at the time of publication and are available in the 
2018 Atlantic and Gulf of Mexico Marine Mammal Stock Assessments (Hayes 
et al., 2019a), available online at: www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region 
or and draft 2019 Atlantic and Gulf of Mexico Marine Mammal Stock 
Assessments (Hayes et al. 2019b) available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/draft-marine-mammal-stock-assessment-reports.

                     Table 2--Marine Mammals Known To Occur in the Project Area That May Be Affected by Mayflower's Planned Activity
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                  ESA/MMPA       Stock abundance
                                                                                   status;       (CV, Nmin, most       Predicted               Annual M/
           Common name                Scientific name            Stock          strategic (Y/    recent abundance    abundance \3\   PBR \4\     SI \4\
                                                                                   N) \1\          survey) \2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Balaenidae:
    North Atlantic right whale...  Eubalaena glacialis.  Western North         E/D; Y          428 (0; 418; n/a)..    * 535 (0.45)        0.9       5.56
                                                          Atlantic.

[[Page 45584]]

 
Family Balaenopteridae
 (rorquals):
    Humpback whale...............  Megaptera             Gulf of Maine.......  -/-; N          1,396 (0; 1,380;     * 1,637 (0.07)         22      12.15
                                    novaeangliae.                                               See SAR).
    Fin whale....................  Balaenoptera          Western North         E/D; Y          7,418 (0.25; 6,029;    4,633 (0.08)         12       2.35
                                    physalus.             Atlantic.                             See SAR).
    Sei whale....................  Balaenoptera          Nova Scotia.........  E/D; Y          6292 (1.015; 3,098;    * 717 (0.30)        6.2          1
                                    borealis.                                                   see SAR)236.
    Minke whale..................  Balaenoptera          Canadian East Coast.  -/-; N          24,202 (0.3;         * 2,112 (0.05)      1,189          8
                                    acutorostrata.                                              18,902; See SAR).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Physeteridae:
    Sperm whale..................  Physeter              NA..................  E; Y            4349 (0.28;3,451;      5,353 (0.12)        6.9          0
                                    macrocephalus.                                              See SAR).
Family Delphinidae:
    Long-finned pilot whale......  Globicephala melas..  Western North         -/-; Y          5,636 (0.63; 3,464)      \5\ 18,977         35         38
                                                          Atlantic.                                                         (0.11)
    Bottlenose dolphin...........  Tursiops spp........  Western North         -/-; N          62,851 (0.23;            \5\ 97,476        591         28
                                                          Atlantic Offshore.                    51,914; See SAR).           (0.06)
    Common dolphin...............  Delphinus delphis...  Western North         -/-; N          172,825 (0.21;        86,098 (0.12)      1,452        419
                                                          Atlantic.                             145,216; See SAR).
    Atlantic white-sided dolphin.  Lagenorhynchus        Western North         -/-; N          92,233 (0.71;         37,180 (0.07)        544         26
                                    acutus.               Atlantic.                             54,433; See SAR).
    Risso's dolphin..............  Grampus griseus.....  Western North         -/-; N          35,493 (0.19;          7,732 (0.09)        303       54.3
                                                          Atlantic.                             30,289; See SAR).
Family Phocoenidae (porpoises):
    Harbor porpoise..............  Phocoena phocoena...  Gulf of Maine/Bay of  -/-; N          95,543 (0.31;              * 45,089        851        217
                                                          Fundy.                                74,034; See SAR).           (0.12)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Phocidae (earless seals):
    Gray seal \6\................  Halichoerus grypus..  Western North         -/-; N          27,131 (0.19;                   N/A      1,389      5,688
                                                          Atlantic.                             23,158, 2016).
    Harbor seal..................  Phoca vitulina......  Western North         -/-; N          75,834 (0.15;                   N/A        345        333
                                                          Atlantic.                             66,884, 2018).
--------------------------------------------------------------------------------------------------------------------------------------------------------
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--This information represents species- or guild-specific abundance predicted by recent habitat-based cetacean density models (Roberts et al., 2016,
  2017, 2018). These models provide the best available scientific information regarding predicted density patterns of cetaceans in the U.S. Atlantic
  Ocean, and we provide the corresponding abundance predictions as a point of reference. Total abundance estimates were produced by computing the mean
  density of all pixels in the modeled area and multiplying by its area. For those species marked with an asterisk, the available information supported
  development of either two or four seasonal models; each model has an associated abundance prediction. Here, we report the maximum predicted abundance.
4--Potential biological removal, defined by the MMPA as the maximum number of animals, not including natural mortalities, that may be removed from a
  marine mammal stock while allowing that stock to reach or maintain its optimum sustainable population size (OSP). Annual M/SI, found in NMFS' 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. All M/SI values are as presented
  in the draft 2019 SARs (Hayes et al., 2019).
5--Abundance estimates are in some cases reported for a guild or group of species when those species are difficult to differentiate at sea. Similarly,
  the habitat-based cetacean density models produced by Roberts et al. (2016, 2017, 2018) are based in part on available observational data which, in
  some cases, is limited to genus or guild in terms of taxonomic definition. Roberts et al. (2016, 2017, 2018) produced density models to genus level
  for Globicephala spp. and produced a density model for bottlenose dolphins that does not differentiate between offshore and coastal stocks.
6--8 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 2 temporally and spatially co-occur with the activity to the 
degree that take is reasonably likely to occur, and we have authorized 
it. All species that could potentially occur in the planned survey 
areas are included in Table 4 of the IHA application. However, the 
temporal and/or spatial occurrence of several species listed in Table 4 
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., 2019b). 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 
planned survey dates (Hayes et al., 2019b). As take of these species is 
not anticipated as a result of the planned activities, these species 
are not analyzed further.
    A detailed description of the species for which take has been 
authorized,

[[Page 45585]]

including brief introductions to the relevant stocks as well as 
available information regarding population trends and threats, and 
information regarding local occurrence, were provided in the Federal 
Register notice for the proposed IHA (85 FR 31856; May 27, 2020); since 
that time, we are not aware of any changes in the status of these 
species and stocks; therefore, detailed descriptions are not provided 
here. Please refer to that Federal Register notice for these 
descriptions. Please also refer to NMFS' website (https://www.fisheries.noaa.gov/find-species) for generalized species accounts.

Potential Effects of Specified Activities on Marine Mammals and their 
Habitat

    The effects of underwater noise from Mayflower's survey activities 
have the potential to result in take of marine mammals by harassment in 
the vicinity of the survey area. The Federal Register notice for the 
proposed IHA (85 FR 31856; May 27, 2020) included a discussion of the 
effects of anthropogenic noise on marine mammals and their habitat. 
That information and analysis is incorporated by reference into this 
final IHA determination and is not repeated here; please refer to the 
notice of proposed IHA (85 FR 31856; May 27, 2020).

Estimated Take

    This section provides an estimate of the number of incidental takes 
authorized 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 the Mitigation section, Level A harassment is neither 
anticipated nor authorized.
    As described previously, no mortality is anticipated or authorized 
for this activity. Below we describe how the take is estimated.
    Generally speaking, we estimate take by considering: (1) Acoustic 
thresholds above which NMFS believes the best available science 
indicates marine mammals will be behaviorally harassed or incur some 
degree of permanent hearing impairment; (2) the area or volume of water 
that will be ensonified above these levels in a day; (3) the density or 
occurrence of marine mammals within these ensonified areas; and, (4) 
and the number of days of activities. We note that while these basic 
factors can contribute to a basic calculation to provide an initial 
prediction of takes, additional information that can qualitatively 
inform take estimates is also sometimes available (e.g., previous 
monitoring results or average group size). Below, we describe the 
factors considered here in more detail and present the authorized take.

Acoustic Thresholds

    Using the best available science, NMFS has developed 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 we consider Level B 
harassment when exposed to underwater anthropogenic noise above 
received levels of 160 decibels (dB) re 1 microPascal ([mu]Pa) (root 
mean square (rms)) for impulsive and/or intermittent sources (e.g., 
impact pile driving) and 120 dB rms for continuous sources (e.g., 
vibratory driving). Mayflower's planned activity includes the use of 
impulsive sources (geophysical survey equipment), and therefore use of 
the 160 dB re 1 [mu]Pa (rms) threshold is applicable.
    Level A harassment for non-explosive sources--NMFS' Technical 
Guidance for Assessing the Effects of Anthropogenic Sound on Marine 
Mammal Hearing (Version 2.0) (Technical Guidance, 2018) identifies dual 
criteria to assess auditory injury (Level A harassment) to five 
different marine mammal groups (based on hearing sensitivity) as a 
result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). The components of Mayflower's planned 
activity includes the use of 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 sounds (such as HRG survey 
equipment) contained in the Technical Guidance (NMFS, 2018) were 
presented as dual metric acoustic thresholds using both cumulative 
sound exposure level (SELcum) and peak sound pressure level 
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 3 below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS 2018 Technical Guidance, which may be accessed at: 
www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

[[Page 45586]]



                     Table 3--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                    PTS Onset acoustic thresholds * (received level)
             Hearing group             -------------------------------------------------------------------------
                                                Impulsive                          Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans..........  Cell 1: Lpk,flat: 219 dB;  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 [mu]Pa, and cumulative sound exposure level (LE) has
  a reference value of 1[mu]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, we describe 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 planned survey entails 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 (NMFS, 
2019). This methodology incorporates frequency and some directionality 
to refine estimated ensonified zones. Mayflower used the methods 
specified in the interim methodology (NMFS, 2019). The Level B 
harassment zone for the Innomar parametric sub-bottom profiler was 
calculated using this methodology, with additional modifications to 
account for energy emitted outside of the primary beam of the source. 
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 B 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. In cases when the source level for a specific 
type of HRG equipment is not provided in Crocker and Fratantonio 
(2016), NMFS recommends that either the source levels provided by the 
manufacturer be used, or, in instances where source levels provided by 
the manufacturer are unavailable or unreliable, a proxy from Crocker 
and Fratantonio (2016) be used instead. Table 1 shows the HRG equipment 
types that may be used during the planned surveys and the sound levels 
associated with those HRG equipment types. Tables 2 and 4 of Appendix B 
in the IHA application shows the literature sources for the sound 
source levels that are shown in Table 1 and that were incorporated into 
the modeling of Level B isopleth distances to the Level B harassment 
threshold.
    Results of modeling using the methodology described above indicated 
that, of the HRG survey equipment planned for use by Mayflower that has 
the potential to result in harassment of marine mammals, sound produced 
by the Geomarine Geo-Spark 400 tip sparker would propagate furthest to 
the Level B harassment threshold (Table 4); therefore, for the purposes 
of the exposure analysis, it was assumed the Geomarine Geo-Spark 400 
tip sparker would be active during the entire duration of the surveys. 
Thus the distance to the isopleth corresponding to the threshold for 
Level B harassment for the Geomarine Geo-Spark 400 tip sparker 
(estimated at 141 m; Table 4) was used as the basis of the take 
calculation for all marine mammals. Note that this results in a 
conservative estimate of the total ensonified area resulting from the 
planned activities as Mayflower may not operate the Geomarine Geo-Spark 
400 tip sparker during the entire planned survey, and for any survey 
segments in which it is not ultimately operated, the distance to the 
Level B harassment threshold would be less than 141 m (Table 4). 
However, as Mayflower cannot predict the precise number of survey days 
that will require the use of the Geomarine Geo-Spark 400 tip sparker, 
it was assumed that it would be operated during the entire duration of 
the planned surveys.

[[Page 45587]]



  Table 4--Modeled Radial Distances From HRG Survey Equipment to Isopleths Corresponding to Level A and Level B
                                              Harassment Thresholds
----------------------------------------------------------------------------------------------------------------
                                       Radial distance to Level A harassment threshold (m) *          Radial
                                 ----------------------------------------------------------------   distance to
                                                                                                      Level B
                                                                                                    harassment
          Sound source             Low frequency   Mid frequency  High frequency      Phocid       Threshold (m)
                                     cetaceans       cetaceans       cetaceans       pinnipeds   ---------------
                                                                                   (underwater)     All marine
                                                                                                      mammals
----------------------------------------------------------------------------------------------------------------
Innomar SES-2000 Medium-100                   <1              <1              60              <1             116
 Parametric.....................
Edgetech 2000-DSS...............              <1              <1               3              <1               5
Geomarine Geo-Spark 400 tip                   <1              <1               8              <1             141
 sparker (800 Joules)...........
----------------------------------------------------------------------------------------------------------------
* Distances to the Level A harassment threshold based on the larger of the dual criteria (peak SPL and SELcum)
  are shown. For all sources the SELcum metric resulted in larger isopleth distances.

    Predicted distances to Level A harassment isopleths, which vary 
based on marine mammal functional hearing groups (Table 3), were also 
calculated. The updated acoustic thresholds for impulsive sounds (such 
as HRG survey equipment) contained in the Technical Guidance (NMFS, 
2018) were presented as dual metric acoustic thresholds using both 
cumulative sound exposure level (SELcum) and peak sound 
pressure level 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., the 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.
    Modeling of distances to isopleths corresponding to the Level A 
harassment threshold was performed for all types of HRG equipment 
planned for use with the potential to result in harassment of marine 
mammals. Mayflower used a new 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.
    We 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 necessarily agree with this step in the 
modeling assessment, which results in nearly all HRG sources being 
classified as impulsive; however, we note that the classification of 
the majority of HRG sources as impulsive results in more conservative 
modeling results. Thus, we have assessed the potential for Level A 
harassment to result from the planned activities based on the modeled 
Level A zones with the acknowledgement that these zones are likely 
conservative.
    Modeled isopleth distances to Level A harassment thresholds for all 
types of HRG equipment and all marine mammal functional hearing groups 
are shown in Table 4. The dual criteria (peak SPL and 
SELcum) were applied to all HRG sources using the modeling 
methodology as described above, and the largest isopleth distances for 
each functional hearing group were then carried forward in the exposure 
analysis to be conservative. For all HRG sources, the SELcum 
metric resulted in larger isopleth distances. Distances to the Level A 
harassment threshold based on the larger of the dual criteria (peak SPL 
and SELcum) are shown in Table 4.
    Modeled distances to isopleths corresponding to the Level A 
harassment threshold are very small (<1 m) for three of the four marine 
mammal functional hearing groups that may be impacted by the planned 
activities (i.e., low frequency and mid frequency cetaceans, and phocid 
pinnipeds; see Table 4). Based on the very 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. For harbor 
porpoises (a high frequency specialist), the largest modeled distance 
to the Level A harassment threshold for the high frequency functional 
hearing group was 60 m (Table 4). However, as noted above, modeled 
distances to isopleths corresponding to the Level A harassment 
threshold are assumed to be conservative. Further, the Innomar source 
uses a very narrow beam width (two degrees) and the distances to the 
Level A harassment isopleths are eight meters or less for the other two 
sources. 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

[[Page 45588]]

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, and 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, we have determined that the potential for take 
by Level A harassment of harbor porpoises is so low as to be 
discountable. As NMFS has determined that the likelihood of take of any 
marine mammals in the form of Level A harassment occurring as a result 
of the planned surveys is so low as to be discountable, we therefore 
have not authorized the take by Level A harassment of any marine 
mammals.

Marine Mammal Occurrence

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations.
    The habitat-based density models produced by the Duke University 
Marine Geospatial Ecology Laboratory (Roberts et al., 2016, 2017, 2018) 
represent the best available information regarding marine mammal 
densities in the planned survey area. The density data presented by 
Roberts et al. (2016, 2017, 2018) incorporates aerial and shipboard 
line-transect survey data from NMFS and other organizations and 
incorporates data from 8 physiographic and 16 dynamic oceanographic and 
biological covariates, and controls for the influence of sea state, 
group size, availability bias, and perception bias on the probability 
of making a sighting. These density models were originally developed 
for all cetacean taxa in the U.S. Atlantic (Roberts et al., 2016). In 
subsequent years, certain models have been updated on the basis of 
additional data as well as certain methodological improvements. Our 
evaluation of the changes leads to a conclusion that these represent 
the best scientific evidence available. More information, including the 
model results and supplementary information for each model, is 
available online at seamap.env.duke.edu/models/Duke-EC-GOM-2015/. 
Marine mammal density estimates in the project area (animals/km\2\) 
were obtained using these model results (Roberts et al., 2016, 2017, 
2018). The updated models incorporate additional sighting data, 
including sightings from the NOAA Atlantic Marine Assessment Program 
for Protected Species (AMAPPS) surveys from 2010-2014 (NEFSC & SEFSC, 
2011, 2012, 2014a, 2014b, 2015, 2016).
    For the exposure analysis, density data from Roberts et al. (2016, 
2017, 2018) were mapped using a geographic information system (GIS). 
These data provide abundance estimates for species or species guilds 
within 10 km x 10 km grid cells (100 km\2\) on a monthly or annual 
basis, depending on the species. In order to select a representative 
sample of grid cells in and near the Project Area, a 10-km wide 
perimeter around the Lease Area and an 8-km wide perimeter around the 
cable route were created in GIS (ESRI 2017). The perimeters were then 
used to select grid cells near the Project Area containing the most 
recent monthly or annual estimates for each species in the Roberts et 
al. (2016, 2017, 2018) data. The average monthly abundance for each 
species in each survey area (deep-water and shallow-water) was 
calculated as the mean value of the grid cells within each survey 
portion in each month (July through September), and then converted for 
density (individuals/km\2\) by dividing by 100 km\2\ (Tables 5 and 6).
    Roberts et al. (2018) produced density models for all seals and did 
not differentiate by seal species. Because the seasonality and habitat 
use by gray seals roughly overlaps with that of harbor seals in the 
survey areas, it was assumed that modeled takes of seals could occur to 
either of the respective species, thus the total number of modeled 
takes for seals was applied to each species.

   Table 5--Average Monthly Densities for Species in the Lease Area and Deep-Water Section of the Cable Route
----------------------------------------------------------------------------------------------------------------
                                                                   Estimated monthly density (individuals/km\2\)
                             Species                             -----------------------------------------------
                                                                       July           August         September
----------------------------------------------------------------------------------------------------------------
Fin whale.......................................................          0.0033          0.0029          0.0025
Humpback whale..................................................          0.0011          0.0005          0.0011
Minke whale.....................................................          0.0010          0.0007          0.0008
North Atlantic right whale......................................          0.0000          0.0000          0.0000
Sei whale.......................................................          0.0001          0.0000          0.0001
Atlantic white-sided dolphin....................................          0.0446          0.0243          0.0246
Bottlenose dolphin..............................................          0.0516          0.0396          0.0494
Harbor porpoise.................................................          0.0125          0.0114          0.0093
Pilot whale.....................................................          0.0066          0.0066          0.0066
Risso's dolphin.................................................          0.0005          0.0009          0.0007
Common dolphin..................................................          0.0614          0.1069          0.1711
Sperm whale.....................................................          0.0004          0.0004          0.0002
Seals (harbor and gray).........................................          0.0061          0.0033          0.0040
----------------------------------------------------------------------------------------------------------------


         Table 6--Average Monthly Densities for Species in the Shallow-Water Section of the Cable Route
----------------------------------------------------------------------------------------------------------------
                                                                   Estimated monthly density (individuals/km\2\)
                             Species                             -----------------------------------------------
                                                                       July           August         September
----------------------------------------------------------------------------------------------------------------
Fin whale.......................................................          0.0003          0.0003          0.0003
Humpback whale..................................................          0.0001          0.0000          0.0001
Minke whale.....................................................          0.0000          0.0000          0.0000
North Atlantic right whale......................................          0.0000          0.0000          0.0000
Sei whale.......................................................          0.0000          0.0000          0.0000
Atlantic white-sided dolphin....................................          0.0006          0.0005          0.0008

[[Page 45589]]

 
Bottlenose dolphin..............................................          0.4199          0.3211          0.3077
Harbor porpoise.................................................          0.0023          0.0037          0.0036
Pilot whale.....................................................          0.0000          0.0000          0.0000
Risso's dolphin.................................................          0.0000          0.0000          0.0000
Common dolphin..................................................          0.0002          0.0006          0.0009
Sperm whale.....................................................          0.0000          0.0000          0.0000
Seals (harbor and gray).........................................          0.0281          0.0120          0.0245
----------------------------------------------------------------------------------------------------------------

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate.
    In order to estimate the number of marine mammals predicted to be 
exposed to sound levels that would result in harassment, radial 
distances to predicted isopleths corresponding to harassment thresholds 
are calculated, as described above. Those distances are then used to 
calculate the area(s) around the HRG survey equipment predicted to be 
ensonified to sound levels that exceed harassment thresholds. The area 
estimated to be ensonified to relevant thresholds in a single day is 
then calculated, based on areas predicted to be ensonified around the 
HRG survey equipment and the estimated trackline distance traveled per 
day by the survey vessel. Mayflower estimates that the survey vessel in 
the Lease Area and deep-water sections of the cable route will achieve 
a maximum daily trackline of 110 km per day and the survey vessels in 
the shallow-water section of the cable route will achieve a maximum of 
55 km per day during planned HRG surveys. This distance accounts for 
survey vessels traveling at roughly 3 knots and accounts for non-active 
survey periods.
    Based on the maximum estimated distance to the Level B harassment 
threshold of 141 m (Table 4) and the maximum estimated daily track line 
distance of 110 km, an area of 31.1 km\2\ would be ensonified to the 
Level B harassment threshold each day in the Lease Area and deep-water 
section of the cable route during Mayflower's planned surveys. During 
90 days of anticipated survey activity over the three month period 
(July through September), approximately 30 days of survey activity are 
expected each month, for an average of 933 km\2\ ensonified to the 
Level B harassment threshold in the Lease Area and deep-water section 
of the cable route each month of survey activities.
    Similarly, based on the maximum estimated distance to the Level B 
harassment threshold of 141 m (Table 4) and the maximum estimated daily 
track line distance of 55 km, an area of 15.6 km\2\ would be ensonified 
to the Level B harassment threshold each day in the shallow-water 
section of the cable route. During 125 days of anticipated survey 
activity over the three month period (July through September), 
approximately 41.7 days of survey activity (split among two vessels) 
are expected each month, for an average of 650 km\2\ ensonified to the 
Level B harassment threshold in the shallow-water section of the cable 
route each month of survey activities.
    As described above, this is a conservative estimate as it assumes 
the HRG sources that result in the greatest isopleth distances to the 
Level B harassment threshold would be operated at all times during all 
215 vessel days.
    The estimated numbers of marine mammals that may be taken by Level 
B harassment were calculated by multiplying the monthly density for 
each species in each survey area (Tables 5 and 6) by the respective 
monthly ensonified area within each survey section. The results were 
then summed to determine the total estimated take (Table 7).

                     Table 7--Total Numbers of Authorized Incidental Takes of Marine Mammals and Takes as a Percentage of Population
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Calculated take by survey                                                         Total
                                                                      region                                                                authorized
                                                         --------------------------------      Total        Authorized      Authorized     instances of
                         Species                                                            calculated    takes by Level  takes by Level     take as a
                                                          Lease area and  Shallow- water  takes by Level   A harassment   B harassment b   percentage of
                                                            deep- water     cable route    B harassment                                    population a
                                                            cable route
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fin whale...............................................             8.3             0.6             8.9               0               9             0.3
Humpback whale..........................................             2.9             0.2             3.1               0               4             0.2
Minke whale.............................................             3.4             0.2             3.6               0               4             0.1
North Atlantic right whale..............................             0.9               0             0.9               0             c 3             0.8
Sei whale...............................................             0.3               0             0.3               0             c 2             0.4
Atlantic white-sided dolphin............................           109.3             1.4           110.7               0             111             0.1
Bottlenose dolphin......................................           131.0           680.4           811.5               0             812             1.0
Harbor porpoise.........................................            36.4               7            43.4               0              44             0.1
Pilot whale.............................................            18.4               0            18.4               0              19             0.1
Risso's dolphin.........................................             1.7               0             1.7               0             b 6             0.1
Common dolphin..........................................           316.5             1.1           317.6               0             318             0.3
Sperm whale.............................................             0.8               0             0.8               0             c 2           <0.01

[[Page 45590]]

 
Seals (harbor and gray).................................            40.4           152.8           193.2               0             194             0.7
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Calculations of percentage of stock taken are based on the best available abundance estimate as shown in Table 2. In most cases the best available
  abundance estimate is provided by Roberts et al. (2016, 2017, 2018), when available, to maintain consistency with density estimates derived from
  Roberts et al. (2016, 2017, 2018). For bottlenose dolphins and seals, Roberts et al. (2016, 2017, 2018) provides only a single abundance estimate and
  does not provide abundance estimates at the stock or species level (respectively), so the abundance estimate used to estimate percentage of stock
  taken for bottlenose dolphins is derived from NMFS SARs (Hayes et al., 2019). For seals, NMFS proposes to authorize 194 takes of seals as a guild by
  Level B harassment and assumes take could occur to either species. For the purposes of estimating percentage of stock taken, the NMFS SARs abundance
  estimate for gray seals was used as the abundance of gray seals is lower than that of harbor seals (Hayes et al., 2019).
\b\ Authorized take equal to calculated take rounded up to next integer, or mean group size.
\c\ Authorized take increased to mean group size (Palka et al., 2017; Kraus et al., 2016).

    Using the take methodology approach described above, the take 
estimates for Risso's dolphin, sei whale, North Atlantic right whale, 
and sperm whale were less than the average group sizes estimated for 
these species (Table 7). However, information on the social structures 
of these species indicates these species are likely to be encountered 
in groups. Therefore it is reasonable to conservatively assume that one 
group of each of these species will be taken during the planned survey. 
We have therefore authorized the take of the average group size for 
these species to account for the possibility that the planned survey 
encounters a group of either of these species (Table 7).
    As described above, NMFS has determined that the likelihood of take 
of any marine mammals in the form of Level A harassment occurring as a 
result of the planned surveys is so low as to be discountable; 
therefore, we have not authorized take of any marine mammals by Level A 
harassment.

Mitigation

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

Mitigation Measures

    NMFS has required the following mitigation measures be implemented 
during Mayflower's planned marine site characterization surveys.

Marine Mammal Exclusion Zones, Buffer Zone and Monitoring Zone

    Marine mammal exclusion zones (EZ) must be established around the 
HRG survey equipment and monitored by protected species observers (PSO) 
during HRG surveys as follows:
     A 500-m EZ is required for North Atlantic right whales; 
and
     A 100-m EZ is required for all other marine mammals (with 
the exception of certain small dolphin species and pinnipeds specified 
below).
    If a marine mammal is detected approaching or entering the EZs 
during the planned survey, the vessel operator must adhere to the 
shutdown procedures described below. In addition to the EZs described 
above, PSOs must visually monitor a 200 m Buffer Zone. During use of 
acoustic sources with the potential to result in marine mammal 
harassment (i.e., anytime the acoustic source is active, including 
ramp-up), occurrences of marine mammals within the Buffer Zone (but 
outside the EZs) must be communicated to the vessel operator to prepare 
for potential shutdown of the acoustic source. The Buffer Zone is not 
applicable when the EZ is greater than 100 meters. PSOs are also 
required to observe a 500-m Monitoring Zone and record the presence of 
all marine mammals within this zone. In addition, any marine mammals 
observed within 141 m of the active HRG equipment operating at or below 
180 kHz must be documented by PSOs as taken by Level B harassment. The 
zones described above must be based upon the radial distance from the 
active equipment (rather than being based on distance from the vessel 
itself).

Visual Monitoring

    A minimum of one NMFS-approved PSO must be on duty and conducting 
visual observations at all times during daylight hours (i.e., from 30 
minutes prior to sunrise through 30 minutes following sunset) and 30 
minutes prior to and during nighttime ramp-ups of HRG equipment. Visual 
monitoring

[[Page 45591]]

must begin no less than 30 minutes prior to ramp-up of HRG equipment 
and must continue until 30 minutes after use of the acoustic source 
ceases or until 30 minutes past sunset. PSOs must establish and monitor 
the applicable EZs, Buffer Zone and Monitoring Zone as described above. 
Visual PSOs must coordinate to ensure 360[deg] visual coverage around 
the vessel from the most appropriate observation posts, and must 
conduct visual observations using binoculars and the naked eye while 
free from distractions and in a consistent, systematic, and diligent 
manner. PSOs must estimate distances to marine mammals located in 
proximity to the vessel and/or relevant using range finders. It is the 
responsibility of the Lead PSO on duty to communicate the presence of 
marine mammals as well as to communicate and enforce the action(s) that 
are necessary to ensure mitigation and monitoring requirements are 
implemented as appropriate. Position data must be recorded using hand-
held or vessel global positioning system (GPS) units for each confirmed 
marine mammal sighting.

Pre-Clearance of the Exclusion Zones

    Prior to initiating HRG survey activities, Mayflower must implement 
a 30-minute pre-clearance period. During pre-clearance monitoring 
(i.e., before ramp-up of HRG equipment begins), the Buffer Zone will 
also act as an extension of the 100-m EZ in that observations of marine 
mammals within the 200-m Buffer Zone will also preclude HRG operations 
from beginning. During this period, PSOs must ensure that no marine 
mammals are observed within 200 m of the survey equipment (500 m in the 
case of North Atlantic right whales). HRG equipment must not start up 
until this 200-m zone (or, 500-m zone in the case of North Atlantic 
right whales) is clear of marine mammals for at least 30 minutes. The 
vessel operator must notify a designated PSO of the planned start of 
HRG survey equipment as agreed upon with the lead PSO; the notification 
time should not be less than 30 minutes prior to the planned initiation 
of HRG equipment order to allow the PSOs time to monitor the EZs and 
Buffer Zone for the 30 minutes of pre-clearance. A PSO conducting pre-
clearance observations must be notified again immediately prior to 
initiating active HRG sources.
    If a marine mammal were observed within the relevant EZs or Buffer 
Zone during the pre-clearance period, initiation of HRG survey 
equipment must not begin until the animal(s) has been observed exiting 
the respective EZ or Buffer Zone, or, until an additional time period 
has elapsed with no further sighting (i.e., minimum 15 minutes for 
small odontocetes and seals, and 30 minutes for all other species). The 
pre-clearance requirement includes small delphinoids that approach the 
vessel (e.g., bow ride). PSOs must also continue to monitor the zone 
for 30 minutes after survey equipment is shut down or survey activity 
has concluded.

Ramp-Up of Survey Equipment

    When technically feasible, a ramp-up procedure must be used for 
geophysical survey equipment capable of adjusting energy levels at the 
start or re-start of survey activities. The ramp-up procedure must 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 detect the presence of the survey and vacate the area 
prior to the commencement of survey equipment operation at full power. 
Ramp-up of the survey equipment must not begin until the relevant EZs 
and Buffer Zone has been cleared by the PSOs, as described above. HRG 
equipment must be initiated at their lowest power output and must be 
incrementally increased to full power. If any marine mammals are 
detected within the EZs or Buffer Zone prior to or during ramp-up, the 
HRG equipment must be shut down (as described below).

Shutdown Procedures

    If an HRG source is active and a marine mammal is observed within 
or entering a relevant EZ (as described above) an immediate shutdown of 
the HRG survey equipment is required. When shutdown is called for by a 
PSO, the acoustic source must be immediately deactivated and any 
dispute resolved only following deactivation. Any PSO on duty has the 
authority to delay the start of survey operations or to call for 
shutdown of the acoustic source if a marine mammal is detected within 
the applicable EZ. The vessel operator must establish and maintain 
clear lines of communication directly between PSOs on duty and crew 
controlling the HRG source(s) to ensure that shutdown commands are 
conveyed swiftly while allowing PSOs to maintain watch. Subsequent 
restart of the HRG equipment must only occur after the marine mammal 
has either been observed exiting the relevant EZ, or, until an 
additional time period has elapsed with no further sighting of the 
animal within the relevant EZ (i.e., 15 minutes for small odontocetes 
and seals, and 30 minutes for large whales).
    Upon implementation of shutdown, the HRG source may be reactivated 
after the marine mammal that triggered the shutdown has been observed 
exiting the applicable EZ (i.e., the animal is not required to fully 
exit the Buffer Zone where applicable) or, following a clearance period 
of 15 minutes for small odontocetes and seals and 30 minutes for all 
other species with no further observation of the marine mammal(s) 
within the relevant EZ. If the HRG equipment shuts down for brief 
periods (i.e., less than 30 minutes) for reasons other than mitigation 
(e.g., mechanical or electronic failure) the equipment may be re-
activated as soon as is practicable at full operational level, without 
30 minutes of pre-clearance, only if PSOs have maintained constant 
visual observation during the shutdown and no visual detections of 
marine mammals occurred within the applicable EZs and Buffer Zone 
during that time. For a shutdown of 30 minutes or longer, or if visual 
observation was not continued diligently during the pause, pre-
clearance observation is required, as described above.
    The shutdown requirement is waived for certain genera of small 
delphinids (i.e., Delphinus, Lagenorhynchus, and Tursiops) and 
pinnipeds (gray and harbor seals) under certain circumstances. If a 
delphinid(s) from these genera or seal(s) is visually detected 
approaching the vessel (i.e., to bow ride) or towed survey equipment, 
shutdown is not required. 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 judgment in making 
the decision to call for a shutdown.
    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 
area encompassing the Level B harassment isopleth (141 m), shutdown 
must occur.

Vessel Strike Avoidance

    Vessel strike avoidance measures include, but are not limited to, 
the following, except under circumstances when complying with these 
requirements would put the safety of the vessel or crew at risk:
     All vessel operators and crew will maintain vigilant watch 
for cetaceans and pinnipeds, and slow down or stop their vessel to 
avoid striking these protected species;
     All survey vessels, regardless of size, must observe a 10-
knot speed

[[Page 45592]]

restriction in DMAs designated by NMFS for the protection of North 
Atlantic right whales from vessel strikes. Note that this requirement 
includes vessels, regardless of size, to adhere to a 10 knot speed 
limit in DMAs, not just vessels 65 ft or greater in length;
     All vessel operators will reduce vessel speed to 10 knots 
(18.5 km/hr) or less when any large whale, any mother/calf pairs, large 
assemblages of non-delphinoid cetaceans are observed near (within 100 m 
(330 ft)) an underway vessel;
     All vessels will maintain a separation distance of 500 m 
(1,640 ft) or greater from any sighted North Atlantic right whale;
     If underway, vessels must steer a course away from any 
sighted North Atlantic right whale at 10 knots (18.5 km/hr) or less 
until the 500-m (1,640 ft) minimum separation distance has been 
established. If a North Atlantic right whale is sighted in a vessel's 
path, or within 100 m (330 ft) to an underway vessel, the underway 
vessel must reduce speed and shift the engine to neutral. Engines will 
not be engaged until the North Atlantic right whale has moved outside 
of the vessel's path and beyond 100 m. If stationary, the vessel must 
not engage engines until the North Atlantic right whale has moved 
beyond 100 m;
     All vessels will maintain a separation distance of 100 m 
(330 ft) or greater from any sighted non-delphinoid cetacean. If 
sighted, the vessel underway must reduce speed and shift the engine to 
neutral, and must not engage the engines until the non-delphinoid 
cetacean has moved outside of the vessel's path and beyond 100 m. If a 
survey vessel is stationary, the vessel will not engage engines until 
the non-delphinoid cetacean has moved out of the vessel's path and 
beyond 100 m;
     All vessels will maintain a separation distance of 50 m 
(164 ft) or greater from any sighted delphinoid cetacean. Any vessel 
underway remain parallel to a sighted delphinoid cetacean's course 
whenever possible, and avoid excessive speed or abrupt changes in 
direction. Any vessel underway reduces vessel speed to 10 knots (18.5 
km/hr) or less when pods (including mother/calf pairs) or large 
assemblages of delphinoid cetaceans are observed. Vessels may not 
adjust course and speed until the delphinoid cetaceans have moved 
beyond 50 m and/or the abeam of the underway vessel;
     All vessels will maintain a separation distance of 50 m 
(164 ft) or greater from any sighted pinniped; and
     All vessels underway will not divert or alter course in 
order to approach any whale, delphinoid cetacean, or pinniped. Any 
vessel underway will avoid excessive speed or abrupt changes in 
direction to avoid injury to the sighted cetacean or pinniped.
    Project-specific training will be conducted for all vessel crew 
prior to the start of survey activities. 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 
members understand and will comply with the necessary requirements 
throughout the survey activities.

Passive Acoustic Monitoring

    Mayflower will also employ passive acoustic monitoring (PAM) to 
support monitoring during night time operations to provide for 
acquisition of species detections at night. While PAM is not typically 
required by NMFS for HRG surveys, it may a provide additional benefit 
as a mitigation and monitoring measure to further limit potential 
exposure to underwater sound at levels that could result in injury or 
behavioral harassment.
    Based on our evaluation of the applicant's planned measures, as 
well as other measures considered by NMFS, NMFS has determined that the 
required mitigation measures provide the means effecting the least 
practicable impact on the affected species or stocks and their habitat, 
paying particular attention to rookeries, mating grounds, and areas of 
similar significance.

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 
planned 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.

Monitoring Measures

    As described above, visual monitoring must be performed by 
qualified and NMFS-approved PSOs. Mayflower must use independent, 
dedicated, trained PSOs, meaning that the PSOs must be employed by a 
third-party observer provider, must 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 must have successfully completed an approved PSO training 
course appropriate for their designated task. Mayflower must provide 
resumes of all proposed PSOs (including alternates) to NMFS for review 
and approval prior to the start of survey operations.
    During 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 and 
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) and nighttime ramp-ups of HRG 
equipment. Visual monitoring must begin no less than 30 minutes prior 
to initiation of HRG survey equipment and

[[Page 45593]]

must continue until one hour after use of the acoustic source ceases or 
until 30 minutes past sunset. PSOs must coordinate to ensure 360[deg] 
visual coverage around the vessel from the most appropriate observation 
posts, and must conduct visual observations using binoculars 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 must be communicated 
to PSOs on all survey vessels.
    PSOs must be equipped with binoculars and have the ability to 
estimate distances to marine mammals located in proximity to the vessel 
and/or exclusion zone using range finders. Reticulated binoculars will 
also be available to PSOs for use as appropriate based on conditions 
and visibility to support the monitoring of marine mammals. Position 
data must be recorded using hand-held or vessel GPS units for each 
sighting. Observations must take place from the highest available 
vantage point on the survey vessel. General 360-degree scanning must 
occur during the monitoring periods, and target scanning by the PSO 
must occur when alerted of a marine mammal presence.
    During good conditions (e.g., daylight hours; Beaufort sea state 
(BSS) 3 or less), to the maximum extent practicable, PSOs must conduct 
observations when the acoustic source is not operating for comparison 
of sighting rates and behavior with and without use of the acoustic 
source and between acquisition periods. Any observations of marine 
mammals by crew members aboard any vessel associated with the survey 
must be relayed to the PSO team.
    Data on all PSO observations must be recorded based on standard PSO 
collection requirements. This includes dates, times, and locations of 
survey operations; dates and times of observations, location and 
weather; details of marine mammal sightings (e.g., species, numbers, 
behavior); and details of any observed marine mammal take that occurs 
(e.g., noted behavioral disturbances).

Reporting Measures

    Within 90 days after completion of survey activities, a final 
technical report must be provided to NMFS that fully documents the 
methods and monitoring protocols, summarizes the data recorded during 
monitoring, summarizes the number of marine mammals estimated to have 
been taken 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.
    In addition to the final technical report, Mayflower must provide 
the reports described below as necessary during survey activities. In 
the unanticipated event that Mayflower's activities lead to an injury 
(Level A harassment) of a marine mammal, Mayflower must immediately 
cease the specified activities and report the incident to the NMFS 
Office of Protected Resources Permits and Conservation Division and the 
NMFS Northeast Regional Stranding Coordinator. The report must include 
the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Name and type of vessel involved;
     Vessel's speed during and leading up to the incident;
     Description of the incident;
     Status of all sound source use in the 24 hours preceding 
the incident;
     Water depth;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
     Description of all marine mammal observations in the 24 
hours preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).
    Activities must not resume until NMFS is able to review the 
circumstances of the event. NMFS will work with Mayflower to minimize 
reoccurrence of such an event in the future. Mayflower must not resume 
activities until notified by NMFS.
    In the event that Mayflower personnel discover an injured or dead 
marine mammal, Mayflower must report the incident to the OPR Permits 
and Conservation Division and the NMFS Northeast Regional Stranding 
Coordinator as soon as feasible. The report must include the following 
information:
     Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
     Species identification (if known) or description of the 
animal(s) involved;
     Condition of the animal(s) (including carcass condition if 
the animal is dead);
     Observed behaviors of the animal(s), if alive;
     If available, photographs or video footage of the 
animal(s); and
     General circumstances under which the animal was 
discovered.
    In the unanticipated event of a ship strike of a marine mammal by 
any vessel involved in the activities covered by the IHA, Mayflower 
must report the incident to the NMFS OPR Permits and Conservation 
Division and the NMFS Northeast Regional Stranding Coordinator as soon 
as feasible. The report must include the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Species identification (if known) or description of the 
animal(s) involved;
     Vessel's speed during and leading up to the incident;
     Vessel's course/heading and what operations were being 
conducted (if applicable);
     Status of all sound sources in use;
     Description of avoidance measures/requirements that were 
in place at the time of the strike and what additional measures were 
taken, if any, to avoid strike;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, visibility) immediately preceding the 
strike;
     Estimated size and length of animal that was struck;
     Description of the behavior of the marine mammal 
immediately preceding and following the strike;
     If available, description of the presence and behavior of 
any other marine mammals immediately preceding the strike;
     Estimated fate of the animal (e.g., dead, injured but 
alive, injured and moving, blood or tissue observed in the water, 
status unknown, disappeared); and
     To the extent practicable, photographs or video footage of 
the animal(s).

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact as an impact resulting from the 
specified activity that cannot be reasonably expected to, and is not 
reasonably likely to, adversely affect the species or stock through 
effects on annual rates of recruitment or survival

[[Page 45594]]

(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. We also 
assess the number, intensity, and context of estimated takes by 
evaluating this information relative to population status. Consistent 
with the 1989 preamble for NMFS's implementing regulations (54 FR 
40338; September 29, 1989), the impacts from other past and ongoing 
anthropogenic activities are incorporated into this analysis via their 
impacts on the environmental baseline (e.g., as reflected in the 
regulatory status of the species, population size and growth rate where 
known, ongoing sources of human-caused mortality, or ambient noise 
levels).
    To avoid repetition, our analysis applies to all the species listed 
in Table 7, given that NMFS expects the anticipated effects of the 
planned survey to be similar in nature. NMFS does not anticipate that 
serious injury or mortality would result from HRG surveys, even in the 
absence of mitigation, and no serious injury or mortality is 
authorized. As discussed in the Potential Effects section of the notice 
of proposed IHA (85 FR 31856; May 27, 2020), non-auditory physical 
effects and vessel strike are not expected to occur. We expect that 
potential takes would be in the form of short-term Level B behavioral 
harassment in the form of temporary avoidance of the area or decreased 
foraging (if such activity were occurring), reactions that are 
considered to be of low severity and with no lasting biological 
consequences (e.g., Southall et al., 2007). As described above, Level A 
harassment is not expected to result given the nature of the 
operations, the anticipated size of the Level A harassment zones, the 
density of marine mammals in the area, and the required shutdown zones.
    Effects on individuals that are taken by Level B harassment, on the 
basis of reports in the literature as well as monitoring from other 
similar activities, will likely be limited to reactions such as 
increased swimming speeds, increased surfacing time, or decreased 
foraging (if such activity were occurring). Most likely, individuals 
will simply move away from the sound source and temporarily avoid the 
area where the survey is occurring. We expect that any avoidance of the 
survey area by marine mammals would be temporary in nature and that any 
marine mammals that avoid the survey area during the survey activities 
would not be permanently displaced. 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.
    Regarding impacts to marine mammal habitat, prey species are 
mobile, and are broadly distributed throughout the Project Area and the 
footprint of the activity is small; 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 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. The HRG survey equipment itself will not 
result in physical habitat disturbance. Avoidance of the area around 
the HRG survey activities by marine mammal prey species is possible. 
However, any avoidance by prey species would be expected to be short 
term and temporary.
    ESA-listed species for which takes are authorized are North 
Atlantic right, fin, sei, and sperm whales, and these effects are 
anticipated to be limited to lower level behavioral effects. The 
planned survey is not anticipated to affect the fitness or reproductive 
success of individual animals. Since impacts to individual survivorship 
and fecundity are unlikely, the planned survey is not expected to 
result in population-level effects for any ESA-listed species or alter 
current population trends of any ESA-listed species.
    The status of the North Atlantic right whale population is of 
heightened concern and, therefore, merits additional analysis. NMFS has 
rigorously assessed potential impacts to right whales from this survey. 
We have established a 500-m shutdown zone for right whales which is 
precautionary considering the Level B harassment isopleth for the 
largest source utilized (i.e. GeoMarine Geo-Source 400 tip sparker) is 
estimated to be 141 m.
    The 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) as well as a migratory BIA for right whales 
(March-April and November-December). 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 
planned survey is sufficiently small, that feeding opportunities for 
these whales would not be reduced appreciably. Any whales temporarily 
displaced from the 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, we do not expect impacts to whales within feeding 
BIAs to effect the fitness of any large whales.
    A migratory BIA for North Atlantic right whales (effective March-
April and November-December) extends from Massachusetts to Florida 
(LaBrecque, et al., 2015). Off the south coast of Massachusetts and 
Rhode Island, this BIA extends from the coast to beyond the shelf 
break. The fact that the spatial acoustic footprint of the planned 
survey is very small relative to the spatial extent of the available 
migratory habitat means that right whale migration is not expected to 
be impacted by the p survey. Required vessel strike avoidance measures 
will also decrease risk of ship strike during migration. NMFS is 
expanding the standard avoidance measures by requiring that all 
vessels, regardless of size, adhere to a 10 knot speed limit in any 
established DMAs. Additionally, limited take by Level B harassment of 
North Atlantic right whales has been authorized as HRG survey 
operations are required to shut down at 500 m to minimize the potential 
for behavioral harassment of this species.
    There are several active unusual mortality events (UMEs) occurring 
in the vicinity of Mayflower's planned surveys. 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

[[Page 45595]]

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. 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 likely 
population abundance is greater than 20,000 whales. Elevated North 
Atlantic right whale mortalities began in June 2017, primarily in 
Canada. Overall, preliminary findings support human interactions, 
specifically vessel strikes or rope entanglements, as the cause of 
death for the majority of the right 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 (345) is well below PBR (2,006) (Hayes et al., 2018). 
For gray seals, the population abundance in the United States is over 
27,000, with an estimated abundance including seals in Canada of 
approximately 505,000, and abundance is likely increasing in the U.S. 
Atlantic Exclusive Economic Zone as well as in Canada (Hayes et al., 
2018).
    Direct physical interactions (ship strikes and entanglements) 
appear to be responsible for many of the UME humpback and right whale 
mortalities recorded. The planned HRG survey will require ship strike 
avoidance measures which would minimize the risk of ship strikes while 
fishing gear and in-water lines will not be employed as part of the 
survey. Furthermore, the planned activities are not expected to promote 
the transmission of infectious disease among marine mammals. The survey 
is not expected to result in the deaths of any marine mammals or 
combine with the effects of the ongoing UMEs to result in any 
additional impacts not analyzed here. Accordingly, Mayflower did not 
request, and NMFS has not authorized, take of marine mammals by serious 
injury, or mortality.
    The required mitigation measures are expected to reduce the number 
and/or severity of takes by giving animals the opportunity to move away 
from the sound source before HRG survey equipment reaches full energy 
and preventing animals from being exposed to sound levels that have the 
potential to cause injury (Level A harassment) and more severe Level B 
harassment during HRG survey activities, even in the biologically 
important areas described above. No Level A harassment is anticipated 
or authorized.
    NMFS expects that takes would be in the form of short-term Level B 
behavioral harassment in the form of brief startling reaction and/or 
temporary vacating of the area, or decreased foraging (if such activity 
were occurring)--reactions that (at the scale and intensity anticipated 
here) are considered to be of low severity and with no lasting 
biological consequences. Since both the source and the marine mammals 
are mobile, only a smaller area would be ensonified by sound levels 
that could result in take for only a short period. Additionally, 
required mitigation measures would reduce exposure to sound that could 
result in more severe behavioral harassment.
    In summary and as described above, the following factors primarily 
support our 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 
authorized;
     No Level A harassment (PTS) is anticipated;
     Any foraging interruptions are expected to be short term 
and unlikely to be cause significantly impacts;
     Impacts on marine mammal habitat and species that serve as 
prey species for marine mammals are expected to be minimal and the 
alternate areas of similar habitat value for marine mammals are readily 
available;
     Take is anticipated to be primarily Level B behavioral 
harassment consisting of brief startling reactions and/or temporary 
avoidance of the Project Area;
     Survey activities would occur in such a comparatively 
small portion of the biologically important area for north Atlantic 
right whale migration, that any avoidance of the Project Area due to 
activities would not affect migration. In addition, mitigation measures 
to shut down at 500 m to minimize potential for Level B behavioral 
harassment would limit both the number and severity of take of the 
species;
     Similarly, due to the relatively small footprint of the 
survey activities in relation to the size of a biologically important 
areas for right, humpback, fin, and sei whales foraging, the survey 
activities would not affect foraging success of this species; and
     Required mitigation measures, including visual monitoring 
and shutdowns, are expected to minimize the intensity of 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 required monitoring and 
mitigation measures, NMFS finds that the total marine mammal take from 
the Mayflower's planned HRG surveys 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. Additionally, other qualitative 
factors may be considered in the analysis, such as the temporal or 
spatial scale of the activities.
    The numbers of marine mammals that we authorize to be taken, for 
all species and stocks, would be considered small relative to the 
relevant stocks or populations (less than one third of the best 
available population abundance for all species and stocks) (see Table 
7). In fact, the total amount of taking authorized for all species is 1 
percent or less for all affected stocks.
    Based on the analysis contained herein of the planned activity 
(including the required mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS finds that small numbers of 
marine mammals will be taken relative to the population size of the 
affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

    There are no relevant subsistence uses of the affected marine 
mammal stocks or species implicated by this action. Therefore, NMFS has 
determined that the total taking of affected species or

[[Page 45596]]

stocks would not have an unmitigable adverse impact on the availability 
of such species or stocks for taking for subsistence purposes.

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 we have not identified any 
extraordinary circumstances that would preclude this categorical 
exclusion. Accordingly, NMFS has determined that the issuance of the 
IHA qualifies to be categorically excluded from further NEPA review.

Endangered Species Act (ESA)

    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 we propose to authorize 
take for endangered or threatened species.
    The NMFS Office of Protected Resources is authorizing the 
incidental take of four species of marine mammals which are listed 
under the ESA: Fin, sei, sperm, and North Atlantic right whales. We 
requested initiation of consultation under section 7 of the ESA with 
NMFS GARFO on May 6, 2020, for the issuance of this IHA. On July 22, 
2020, NMFS GARFO determined our issuance of the IHA to Mayflower was 
not likely to adversely affect the North Atlantic right, fin, sei, and 
sperm whale or the critical habitat of any ESA-listed species or result 
in the take of any marine mammals in violation of the ESA.

Authorization

    NMFS has issued an IHA to Mayflower for the potential harassment of 
small numbers of 14 marine mammal species incidental to the 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, 
provided the previously mentioned mitigation, monitoring and reporting 
requirements are followed.

    Dated: July 23, 2020.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2020-16357 Filed 7-28-20; 8:45 am]
BILLING CODE 3510-22-P