[Federal Register Volume 84, Number 144 (Friday, July 26, 2019)]
[Notices]
[Pages 36054-36082]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-15802]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XG909
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to Site Characterization Surveys of
Lease Areas OCS-A 0486, OCS-A 0487, and OCS-A 0500
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; proposed incidental harassment authorization; request
for comments.
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SUMMARY: NMFS has received an application from Orsted Wind Power LLC
(Orsted) for an Incidental Harassment Authorization (IHA) to take
marine mammals, by harassment, incidental to high-resolution
geophysical (HRG) survey investigations associated with marine site
characterization activities off the coast of Massachusetts and Rhode
Island in the areas of Commercial Lease of Submerged Lands for
Renewable Energy Development on the Outer Continental Shelf (OCS)
currently being leased by the Applicant's affiliates Deepwater Wind New
England, LLC and Bay State Wind LLC, respectively. These are identified
as OCS-A 0486, OCS-A 0487, and OCS-A 0500 (collectively referred to as
the Lease Areas). Orsted is also proposing to conduct marine site
characterization surveys along one or more export cable route corridors
(ECRs) originating from the Lease Areas and landing along the shoreline
at locations from New York to Massachusetts, between Raritan Bay (part
of the New York Bight) to Falmouth, Massachusetts (see Figure 1).
Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting
comments on its proposal to issue an IHA to Orsted to incidentally
take, by Level B harassment only, small numbers of marine mammals
during the specified activities. NMFS will consider public comments
prior to making any final decision on the issuance of the requested
MMPA authorizations and agency responses will be summarized in the
final notice of our decision.
DATES: Comments and information must be received no later than August
26, 2019.
ADDRESSES: Comments should be addressed to Jolie Harrison, Chief,
Permits and Conservation Division, Office of Protected Resources,
National
[[Page 36055]]
Marine Fisheries Service. Physical comments should be sent to 1315
East-West Highway, Silver Spring, MD 20910 and electronic comments
should be sent to [email protected].
Instructions: NMFS is not responsible for comments sent by any
other method, to any other address or individual, or received after the
end of the comment period. Comments received electronically, including
all attachments, must not exceed a 25-megabyte file size. Attachments
to electronic comments will be accepted in Microsoft Word or Excel or
Adobe PDF file formats only. All comments received are a part of the
public record and will generally be posted online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-other-energy-activities-renewable without change.
All personal identifying information (e.g., name, address) voluntarily
submitted by the commenter may be publicly accessible. Do not submit
confidential business information or otherwise sensitive or protected
information.
FOR FURTHER INFORMATION CONTACT: Rob Pauline, Office of Protected
Resources, NMFS, (301) 427-8401. Electronic copies of the application
and supporting documents, as well as a list of the references cited in
this document, may be obtained online at: https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act. In case of problems accessing these
documents, please call the contact listed above.
SUPPLEMENTARY INFORMATION:
Background
The MMPA prohibits the ``take'' of marine mammals, with certain
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to
allow, upon request, the incidental, but not intentional, taking of
small numbers of marine mammals by U.S. citizens who engage in a
specified activity (other than commercial fishing) within a specified
geographical region if certain findings are made and either regulations
are issued or, if the taking is limited to harassment, a notice of a
proposed incidental take authorization may be provided to the public
for review.
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other ``means of effecting the least practicable adverse
impact'' on the affected species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of such 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 such takings are set forth.
National Environmental Policy Act (NEPA)
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.
Accordingly, NMFS is preparing an Environmental Assessment (EA) to
consider the environmental impacts associated with the issuance of the
proposed IHA. NMFS' [EIS or EA] [was or will be] made available at
https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.
We will review all comments submitted in response to this notice
prior to concluding our NEPA process or making a final decision on the
IHA request.
Summary of Request
On March 8, 2019, NMFS received an application from Orsted for the
taking of marine mammals incidental to HRG and geotechnical survey
investigations in the OCS-A 0486, OCS-A 0487, and OCS-A 0500 Lease
Areas, designated and offered by the Bureau of Ocean Energy Management
(BOEM) as well as along one or more ECRs between the southern portions
of the Lease Areas and shoreline locations from New York to
Massachusetts, to support the development of an offshore wind project.
Orsted's request is for take, by Level B harassment, of small numbers
of 15 species or stocks of marine mammals. The application was
considered adequate and complete on May 23, 2019. Neither Orsted nor
NMFS expects serious injury or mortality to result from this activity
and, therefore, an IHA is appropriate.
NMFS previously issued two IHAs to both Bay State Wind (81 FR
56589, August 22, 2016; 83 FR 36539, July 30, 2018) and Deepwater Wind
(82 FR 32230, July 13, 2017; 83 FR 28808, June 21, 2018) for similar
activities. Orsted has complied with all the requirements (e.g.,
mitigation, monitoring, and reporting) of the issued IHAs.
Description of the Specified Activity
Overview
Orsted proposes to conduct HRG surveys in the Lease Area and ECRs
to support the characterization of the existing seabed and subsurface
geological conditions. This information is necessary to support the
final siting, design, and installation of offshore project facilities,
turbines and subsea cables within the project area as well as to
collect the data necessary to support the review requirements
associated with Section 106 of the National Historic Preservation Act
of 1966, as amended. Underwater sound resulting from Orsted's proposed
site characterization surveys has the potential to result in incidental
take of marine mammals. This take of marine mammals is anticipated to
be in the form of harassment and no serious injury or mortality is
anticipated, nor is any authorized in this IHA.
Dates and Duration
HRG surveys are anticipated to commence in August, 2019. Orsted is
proposing to conduct continuous HRG survey operations 24-hours per day
(Lease Area and ECR Corridors) using multiple vessels. Based on the
planned 24-hour operations, the survey activities for all survey
segments would require 666 vessel days total if one vessel were
surveying the entire survey line continuously. However, an estimated 5
vessels may be used simultaneously with a maximum of no more than 9
vessels. Therefore, all of the survey will be completed within one
year. See Table 1 for the estimated number of vessel days for each
survey segment. This is considered the total number of vessel days
required, regardless of the number of vessels used. While actual survey
duration would shorten given the use of multiple vessels, total vessel
days provides an equivalent estimate of exposure for a given area. The
estimated durations to complete survey activities do not include
weather downtime. Surveys are anticipated to commence upon issuance of
the requested IHA, if appropriate.
[[Page 36056]]
Table 1--Summary of Proposed HRG Survey Segments
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Total duration
Survey segment Total line km (vessel
per day days) *
------------------------------------------------------------------------
Lease Area OCS-A 0486................... 70 79
Lease Area OCS-A 0487................... .............. 140
Lease Area OCS-A 0500................... .............. 94
ECR Corridor(s)......................... .............. 353
-------------------------------
Total............................... .............. 666
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* Estimate is based on total time for one (1) vessel to complete survey
activities.
Specified Geographic Region
Orsted's survey activities will occur in the Lease Areas designated
and offered by BOEM, located approximately 14 miles (mi) south of
Martha's Vineyard, Massachusetts at its closest point, as well as
within potential export cable route corridors off the coast of New
York, Connecticut, Rhode Island, and Massachusetts shown in Figure 1.
Water depth in these areas for the majority of the survey area is 1-55
m. However south of Long Island in the area we are surveying for cable
routes, the maximum depth reaches 77 m in some locations. Also there is
a very small area in the area north of the eastern end of Long Island
that reaches a depth of 123 m.
BILLING CODE 3510-22-P
[GRAPHIC] [TIFF OMITTED] TN26JY19.000
[[Page 36057]]
BILLING CODE 3510-22-C
Detailed Description of Specified Activities
Marine site characterization surveys will include the following HRG
survey activities:
Depth sounding (multibeam depth sounder) to determine
water depths and general bottom topography (currently estimated to
range from approximately 3 to 180 feet (ft), 1 to 55 m, in depth below
mean lower low water);
Magnetic intensity measurements for detecting local
variations in regional magnetic field from geological strata and
potential ferrous objects on and below the seabed;
Seafloor imaging (sidescan sonar survey) for seabed
sediment classification purposes, to identify natural and man-made
acoustic targets resting on the bottom as well as any anomalous
features;
Sub-bottom profiler to map the near surface stratigraphy;
and
Ultra High Resolution Seismic (UHRS) equipment to map
deeper subsurface stratigraphy as needed.
Table 2 identifies the representative survey equipment that is
being considered in support of the HRG survey activities. The make and
model of the HRG equipment will vary depending on availability. The
primary operating frequency is oftentimes defined by the HRG equipment
manufacturer or HRG contractor. The pulse duration provided represents
best engineering estimates of the RMS90 values based on
anticipated operator and sound source verification (SSV) reports of
similar equipment (see Appendix E in Application). Orsted SSV reports
also provide relevant information on anticipated settings. For most HRG
sources, the midrange frequency is typically deemed appropriate for
hydroacoustic assessment purposes. The SSV reports have also reasonably
assumed that the HRG equipment were being operated at configurations
deemed appropriate for the Survey Area. None of the proposed HRG survey
activities will result in the disturbance of bottom habitat in the
Survey Area.
Table 2--Summary of Proposed HRG Survey Data Acquisition Equipment
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Range of Representative Primary
Representative HRG survey operating Baseline source RMS90 pulse Pulse operating
equipment frequencies level \a\ duration repetition frequency
(kHz) (millisec) rate (Hz) (kHz)
----------------------------------------------------------------------------------------------------------------
USBL & Global Acoustic Positioning System (GAPS) Transceiver
----------------------------------------------------------------------------------------------------------------
Sonardyne Ranger 2 19-34........... 200 dBRMS...... 300 1 26
transponder \b\.
Sonardyne Ranger 2 USBL HPT 5/ 19 to 34........ 200 dBRMS...... 300 1 26
7000 transceiver \b\.
Sonardyne Ranger 2 USBL HPT 19 to 34........ 194 dBRMS...... 300 3 26.5
3000 transceiver \b\.
Sonardyne Scout Pro 35 to 50........ 188 dBRMS...... 300 1 42.5
transponder \b\.
Easytrak Nexus 2 USBL 18 to 32........ 192 dBRMS...... 300 1 26
transceiver \b\.
IxSea GAPS transponder \b\... 20 to 32........ 188 dBRMS...... 20 10 26
Kongsberg HiPAP 501/502 USBL 21 to 31........ 190 dBRMS...... 300 1 26
transceiver \b\.
Edgetech BATS II transponder 17 to30......... 204 dBRMS...... 300 3 23.5
\b\.
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Shallow Sub-Bottom Profiler (Chirp)
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Edgetech 3200 \c\............ 2 to 16......... 212 dBRMS...... 150 5 9
EdgeTech 216 \b\............. 2 to 16......... 174 dBRMS...... 22 2 6
EdgeTech 424 \b\............. 4 to 24......... 176 dBRMS...... 3.4 2 12
EdgeTech 512 \b\............. 0.5 to 12....... 177 dBRMS...... 2.2 2 3
Teledyne Benthos Chirp III-- 2 to 7.......... 197 dBRMS...... 5 to 60 4 3.5
TTV 170 \b\.
GeoPulse 5430 A Sub-bottom 1.5 to 18....... 214 dBRMS...... 25 10 4.5
Profiler \b\ \e\.
PanGeo LF Chirp \b\.......... 2 to 6.5........ 195 dBRMS...... 481.5 0.06 3
PanGeo HF Chirp \b\.......... 4.5 to 12.5..... 190 dBRMS...... 481.5 0.06 5
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Parametric Sub-Bottom Profiler
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Innomar SES-2000 Medium 100 85 to 115....... 247 dBRMS...... 0.07 to 2 40 85
\c\.
Innomar SES-2000 Standard & 85 to 115....... 236 dBRMS...... 0.07 to 2 60 85
Plus \b\.
Innomar SES-2000 Medium 70 60 to 80........ 241 dBRMS...... 0.1 to 2.5 40 70
\b\.
Innomar SES-2000 Quattro \b\. 85 to 115....... 245 dBRMS...... 0.07 to 1 60 85
PanGeo 2i Parametric \b\..... 90-115.......... 239 dBRMS...... 0.33 40 102
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Medium Penetration Sub-Bottom Profiler (Sparker)
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GeoMarine Geo-Source 400tip 0.2 to 5........ 212 dBPeak; 201 55 2 2
\d\. dBRMS.
GeoMarine Geo-Source 600tip 0.2 to 5........ 214 dBPeak; 205 55 2 2
\d\. dBRMS.
GeoMarine Geo-Source 800tip 0.2 to 5........ 215 dBPeak; 206 55 2 2
\d\. dBRMS.
Applied Acoustics Dura-Spark 0.3 to 1.2...... 225 dBPeak; 214 55 0.4 1
400 System \d\. dBRMS.
GeoResources Sparker 800 0.05 to 5....... 215 dBPeak; 206 55 2.5 1.9
System \d\. dBRMS.
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[[Page 36058]]
Medium Penetration Sub-Bottom Profiler (Boomer)
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Applied Acoustics S-Boom 0.250 to 8...... 228 dBPeak;.... 0.6 3 0.6
1000J b. 208 dBRMS......
Applied Acoustics S-Boom 700J 0.1 to 5........ 211 dBPeak;.... 5 3 0.6
\b\. 205 dBRMS......
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Notes:
\a\ Baseline source levels were derived from manufacturer-reported source levels (SL) when available either in
the manufacturer specification sheet or from the SSV report. When manufacturer specifications were unavailable
or unclear, Crocker and Fratantonio (2016) SLs were utilized as the baseline:
\b\ source level obtained from manufacturer specifications;
\c\ source level obtained from SSV-reported manufacturer SL;
\d\ source level obtained from Crocker and Fratantonio (2016);
\e\ unclear from manufacturer specifications and SSV whether SL is reported in peak or rms; however, based on
SLpk source level reported in SSV, assumption is SLrms is reported in specifications.
The transmit frequencies of sidescan and multibeam sonars for the 2019 marine site characterization surveys
operate outside of marine mammal functional hearing frequency range.
The deployment of HRG survey equipment, including the use of
intermittent, impulsive sound-producing equipment operating below 200
kilohertz (kHz), has the potential to cause acoustic harassment to
marine mammals. Based on the frequency ranges of the equipment to be
used in support of the HRG survey activities (Table 2) and the hearing
ranges of the marine mammals that have the potential to occur in the
Survey Area during survey activities (Table 3), the noise produced by
the ultrashort baseline (USBL) and global acoustic positioning system
(GAPS) transceiver systems; sub-bottom profilers (parametric and
chirp); sparkers; and boomers fall within the established marine mammal
hearing ranges and have the potential to result in harassment of marine
mammals. All HRG equipment proposed for use is shown in Table 2.
Assuming a maximum survey track line to fully cover the Survey
Area, the survey activities will be supported by vessels sufficient in
size to accomplish the survey goals in specific survey areas and
capable of maintaining both the required course and a survey speed to
cover approximately 70.0 kilometers (km) per day at a speed of 4 knots
(7.4 km per hour) while acquiring survey lines. While survey tracks
could shorten, the maximum survey track scenario has been selected to
provide operational flexibility and to cover the possibility of
multiple landfall locations and associated cable routes. Survey
segments represent a maximum extent, and distances may vary depending
on contractor used.
Orsted has proposed to reduce the total duration of survey
activities and minimize cost by conducting continuous HRG survey
operations 24-hours per day for all survey segments. Total survey
effort has been conservatively estimated to require up to a full year
to provide survey flexibility on specific locations and vessel numbers
to be utilized (likely between 5-9), which will be determined at the
time of contractor selection.
Orsted also proposes to complete the proposed survey quickly and
efficiently by using multiple vessels of varying size depending on
survey segment location. To reduce the total survey duration,
simultaneous survey activities will occur across multiple vessels in
respective survey segments, where appropriate. Additionally, Orsted may
elect to use an autonomous surface vehicle (ASV) to support survey
operations. Use of an ASV in combination with a mother vessel allows
the project team to double the survey daily production. The ASV will
capture data in water depths shallower than 26 ft (8 m), increasing the
shallow end reach of the larger vessel. The ASV can be used for
nearshore operations and shallow work (20 ft (6 m) and less) in a
``manned'' configuration. The ASV and mother vessel will acquire survey
data in tandem and the ASV will be kept within sight of the mother
vessel at all times. The ASV will operate autonomously along a parallel
track to, and slightly ahead of, the mother vessel at a distance set to
prevent crossed signaling of survey equipment (within 2,625 ft (800 m))
During data acquisition surveyors have full control of the data being
acquired and have the ability to make changes to settings such as
power, gain, range scale etc. in real time.
Proposed mitigation, monitoring, and reporting measures are
described in detail later in this document (please see ``Proposed
Mitigation'' and ``Proposed Monitoring and Reporting'').
Description of Marine Mammals in the Area of the Specified Activity
Sections 3 and 4 of the application summarize available information
regarding status and trends, distribution and habitat preferences, and
behavior and life history, of the potentially affected species.
Additional information regarding population trends and threats may be
found in NMFS' Stock Assessment Reports (SAR; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species
(e.g., physical and behavioral descriptions) may be found on NMFS'
website (https://www.fisheries.noaa.gov/find-species).
We expect that the species listed in Table 3 will potentially occur
in the project area and will potentially be taken as a result of the
proposed project. Table 3 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 (2018). 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' SARs). While no mortality is anticipated or authorized here, PBR
is included here as a gross indicator of the status of the species and
other threats.
Marine mammal abundance estimates presented in this document
represent
[[Page 36059]]
the total number of individuals that make up a given stock or the total
number estimated within a particular study or survey area. NMFS' stock
abundance estimates for most species represent the total estimate of
individuals within the geographic area, if known, that comprise that
stock. For some species, this geographic area may extend beyond U.S.
waters. All managed stocks in this region are assessed in NMFS' U.S.
Atlantic Ocean SARs (e.g., Hayes et al., 2018). All values presented in
Table 3 are the most recent available at the time of publication and
are available in the 2017 SARs (Hayes et al., 2018) and draft 2018 SARs
(available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/draft-marine-mammal-stock-assessment-reports).
Table 3--Marine Mammal Known to Occur in Survey Area Waters
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ESA/MMPA status; Stock abundance (CV,
Common name Scientific name Stock strategic (Y/N) Nmin, most recent PBR Annual M/
\1\ abundance survey) \2\ SI \3\
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Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
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Family Balaenidae:
North Atlantic Right whale..... Eubalaena glacialis... Western North Atlantic E/D; Y 451 (0; 445; 2017)... 0.9 5.56
(WNA).
Family Balaenopteridae (rorquals):
Humpback whale................. Megaptera novaeangliae Gulf of Maine......... -/-; N 896 (0; 896; 2012)... 14.6 9.7
Fin whale...................... Balaenoptera physalus. WNA................... E/D; Y 1,618 (0.33; 1,234; 2.5 2.5
2011).
Sei whale...................... Balaenoptera borealis. Nova Scotia........... E/D; Y 357 (0.52; 236)...... 0.5 0.8
Minke whale.................... Balaenoptera Canadian East Coast... -/-; N 2,591 (0.81; 1,425).. 14 7.7
acutorostrata.
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Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
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Family Physeteridae:
Sperm whale.................... Physeter macrocephalus E; Y.................. 2,288 North Atlantic....... 3.6 0.8
(0.28;
1,815)
Family Delphinidae:
Long-finned pilot whale........ Globicephala melas.... WNA................... -/-; Y 5,636 (0.63; 3,464).. 35 38
Bottlenose dolphin................. Tursiops spp.......... WNA Offshore.......... -/-; N 77,532 (0.40; 56053; 561 39.4
2016).
Short beaked common dolphin........ Delphinus delphis..... WNA................... -/-; N 70,184 (0.28; 55,690; 557 406
2011).
Atlantic white-sided dolphin....... Lagenorhynchus acutus. WNA................... -/-; N 48,819 (0.61; 30,403; 304 30
2011).
Atlantic spotted dolphin........... Stenella frontalis.... WNA................... -/-: N 44,715 (0.43; 31,610; 316 0
2013).
Risso's dolphin.................... Grampus griseus....... WNA................... -/-; N 18,250 (0.5; 12,619; 126 49.7
2011).
Family Phocoenidae (porpoises):
Harbor porpoise................ Phocoena phocoena..... Gulf of Maine/Bay of -/-; N 79,833 (0.32; 61,415; 706 256
Fundy. 2011).
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Order Carnivora--Superfamily Pinnipedia
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Phocidae (earless seals):
Gray seal.......................... Halichoerus grypus.... -; N.................. 27,131 W. North Atlantic.... 1,389 5,688
(0.19;
23,158)
Harbor seal........................ Phoca vitulina........ -; N.................. 75,834 W. North Atlantic.... 345 333
(0.15;
66,884)
--------------------------------------------------------------------------------------------------------------------------------------------------------
\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\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range.
[[Page 36060]]
As described below, 15 species (with 15 managed stocks) temporally
and spatially co-occur with the activity to the degree that take is
reasonably likely to occur, and we have proposed authorizing it.
The following subsections provide additional information on the
biology, habitat use, abundance, distribution, and the existing threats
to the non-ESA-listed and ESA-listed marine mammals that are both
common in the waters of the outer continental shelf (OCS) of Southern
New England and have the likelihood of occurring, at least seasonally,
in the Survey Area. These species include the North Atlantic right,
humpback, fin, sei, minke, sperm, and long finned pilot whale,
bottlenose, short-beaked common, Atlantic white-sided, Atlantic
spotted, and Risso's dolphins, harbor porpoise, and gray and harbor
seals (BOEM 2014). Although the potential for interactions with long-
finned pilot whales and Atlantic spotted and Risso's dolphins is
minimal, small numbers of these species may transit the Survey Area and
are included in this analysis.
Cetaceans
North Atlantic Right Whale
The North Atlantic right whale ranges from the calving grounds in
the southeastern United States to feeding grounds in New England waters
and into Canadian waters (Waring et al., 2017). Right whales have been
observed in or near southern New England during all four seasons;
however, they are most common in the spring when they are migrating
north and in the fall during their southbound migration (Kenney and
Vigness-Raposa 2009). Surveys have demonstrated the existence of seven
areas where North Atlantic right whales congregate seasonally,
including north and east of the proposed survey area in Georges Bank,
off Cape Cod, and in Massachusetts Bay (Waring et al., 2017). In
addition modest late winter use of a region south of Martha's Vineyard
and Nantucket Islands was recently described (Stone et al. 2017). A
large increase in aerial surveys of the Gulf of St. Lawrence documented
at least 36 and 117 unique individuals using the region, respectively,
during the summers of 2015 and 2017 (NMFS unpublished data). In the
late fall months (e.g. October), right whales are generally thought to
depart from the feeding grounds in the North Atlantic and move south to
their calving grounds off Florida. However, recent research indicates
our understanding of their movement patterns remains incomplete (Davis
et al. 2017). A review of passive acoustic monitoring data from 2004 to
2014 throughout the western North Atlantic Ocean demonstrated nearly
continuous year-round right whale presence across their entire habitat
range, including in locations previously thought of as migratory
corridors, suggesting that not all of the population undergoes a
consistent annual migration (Davis et al. 2017). The number of North
Atlantic right whale vocalizations detected in the proposed survey area
were relatively constant throughout the year, with the exception of
August through October when detected vocalizations showed an apparent
decline (Davis et al. 2017). North Atlantic right whales are expected
to be present in the proposed survey area during the proposed survey,
especially during the summer months, with numbers possibly lower in the
fall. The proposed survey area is part of a migratory Biologically
Important Area (BIA) for North Atlantic right whales; this important
migratory area is comprised of the waters of the continental shelf
offshore the East Coast of the United States and extends from Florida
through Massachusetts. A map showing designated BIAs is available at:
https://cetsound.noaa.gov/biologically-important-area-map.
NMFS' regulations at 50 CFR part 224.105 designated nearshore
waters of the Mid-Atlantic Bight as Mid-Atlantic U.S. Seasonal
Management Areas (SMA) for right whales in 2008. SMAs were developed to
reduce the threat of collisions between ships and right whales around
their migratory route and calving grounds. A portion of one SMA,
overlaps spatially with a section of the proposed survey area. The SMA
is active from November 1 through April 30 of each year.
The western North Atlantic population demonstrated overall growth
of 2.8 percent per year between 1990 to 2010, despite a decline in
1993, and no growth between 1997 and 2000 (Pace et al. 2017). However,
since 2010 the population has been in decline, with a 99.99 percent
probability of a decline of just under 1 percent per year (Pace et al.
2017). Between 1990 and 2015, calving rates varied substantially, with
low calving rates coinciding with all three periods of decline or no
growth (Pace et al. 2017). In 2018, no new North Atlantic right whale
calves were documented in their calving grounds; this represented the
first time since annual NOAA aerial surveys began in 1989 that no new
right whale calves were observed. However, in 2019 at least seven right
whale calves have been identified (Savio 2019). Data indicates that the
number of adult females fell from 200 in 2010 to 186 in 2015 while
males fell from 283 to 272 in the same time frame (Pace et al., 2017).
In addition, elevated North Atlantic right whale mortalities have
occurred since June 7, 2017. A total of 26 confirmed dead stranded
whales (18 in Canada; 8 in the United States), have been documented to
date. This event has been declared an Unusual Mortality Event (UME),
with human interactions (i.e., fishery-related entanglements and vessel
strikes) identified as the most likely cause. More information is
available online at: https://www.fisheries.noaa.gov/national/marine-life-distress/2017-2018-north-atlantic-right-whale-unusual-mortality-event.
Humpback Whale
Humpback whales are found worldwide in all oceans. Humpback whales
were listed as endangered under the Endangered Species Conservation Act
(ESCA) in June 1970. In 1973, the ESA replaced the ESCA, and humpbacks
continued to be listed as endangered. NMFS recently evaluated the
status of the species, and on September 8, 2016, NMFS divided the
species into 14 distinct population segments (DPS), removed the current
species-level listing, and in its place listed four DPSs as endangered
and one DPS as threatened (81 FR 62259; September 8, 2016). The
remaining nine DPSs were not listed. The West Indies DPS, which is not
listed under the ESA, is the only DPS of humpback whale that is
expected to occur in the survey area. The best estimate of population
abundance for the West Indies DPS is 12,312 individuals, as described
in the NMFS Status Review of the Humpback Whale under the Endangered
Species Act (Bettridge et al., 2015).
In New England waters, feeding is the principal activity of
humpback whales, and their distribution in this region has been largely
correlated to abundance of prey species, although behavior and
bathymetry are factors influencing foraging strategy (Payne et al.
1986, 1990). Humpback whales are frequently piscivorous when in New
England waters, feeding on herring (Clupea harengus), sand lance
(Ammodytes spp.), and other small fishes, as well as euphausiids in the
northern Gulf of Maine (Paquet et al. 1997). During winter, the
majority of humpback whales from North Atlantic feeding areas
(including the Gulf of Maine) mate and calve in the West Indies, where
spatial and genetic mixing among feeding groups occurs, though
significant numbers of animals are found in mid- and high-latitude
regions
[[Page 36061]]
at this time and some individuals have been sighted repeatedly within
the same winter season, indicating that not all humpback whales migrate
south every winter (Waring et al., 2017). Other sightings of note
include 46 sightings of humpbacks in the New York- New Jersey Harbor
Estuary documented between 2011 and 2016 (Brown et al. 2017). Multiple
humpbacks were observed feeding off Long Island during July of 2016
(https://www.greateratlantic.fisheries.noaa.gov/mediacenter/2016/july/26_humpback_whales_visit_new_york.html, accessed 31 December, 2018) and
there were sightings during November-December 2016 near New York City
(https://www.greateratlantic.fisheries.noaa.gov/mediacenter/2016/december/09_humans_and_humpbacks_of_new_york_2.html, accessed 31
December 2018).
Since January 2016, elevated humpback whale mortalities have
occurred along the Atlantic coast from Maine through Florida. The event
has been declared a UME. Partial or full necropsy examinations have
been conducted on approximately half of the 93 known cases. A portion
of the whales have shown evidence of pre-mortem vessel strike; however,
this finding is not consistent across all of the whales examined so
more research is needed. NOAA is consulting with researchers that are
conducting studies on the humpback whale populations, and these efforts
may provide information on changes in whale distribution and habitat
use that could provide additional insight into how these vessel
interactions occurred. More detailed information is available at:
https://www.fisheries.noaa.gov/national/marine-life-distress/2016-2018-humpback-whale-unusual-mortality-event-along-atlantic-coast#causes-of-the-humpback-whale-ume (accessed June 3, 2019). Three previous UMEs
involving humpback whales have occurred since 2000, in 2003, 2005, and
2006.
Fin Whale
Fin whales are common in waters of the U. S. Atlantic Exclusive
Economic Zone (EEZ), principally from Cape Hatteras northward (Waring
et al., 2017). Fin whales are present north of 35-degree latitude in
every season and are broadly distributed throughout the western North
Atlantic for most of the year, though densities vary seasonally (Waring
et al., 2017). The main threats to fin whales are fishery interactions
and vessel collisions (Waring et al., 2017). New England waters
represent a major feeding ground for fin whales. The proposed survey
area would overlap spatially and temporally with a feeding BIA for fin
whales. The important fin whale feeding area occurs from March through
October and stretches from an area south of Montauk Point to south of
Martha's Vineyard.
Sei Whale
The Nova Scotia stock of sei whales can be found in deeper waters
of the continental shelf edge waters of the northeastern United States
and northeastward to south of Newfoundland. NOAA Fisheries considers
sei whales occurring from the U.S. East Coast to Cape Breton, Nova
Scotia, and east to 42[deg] W as the Nova Scotia stock of sei whales
(Waring et al. 2016; Hayes et al. 2018). In the Northwest Atlantic, it
is speculated that the whales migrate from south of Cape Cod along the
eastern Canadian coast in June and July, and return on a southward
migration again in September and October (Waring et al. 2014; 2017).
Spring is the period of greatest abundance in U.S. waters, with
sightings concentrated along the eastern margin of Georges Bank and
into the Northeast Channel area, and along the southwestern edge of
Georges Bank in the area of Hydrographer Canyon (Waring et al., 2015).
Minke Whale
Minke whales can be found in temperate, tropical, and high-latitude
waters. The Canadian East Coast stock can be found in the area from the
western half of the Davis Strait (45[deg] W) to the Gulf of Mexico
(Waring et al., 2017). This species generally occupies waters less than
100 m deep on the continental shelf. There appears to be a strong
seasonal component to minke whale distribution in which spring to fall
are times of relatively widespread and common occurrence, and when the
whales are most abundant in New England waters, while during winter the
species appears to be largely absent (Waring et al., 2017).
Since 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. Partial or full
necropsy examinations have been conducted on more than 60 percent of
the 59 known cases. Preliminary findings in several of the whales have
shown evidence of human interactions or infectious disease. These
findings are not consistent across all of the whales examined, so more
research is needed. As part of the UME investigation process, NOAA is
assembling an independent team of scientists to coordinate with the
Working Group on Marine Mammal Unusual Mortality Events to review the
data collected, sample stranded whales, and determine the next steps
for the investigation. More information is available at:
www.fisheries.noaa.gov/national/marine-life-distress/2017-2018-minke-whale-unusual-mortality-event-along-atlantic-coast (accessed June 3,
2019).
Sperm Whale
The distribution of the sperm whale in the U.S. EEZ occurs on the
continental shelf edge, over the continental slope, and into mid-ocean
regions (Waring et al. 2014). The basic social unit of the sperm whale
appears to be the mixed school of adult females plus their calves and
some juveniles of both sexes, normally numbering 20-40 animals in all.
Sperm whales are somewhat migratory; however, their migrations are not
as specific as seen in most of the baleen whale species. In the North
Atlantic, there appears to be a general shift northward during the
summer, but there is no clear migration in some temperate areas (Rice
1989). In summer, the distribution of sperm whales includes the area
east and north of Georges Bank and into the Northeast Channel region,
as well as the continental shelf (inshore of the 100-m isobath) south
of New England. In the fall, sperm whale occurrence south of New
England on the continental shelf is at its highest level, and there
remains a continental shelf edge occurrence in the mid-Atlantic bight.
In winter, sperm whales are concentrated east and northeast of Cape
Hatteras. Their distribution is typically associated with waters over
the continental shelf break and the continental slope and into deeper
waters (Whitehead et al. 1991). Sperm whale concentrations near drop-
offs and areas with strong currents and steep topography are correlated
with high productivity. These whales occur almost exclusively found at
the shelf break, regardless of season.
Long-Finned Pilot Whale
Long-finned pilot whales are found from North Carolina and north to
Iceland, Greenland and the Barents Sea (Waring et al., 2016). They are
generally found along the edge of the continental shelf (a depth of 330
to 3,300 feet (100 to 1,000 meters)), choosing areas of high relief or
submerged banks in cold or temperate shoreline waters. In the western
North Atlantic, long-finned pilot whales are pelagic, occurring in
especially high densities in winter and spring over the continental
slope, then moving inshore and onto the shelf in summer and autumn
following squid
[[Page 36062]]
and mackerel populations (Reeves et al. 2002). They frequently travel
into the central and northern Georges Bank, Great South Channel, and
Gulf of Maine areas during the late spring and remain through early
fall (May and October) (Payne and Heinemann 1993).
Atlantic White-Sided Dolphin
White-sided dolphins are found in temperate and sub-polar waters of
the North Atlantic, primarily in continental shelf waters to the 100-m
depth contour from central West Greenland to North Carolina (Waring et
al., 2017). The Gulf of Maine stock is most common in continental shelf
waters from Hudson Canyon to Georges Bank, and in the Gulf of Maine and
lower Bay of Fundy. Sighting data indicate seasonal shifts in
distribution (Northridge et al., 1997). During January to May, low
numbers of white-sided dolphins are found from Georges Bank to Jeffreys
Ledge (off New Hampshire), with even lower numbers south of Georges
Bank, as documented by a few strandings collected on beaches of
Virginia to South Carolina. From June through September, large numbers
of white-sided dolphins are found from Georges Bank to the lower Bay of
Fundy. From October to December, white-sided dolphins occur at
intermediate densities from southern Georges Bank to southern Gulf of
Maine (Payne and Heinemann 1990). Sightings south of Georges Bank,
particularly around Hudson Canyon, occur year round but at low
densities.
Atlantic Spotted Dolphin
Atlantic spotted dolphins are found in tropical and warm temperate
waters ranging from southern New England, south to Gulf of Mexico and
the Caribbean to Venezuela (Waring et al., 2014). This stock regularly
occurs in continental shelf waters south of Cape Hatteras and in
continental shelf edge and continental slope waters north of this
region (Waring et al., 2014). There are two forms of this species, with
the larger ecotype inhabiting the continental shelf and is usually
found inside or near the 200 m isobaths (Waring et al., 2014). The
smaller ecotype has less spots and occurs in the Atlantic Ocean, but is
not known to occur in the Gulf of Mexico. Atlantic spotted dolphins are
not listed under the ESA and the stock is not considered depleted or
strategic under the MMPA.
Common Dolphin
The short-beaked common dolphin is found world-wide in temperate to
subtropical seas. In the North Atlantic, short-beaked common dolphins
are commonly found over the continental shelf between the 100-m and
2,000-m isobaths and over prominent underwater topography and east to
the mid-Atlantic Ridge (Waring et al., 2016). This species is found
between Cape Hatteras and Georges Bank from mid-January to May,
although they migrate onto the northeast edge of Georges Bank in the
fall where large aggregations occur (Kenney and Vigness-Raposa 2009),
where large aggregations occur on Georges Bank in fall (Waring et al.
2007). Only the western North Atlantic stock may be present in the
Survey Area.
Bottlenose Dolphin
There are two distinct bottlenose dolphin ecotypes in the western
North Atlantic: The coastal and offshore forms (Waring et al., 2015).
The migratory coastal morphotype resides in waters typically less than
65.6 ft (20 m) deep, along the inner continental shelf (within 7.5 km
(4.6 miles) of shore), around islands, and is continuously distributed
south of Long Island, New York into the Gulf of Mexico. This migratory
coastal population is subdivided into 7 stocks based largely upon
spatial distribution (Waring et al. 2015). Of these 7 coastal stocks,
the Western North Atlantic migratory coastal stock is common in the
coastal continental shelf waters off the coast of New Jersey (Waring et
al. 2017). Generally, the offshore migratory morphotype is found
exclusively seaward of 34 km (21 miles) and in waters deeper than 34 m
(111.5 feet). This morphotype is most expected in waters north of Long
Island, New York (Waring et al. 2017; Hayes et al. 2017; 2018). The
offshore form is distributed primarily along the outer continental
shelf and continental slope in the Northwest Atlantic Ocean from
Georges Bank to the Florida Keys and is the only type that may be
present in the survey area as the survey area is north of the northern
extent of the range of the Western North Atlantic Northern Migratory
Coastal Stock.
Risso's Dolphins
Risso's dolphins are distributed worldwide in tropical and
temperate seas (Jefferson et al. 2008, 2014), and in the Northwest
Atlantic occur from Florida to eastern Newfoundland (Leatherwood et al.
1976; Baird and Stacey 1991). Off the northeastern U.S. coast, Risso's
dolphins are distributed along the continental shelf edge from Cape
Hatteras northward to Georges Bank during spring, summer, and autumn
(CETAP 1982; Payne et al. 1984) (Figure 1). In winter, the range is in
the mid-Atlantic Bight and extends outward into oceanic waters (Payne
et al. 1984).
Harbor Porpoise
In the Survey Area, only the Gulf of Maine/Bay of Fundy stock may
be present. This stock is found in U.S. and Canadian Atlantic waters
and is concentrated in the northern Gulf of Maine and southern Bay of
Fundy region, generally in waters less than 150 m deep (Waring et al.,
2017). During fall (October-December) and spring (April-June) harbor
porpoises are widely dispersed from New Jersey to Maine. During winter
(January to March), intermediate densities of harbor porpoises can be
found in waters off New Jersey to North Carolina, and lower densities
are found in waters off New York to New Brunswick, Canada They are seen
from the coastline to deep waters (>1800 m; Westgate et al. 1998),
although the majority of the population is found over the continental
shelf (Waring et al., 2017).
Harbor Seal
Harbor seals are year-round inhabitants of the coastal waters of
eastern Canada and Maine (Katona et al. 1993), and occur seasonally
along the coasts from southern New England to New Jersey from September
through late May. While harbor seals occur year-round north of Cape
Cod, they only occur during winter migration, typically September
through May, south of Cape Cod (Southern New England to New Jersey)
(Waring et al. 2015; Kenney and Vigness-Raposa 2009).
Gray Seal
There are three major populations of gray seals found in the world;
eastern Canada (western North Atlantic stock), northwestern Europe and
the Baltic Sea. Gray seals in the survey area belong to the western
North Atlantic stock. The range for this stock is thought to be from
New Jersey to Labrador. Current population trends show that gray seal
abundance is likely increasing in the U.S. Atlantic EEZ (Waring et al.,
2017). Although the rate of increase is unknown, surveys conducted
since their arrival in the 1980s indicate a steady increase in
abundance in both Maine and Massachusetts (Waring et al., 2017). It is
believed that recolonization by Canadian gray seals is the source of
the U.S. population (Waring et al., 2017).
Since July 2018, elevated numbers of harbor seal and gray seal
mortalities have occurred across Maine, New Hampshire and
Massachusetts. This event has been declared a UME. Additionally, seals
showing clinical signs of stranding have occurred as far
[[Page 36063]]
south as Virginia, although not in elevated numbers. Therefore the UME
investigation now encompasses all seal strandings from Maine to
Virginia. Between July 1, 2018 and June 26, 2019, a total of 2,593 seal
strandings have been recorded as part of this designated Northeast
Pinniped UME. Based on tests conducted so far, the main pathogen found
in the seals is phocine distemper virus. Additional testing to identify
other factors that may be involved in this UME are underway.
Marine Mammal Hearing
Hearing is the most important sensory modality for marine mammals
underwater, and exposure to anthropogenic sound can have deleterious
effects. To appropriately assess the potential effects of exposure to
sound, it is necessary to understand the frequency ranges marine
mammals are able to hear. Current data indicate that not all marine
mammal species have equal hearing capabilities (e.g., Richardson et
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect
this, Southall et al. (2007) recommended that marine mammals be divided
into functional hearing groups based on directly measured or estimated
hearing ranges on the basis of available behavioral response data,
audiograms derived using auditory evoked potential techniques,
anatomical modeling, and other data. Note that no direct measurements
of hearing ability have been successfully completed for mysticetes
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described
generalized hearing ranges for these marine mammal hearing groups.
Generalized hearing ranges were chosen based on the approximately 65 dB
threshold from the normalized composite audiograms, with the exception
for lower limits for low-frequency cetaceans where the lower bound was
deemed to be biologically implausible and the lower bound from Southall
et al. (2007) retained. The functional groups and the associated
frequencies are indicated below (note that these frequency ranges
correspond to the range for the composite group, with the entire range
not necessarily reflecting the capabilities of every species within
that group):
Low-frequency cetaceans (mysticetes): Generalized hearing
is estimated to occur between approximately 7 Hertz (Hz) and 35 kHz;
Mid-frequency cetaceans (larger toothed whales, beaked
whales, and most delphinids): Generalized hearing is estimated to occur
between approximately 150 Hz and 160 kHz;
High-frequency cetaceans (porpoises, river dolphins, and
members of the genera Kogia and Cephalorhynchus; including two members
of the genus Lagenorhynchus, on the basis of recent echolocation data
and genetic data): Generalized hearing is estimated to occur between
approximately 275 Hz and 160 kHz.
Pinnipeds in water; Phocidae (true seals): Generalized
hearing is estimated to occur between approximately 50 Hz to 86 kHz;
Pinnipeds in water; Otariidae (eared seals): Generalized
hearing is estimated to occur between 60 Hz and 39 kHz.
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt,
2013).
For more detail concerning these groups and associated frequency
ranges, please see NMFS (2018) for a review of available information.
Fifteen marine mammal species (thirteen cetacean and two pinniped (both
phocid) species) have the reasonable potential to co-occur with the
proposed survey activities. Please refer to Table 2. Of the cetacean
species that may be present, five are classified as low-frequency
cetaceans (i.e., all mysticete species), seven are classified as mid-
frequency cetaceans (i.e., all delphinid species and the sperm whale),
and one is classified as high-frequency cetacean (i.e., harbor
porpoise).
Potential Effects of the Specified Activity on Marine Mammals and Their
Habitat
This section includes a summary and discussion of the ways that
components of the specified activity may impact marine mammals and
their habitat. The Estimated Take by Incidental Harassment section
later in this document includes a quantitative analysis of the number
of individuals that are expected to be taken by this activity. The
Negligible Impact Analysis and Determination section considers the
content of this section, the Estimated Take by Incidental Harassment
section, and the Proposed Mitigation section, to draw conclusions
regarding the likely impacts of these activities on the reproductive
success or survivorship of individuals and how those impacts on
individuals are likely to impact marine mammal species or stocks.
Background on Sound
Sound is a physical phenomenon consisting of minute vibrations that
travel through a medium, such as air or water, and is generally
characterized by several variables. Frequency describes the sound's
pitch and is measured in Hz or kHz, while sound level describes the
sound's intensity and is measured in dB. Sound level increases or
decreases exponentially with each dB of change. The logarithmic nature
of the scale means that each 10-dB increase is a 10-fold increase in
acoustic power (and a 20-dB increase is then a 100-fold increase in
power). A 10-fold increase in acoustic power does not mean that the
sound is perceived as being 10 times louder, however. Sound levels are
compared to a reference sound pressure (micro-Pascal) to identify the
medium. For air and water, these reference pressures are ``re: 20 micro
pascals ([micro]Pa)'' and ``re: 1 [micro]Pa,'' respectively. Root mean
square (RMS) is the quadratic mean sound pressure over the duration of
an impulse. RMS is calculated by squaring all of the sound amplitudes,
averaging the squares, and then taking the square root of the average
(Urick, 1975). RMS accounts for both positive and negative values;
squaring the pressures makes all values positive so that they may be
accounted for in the summation of pressure levels. This measurement is
often used in the context of discussing behavioral effects, in part
because behavioral effects, which often result from auditory cues, may
be better expressed through averaged units rather than by peak
pressures.
Acoustic Impacts
HRG survey equipment use during the geophysical surveys may
temporarily impact marine mammals in the area due to elevated in-water
sound levels. Marine mammals are continually exposed to many sources of
sound. Naturally occurring sounds such as lightning, rain, sub-sea
earthquakes, and biological sounds (e.g., snapping shrimp, whale songs)
are widespread throughout the world's oceans. Marine mammals produce
sounds in various contexts and use sound for various biological
functions including, but not limited to: (1) Social interactions; (2)
foraging; (3) orientation; and (4) predator detection. Interference
with producing or receiving these sounds may result in adverse impacts.
Audible distance, or received levels of sound depend on the nature of
the sound source, ambient noise conditions, and the sensitivity of the
receptor to the sound (Richardson et al., 1995). Type
[[Page 36064]]
and significance of marine mammal reactions to sound are likely
dependent on a variety of factors including, but not limited to, (1)
the behavioral state of the animal (e.g., feeding, traveling, etc.);
(2) frequency of the sound; (3) distance between the animal and the
source; and (4) the level of the sound relative to ambient conditions
(Southall et al., 2007).
When sound travels (propagates) from its source, its loudness
decreases as the distance traveled by the sound increases. Thus, the
loudness of a sound at its source is higher than the loudness of that
same sound a kilometer away. Acousticians often refer to the loudness
of a sound at its source (typically referenced to one meter from the
source) as the source level and the loudness of sound elsewhere as the
received level (i.e., typically the receiver). For example, a humpback
whale 3 km from a device that has a source level of 230 dB may only be
exposed to sound that is 160 dB loud, depending on how the sound
travels through water (e.g., spherical spreading (6 dB reduction with
doubling of distance) was used in this example). As a result, it is
important to understand the difference between source levels and
received levels when discussing the loudness of sound in the ocean or
its impacts on the marine environment.
As sound travels from a source, its propagation in water is
influenced by various physical characteristics, including water
temperature, depth, salinity, and surface and bottom properties that
cause refraction, reflection, absorption, and scattering of sound
waves. Oceans are not homogeneous and the contribution of each of these
individual factors is extremely complex and interrelated. The physical
characteristics that determine the sound's speed through the water will
change with depth, season, geographic location, and with time of day
(as a result, in actual active sonar operations, crews will measure
oceanic conditions, such as sea water temperature and depth, to
calibrate models that determine the path the sonar signal will take as
it travels through the ocean and how strong the sound signal will be at
a given range along a particular transmission path). As sound travels
through the ocean, the intensity associated with the wavefront
diminishes, or attenuates. This decrease in intensity is referred to as
propagation loss, also commonly called transmission loss.
Hearing Impairment
Marine mammals may experience temporary or permanent hearing
impairment when exposed to loud sounds. Hearing impairment is
classified by temporary threshold shift (TTS) and permanent threshold
shift (PTS). There are no empirical data for onset of PTS in any marine
mammal; therefore, PTS-onset must be estimated from TTS-onset
measurements and from the rate of TTS growth with increasing exposure
levels above the level eliciting TTS-onset. PTS is considered auditory
injury (Southall et al., 2007) and occurs in a specific frequency range
and amount. Irreparable damage to the inner or outer cochlear hair
cells may cause PTS; however, other mechanisms are also involved, such
as exceeding the elastic limits of certain tissues and membranes in the
middle and inner ears and resultant changes in the chemical composition
of the inner ear fluids (Southall et al., 2007). Given the higher level
of sound, longer durations of exposure necessary to cause PTS as
compared with TTS, and the small zone within which sound levels would
exceed criteria for onset of PTS, it is unlikely that PTS would occur
during the proposed HRG surveys.
Temporary Threshold Shift
TTS is the mildest form of hearing impairment that can occur during
exposure to a loud sound (Kryter, 1985). While experiencing TTS, the
hearing threshold rises and a sound must be stronger in order to be
heard. At least in terrestrial mammals, TTS can last from minutes or
hours to (in cases of strong TTS) days, can be limited to a particular
frequency range, and can occur to varying degrees (i.e., a loss of a
certain number of dBs of sensitivity). For sound exposures at or
somewhat above the TTS threshold, hearing sensitivity in both
terrestrial and marine mammals recovers rapidly after exposure to the
noise ends.
Marine mammal hearing plays a critical role in communication with
conspecifics and in interpretation of environmental cues for purposes
such as predator avoidance and prey capture. Depending on the degree
(elevation of threshold in dB), duration (i.e., recovery time), and
frequency range of TTS and the context in which it is experienced, TTS
can have effects on marine mammals ranging from discountable to
serious. For example, a marine mammal may be able to readily compensate
for a brief, relatively small amount of TTS in a non-critical frequency
range that takes place during a time when the animals is traveling
through the open ocean, where ambient noise is lower and there are not
as many competing sounds present. Alternatively, a larger amount and
longer duration of TTS sustained during a time when communication is
critical for successful mother/calf interactions could have more
serious impacts if it were in the same frequency band as the necessary
vocalizations and of a severity that it impeded communication. The fact
that animals exposed to levels and durations of sound that would be
expected to result in this physiological response would also be
expected to have behavioral responses of a comparatively more severe or
sustained nature is also notable and potentially of more importance
than the simple existence of a TTS.
Currently, TTS data only exist for four species of cetaceans
(bottlenose dolphin, beluga whale, harbor porpoise, and Yangtze finless
porpoise) and three species of pinnipeds (northern elephant seal,
harbor seal, and California sea lion) exposed to a limited number of
sound sources (i.e., mostly tones and octave-band noise) in laboratory
settings (e.g., Finneran et al., 2002 and 2010; Nachtigall et al.,
2004; Kastak et al., 2005; Lucke et al., 2009; Mooney et al., 2009;
Popov et al., 2011; Finneran and Schlundt, 2010). In general, harbor
seals (Kastak et al., 2005; Kastelein et al., 2012a) and harbor
porpoises (Lucke et al., 2009; Kastelein et al., 2012b) have a lower
TTS onset than other measured pinniped or cetacean species. However,
even for these animals, which are better able to hear higher
frequencies and may be more sensitive to higher frequencies, exposures
on the order of approximately 170 dBRMS or higher for brief
transient signals are likely required for even temporary (recoverable)
changes in hearing sensitivity that would likely not be categorized as
physiologically damaging (Lucke et al., 2009). Additionally, the
existing marine mammal TTS data come from a limited number of
individuals within these species. There are no data available on noise-
induced hearing loss for mysticetes (of note, the source operating
characteristics of some of Orsted's proposed HRG survey equipment--
i.e., the equipment positioning systems--are unlikely to be audible to
mysticetes). For summaries of data on TTS in marine mammals or for
further discussion of TTS onset thresholds, please see NMFS (2018),
Southall et al. (2007), Finneran and Jenkins (2012), and Finneran
(2015).
Scientific literature highlights the inherent complexity of
predicting TTS onset in marine mammals, as well as the importance of
considering exposure duration when assessing potential impacts (Mooney
et al., 2009a, 2009b; Kastak et al., 2007). Generally, with sound
exposures of equal energy,
[[Page 36065]]
quieter sounds (lower sound pressure level (SPL)) of longer duration
were found to induce TTS onset more than louder sounds (higher SPL) of
shorter duration (more similar to sub-bottom profilers). For
intermittent sounds, less threshold shift will occur than from a
continuous exposure with the same energy (some recovery will occur
between intermittent exposures) (Kryter et al., 1966; Ward, 1997). For
sound exposures at or somewhat above the TTS-onset threshold, hearing
sensitivity recovers rapidly after exposure to the sound ends;
intermittent exposures recover faster in comparison with continuous
exposures of the same duration (Finneran et al., 2010). NMFS considers
TTS as Level B harassment that is mediated by physiological effects on
the auditory system.
Marine mammals in the Survey Area during the HRG survey are
unlikely to incur TTS hearing impairment due to the characteristics of
the sound sources, which include low source levels (208 to 221 dB re 1
[micro]Pa-m) and generally very short pulses and duration of the sound.
Even for high-frequency cetacean species (e.g., harbor porpoises),
which may have increased sensitivity to TTS (Lucke et al., 2009;
Kastelein et al., 2012b), individuals would have to make a very close
approach and also remain very close to vessels operating these sources
in order to receive multiple exposures at relatively high levels, as
would be necessary to cause TTS. Intermittent exposures--as would occur
due to the brief, transient signals produced by these sources--require
a higher cumulative SEL to induce TTS than would continuous exposures
of the same duration (i.e., intermittent exposure results in lower
levels of TTS) (Mooney et al., 2009a; Finneran et al., 2010). Moreover,
most marine mammals would more likely avoid a loud sound source rather
than swim in such close proximity as to result in TTS. Kremser et al.
(2005) noted that the probability of a cetacean swimming through the
area of exposure when a sub-bottom profiler emits a pulse is small--
because if the animal was in the area, it would have to pass the
transducer at close range in order to be subjected to sound levels that
could cause temporary threshold shift and would likely exhibit
avoidance behavior to the area near the transducer rather than swim
through at such a close range. Further, the restricted beam shape of
the sub-bottom profiler and other HRG survey equipment makes it
unlikely that an animal would be exposed more than briefly during the
passage of the vessel. Boebel et al. (2005) concluded similarly for
single and multibeam echosounders, and more recently, Lurton (2016)
conducted a modeling exercise and concluded similarly that likely
potential for acoustic injury from these types of systems is
negligible, but that behavioral response cannot be ruled out. Animals
may avoid the area around the survey vessels, thereby reducing
exposure. Any disturbance to marine mammals is likely to be in the form
of temporary avoidance or alteration of opportunistic foraging behavior
near the survey location.
Masking
Masking is the obscuring of sounds of interest to an animal by
other sounds, typically at similar frequencies. Marine mammals are
highly dependent on sound, and their ability to recognize sound signals
amid other sound is important in communication and detection of both
predators and prey (Tyack, 2000). Background ambient sound may
interfere with or mask the ability of an animal to detect a sound
signal even when that signal is above its absolute hearing threshold.
Even in the absence of anthropogenic sound, the marine environment is
often loud. Natural ambient sound includes contributions from wind,
waves, precipitation, other animals, and (at frequencies above 30 kHz)
thermal sound resulting from molecular agitation (Richardson et al.,
1995).
Background sound may also include anthropogenic sound, and masking
of natural sounds can result when human activities produce high levels
of background sound. Conversely, if the background level of underwater
sound is high (e.g., on a day with strong wind and high waves), an
anthropogenic sound source would not be detectable as far away as would
be possible under quieter conditions and would itself be masked.
Ambient sound is highly variable on continental shelves (Thompson,
1965; Myrberg, 1978; Desharnais et al., 1999). This results in a high
degree of variability in the range at which marine mammals can detect
anthropogenic sounds.
Although masking is a phenomenon which may occur naturally, the
introduction of loud anthropogenic sounds into the marine environment
at frequencies important to marine mammals increases the severity and
frequency of occurrence of masking. For example, if a baleen whale is
exposed to continuous low-frequency sound from an industrial source,
this would reduce the size of the area around that whale within which
it can hear the calls of another whale. The components of background
noise that are similar in frequency to the signal in question primarily
determine the degree of masking of that signal. In general, little is
known about the degree to which marine mammals rely upon detection of
sounds from conspecifics, predators, prey, or other natural sources. In
the absence of specific information about the importance of detecting
these natural sounds, it is not possible to predict the impact of
masking on marine mammals (Richardson et al., 1995). In general,
masking effects are expected to be less severe when sounds are
transient than when they are continuous. Masking is typically of
greater concern for those marine mammals that utilize low-frequency
communications, such as baleen whales, and from sources of lower
frequency, because of how far low-frequency sounds propagate.
Marine mammal species, including ESA-listed species, that may be
exposed to survey noise are widely dispersed. As such, only a very
small percentage of the population is likely to be within the radius of
masking at any given time. Richardson et al. (1995) concludes broadly
that, although further data are needed, localized or temporary
increases in masking probably cause few problems for marine mammals,
with the possible exception of populations highly concentrated in an
ensonified area. While some number of marine mammals may be subject to
occasional masking as a result of survey activity, temporary shifts in
calling behavior to reduce the effects of masking, on the scale of no
more than a few minutes, are not likely to result in failure of an
animal to feed successfully, breed successfully, or complete its life
history.
Furthermore, marine mammal communications would not likely be
masked appreciably by sound from most HRG survey equipment given the
narrow beam widths, directionality of the signal, relatively small
ensonified area, and the brief period when an individual mammal is
likely to be exposed to sound from the HRG survey equipment.
Marine mammal communications would not likely be masked appreciably
by the sub-profiler or pingers' signals given the directionality of the
signal and the brief period when an individual mammal is likely to be
within its beam, as well as the higher frequencies.
Non-Auditory Physical Effects (Stress)
Classic stress responses begin when an animal's central nervous
system perceives a potential threat to its homeostasis. That perception
triggers stress responses regardless of whether a stimulus actually
threatens the animal; the mere perception of a threat is
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sufficient to trigger a stress response (Moberg, 2000; Seyle, 1950).
Once an animal's central nervous system perceives a threat, it mounts a
biological response or defense that consists of a combination of the
four general biological defense responses: Behavioral responses,
autonomic nervous system responses, neuroendocrine responses, or immune
responses.
In the case of many stressors, an animal's first and sometimes most
economical (in terms of biotic costs) response is behavioral avoidance
of the potential stressor or avoidance of continued exposure to a
stressor. An animal's second line of defense to stressors involves the
sympathetic part of the autonomic nervous system and the classical
``fight or flight'' response which includes the cardiovascular system,
the gastrointestinal system, the exocrine glands, and the adrenal
medulla to produce changes in heart rate, blood pressure, and
gastrointestinal activity that humans commonly associate with
``stress.'' These responses have a relatively short duration and may or
may not have significant long-term effect on an animal's welfare.
An animal's third line of defense to stressors involves its
neuroendocrine systems; the system that has received the most study has
been the hypothalamus-pituitary-adrenal system (also known as the HPA
axis in mammals or the hypothalamus-pituitary-interrenal axis in fish
and some reptiles). Unlike stress responses associated with the
autonomic nervous system, virtually all neuro-endocrine functions that
are affected by stress--including immune competence, reproduction,
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been
implicated in failed reproduction (Moberg, 1987; Rivier, 1995), altered
metabolism (Elasser et al., 2000), reduced immune competence (Blecha,
2000), and behavioral disturbance. Increases in the circulation of
glucocorticosteroids (cortisol, corticosterone, and aldosterone in
marine mammals; see Romano et al., 2004) have been equated with stress
for many years.
The primary distinction between stress (which is adaptive and does
not normally place an animal at risk) and distress is the biotic cost
of the response. During a stress response, an animal uses glycogen
stores that can be quickly replenished once the stress is alleviated.
In such circumstances, the cost of the stress response would not pose a
risk to the animal's welfare. However, when an animal does not have
sufficient energy reserves to satisfy the energetic costs of a stress
response, energy resources must be diverted from other biotic function,
which impairs those functions that experience the diversion. For
example, when mounting a stress response diverts energy away from
growth in young animals, those animals may experience stunted growth.
When mounting a stress response diverts energy from a fetus, an
animal's reproductive success and its fitness will suffer. In these
cases, the animals will have entered a pre-pathological or pathological
state which is called ``distress'' (Seyle, 1950) or ``allostatic
loading'' (McEwen and Wingfield, 2003). This pathological state will
last until the animal replenishes its biotic reserves sufficient to
restore normal function. Note that these examples involved a long-term
(days or weeks) stress response exposure to stimuli.
Relationships between these physiological mechanisms, animal
behavior, and the costs of stress responses have also been documented
fairly well through controlled experiments; because this physiology
exists in every vertebrate that has been studied, it is not surprising
that stress responses and their costs have been documented in both
laboratory and free-living animals (for examples see, Holberton et al.,
1996; Hood et al., 1998; Jessop et al., 2003; Krausman et al., 2004;
Lankford et al., 2005; Reneerkens et al., 2002; Thompson and Hamer,
2000). Information has also been collected on the physiological
responses of marine mammals to exposure to anthropogenic sounds (Fair
and Becker, 2000; Romano et al., 2002). For example, Rolland et al.
(2012) found that noise reduction from reduced ship traffic in the Bay
of Fundy was associated with decreased stress in North Atlantic right
whales. In a conceptual model developed by the Population Consequences
of Acoustic Disturbance (PCAD) working group, serum hormones were
identified as possible indicators of behavioral effects that are
translated into altered rates of reproduction and mortality.
Studies of other marine animals and terrestrial animals would also
lead us to expect some marine mammals to experience physiological
stress responses and, perhaps, physiological responses that would be
classified as ``distress'' upon exposure to high frequency, mid-
frequency and low-frequency sounds. For example, Jansen (1998) reported
on the relationship between acoustic exposures and physiological
responses that are indicative of stress responses in humans (for
example, elevated respiration and increased heart rates). Jones (1998)
reported on reductions in human performance when faced with acute,
repetitive exposures to acoustic disturbance. Trimper et al. (1998)
reported on the physiological stress responses of osprey to low-level
aircraft noise while Krausman et al. (2004) reported on the auditory
and physiology stress responses of endangered Sonoran pronghorn to
military overflights. Smith et al. (2004a, 2004b), for example,
identified noise-induced physiological transient stress responses in
hearing-specialist fish (i.e., goldfish) that accompanied short- and
long-term hearing losses. Welch and Welch (1970) reported physiological
and behavioral stress responses that accompanied damage to the inner
ears of fish and several mammals.
Hearing is one of the primary senses marine mammals use to gather
information about their environment and to communicate with
conspecifics. Although empirical information on the relationship
between sensory impairment (TTS, PTS, and acoustic masking) on marine
mammals remains limited, it seems reasonable to assume that reducing an
animal's ability to gather information about its environment and to
communicate with other members of its species would be stressful for
animals that use hearing as their primary sensory mechanism. Therefore,
we assume that acoustic exposures sufficient to trigger onset PTS or
TTS would be accompanied by physiological stress responses because
terrestrial animals exhibit those responses under similar conditions
(NRC, 2003). More importantly, marine mammals might experience stress
responses at received levels lower than those necessary to trigger
onset TTS. Based on empirical studies of the time required to recover
from stress responses (Moberg, 2000), we also assume that stress
responses are likely to persist beyond the time interval required for
animals to recover from TTS and might result in pathological and pre-
pathological states that would be as significant as behavioral
responses to TTS.
In general, there are few data on the potential for strong,
anthropogenic underwater sounds to cause non-auditory physical effects
in marine mammals. Such effects, if they occur at all, would presumably
be limited to short distances and to activities that extend over a
prolonged period. The available data do not allow identification of a
specific exposure level above which non-auditory effects can be
expected (Southall et al., 2007). There is no definitive evidence that
any
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of these effects occur even for marine mammals in close proximity to an
anthropogenic sound source. In addition, marine mammals that show
behavioral avoidance of survey vessels and related sound sources, are
unlikely to incur non-auditory impairment or other physical effects.
NMFS does not expect that the generally short-term, intermittent, and
transitory HRG surveys would create conditions of long-term, continuous
noise and chronic acoustic exposure leading to long-term physiological
stress responses in marine mammals.
Behavioral Disturbance
Behavioral responses to sound are highly variable and context-
specific. Many different variables can influence an animal's perception
of and response to (nature and magnitude) an acoustic event. An
animal's prior experience with a sound or sound source affects whether
it is less likely (habituation) or more likely (sensitization) to
respond to certain sounds in the future (animals can also be innately
pre-disposed to respond to certain sounds in certain ways) (Southall et
al., 2007). Related to the sound itself, the perceived nearness of the
sound, bearing of the sound (approaching vs. retreating), similarity of
a sound to biologically relevant sounds in the animal's environment
(i.e., calls of predators, prey, or conspecifics), and familiarity of
the sound may affect the way an animal responds to the sound (Southall
et al., 2007, DeRuiter et al., 2013). Individuals (of different age,
gender, reproductive status, etc.) among most populations will have
variable hearing capabilities, and differing behavioral sensitivities
to sounds that will be affected by prior conditioning, experience, and
current activities of those individuals. Often, specific acoustic
features of the sound and contextual variables (i.e., proximity,
duration, or recurrence of the sound or the current behavior that the
marine mammal is engaged in or its prior experience), as well as
entirely separate factors such as the physical presence of a nearby
vessel, may be more relevant to the animal's response than the received
level alone. Studies by DeRuiter et al. (2012) indicate that
variability of responses to acoustic stimuli depends not only on the
species receiving the sound and the sound source, but also on the
social, behavioral, or environmental contexts of exposure.
Ellison et al. (2012) outlined an approach to assessing the effects
of sound on marine mammals that incorporates contextual-based factors.
The authors recommend considering not just the received level of sound,
but also the activity the animal is engaged in at the time the sound is
received, the nature and novelty of the sound (i.e., is this a new
sound from the animal's perspective), and the distance between the
sound source and the animal. They submit that this ``exposure
context,'' as described, greatly influences the type of behavioral
response exhibited by the animal. This sort of contextual information
is challenging to predict with accuracy for ongoing activities that
occur over large spatial and temporal expanses. However, distance is
one contextual factor for which data exist to quantitatively inform a
take estimate. Other factors are often considered qualitatively in the
analysis of the likely consequences of sound exposure, where supporting
information is available.
Exposure of marine mammals to sound sources can result in, but is
not limited to, no response or any of the following observable
response: Increased alertness; orientation or attraction to a sound
source; vocal modifications; cessation of feeding; cessation of social
interaction; alteration of movement or diving behavior; habitat
abandonment (temporary or permanent); and, in severe cases, panic,
flight, stranding, potentially resulting in death (Southall et al.,
2007). A review of marine mammal responses to anthropogenic sound was
first conducted by Richardson (1995). More recent reviews (Nowacek et
al.,2007; DeRuiter et al., 2012 and 2013; Ellison et al., 2012) address
studies conducted since 1995 and focused on observations where the
received sound level of the exposed marine mammal(s) was known or could
be estimated. Southall et al. (2016) states that results demonstrate
that some individuals of different species display clear yet varied
responses, some of which have negative implications, while others
appear to tolerate high levels, and that responses may not be fully
predicable with simple acoustic exposure metrics (e.g., received sound
level). Rather, the authors state that differences among species and
individuals along with contextual aspects of exposure (e.g., behavioral
state) appear to affect response probability.
Changes in dive behavior can vary widely. They may consist of
increased or decreased dive times and surface intervals as well as
changes in the rates of ascent and descent during a dive. Variations in
dive behavior may reflect interruptions in biologically significant
activities (e.g., foraging) or they may be of little biological
significance. Variations in dive behavior may also expose an animal to
potentially harmful conditions (e.g., increasing the chance of ship-
strike) or may serve as an avoidance response that enhances
survivorship. The impact of a variation in diving resulting from an
acoustic exposure depends on what the animal is doing at the time of
the exposure and the type and magnitude of the response.
Avoidance is the displacement of an individual from an area as a
result of the presence of a sound. Richardson et al. (1995) noted that
avoidance reactions are the most obvious manifestations of disturbance
in marine mammals. Avoidance is qualitatively different from the flight
response, but also differs in the magnitude of the response (i.e.,
directed movement, rate of travel, etc.). Oftentimes avoidance is
temporary, and animals return to the area once the noise has ceased.
However, longer term displacement is possible and can lead to changes
in abundance or distribution patterns of the species in the affected
region if they do not become acclimated to the presence of the sound
(Blackwell et al., 2004; Bejder et al., 2006; Teilmann et al., 2006).
Acute avoidance responses have been observed in captive porpoises and
pinnipeds exposed to a number of different sound sources (Kastelein et
al., 2001; Finneran et al., 2003; Kastelein et al., 2006a; Kastelein et
al., 2006b).
Southall et al. (2007) reviewed the available literature on marine
mammal hearing and behavioral and physiological responses to human-made
sound with the goal of proposing exposure criteria for certain effects.
This peer-reviewed compilation of literature is very valuable, though
Southall et al. (2007) note that not all data are equal, some have poor
statistical power, insufficient controls, and/or limited information on
received levels, background noise, and other potentially important
contextual variables--such data were reviewed and sometimes used for
qualitative illustration but were not included in the quantitative
analysis for the criteria recommendations. All of the studies
considered, however, contain an estimate of the received sound level
when the animal exhibited the indicated response.
For purposes of analyzing responses of marine mammals to
anthropogenic sound and developing criteria, NMFS (2018) differentiates
between pulse (impulsive) sounds (single and multiple) and non-pulse
sounds. For purposes of evaluating the potential for take of marine
mammals resulting from underwater noise due to the conduct of the
proposed HRG surveys (operation of USBL positioning system and the sub-
bottom profilers), the criteria for Level A harassment (PTS onset) from
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impulsive noise was used as prescribed in NMFS (2018) and the threshold
level for Level B harassment (160 dBRMS re 1 [micro]Pa) was
used to evaluate takes from behavioral harassment.
Studies that address responses of low-frequency cetaceans to sounds
include data gathered in the field and related to several types of
sound sources, including: Vessel noise, drilling and machinery
playback, low-frequency M-sequences (sine wave with multiple phase
reversals) playback, tactical low-frequency active sonar playback,
drill ships, and non-pulse playbacks. These studies generally indicate
no (or very limited) responses to received levels in the 90 to 120 dB
re: 1[micro]Pa range and an increasing likelihood of avoidance and
other behavioral effects in the 120 to 160 dB range. As mentioned
earlier, though, contextual variables play a very important role in the
reported responses and the severity of effects do not increase linearly
with received levels. Also, few of the laboratory or field datasets had
common conditions, behavioral contexts, or sound sources, so it is not
surprising that responses differ.
The studies that address responses of mid-frequency cetaceans to
sounds include data gathered both in the field and the laboratory and
related to several different sound sources, including: Pingers,
drilling playbacks, ship and ice-breaking noise, vessel noise, Acoustic
harassment devices (AHDs), Acoustic Deterrent Devices (ADDs), mid-
frequency active sonar, and non-pulse bands and tones. Southall et al.
(2007) were unable to come to a clear conclusion regarding the results
of these studies. In some cases animals in the field showed significant
responses to received levels between 90 and 120 dB, while in other
cases these responses were not seen in the 120 to 150 dB range. The
disparity in results was likely due to contextual variation and the
differences between the results in the field and laboratory data
(animals typically responded at lower levels in the field). The studies
that address the responses of mid-frequency cetaceans to impulse sounds
include data gathered both in the field and the laboratory and related
to several different sound sources, including: Small explosives, airgun
arrays, pulse sequences, and natural and artificial pulses. The data
show no clear indication of increasing probability and severity of
response with increasing received level. Behavioral responses seem to
vary depending on species and stimuli.
The studies that address responses of high-frequency cetaceans to
sounds include data gathered both in the field and the laboratory and
related to several different sound sources, including: Pingers, AHDs,
and various laboratory non-pulse sounds. All of these data were
collected from harbor porpoises. Southall et al. (2007) concluded that
the existing data indicate that harbor porpoises are likely sensitive
to a wide range of anthropogenic sounds at low received levels (around
90 to 120 dB), at least for initial exposures. All recorded exposures
above 140 dB induced profound and sustained avoidance behavior in wild
harbor porpoises (Southall et al., 2007). Rapid habituation was noted
in some but not all studies.
The studies that address the responses of pinnipeds in water to
sounds include data gathered both in the field and the laboratory and
related to several different sound sources, including: AHDs, various
non-pulse sounds used in underwater data communication, underwater
drilling, and construction noise. Few studies exist with enough
information to include them in the analysis. The limited data suggest
that exposures to non-pulse sounds between 90 and 140 dB generally do
not result in strong behavioral responses of pinnipeds in water, but no
data exist at higher received levels (Southall et al., 2007). The
studies that address the responses of pinnipeds in water to impulse
sounds include data gathered in the field and related to several
different sources, including: Small explosives, impact pile driving,
and airgun arrays. Quantitative data on reactions of pinnipeds to
impulse sounds is limited, but a general finding is that exposures in
the 150 to 180 dB range generally have limited potential to induce
avoidance behavior (Southall et al., 2007).
Sound can disrupt behavior through masking, or interfering with, an
animal's ability to detect, recognize, or discriminate between acoustic
signals of interest (e.g., those used for intraspecific communication
and social interactions, prey detection, predator avoidance,
navigation) (Richardson et al., 1995; Erbe and Farmer, 2000; Tyack,
2000; Erbe et al., 2016). Masking occurs when the receipt of a sound is
interfered with by another coincident sound at similar frequencies and
at similar or higher intensity, and may occur whether the sound is
natural (e.g., snapping shrimp, wind, waves, precipitation) or
anthropogenic (e.g., shipping, sonar, seismic exploration) in origin.
The ability of a noise source to mask biologically important sounds
depends on the characteristics of both the noise source and the signal
of interest (e.g., signal-to-noise ratio, temporal variability,
direction), in relation to each other and to an animal's hearing
abilities (e.g., sensitivity, frequency range, critical ratios,
frequency discrimination, directional discrimination, age or TTS
hearing loss), and existing ambient noise and propagation conditions.
Masking these acoustic signals can disturb the behavior of individual
animals, groups of animals, or entire populations. Under certain
circumstances, marine mammals experiencing significant masking could
also be impaired from maximizing their performance fitness in survival
and reproduction. Therefore, when the coincident (masking) sound is
man-made, it may be considered harassment when disrupting or altering
critical behaviors. The frequency range of the potentially masking
sound is important in determining any potential behavioral impacts. For
example, low-frequency signals may have less effect on high-frequency
echolocation sounds produced by odontocetes but are more likely to
affect detection of mysticete communication calls and other potentially
important natural sounds such as those produced by surf and some prey
species. The masking of communication signals by anthropogenic noise
may be considered as a reduction in the communication space of animals
(e.g., Clark et al., 2009; Matthews et al., 2016) and may result in
energetic or other costs as animals change their vocalization behavior
(e.g.,Miller et al., 2000; Foote et al., 2004; Parks et al., 2007; Di
Iorio and Clark, 2009; Holt et al., 2009).
Marine mammals are likely to avoid the HRG survey activity,
especially harbor porpoises, while the harbor seals might be attracted
to them out of curiosity. However, because the sub-bottom profilers and
other HRG survey equipment operate from a moving vessel, and the
predicted maximum distance to the 160 dBRMS re 1[micro]Pa
isopleth (Level B harassment criteria) is 178 m, the area and time that
this equipment would be affecting a given location is very small.
Further, once an area has been surveyed, it is not likely that it will
be surveyed again, therefore reducing the likelihood of repeated HRG-
related impacts within the survey area.
A number of cetacean mass stranding events have been linked to use
of military active sonar. We considered the potential for HRG equipment
to result in standings or indirect injury or mortality based on the
2008 mass stranding of approximately one hundred melon-headed whales in
a Madagascar lagoon system. An investigation of the event indicated
that use of a high-frequency
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mapping system (12-kHz multibeam echosounder) was the most plausible
and likely initial behavioral trigger of the event, while providing the
caveat that there is no unequivocal and easily identifiable single
cause (Southall et al., 2013). The investigatory panel's conclusion was
based on (1) very close temporal and spatial association and directed
movement of the survey with the stranding event; (2) the unusual nature
of such an event coupled with previously documented apparent behavioral
sensitivity of the species to other sound types (Southall et al., 2006;
Brownell et al., 2009); and (3) the fact that all other possible
factors considered were determined to be unlikely causes. Specifically,
regarding survey patterns prior to the event and in relation to
bathymetry, the vessel transited in a north-south direction on the
shelf break parallel to the shore, ensonifying large areas of deep-
water habitat prior to operating intermittently in a concentrated area
offshore from the stranding site; this may have trapped the animals
between the sound source and the shore, thus driving them towards the
lagoon system. The investigatory panel systematically excluded or
deemed highly unlikely nearly all potential reasons for these animals
leaving their typical pelagic habitat for an area extremely atypical
for the species (i.e., a shallow lagoon system). Notably, this was the
first time that such a system has been associated with a stranding
event. The panel also noted several site- and situation-specific
secondary factors that may have contributed to the avoidance responses
that led to the eventual entrapment and mortality of the whales.
Specifically, shoreward-directed surface currents and elevated
chlorophyll levels in the area preceding the event may have played a
role (Southall et al., 2013). The report also notes that prior use of a
similar system in the general area may have sensitized the animals and
also concluded that, for odontocete cetaceans that hear well in higher
frequency ranges where ambient noise is typically quite low, high-power
active sonars operating in this range may be more easily audible and
have potential effects over larger areas than low frequency systems
that have more typically been considered in terms of anthropogenic
noise impacts. It is, however, important to note that the relatively
lower output frequency, higher output power, and complex nature of the
system implicated in this event, in context of the other factors noted
here, likely produced a fairly unusual set of circumstances that
indicate that such events would likely remain rare and are not
necessarily relevant to use of lower-power, higher-frequency systems
more commonly used for HRG survey applications. The risk of similar
events recurring may be very low, given the extensive use of active
acoustic systems used for scientific and navigational purposes
worldwide on a daily basis and the lack of direct evidence of such
responses previously reported.
Tolerance
Numerous studies have shown that underwater sounds from industrial
activities are often readily detectable by marine mammals in the water
at distances of many kilometers. However, other studies have shown that
marine mammals at distances more than a few kilometers away often show
no apparent response to industrial activities of various types (Miller
et al., 2005). This is often true even in cases when the sounds must be
readily audible to the animals based on measured received levels and
the hearing sensitivity of that mammal group. Although various baleen
whales, toothed whales, and (less frequently) pinnipeds have been shown
to react behaviorally to underwater sound from sources such as airgun
pulses or vessels under some conditions, at other times, mammals of all
three types have shown no overt reactions (e.g., Malme et al., 1986;
Richardson et al., 1995; Madsen and Mohl, 2000; Croll et al., 2001;
Jacobs and Terhune, 2002; Madsen et al., 2002; Miller et al., 2005). In
general, pinnipeds seem to be more tolerant of exposure to some types
of underwater sound than are baleen whales. Richardson et al. (1995)
found that vessel sound does not seem to strongly affect pinnipeds that
are already in the water. Richardson et al. (1995) went on to explain
that seals on haulouts sometimes respond strongly to the presence of
vessels and at other times appear to show considerable tolerance of
vessels, and Brueggeman et al. (1992) observed ringed seals (Pusa
hispida) hauled out on ice pans displaying short-term escape reactions
when a ship approached within 0.16-0.31 mi (0.25-0.5 km). Due to the
relatively high vessel traffic in the Survey Area it is possible that
marine mammals are habituated to noise from project vessels in the
area.
Vessel Strike
Ship strikes of marine mammals can cause major wounds, which may
lead to the death of the animal. An animal at the surface could be
struck directly by a vessel, a surfacing animal could hit the bottom of
a vessel, or a vessel's propeller could injure an animal just below the
surface. The severity of injuries typically depends on the size and
speed of the vessel (Knowlton and Kraus, 2001; Laist et al., 2001).
The most vulnerable marine mammals are those that spend extended
periods of time at the surface in order to restore oxygen levels within
their tissues after deep dives (e.g., the sperm whale). In addition,
some baleen whales, such as the North Atlantic right whale, seem
generally unresponsive to vessel sound, making them more susceptible to
vessel collisions (Nowacek et al., 2004). These species are primarily
large, slow moving whales. Smaller marine mammals (e.g., bottlenose
dolphin) move quickly through the water column and are often seen
riding the bow wave of large ships. Marine mammal responses to vessels
may include avoidance and changes in dive pattern (NRC, 2003).
An examination of all known ship strikes from all shipping sources
(civilian and military) indicates vessel speed is a principal factor in
whether a vessel strike results in death (Knowlton and Kraus, 2001;
Laist et al., 2001; Jensen and Silber, 2003; Vanderlaan and Taggart,
2007). In assessing records with known vessel speeds, Laist et al.
(2001) found a direct relationship between the occurrence of a whale
strike and the speed of the vessel involved in the collision. The
authors concluded that most deaths occurred when a vessel was traveling
in excess of 24.1 km/h (14.9 mph; 13 knots). Given the slow vessel
speeds and predictable course necessary for data acquisition, ship
strike is unlikely to occur during the geophysical and geotechnical
surveys. Most marine mammals would be able to easily avoid vessels and
are likely already habituated to the presence of numerous vessels in
the area. Further, Orsted shall implement measures (e.g., vessel speed
restrictions and separation distances; see Proposed Mitigation
Measures) set forth in the BOEM Lease to reduce the risk of a vessel
strike to marine mammal species in the Survey Area. Finally, survey
vessels will travel at slow speeds (approximately 4 knots) during the
survey, which reduces the risk of injury in the unlikely the event a
survey vessel strikes a marine mammal.
Effects on Marine Mammal Habitat
Bottom disturbance associated with the HRG activities may include
grab sampling to validate the seabed classification obtained from the
multibeam echosounder/sidescan sonar data. This will typically be
accomplished using a Mini-Harmon Grab with 0.1 m\2\ sample area or the
[[Page 36070]]
slightly larger Harmon Grab with a 0.2 m\2\ sample area. This limited
and highly localized impact to habitat in relation to the comparatively
vast area of surrounding open ocean, would not be expected to result in
any effects to prey availability. The HRG survey equipment itself will
not disturb the seafloor.
There are no feeding areas, rookeries, or mating grounds known to
be biologically important to marine mammals within the proposed project
area with the exception of a feeding BIA for fin whales and migratory
BIA for North Atlantic right whales which were described previously.
There is also no designated critical habitat for any ESA-listed marine
mammals. NMFS' regulations at 50 CFR part 224 designated the nearshore
waters of the Mid-Atlantic Bight as the Mid-Atlantic U.S. Seasonal
Management Area (SMA) for right whales in 2008. Mandatory vessel speed
restrictions are in place in that SMA from November 1 through April 30
to reduce the threat of collisions between ships and right whales
around their migratory route and calving grounds.
We are not aware of any available literature on impacts to marine
mammal prey species from HRG survey equipment. However, because the HRG
survey equipment introduces noise to the marine environment, there is
the potential for avoidance of the area around the HRG survey
activities by marine mammal prey species. Any avoidance of the area on
the part of marine mammal prey species would be expected to be short
term and temporary. Because of the temporary nature of the disturbance,
the availability of similar habitat and resources (e.g.,prey species)
in the surrounding area, and the lack of important or unique marine
mammal habitat, 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.
Impacts on marine mammal habitat from the proposed activities will be
temporary, insignificant, and discountable.
Estimated Take
This section provides an estimate of the number of incidental takes
proposed for authorization through this IHA, which will inform both
NMFS' consideration of ``small numbers'' and the negligible impact
determination.
Harassment is the only type of take expected to result from these
activities. Except with respect to certain activities not pertinent
here, 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 sound from HRG equipment. Based on the
nature of the activity and the anticipated effectiveness of the
mitigation measures (i.e., shutdown--discussed in detail below in
Proposed Mitigation section), Level A harassment is neither anticipated
nor proposed to be authorized.
As described previously, no mortality is anticipated or proposed to
be authorized for this activity. Below we describe how the take is
estimated.
Generally speaking, we estimate take by considering: (1) Acoustic
thresholds above which NMFS believes the best available science
indicates marine mammals will be behaviorally harassed or incur some
degree of permanent hearing impairment; (2) the area or volume of water
that will be ensonified above these levels in a day; (3) the density or
occurrence of marine mammals within these ensonified areas; and, (4)
and the number of days of activities. We note that while these basic
factors can contribute to a basic calculation to provide an initial
prediction of takes, additional information that can qualitatively
inform take estimates is also sometimes available (e.g., previous
monitoring results or average group size). Below, we describe the
factors considered here in more detail and present the proposed take
estimate.
Acoustic Thresholds
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 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., 2011). 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 120 dB re 1 [mu]Pa (rms) for continuous (e.g.,
vibratory pile-driving, drilling) and above 160 dB re 1 [mu]Pa (rms)
for non-explosive impulsive (e.g., seismic airguns) or intermittent
(e.g., scientific sonar) sources. Orsted's proposed activities include
the use of intermittent impulsive (HRG Equipment) sources, and
therefore 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 (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).
These thresholds are provided in Table 4 below. The references,
analysis, and methodology used in the development of the thresholds are
described in NMFS 2018 Technical Guidance, which may be accessed at:
http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.
[[Page 36071]]
Table 4--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
PTS onset acoustic thresholds * (received level)
Hearing group ------------------------------------------------------------------------
Impulsive Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans........... Cell 1: Lpk,flat: 219 dB; Cell 2: LE,LF,24h: 199 dB.
LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans........... Cell 3: Lpk,flat: 230 dB; Cell 4: LE,MF,24h: 198 dB.
LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans.......... Cell 5: Lpk,flat: 202 dB; Cell 6: LE,HF,24h: 173 dB.
LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater)..... Cell 7: Lpk,flat: 218 dB; Cell 8: LE,PW,24h: 201 dB.
LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater).... Cell 9: Lpk,flat: 232 dB; Cell 10: LE,OW,24h: 219 dB.
LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [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.
When NMFS' Acoustic Technical Guidance (2016) was published, in
recognition of the fact that ensonified area/volume could be more
technically challenging to predict because of the duration component of
the new thresholds, NMFS developed an optional User Spreadsheet that
includes tools to help predict takes. We note that because of some of
the assumptions included in the methods used for these tools, we
anticipate that isopleths produced are typically going to be
overestimates of some degree, which will result in some degree of
overestimate of Level A take. However, these tools offer the best way
to predict appropriate isopleths when more sophisticated 3D modeling
methods are not available, and NMFS continues to develop ways to
quantitatively refine these tools, and will qualitatively address the
output where appropriate. For mobile sources such as the HRG survey
equipment proposed for use in Orsted's activity, the User Spreadsheet
predicts the closest distance at which a stationary animal would not
incur PTS if the sound source traveled by the animal in a straight line
at a constant speed.
Orsted conducted field verification tests on different types of HRG
equipment within the proposed Lease Areas during previous site
characterization survey activities. NMFS is proposing to authorize take
in these same three Lease Areas listed below.
OCS-A 0486 & OCS-A 0487: Marine Acoustics, Inc. (MAI),
under contract to Oceaneering International completed an underwater
noise monitoring program for the field verification for equipment to be
used to survey the Skipjack Windfarm Project (MAI 2018a; 2018b).
OCS-A 0500 Lease Area: The Gardline Group (Gardline),
under contract to Alpine Ocean Seismic Survey, Inc., completed an
underwater noise monitoring program for the field verification within
the Lease Area prior to the commencement of the HRG survey which took
place between August 14 and October 6, 2016 (Gardline 2016a, 2016b,
2017). Additional field verifications were completed by the RPS Group,
under contract to Terrasond prior to commencement of the 2018 HRG field
survey campaign (RPS 2018).
Field Verification results are shown in Table 5. The purpose of the
field verification programs was to determine distances to the
regulatory thresholds for injury/mortality and behavior disturbance of
marine mammals that were established during the permitting process.
As part of their application, Orsted collected field verified
source levels and calculated the differential between the averaged
measured field verified source levels versus manufacturers' reported
source levels for each tested piece of HRG equipment. The results of
the field verification studies were used to derive the variability in
source levels based on the extrapolated values resulting from
regression analysis. These values were used to further calibrate
calculations for a specific suite of HRG equipment of similar type.
Orsted stated that the calculated differential accounts for both the
site specific environmental conditions and directional beam width
patterns and can be applied to similar HRG equipment within one of the
specified equipment categories (e.g., USBL & GAPS Transceivers, Shallow
Sub-Bottom Profilers (SBP), Parametric SBP, Medium Penetration SBP
(Sparker), and Medium Penetration SBP (Boomer)). For example, the
manufacturer of the Geosource 800J medium penetration SBP reported a
source level of 206 dB RMS. The field verification study measured a
source level of 189 dB RMS (Gardline 2016a, 2017). Therefore, the
differential between the manufacturer and field verified SL is -17 dB
RMS. Orsted proposed to apply this differential (-17 dB) to other HRG
equipment in the medium penetration SBP (sparker) category with an
output of approximately 800 joules. Orsted employed this methodology
for all non-field verified equipment within a specific equipment
category. These new differential-based proxy SLs were inserted into the
User Spreadsheet and used to calculate the Level A and Level B
harassment isopleths for the various hearing groups. Table 5 shows the
field verified equipment SSV results as well as applicable non-verified
equipment broken out by equipment category.
[[Page 36072]]
Table 5--Summary of Field Verified HRG Equipment SSV Results and Applicable HRG Devices Grouped by Category Type
----------------------------------------------------------------------------------------------------------------
Source level
Baseline source measured during
Representative HRG survey Operating level (dB re 1 [Oslash]rsted FV 2019 HRG survey data
equipment frequencies [mu]Pa) surveys (dB re 1 acquisition equipment
[mu]Pa)
----------------------------------------------------------------------------------------------------------------
USBL & GAPS Transponder and Transceiver a
----------------------------------------------------------------------------------------------------------------
Sonardyne Ranger 2............. 19 to 34 kHz..... 200 dBRMS........ 166 dBRMS........ Sonardyne Ranger 2
USBL HPT 5/7000;
Sonardyne Ranger 2
USBL HPT 3000;
Sonardyne Scout Pro;
Easytrak Nexus 2
USBL; IxSea GAPS
System; Kongsberg
HiPAP 501/502 USBL;
Edgetech BATS II.
----------------------------------------------------------------------------------------------------------------
Shallow Sub-Bottom Profilers (Chirp) a c
----------------------------------------------------------------------------------------------------------------
GeoPulse 5430 A Sub-bottom 1.5 to 18 kHz.... 214 dBRMS........ 173 dBRMS........ Edgetech 3200;
Profiler. Teledyne Benthos
Chirp III--TTV 170.
EdgeTech 512................... 0.5 to 12 kHz.... 177 dBRMS........ 166 dBRMS........ PanGeo LF Chirp;
PanGeo HF Chirp;
EdgeTech 216;
EdgeTech 424.
----------------------------------------------------------------------------------------------------------------
Parametric Sub-Bottom Profiler d
----------------------------------------------------------------------------------------------------------------
Innomar SES-2000 Medium 100.... 85 to 115........ 247 dBRMS........ 187 dBRMS........ Innomar SES-2000
Standard & Plus;
Innomar SES-2000
Medium 70; Innomar
SES-2000 Quattro;
PanGeo 2i Parametric.
----------------------------------------------------------------------------------------------------------------
Medium Penetration Sub-Bottom Profiler (Sparker) a
----------------------------------------------------------------------------------------------------------------
Geo-Resources Geo-Source 600 J. 0.05 to 5 kHz.... 214 dBPeak; 205 206 dBPeak; 183 GeoMarine Geo-Source
dBRMS. dBRMS. 400tip; Applied
Acoustics Dura-Spark
400 System.
Geo-Resources Geo-Source 800 J. 0.05 to 5 kHz.... 215 dBPeak; 206 212 dBPeak; 189 GeoMarine Geo-Source
dBRMS. dBRMS. 800.
----------------------------------------------------------------------------------------------------------------
Medium Penetration Sub-Bottom Profiler (Boomer) b c
----------------------------------------------------------------------------------------------------------------
Applied Acoustics S-Boom Triple 0.1 to 5......... 211 dBPeak; 205 195 dBPeak; 173 Not used for any other
Plate Boomer (700J). dBRMS. dBRMS. equipment.
Applied Acoustics S-Boom Triple 0.250 to 8 kHz... 228 dBPeak; 208 215 dBPeak; 198 Not used for any other
Plate Boomer (1000J). dBRMS. dBRMS. equipment.
----------------------------------------------------------------------------------------------------------------
Sources: a Gardline 2016a, 2017; b RPS 2018; c MAI 2018a; d Subacoustech 2018
After careful consideration, NMFS concluded that the use of
differentials to derive proxy SLs is not appropriate or acceptable.
NMFS determined that when field verified measurements are compared to
the source levels measured in a controlled experimental setting (i.e.,
Crocker and Fratantonio, 2016), there are significant discrepancies in
isopleth distances for the same equipment that cannot be explained
solely by absorption and scattering of acoustic energy. There are a
number of variables, including potential differences in propagation
rate, operating frequency, beam width, and pulse width that make us
question whether SL differential values can be universally applied
across different pieces of equipment, even if they fall within the same
equipment category. Therefore, NMFS did not employ Orsted's proposed
use of differentials to determine Level A and Level B harassment
isopleths or proposed take estimates.
As noted above, much of the HRG equipment proposed for use during
Orsted's survey has not been field-verified. NMFS employed an alternate
approach in which data reported by Crocker and Fratantonio (2016) was
used to establish injury and behavioral harassment zones. If Crocker
and Fratantonio (2016) did not provide data on a specific piece of
equipment within a given equipment category, the SLs reported in the
study for measured equipment are used to represent all the other
equipment within that category, regardless of whether any of the
devices has been field verified. If SSV data from Crocker and
Fratantonio (2016) is not available across an entire equipment
category, NMFS instead adopted the field verified results from
equipment that had been tested. Here, the largest field verified SL was
used to represent the entire equipment category. These values were
applied to the User Spreadsheet to calculate distances for each of the
proposed HRG equipment categories that might result in harassment of
marine mammals. Inputs to the User Spreadsheet are shown in Table 6.
The source levels used in Table 6 are from field verified values shown
in Table 5. However, source levels for the EdgeTech 512 (177 dB RMS)
and Applied Acoustics S-Boom Triple Plate Boomer (1,000j) (203 dB RMS)
were derived from Crocker and Fratantonio (2016). Table 7 depicts
isopleths that could result in injury to a specific hearing group.
Table 6--Inputs to the User Spreadsheet
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
USBL Shallow penetration SBP- Shallow penetration SBP- Parametric SBP Medium penetration SBP-- Medium penetration SBP--
--------------------------- chirp chirp -------------------------- sparker boomer
Spreadsheet tab used ------------------------------------------------------ ---------------------------------------------------
D: Mobile source: Non- D: Mobile source: Non- D: Mobile source: Non- D: Mobile source: Non- F: Mobile source: F: Mobile source:
impulsive, intermittent impulsive, intermittent impulsive, intermittent impulsive, intermittent impulsive, intermittent impulsive, intermittent
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
HRG Equipment.................... Sonardyne Ranger 2....... GeoPulse 5430 A Sub- EdgeTech 512............. Innomar SES 2000 Medium GeoMarine Geo-Source 800 Applied Acoustics S-Boom
bottom Profiler. 100. J. Triple Plate Boomer
(1,000j).
[[Page 36073]]
Source Level (dB RMS SPL)........ 166...................... 173...................... 177 *.................... 187..................... 212 Pk; 189 RMS......... 209 Pk; 203 RMS.*
Weighting Factor Adjustment (kHz) 26....................... 4.5...................... 3........................ 42...................... 2....................... 0.6.
Source Velocity (m/s)............ 2.045.................... 2.045.................... 2.045.................... 2.045................... 2.045................... 2.045.
Pulse Duration (seconds)......... 0.3...................... 0.025.................... 0.0022................... 0.001................... 0.055................... 0.0006.
1/Repetition rate [caret] 1........................ 0.1...................... 0.50..................... 0.025................... 0.5..................... 0.333.
(seconds).
Source Level (PK SPL)............ ......................... ......................... ......................... ........................ 212..................... 215.
Propagation (xLogR).............. 20....................... 20....................... 20....................... 20...................... 20...................... 20.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
* Crocker and Fratantonio (2016).
Table 7--Maximum Distances to Level A Harassment Isopleths Based on Data From Field Verification Studies and
Crocker and Fratantonio (2016) (Where Available)
----------------------------------------------------------------------------------------------------------------
Lateral
Representative HRG survey equipment Marine mammal group PTS onset distance
(m)
----------------------------------------------------------------------------------------------------------------
USBL/GAPS Positioning Systems
----------------------------------------------------------------------------------------------------------------
Sonardyne Ranger 2....................... LF cetaceans................ 199 dB SELcum............... .........
MF cetaceans................ 198 dB SELcum............... .........
HF cetaceans................ 173 dB SELcum............... <1
Phocid pinnipeds............ 201 dB SELcum............... .........
----------------------------------------------------------------------------------------------------------------
Shallow Sub-Bottom Profiler (Chirp)
----------------------------------------------------------------------------------------------------------------
Edgetech 512............................. LF cetaceans................ 199 dB SELcum............... .........
MF cetaceans................ 198 dB SELcum............... .........
HF cetaceans................ 173 dB SELcum............... .........
Phocid pinnipeds............ 201 dB SELcum............... .........
GeoPulse 5430 A Sub-bottom Profiler...... LF cetaceans................ 199 dB SELcum............... .........
MF cetaceans................ 198 dB SELcum............... .........
HF cetaceans................ 173 dB SELcum............... .........
Phocid pinnipeds............ 201 dB SELcum............... .........
----------------------------------------------------------------------------------------------------------------
Parametric Sub-bottom Profiler
----------------------------------------------------------------------------------------------------------------
Innomar SES-2000 Medium 100.............. LF cetaceans................ 199 dB SELcum............... .........
MF cetaceans................ 198 dB SELcum............... .........
HF cetaceans................ 173 dB SELcum............... <2
Phocid pinnipeds............ 201 dB SELcum............... .........
----------------------------------------------------------------------------------------------------------------
Medium Penetration Sub-Bottom Profiler (Sparker)
----------------------------------------------------------------------------------------------------------------
GeoMarine Geo-Source 800tip.............. LF cetaceans................ 219 dBpeak, 183 dB SELcum... --, < 1
MF cetaceans................ 230 dBpeak, 185 dB SELcum... .........
HF cetaceans................ 202 dBpeak, 155 dB SELcum... <4, <1
Phocid pinnipeds............ 218 dBpeak, 185 dB SELcum... --, <1
----------------------------------------------------------------------------------------------------------------
Medium Penetration Sub-Bottom Profiler (Boomer)
----------------------------------------------------------------------------------------------------------------
Applied Acoustics S-Boom Triple Plate LF cetaceans................ 219 dBpeak, 183 dB SELcum... --, <1
Boomer (1000j).
MF cetaceans................ 230 dBpeak, 185 dB SELcum... .........
HF cetaceans................ 202 dBpeak, 155 dB SELcum... <3, --
Phocid pinnipeds............ 218 dBpeak, 185 dB SELcum... .........
----------------------------------------------------------------------------------------------------------------
In the absence of Crocker and Fratantonio (2016) data, as noted
above, NMFS determined that field verified SLs could be used to
delineate Level A harassment isopleths which can be used to represent
all of the HRG equipment within that specific category. While there is
some uncertainty given that the SLs associated with assorted HRG
equipment are variable within a given category, all of the predicted
distances based on the field-verified source level are small enough to
support a prediction that Level A harassment is unlikely to occur.
While it is possible that Level A harassment isopleths of non-verified
equipment would be larger than those shown in Table 7, it is unlikely
that such zones would be substantially greater in size such that take
by Level A harassment would be expected. Therefore, NMFS is not
proposing to authorize any take from Level A harassment.
The methodology described above was also applied to calculate Level
B harassment isopleths as shown in Table 8. Note that the spherical
spreading propagation model (20logR) was used to derive behavioral
harassment isopleths for equipment measured by Crocker and Fratantonio
(2016) data. However, the practical spreading model (15logR) was used
to conservatively assess distances to Level B harassment thresholds for
equipment not tested by Crocker and
[[Page 36074]]
Fratantonio (2016). Table 8 shows calculated Level B harassment
isopleths for specific equipment tested by Crocker and Fratantonio
(2016) which is applied to all devices within a given category. In
cases where Crocker and Fratantonio (2016) collected measurement on
more than one device, the largest calculated isopleth is used to
represent the entire category. Table 8 also shows field-verified SLs
and associated Level B harassment isopleths for equipment categories
that lack relevant Crocker & Fratantonio (2016) measurements.
Additionally, Table 8 also references the specific field verification
studies that were used to develop the isopleths. For these categories,
the largest calculated isopleth in each category was also used to
represent all equipment within that category.
Further information depicting how Level B harassment isopleths were
derived for each equipment category is described below:
USBL and GAPS: There are no relevant information sources or
measurement data within the Crocker and Fratantonio (2016) report.
However, SSV tests were conducted on the Sonardyne Ranger 2 (Gardline
2016a, 2017) and the IxSea GAPS System (MAI 2018b). Of the two devices,
the IxSea GAPS System had the larger Level B harassment isopleth
calculated at a distance of 6 m. It is assumed that all equipment
within this category will have the same Level B harassment isopleth.
Parametric SBP: There are no relevant data contained in Crocker and
Fratantonio (2016) report for parametric SBPs. However, results from an
SSV study showed a Level B harassment isopleth of 63 m for the Innomar-
2000 SES Medium 100 system (Subacoustech 2018). Therefore, 63 m will
serve as the Level B harassment isopleth for all parametric SBP
devices.
SBP (Chirp): Crocker and Fratantonio (2016) tested two chirpers,
the Edge Tech (ET) models 424 and 512. The largest calculated isopleth
is 7 m associated with the Edgetech 512. This distance will be applied
to all other HRD equipment within this category.
SBP (sparkers): The Applied Acoustics Dura-Spark 400 was the only
sparker tested by Crocker and Fratantonio (2016). The Level B
harassment isopleth calculated for this devise is 141 m and represents
all equipment within this category.
SBP (Boomers): The Crocker and Fratantonio report (2016) included
data on the Applied Acoustics S-Boom Triple Plate Boomer (1,000J) and
the Applied Acoustics S-Boom Boomer (700J). The results showed
respective Level B harassment isopleths of 141 m and 178 m. Therefore,
the Level B harassment isopleth for both boomers will be established at
a distance of 178 m.
Table 8--Distances to Level B Harassment Isopleths
------------------------------------------------------------------------
Measured SSV level
Lateral at closest point of
HRG survey equipment distance to approach single
Level B (m) pulse SPL (dB re
1[mu]Pa\2\)
------------------------------------------------------------------------
USBL & GAPS Transceiver
------------------------------------------------------------------------
Sonardyne Ranger 2 \a\............ 2 126 to 132 @40 m
Sonardyne Scout Pro............... .............. N/A
Easytrak Nexus 2 USBL............. .............. N/A
IxSea GAPS System \e\............. 6 144 @35 m
Kongsberg HiPAP 501/502 USBL...... .............. N/A
Edgetech BATS II.................. .............. N/A
------------------------------------------------------------------------
Shallow Sub-Bottom Profiler (Chirp)
------------------------------------------------------------------------
Edgetech 3200 \f\................. 5 153 @30 m
EdgeTech 216 \e\.................. 2 142 @35 m
EdgeTech 424...................... 6 Crocker and
Fratantonio (2016):
SL = 176
EdgeTech 512 \c\.................. 2.4 141 dB @40 m
130 dB @200 m
7 Crocker and
Fratantonio (2016):
SL = 177
Teledyne Benthos Chirp III--TTV .............. N/A
170.
GeoPulse 5430 A Sub-Bottom 4 145 @20 m
Profiler \a\.
PanGeo LF Chirp (Corer)........... .............. N/A
PanGeo HF Chirp (Corer)........... .............. N/A
------------------------------------------------------------------------
Parametric Sub-Bottom Profiler
------------------------------------------------------------------------
Innomar SES-2000 Medium 100 63 129 to 133 @100 m
Parametric Sub-Bottom Profiler
\b\.
Innomar SES-2000 Medium 70 .............. N/A
Parametric Sub-Bottom Profiler.
Innomar SES-2000 Standard & Plus .............. N/A
Parametric Sub-Bottom Profiler.
Innomar SES-2000 Quattro.......... .............. N/A
PanGeo 2i Parametric (Corer)...... .............. N/A
------------------------------------------------------------------------
Medium Penetration Sub-Bottom Profiler (Sparker)
------------------------------------------------------------------------
GeoMarine Geo-Source 400tip....... .............. N/A
GeoMarine Geo-Source 600tip \a\... 34 155@20 m
GeoMarine Geo-Source 800tip \a\... 86 144@200 m
Applied Acoustics Dura-Spark 400 141 Crocker and
System \g\. Fratantonio (2016);
SL = 203
GeoResources Sparker 800 System... .............. N/A
------------------------------------------------------------------------
Medium Penetration Sub-Bottom Profiler (Boomer)
------------------------------------------------------------------------
Applied Acoustics S-Boom Boomer 20 146 @144
1000 J operation d g. 141 Crocker and
Fratantonio (2016);
SL = 203
[[Page 36075]]
Applied Acoustics S-Boom Boomer/ 14 142 @38 m
700 J operation d g. 178 Crocker and
Fratantonio (2016);
SL = 205
------------------------------------------------------------------------
Sources:
\a\ Gardline 2016a, 2017.
\b\ Subacoustech 2018.
\c\ MAI 2018a.
\d\ NCE, 2018.
\e\ MAI 2018b.
\f\ Subacoustech 2017.
\g\ Crocker and Fratantonio, 2016.
For the purposes of estimated take and implementing proposed
mitigation measure, it is assumed that all HRG equipment will operate
concurrently. Therefore, NMFS conservatively utilized the largest
isopleth of 178 m, derived from the Applied Acoustics S-Boom Boomer
medium SBP, to establish the Level B harassment zone for all HRG
categories and devices.
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 by a single vessel in a single day of
the survey 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. The daily area is
multiplied by the marine mammal density of a given species. This value
is then multiplied by the number of proposed vessel days (666).
HRG survey equipment has the potential to cause harassment as
defined by the MMPA (160 dBRMS re 1 [micro]Pa). As noted
previously, all noise producing survey equipment/sources are assumed to
be operated concurrently by each survey vessel on every vessel day. The
greatest distance to the Level B harassment threshold of 160
dBRMS90% re 1 [mu]Pa level B for impulsive sources is 178 m
associated with the Applied Acoustics S-Boom Boomer (700J) (Crocker &
Fratantonio, 2016). Therefore, this distance is conservatively used to
estimate take by Level B harassment.
The estimated distance of the daily vessel trackline was determined
using the estimated average speed of the vessel and the 24-hour
operational period within each of the corresponding survey segments.
Estimates of incidental take by HRG survey equipment are calculated
using the 178 m Level B harassment isopleth, estimated daily vessel
track of approximately 70 km, and the daily ensonified area of 25.022
km\2\ for 24-hour operations as shown in Table 9, multiplied by 666
days.
Table 9--Survey Segment Distances and Level B Harassment Isopleth and Zone
----------------------------------------------------------------------------------------------------------------
Number of Estimated Level Calculated ZOI
Survey segment active survey distances per harassment per day
vessel days day (km) isopeth (m) (km\2\)
----------------------------------------------------------------------------------------------------------------
Lease Area OCS-A 0486........................... 79 70.000 178 25.022
Lease Area OCS-A 0487........................... 140 .............. .............. ..............
Lease Area OCS-A 0500........................... 94 .............. .............. ..............
ECR Corridor(s)................................. 353 .............. .............. ..............
----------------------------------------------------------------------------------------------------------------
The data used as the basis for estimating species density for the
Lease Area are derived from data provided by Duke Universities' Marine
Geospatial Ecology Lab and the Marine-life Data and Analysis Team. This
data set is a compilation of the best available marine mammal data
(1994-2018) and was prepared in a collaboration between Duke
University, Northeast Regional Planning Body, University of Carolina,
the Virginia Aquarium and Marine Science Center, and NOAA (Roberts et
al. 2016a; Curtice et al. 2018). Recently, these data have been updated
with new modeling results and have included density estimates for
pinnipeds (Roberts et al. 2016b; 2017; 2018). Because the seasonality
of, and habitat use by, gray seals roughly overlaps with harbor seals,
the same abundance estimate is applicable. Pinniped density data (as
presented in Roberts et al. 2016b; 2017; 2018) were used to estimate
pinniped densities for the Lease Area Survey segment and ECR Corridor
Survey segment(s). Density data from Roberts et al. (2016b; 2017; 2018)
were mapped within the boundary of the Survey Area for each segment
using geographic information systems. For all Survey Area locations,
the maximum densities as reported by Roberts et al. (2016b; 2017;
2018), were averaged over the survey duration (for spring, summer, fall
and winter) for the entire HRG survey area based on the proposed HRG
survey schedule as depicted in Table 7. The Level B ensonified area and
the projected duration of each respective survey segment was used to
produce the estimated take calculations provided in Table 10.
[[Page 36076]]
Table 10--Marine Mammal Density and Estimated Level B Harassment Take Numbers at 178 m Isopleth
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Lease area OCS-A 0500 Lease area OCS-A 0486 Lease area OCS-A 0487 ECR corridor(s) Adjusted totals
------------------------------------------------------------------------------------------------------------------------------------
Average Average Average Average
Species seasonal seasonal seasonal seasonal Take
density \a\ Calculated density \a\ Calculated density \a\ Calculated density \a\ Calculated authorization Percent of
(No./100 take (No.) (No./100 take (No.) (No./100 take (No.) (No./100 take (No.) (No.) population
km[sup2]) km[sup2]) km[sup2]) km[sup2])
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale................................. 0.502 11.798 0.383 7.570 0.379 13.262 0.759 67.029 \c\ 10 2.2
Humpback whale............................................. 0.290 6.814 0.271 5.354 0.277 9.717 0.402 35.537 58 6.4
Fin whale.................................................. 0.350 8.221 0.210 4.157 0.283 9.929 0.339 29.905 52 3.2
Sei whale.................................................. 0.014 0.327 0.005 0.106 0.009 0.306 0.011 0.946 2 0.5
Sperm whale................................................ 0.018 0.416 0.014 0.272 0.017 0.581 0.047 4.118 5 0.2
Minke whale................................................ 0.122 2.866 0.075 1.487 0.094 3.275 0.126 11.146 19 0.7
Long-finned pilot whale.................................... 1.895 44.571 0.504 9.969 1.012 35.449 1.637 144.590 235 4.2
Bottlenose dolphin......................................... 1.992 46.844 1.492 57.800 1.478 43.874 25.002 2,208.314 2,357 3.0
Short beaked common dolphin................................ 22.499 529.176 7.943 157.012 14.546 509.559 19.198 1,695.655 2,892 4.1
Atlantic white-sided dolphin............................... 7.349 172.857 2.006 39.656 3.366 117.896 7.634 674.282 1,005 2.1
Spotted dolphin............................................ 0.105 2.477 2.924 0.313 1.252 1.119 0.109 9.611 \d\ 50 0.1
Risso's dolphin............................................ 0.037 0.859 0.016 0.120 0.032 0.498 0.037 3.291 \d\ 30 0.2
Harbor porpoise............................................ 5.389 126.757 5.868 115.997 4.546 159.253 20.098 1,775.180 2,177 <0.1
Harbor seal \b\............................................ 7.633 179.522 6.757 133.558 3.966 138.918 45.934 4,057.192 4,509 5.9
Gray Seal \b\.............................................. 7.633 179.522 6.757 133.558 3.966 138.918 45.934 4,057.192 4,509 16.6
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
\a\ Cetacean density values from Duke University (Roberts et al. 2016, 2017, 2018).
\b\ Pinniped density values from Duke University (Roberts et al. 2016, 2017, 2018) reported as ``seals'' and not species-specific.
\c\ Exclusion zone exceeds Level B isopleth; take adjusted to 10 given duration of survey.
\d\ The number of authorized takes (Level B harassment only) for these species has been increased from the estimated take to mean group size. Source for Atlantic spotted dolphin group size
estimate is: Jefferson et al. (2008). Source for Risso's dolphin group size estimate is: Baird and Stacey (1991).
For the North Atlantic right whale, NMFS proposes to establish a
500-m exclusion zone which substantially exceeds the distance to the
level B harassment isopleth (178 m). However, Orsted will be operating
24 hours per day for a total of 666 vessel days. Even with the
implementation of mitigation measures (including night-vision goggles
and thermal clip-ons) it is reasonable to assume that night time
operations for an extended period could result in a limited number of
right whales being exposed to underwater sound at Level B harassment
levels. Given the fact that take has been conservatively calculated
based on the largest source, which will not be operating at all times,
and is thereby likely over-estimated to some degree, the fact that
Orsted will implement a shutdown zone at 2.5 times the predicted Level
B threshold distance for that largest source (and more than that for
the smaller sources), and the fact that night vision goggles with
thermal clips will be used for nighttime operations, NMFS predicts that
10 right whales may be taken by Level B harassment.
Proposed Mitigation
In order to issue an IHA under Section 101(a)(5)(D) of the MMPA,
NMFS must set forth the permissible methods of taking pursuant to such
activity, and other means of effecting the least practicable impact on
such species or stock and its habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance, and on
the availability of such 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 such
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) and 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.
With NMFS' input during the application process, Orsted is
requesting the following mitigation measures during site
characterization surveys utilizing HRG survey equipment. The mitigation
measures outlined in this section are based on protocols and procedures
that have been successfully implemented and previously approved by NMFS
(DONG Energy, 2016, ESS, 2013; Dominion, 2013 and 2014).
Orsted will develop an environmental training program that will be
provided to all vessel crew prior to the start of survey and during any
changes in crew such that all survey personnel are fully aware and
understand the mitigation, monitoring and reporting requirements. Prior
to implementation, the training program will be provided to NOAA
Fisheries for review and approval. Confirmation of the training and
understanding of the requirements will be documented on a training
course log sheet. Signing the log sheet will certify that the crew
members understand and will comply with the necessary requirements
throughout the survey event.
Marine Mammal Monitoring Zone, Harassment Zone and Exclusion Zone
Protected species observers (PSOs) will observe the following
monitoring and exclusion zones for the presence of marine mammals:
500-m exclusion zone for North Atlantic right whales;
100-m exclusion zone for large whales (except North
Atlantic right whales); and
180-m Level B harassment zone for all marine mammals
except for North Atlantic right whales. This represents the largest
Level B harassment isopleth applicable to all hearing groups.
If a marine mammal is detected approaching or entering the
exclusion zones during the HRG survey, the vessel
[[Page 36077]]
operator would adhere to the shutdown procedures described below to
minimize noise impacts on the animals.
At all times, the vessel operator will maintain a separation
distance of 500 m from any sighted North Atlantic right whale as
stipulated in the Vessel Strike Avoidance procedures described below.
These stated requirements will be included in the site-specific
training to be provided to the survey team.
Pre-Clearance of the Exclusion Zones
Orsted will implement a 30-minute clearance period of the exclusion
zones prior to the initiation of ramp-up. During this period the
exclusion zones will be monitored by the PSOs, using the appropriate
visual technology for a 30-minute period. Ramp up may not be initiated
if any marine mammal(s) is within its respective exclusion zone. If a
marine mammal is observed within an exclusion zone during the pre-
clearance period, ramp-up may not begin until the animal(s) has been
observed exiting its respective exclusion zone or until an additional
time period has elapsed with no further sighting (i.e., 15 minutes for
small odontocetes and 30 minutes for all other species).
Ramp-Up
A ramp-up procedure will be used for HRG survey equipment capable
of adjusting energy levels at the start or re-start of HRG survey
activities. A ramp-up procedure will be used at the beginning of HRG
survey activities in order to provide additional protection to marine
mammals near the Survey Area by allowing them to vacate the area prior
to the commencement of survey equipment use. The ramp-up procedure will
not be initiated during periods of inclement conditions or if the
exclusion zones cannot be adequately monitored by the PSOs, using the
appropriate visual technology for a 30-minute period.
A ramp-up would begin with the powering up of the smallest acoustic
HRG equipment at its lowest practical power output appropriate for the
survey. When technically feasible the power would then be gradually
turned up and other acoustic sources would be added.
Ramp-up activities will be delayed if a marine mammal(s) enters its
respective exclusion zone. Ramp-up will continue if the animal has been
observed exiting its respective exclusion zone or until an additional
time period has elapsed with no further sighting (i.e., 15 minutes for
small odontocetes and 30 minutes for all other species).
Shutdown Procedures
An immediate shut-down of the HRG survey equipment will be required
if a marine mammal is sighted at or within its respective exclusion
zone. The vessel operator must comply immediately with any call for
shut-down by the Lead PSO. Any disagreement between the Lead PSO and
vessel operator should be discussed only after shut-down has occurred.
Subsequent restart of the survey equipment can be initiated if the
animal has been observed exiting its respective exclusion zone with 30
minutes of the shut-down or until an additional time period has elapsed
with no further sighting (i.e., 15 minutes for small odontocetes and 30
minutes for all other species).
If a species for which authorization has not been granted, or, a
species for which authorization has been granted but the authorized
number of takes have been met, approaches or is observed within the 180
m Level B harassment zone, shutdown must occur.
If the acoustic source is shut down for reasons other than
mitigation (e.g., mechanical difficulty) for less than 30 minutes, it
may be activated again without ramp-up, if PSOs have maintained
constant observation and no detections of any marine mammal have
occurred within the respective exclusion zones. If the acoustic source
is shut down for a period longer than 30 minutes and PSOs have
maintained constant observation then ramp-up procedures will be
initiated as described in previous section.
The shutdown requirement is waived for small delphinids of the
following genera: Delphinus, Lagenodelphis, Lagenorhynchus,
Lissodelphis, Stenella, Steno, and Tursiops. If a delphinid (individual
belonging to the indicated genera of the Family Delphinidae), is
visually detected within the exclusion zone, no shutdown is required
unless the visual PSO confirms the individual to be of a genus other
than those listed, in which case a shutdown is required.
Vessel Strike Avoidance
Orsted will ensure that vessel operators and crew maintain a
vigilant watch for cetaceans and pinnipeds and slow down or stop their
vessels to avoid striking these species. Survey vessel crew members
responsible for navigation duties will receive site-specific training
on marine mammal and sea turtle sighting/reporting and vessel strike
avoidance measures. Vessel strike avoidance measures will include the
following, except under extraordinary circumstances when complying with
these requirements would put the safety of the vessel or crew at risk:
All vessel operators will comply with 10 knot (<18.5 km
per hour [km/h]) speed restrictions in any Dynamic Management Area
(DMA) when in effect and in Mid-Atlantic Seasonal Management Areas
(SMA) from November 1 through April 30;
All vessel operators will reduce vessel speed to 10 knots
or less when mother/calf pairs, pods, or larger assemblages of non-
delphinoid cetaceans are observed near an underway vessel;
All survey vessels will maintain a separation distance of
1,640 ft (500 m) 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/h) or less
until the 1,640-ft (500-m) minimum separation distance has been
established. If a North Atlantic right whale is sighted in a vessel's
path, or within 330 ft (100 m) 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 330 ft (100 m). If stationary, the
vessel must not engage engines until the North Atlantic right whale has
moved beyond 330 ft (100 m);
All vessels will maintain a separation distance of 330 ft
(100 m) or greater from any sighted non-delphinoid (i.e., mysticetes
and sperm whales) cetaceans. 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 330 ft (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 330 ft (100 m);
All vessels will maintain a separation distance of 164 ft
(50 m) or greater from any sighted delphinid cetacean. Any vessel
underway remain parallel to a sighted delphinid cetacean's course
whenever possible, and avoid excessive speed or abrupt changes in
direction. Any vessel underway reduces vessel speed to 10 knots or less
when pods (including mother/calf pairs) or large assemblages of
delphinid cetaceans are observed. Vessels may not adjust course and
speed until the delphinid cetaceans have moved beyond 164 ft (50 m)
and/or the abeam of the underway vessel;
All vessels underway will not divert to approach any
delphinid
[[Page 36078]]
cetacean or pinniped. Any vessel underway will avoid excessive speed or
abrupt changes in direction to avoid injury to the sighted delphinid
cetacean or pinniped; and
All vessels will maintain a separation distance of 164 ft
(50 m) or greater from any sighted pinniped.
Seasonal Operating Requirements
Between watch shifts members of the monitoring team will consult
NOAA Fisheries North Atlantic right whale reporting systems for the
presence of North Atlantic right whales throughout survey operations.
Survey vessels may transit the SMA located off the coast of Rhode
Island (Block Island Sound SMA) and at the entrance to New York Harbor
(New York Bight SMA). The seasonal mandatory speed restriction period
for this SMA is November 1 through April 30.
Throughout all survey operations, Orsted will monitor NOAA
Fisheries North Atlantic right whale reporting systems for the
establishment of a DMA. If NOAA Fisheries should establish a DMA in the
Lease Area under survey, the vessels will abide by speed restrictions
in the DMA per the lease condition.
Based on our evaluation of the applicant's proposed measures, as
well as other measures considered by NMFS, NMFS has preliminarily
determined that the proposed mitigation measures provide the means of
effecting the least practicable impact on marine mammals species or
stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance.
Proposed Monitoring and Reporting
In order to issue an IHA for an activity, Section 101(a)(5)(D) of
the MMPA states that NMFS must set forth, ``requirements pertaining to
the monitoring and reporting of such taking.'' The MMPA implementing
regulations at 50 CFR 216.104 (a)(13) indicate that requests for
authorizations must include the suggested means of accomplishing the
necessary monitoring and reporting that will result in increased
knowledge of the species and of the level of taking or impacts on
populations of marine mammals that are expected to be present in the
proposed action area. Effective reporting is critical both to
compliance as well as ensuring that the most value is obtained from the
required monitoring.
Monitoring and reporting requirements prescribed by NMFS should
contribute to improved understanding of one or more of the following:
Occurrence of marine mammal species or stocks in the area
in which take is anticipated (e.g., presence, abundance, distribution,
density);
Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) Action or environment
(e.g., source characterization, propagation, ambient noise); (2)
affected species (e.g., life history, dive patterns); (3) co-occurrence
of marine mammal species with the action; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors;
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks;
Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important physical components of
marine mammal habitat); and
Mitigation and monitoring effectiveness.
Proposed Monitoring Measures
Visual monitoring of the established monitoring and exclusion
zone(s) for the HRG surveys will be performed by qualified, NMFS-
approved PSOs, the resumes of whom will be provided to NMFS for review
and approval prior to the start of survey activities. During these
observations, the following guidelines shall be followed:
Other than brief alerts to bridge personnel of maritime hazards and
the collection of ancillary wildlife data, no additional duties may be
assigned to the PSO during his/her visual observation watch. For all
HRG survey segments, an observer team comprising a minimum of four NOAA
Fisheries-approved PSOs, operating in shifts, will be stationed aboard
respective survey vessels. Should the ASV be utilized, at least one PSO
will be stationed aboard the mother vessel to monitor the ASV
exclusively. PSOs will work in shifts such that no one monitor will
work more than 4 consecutive hours without a 2-hour break or longer
than 12 hours during any 24-hour period. Any time that an ASV is in
operation, PSOs will work in pairs. During daylight hours without ASV
operations, a single PSO will be required. PSOs will rotate in shifts
of 1 on and 3 off during daylight hours when an ASV is not operating
and work in pairs during all nighttime operations.
The PSOs will begin observation of the monitoring and exclusion
zones during all HRG survey operations. Observations of the zones will
continue throughout the survey activity and/or while equipment
operating below 200 kHz are in use. The PSOs will be responsible for
visually monitoring and identifying marine mammals approaching or
entering the established zones during survey activities. It will be the
responsibility of the Lead PSO on duty to communicate the presence of
marine mammals as well as to communicate and enforce the action(s) that
are necessary to ensure mitigation and monitoring requirements are
implemented as appropriate.
PSOs will be equipped with binoculars and will have the ability to
estimate distances to marine mammals located in proximity to their
respective exclusion zones and monitoring zone using range finders.
Reticulated binoculars will also be available to PSOs for use as
appropriate based on conditions and visibility to support the siting
and monitoring of marine species. Camera equipment capable of recording
sightings and verifing species identification will be utilized. During
night operations, night-vision equipment (night-vision goggles with
thermal clip-ons) and infrared technology will be used. Position data
will be recorded using hand-held or vessel global positioning system
(GPS) units for each sighting.
Observations will take place from the highest available vantage
point on all the survey vessels. General 360-degree scanning will occur
during the monitoring periods, and target scanning by the PSOs will
occur when alerted of a marine mammal presence.
For monitoring around the ASV, a dual thermal/HD camera will be
installed on the mother vessel, facing forward, angled in a direction
so as to provide a field of view ahead of the vessel and around the
ASV. One PSO will be assigned to monitor the ASV exclusively at all
times during both day and night when in use. The ASV will be kept in
sight of the mother vessel at all times (within 800 m). This dedicated
PSO will have a clear, unobstructed view of the ASV's exclusion and
monitoring zones. While conducting survey operations, PSOs will adjust
their positions appropriately to ensure adequate coverage of the entire
exclusion and monitoring zones around the respective sound sources.
PSOs will also be able to monitor the real time output of the camera on
hand-held iPads. Images from the cameras can be
[[Page 36079]]
captured for review and to assist in verifying species identification.
A monitor will also be installed on the bridge displaying the real-time
picture from the thermal/HD camera installed on the front of the ASV
itself, providing a further forward field of view of the craft. In
addition, night-vision goggles with thermal clip-ons, as mentioned
above, and a hand-held spotlight will be provided such that PSOs can
focus observations in any direction, around the mother vessel and/or
the ASV. The ASV camera is only utilized at night as part of the
reduced visibility program, during which one PSO monitors the ASV
camera and the forward-facing camera mounted on mothership. The second
PSO would use the hand held devices to cover the areas around the
mothership that the forward-facing camera could not cover.
Observers will maintain 360[deg] coverage surrounding the
mothership vessel and the ASV when in operation, which will travel
ahead and slightly offset to the mothership on the survey line. PSOs
will adjust their positions appropriately to ensure adequate coverage
of the entire exclusion zone around the mothership and the ASV.
As part of the monitoring program, PSOs will record all sightings
beyond the established monitoring and exclusion zones, as far as they
can see. Data on all PSO observations will be recorded based on
standard PSO collection requirements.
Proposed Reporting Measures
Orsted will provide the following reports as necessary during
survey activities:
Notification of Injured or Dead Marine Mammals
In the unanticipated event that the specified HRG and geotechnical
activities lead to an unauthorized injury of a marine mammal (Level A
harassment) or mortality (e.g., ship-strike, gear interaction, and/or
entanglement), Orsted would immediately cease the specified activities
and report the incident to the Chief of the Permits and Conservation
Division, Office of Protected Resources and the NOAA Greater Atlantic
Regional Fisheries Office (GARFO) Stranding Coordinator. The report
would 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 would not resume until NMFS is able to review the
circumstances of the event. NMFS would work with Orsted to minimize
reoccurrence of such an event in the future. Orsted would not resume
activities until notified by NMFS.
In the event that Orsted discovers an injured or dead marine mammal
and determines that the cause of the injury or death is unknown and the
death is relatively recent (i.e., in less than a moderate state of
decomposition), Orsted would immediately report the incident to the
Chief of the Permits and Conservation Division, Office of Protected
Resources and the GARFO Stranding Coordinator. The report would include
the same information identified in the paragraph above. Activities
would be allowed to continue while NMFS reviews the circumstances of
the incident. NMFS would work with the Applicant to determine if
modifications in the activities are appropriate.
In the event that Orsted discovers an injured or dead marine mammal
and determines that the injury or death is not associated with or
related to the activities authorized in the IHA (e.g., previously
wounded animal, carcass with moderate to advanced decomposition, or
scavenger damage), Orsted would report the incident to the Chief of the
Permits and Conservation Division, Office of Protected Resources, NMFS,
and the GARFO Stranding Coordinator, within 24 hours of the discovery.
Orsted would provide photographs or video footage (if available) or
other documentation of the stranded animal sighting to NMFS. Orsted can
continue its operations in such a case.
Within 90 days after completion of the marine site characterization
survey activities, a draft technical report will be provided to NMFS
that fully documents the methods and monitoring protocols, summarizes
the data recorded during monitoring, estimates the number of marine
mammals that may have been taken during survey activities, and provides
an interpretation of the results and effectiveness of all monitoring
tasks. Any recommendations made by NMFS must be addressed in the final
report prior to acceptance by NMFS.
Negligible Impact Analysis and Determination
NMFS has defined negligible impact as an impact resulting from the
specified activity that cannot be reasonably expected to, and is not
reasonably likely to, adversely affect the species or stock through
effects on annual rates of recruitment or survival (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough
information on which to base an impact determination. In addition to
considering estimates of the number of marine mammals that might be
``taken'' through harassment, NMFS considers other factors, such as the
likely nature of any responses (e.g., intensity, duration), the context
of any responses (e.g., critical reproductive time or location,
migration), as well as effects on habitat, and the likely effectiveness
of the mitigation. 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, this introductory discussion of our analyses
applies to all the species listed in Table 8, given that many of the
anticipated effects of this project on different marine mammal stocks
are expected to be relatively similar in nature. Where there are
meaningful differences between species or stocks, or groups of species,
in anticipated individual responses to activities, impact of expected
take on the population due to differences in population status, or
impacts on habitat, they are described independently in the analysis
below.
As discussed in the ``Potential Effects of the Specified Activity
on Marine Mammals and Their Habitat'' section, PTS, TTS, masking, non-
auditory physical effects, and vessel strike are not expected to occur.
Marine mammal habitat may experience limited physical
[[Page 36080]]
impacts in the form of grab samples taken from the sea floor. This
highly localized habitat impact is negligible in relation to the
comparatively vast area of surrounding open ocean, and would not be
expected to result in any effects to prey availability. 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. Marine mammal feeding
behavior is not likely to be significantly impacted. Prey species are
mobile, and are broadly distributed throughout the Survey Area;
therefore, marine mammals that may be temporarily displaced during
survey activities are expected to be able to resume foraging once they
have moved away from areas with disturbing levels of underwater noise.
Because of the 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.
ESA-Listed Marine Mammal Species
ESA-listed species for which takes are proposed are right, fin,
sei, and sperm whales, and these effects are anticipated to be limited
to lower level behavioral effects. NMFS does not anticipate that
serious injury or mortality would occur to ESA-listed species, even in
the absence of proposed mitigation and the proposed authorization does
not authorize any serious injury or mortality. As discussed in the
Potential Effects section, non-auditory physical effects and vessel
strike are not expected to occur. We expect that most 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). The proposed survey is not anticipated to affect the
fitness or reproductive success of individual animals. Since impacts to
individual survivorship and fecundity are unlikely, the proposed 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.
There is no designated critical habitat for any ESA-listed marine
mammals within the Survey Area.
Biologically Important Areas (BIA)
The proposed Survey Area includes a fin whale feeding BIA effective
between March and October. The fin whale feeding area is sufficiently
large (2,933 km\2\), and the acoustic footprint of the proposed survey
is sufficiently small (<20 km\2\ ensonified per day to the Level B
harassment threshold assuming simultaneous operation of two survey
ships) that whale feeding habitat would not be reduced appreciably. Any
fin whales temporarily displaced from the proposed survey 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 fin whales from the BIA would be expected to be temporary in nature.
Therefore, we do not expect fin whale feeding to be negatively impacted
by the proposed survey.
The proposed survey area includes a biologically important
migratory area for North Atlantic right whales (effective March-April
and November-December) that extends from Massachusetts to Florida
(LaBrecque, et al., 2015). Off the south coast of Massachusetts and
Rhode Island, this biologically important migratory area extends from
the coast to beyond the shelf break. The fact that the spatial acoustic
footprint of the proposed 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 proposed survey.
Required vessel strike avoidance measures will also decrease risk of
ship strike during migration. Additionally, only very limited take by
Level B harassment of North Atlantic right whales has been proposed as
HRG survey operations are required to shut down at 500 m to minimize
the potential for behavioral harassment of this species.
Unusual Mortality Events (UME)
A UME is defined under the MMPA as ``a stranding that is
unexpected; involves a significant die-off of any marine mammal
population; and demands immediate response.'' Four UMEs are ongoing and
under investigation relevant to HRG survey area. These involve humpback
whales, North Atlantic right whales, minke whales, and pinnipeds.
Specific information for each ongoing UME is provided below. There is
currently no direct connection between the four UMEs, as there is no
evident cause of stranding or death that is common across the species
involved in the different UMEs. Additionally, strandings across these
species are not clustering in space or time.
As noted previously, elevated humpback whale mortalities have
occurred along the Atlantic coast from Maine through Florida since
January 2016 Of the cases examined, approximately half had evidence of
human interaction (ship strike or entanglement). 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. Preliminary findings in several of
the whales have shown evidence of human interactions or infectious
disease. 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.
Direct physical interactions (ship strikes and entanglements)
appear to be responsible for many of the UME humpback and right whale
mortalities recorded. The proposed 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 proposed 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.
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.
Accordingly, Orsted did not request, and NMFS is not proposing to
authorize, take of marine mammals by
[[Page 36081]]
serious injury, or mortality. NMFS expects that most takes would
primarily 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 are considered to be of low severity and with no lasting
biological consequences (e.g., Southall et al., 2007). Since the source
is mobile, a specified 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
harassment.
In summary and as described above, the following factors primarily
support our preliminary determination that the impacts resulting from
this activity are not expected to adversely affect the species or stock
through effects on annual rates of recruitment or survival:
No mortality or serious injury is anticipated or
authorized;
No Level A harassment (PTS) is anticipated;
Foraging success is not likely to be significantly
impacted as effects on species that serve as prey species for marine
mammals from the survey are expected to be minimal;
The availability of alternate areas of similar habitat
value for marine mammals to temporarily vacate the survey area during
the planned survey to avoid exposure to sounds from the activity;
Take is anticipated to be primarily Level B behavioral
harassment consisting of brief startling reactions and/or temporary
avoidance of the Survey Area;
While the Survey Area is within areas noted as
biologically important for north Atlantic right whale migration, the
activities would occur in such a comparatively small area such that any
avoidance of the survey 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 any
take of the species. Similarly, due to the small footprint of the
survey activities in relation to the size of a biologically important
area for fin whales foraging, the survey activities would not affect
foraging behavior of this species; and
The proposed mitigation measures, including visual
monitoring and shutdowns, are expected to minimize potential impacts to
marine mammals.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the proposed monitoring and
mitigation measures, NMFS preliminarily finds that the total marine
mammal take from Orsted's proposed HRG survey activities will have a
negligible impact on the affected marine mammal species or stocks.
Small Numbers
As noted above, only small numbers of incidental take may be
authorized under Section 101(a)(5)(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 propose for authorization to
be taken, for all species and stocks, would be considered small
relative to the relevant stocks or populations (less than 17 percent
for all authorized species).
Based on the analysis contained herein of the proposed activity
(including the proposed mitigation and monitoring measures) and the
anticipated take of marine mammals, NMFS preliminarily finds that small
numbers of marine mammals will be taken relative to the population size
of the affected species or stocks.
Impact on Availability of Affected Species for Taking for Subsistence
Uses
There are no relevant subsistence uses of marine mammals implicated
by this action. Therefore, NMFS has determined that the total taking of
affected species or stocks would not have an unmitigable adverse impact
on the availability of such species or stocks for taking for
subsistence purposes.
Endangered Species Act
Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16
U.S.C. 1531 et seq.) requires that each Federal agency insure that any
action it authorizes, funds, or carries out is not likely to jeopardize
the continued existence of any endangered or threatened species or
result in the destruction or adverse modification of designated
critical habitat. To ensure ESA compliance for the issuance of IHAs,
NMFS consults internally, in this case with the Greater Atlantic
Regional Field Office (GARFO), whenever we propose to authorize take
for endangered or threatened species.
Within the project area, fin, Sei, humpback, North Atlantic right,
and sperm whale are listed as endangered under the ESA. Under section 7
of the ESA, BOEM consulted with NMFS on commercial wind lease issuance
and site assessment activities on the Atlantic Outer Continental Shelf
in Massachusetts, Rhode Island, New York and New Jersey Wind Energy
Areas. NOAA's GARFO issued a Biological Opinion concluding that these
activities may adversely affect but are not likely to jeopardize the
continued existence of fin whale or North Atlantic right whale. NMFS is
also consulting internally on the issuance of an IHA under section
101(a)(5)(D) of the MMPA for this activity and the existing Biological
Opinion may be amended to include an incidental take exemption for
these marine mammal species, as appropriate.
Proposed Authorization
As a result of these preliminary determinations, NMFS proposes to
issue an IHA to Orsted for HRG survey activities effective one year
from the date of issuance, provided the previously mentioned
mitigation, monitoring, and reporting requirements are incorporated. A
draft of the IHA itself is available for review in conjunction with
this notice at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-other-energy-activities-renewable.
Request for Public Comments
We request comment on our analyses, the proposed authorization, and
any other aspect of this Notice of Proposed IHA for the proposed
survey. We also request at this time comment on the potential renewal
of this proposed IHA as described in the paragraph below. Please
include with your comments any supporting data or literature citations
to help inform decisions on the request for this IHA or a subsequent
Renewal.
On a case-by-case basis, NMFS may issue a one-year IHA renewal with
an additional 15 days for public comments when (1) another year of
identical or nearly identical activities as described in the Specified
Activities section of this notice is planned or (2) the activities as
described in the Specified Activities section of this notice would not
be completed by the time the IHA expires and a second IHA would allow
for completion of the activities beyond that described in the Dates and
Duration section of this notice, provided all of the following
conditions are met:
[[Page 36082]]
A request for renewal is received no later than 60 days
prior to expiration of the current IHA.
The request for renewal must include the following:
(1) An explanation that the activities to be conducted under the
requested Renewal are identical to the activities analyzed under the
initial IHA, are a subset of the activities, or include changes so
minor (e.g., reduction in pile size) that the changes do not affect the
previous analyses, mitigation and monitoring requirements, or take
estimates (with the exception of reducing the type or amount of take
because only a subset of the initially analyzed activities remain to be
completed under the Renewal).
(2) A preliminary monitoring report showing the results of the
required monitoring to date and an explanation showing that the
monitoring results do not indicate impacts of a scale or nature not
previously analyzed or authorized.
Upon review of the request for Renewal, the status of the
affected species or stocks, and any other pertinent information, NMFS
determines that there are no more than minor changes in the activities,
the mitigation and monitoring measures will remain the same and
appropriate, and the findings in the initial IHA remain valid.
Dated: July 19, 2019.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2019-15802 Filed 7-25-19; 8:45 am]
BILLING CODE 3510-22-P