Notice2023-28336
Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Trident Seafoods Bunkhouse Dock Replacement Project, Kodiak, Alaska
Primary source
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Published
December 26, 2023
Issuing agencies
Commerce DepartmentNational Oceanic and Atmospheric Administration
Abstract
NMFS has received a request from Trident Seafoods Corporation (Trident) for authorization to take marine mammals incidental to pile driving and removal activities associated with the Bunkhouse Dock replacement project in Kodiak, Alaska. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to issue an incidental harassment authorization (IHA) to incidentally take marine mammals during the specified activities. NMFS is also requesting comments on a possible one-time, 1-year renewal that could be issued under certain circumstances and if all requirements are met, as described in Request for Public Comments at the end of this notice. NMFS will consider public comments prior to making any final decision on the issuance of the requested MMPA authorization and agency responses will be summarized in the final notice of our decision.
Full Text
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<title>Federal Register, Volume 88 Issue 246 (Tuesday, December 26, 2023)</title>
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[Federal Register Volume 88, Number 246 (Tuesday, December 26, 2023)]
[Notices]
[Pages 88874-88892]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2023-28336]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[RTID 0648-XD515]
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to Trident Seafoods Bunkhouse Dock
Replacement Project, Kodiak, Alaska
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; proposed incidental harassment authorization; request
for comments on proposed authorization and possible renewal.
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SUMMARY: NMFS has received a request from Trident Seafoods Corporation
(Trident) for authorization to take marine mammals incidental to pile
driving and removal activities associated with the Bunkhouse Dock
replacement project in Kodiak, Alaska. Pursuant to the Marine Mammal
Protection Act (MMPA), NMFS is requesting comments on its proposal to
issue an incidental harassment authorization (IHA) to incidentally take
marine mammals during the specified activities. NMFS is also requesting
comments on a possible one-time, 1-year renewal that could be issued
under certain circumstances and if all requirements are met, as
described in Request for Public Comments at the end of this notice.
NMFS will consider public comments prior to making any final decision
on the issuance of the requested MMPA authorization and agency
responses will be summarized in the final notice of our decision.
DATES: Comments and information must be received no later than January
25, 2024.
ADDRESSES: Comments should be addressed to Jolie Harrison, Chief,
Permits and Conservation Division, Office of Protected Resources,
National Marine Fisheries Service and should be submitted via email to
<a href="/cdn-cgi/l/email-protection#5d14090d732a3c3e35293833393233361d33323c3c733a322b"><span class="__cf_email__" data-cfemail="5e170a0e70293f3d362a3b303a3130351e30313f3f70393128">[email protected]</span></a>. 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: <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities">https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities</a>. In case of problems accessing these documents,
please call the contact listed above.
Instructions: NMFS is not responsible for comments sent by any
other method, to any other address or individual, or received after the
end of the comment period. Comments, including all attachments, must
not exceed a 25-megabyte file size. All comments received are a part of
the public record and will generally be posted online at <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities">https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities</a>. 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: Rachel Wachtendonk, Office of
Protected Resources, NMFS, (301) 427-8401.
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 proposed or, if the taking is limited to harassment, a notice of a
proposed IHA is provided to the public for review.
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other ``means of effecting the least practicable adverse
impact'' on the affected species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of the species or stocks for
taking for certain subsistence uses (referred to in shorthand as
``mitigation''); and requirements pertaining to the mitigation,
monitoring and reporting of the takings are set forth. The definitions
of all applicable MMPA statutory terms cited above are included in the
relevant sections below.
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must review our proposed action (i.e., the issuance of an IHA)
with respect to potential impacts on the human environment.
This action is consistent with categories of activities identified
in Categorical Exclusion B4 (IHAs with no anticipated serious injury or
mortality) of the Companion Manual for NAO 216-6A, which do not
individually or cumulatively have the potential for significant impacts
on the quality of the human environment and for which we have not
identified any extraordinary circumstances that would preclude this
categorical exclusion. Accordingly, NMFS has preliminarily determined
that the issuance of the proposed IHA qualifies to be categorically
excluded from further NEPA review.
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 June 15, 2023, NMFS received a request from Trident for an IHA
to take marine mammals incidental to vibratory
[[Page 88875]]
and impact pile driving to replace the Bunkhouse Dock at their facility
in Kodiak, Alaska. Following NMFS' review of the application, Trident
submitted a revised version on September 1, 2023. The application was
deemed adequate and complete on October 26, 2023. Trident's request is
for take of six species of marine mammals by Level B harassment only.
Neither Trident nor NMFS expect serious injury or mortality to result
from this activity and, therefore, an IHA is appropriate.
Description of Proposed Activity
Overview
Trident proposes to remove and replace the Bunkhouse Dock on the
shore of Near Island Channel in Kodiak, Alaska. The purpose of this
project is to remove the degraded dock and replace it with a new
structure to provide safe housing and waterfront infrastructure for
seafood processing. The activity includes the removal of existing piles
and the installation of both temporary and permanent piles of various
sizes. Takes of marine mammals by Level B harassment would occur due to
down-the-hole (DTH) drilling and vibratory pile driving and removal.
This project would occur Kodiak, Alaska along the western shore of Near
Island Channel within Township 27S. Construction activities are
expected to occur over 8 weeks starting in March 2024.
Dates and Duration
The proposed activities are expected to start in March 2024 and
last 8 weeks. It is expected to take 94 hours over 55 non-consecutive
days. All pile driving and removal would be completed during daylight
hours.
Specific Geographic Region
The proposed activities would take place at the Trident Seafoods
facility along the City of Kodiak's downtown working waterfront. It is
located on the western shore of Near Island Channel in Kodiak, Alaska
within Township 27S. All construction would occur within the footprint
of the existing Trident-owned Bunkhouse Dock. The timing of this work
is planned to not interfere with the commercial fishing season.
[GRAPHIC] [TIFF OMITTED] TN26DE23.000
Detailed Description of the Specified Activity
The Bunkhouse Dock replacement will include the removal of 100 14-
inch (in) (36 centimeter (cm)) diameter timber piles, 75 14-in (36-cm)
steel H-piles, and 60 16-in (41 cm) diameter steel pipe piles. Once the
existing piles are removed, 26 16-in (41 cm) diameter steel pipe piles
and 52 24-in (61 cm) diameter steel pipe piles would be installed to
support the new pier. The installation and removal of 52 temporary 24-
in (61 cm) diameter steel pipe piles would be completed to support
permanent pile installation. All piles will be removed with the
deadpull method with the vibratory hammer being used if the deadpull
method is unsuccessful. Temporary and permanent piles will be initially
installed with the vibratory hammer followed by the DTH drill to embed
them to their final depth. The work would be completed within the
footprint of the existing Bunkhouse Dock in Kodiak, Alaska.
[[Page 88876]]
Table 1--Number and Type of Piles To Be Installed and Removed
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Permanent pipe Permanent pipe
Existing pipe Existing H- Existing pile Temporary pile Temporary pile pile pile
pile removal pile removal removal installation removal installation installation
(steel) (steel) (timber) (steel) (steel) (steel) (steel)
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Pile Diameter size (in)................. 16 14 14 24 24 16 24
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Vibratory Pile Driving/Removal
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Total Quantity.......................... 60 75 100 20 20 26 52
Max # of Piles per day.................. 20 20 25 6 8 5 4
Vibratory time per pile (min)........... 2 2 2 2 2 2 2
Number of Days.......................... 3 4 4 3 3 5 13
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Down the Hole Drilling
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Total Quantity.......................... n/a n/a n/a 20 n/a 26 52
Piles per day........................... n/a n/a n/a 6 n/a 6 4
Duration time per pile (min)............ n/a n/a n/a 30 n/a 45 60
Number of Days.......................... n/a n/a n/a 3 n/a 4 13
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Proposed mitigation, monitoring, and reporting measures are
described in detail later in this document (please see Proposed
Mitigation and Proposed Monitoring and Reporting).
Description of Marine Mammals in the Area of Specified Activities
Sections 3 and 4 of the application summarize available information
regarding status and trends, distribution and habitat preferences, and
behavior and life history of the potentially affected species. NMFS
fully considered all of this information, and we refer the reader to
these descriptions, instead of reprinting the information. Additional
information regarding population trends and threats may be found in
NMFS' Stock Assessment Reports (SARs; <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments</a>) and
more general information about these species (e.g., physical and
behavioral descriptions) may be found on NMFS' website (<a href="https://www.fisheries.noaa.gov/find-species">https://www.fisheries.noaa.gov/find-species</a>).
Table 2 lists all species or stocks for which take is expected and
proposed to be authorized for this activity and summarizes information
related to the population or stock, including regulatory status under
the MMPA and Endangered Species Act (ESA) and potential biological
removal (PBR), where known. 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 serious injury or mortality is anticipated or proposed
to be authorized here, PBR and annual serious injury and mortality from
anthropogenic sources are included here as gross indicators of the
status of the species or stocks and other threats.
Marine mammal abundance estimates presented in this document
represent the total number of individuals that make up a given stock or
the total number estimated within a particular study or survey area.
NMFS' stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprises that stock. For some species, this geographic area may extend
beyond U.S. waters. All managed stocks in this region are assessed in
NMFS' U.S. 2022 SARs. All values presented in table 2 are the most
recent available at the time of publication and are available online
at: <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments</a>.
Table 2--Marine Mammal Species \4\ Likely To Occur Near the Project Area That May Be Taken by Trident's Activities
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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 Artiodactyla--Cetacea--Mysticeti (baleen whales)
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Family Balaenopteridae (rorquals):
Humpback Whale.................. Megaptera novaeangliae. Hawai[revaps]i \5\..... -, -, N 11,278 (0.56, 7,265, 127 27.09
2020).
Mexico-North Pacific T, D, Y N/A (N/A, N/A, 2006).. UND 0.57
\6\.
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Odontoceti (toothed whales, dolphins, and porpoises)
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Family Delphinidae:
Killer Whale.................... Orcinus orca........... Eastern North Pacific -, -, N 1,920 (N/A, 1,920, 19 1.3
Alaska Resident \7\. 2019).
Eastern North Pacific -, -, N 587 (N/A, 587, 2012).. 5.9 0.8
Gulf of Alaska,
Aleutian Islands and
Bering Sea Transient
\7\.
Family Phocoenidae (porpoises):
Dall's Porpoise................. Phocoenoides dalli..... AK \8\................. -, -, N UND (UND, UND, 2015).. UND 37
Harbor Porpoise................. Phocoena phocoena...... Gulf of Alaska......... -, -, Y 31,046 (0.21, N/A, UND 72
1998).
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[[Page 88877]]
Order Carnivora--Pinnipedia
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Family Otariidae (eared seals and
sea lions):
Steller Sea Lion................ Eumetopias jubatus..... Western \9\............ E, D, Y 52,932 (N/A, 52,932, 318 254
2019).
Family Phocidae (earless seals):
Harbor Seal..................... Phoca vitulina......... South Kodiak........... -, -, N 26,448 (N/A, 22,351, 939 127
2017).
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\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: <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region</a>. 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. A CV
associated with estimated mortality due to commercial fisheries is presented in some cases.
\4\ Information on the classification of marine mammal species can be found on the web page for The Society for Marine Mammalogy's Committee on Taxonomy
(<a href="https://marinemammalscience.org/science-and-publications/list-marine-mammal-species-subspecies/">https://marinemammalscience.org/science-and-publications/list-marine-mammal-species-subspecies/</a>; Committee on Taxonomy (2022)).
\5\ New SAR in 2022 following North Pacific humpback whale stock structure changes.
\6\ Abundance estimates are based upon data collected more than 8 years ago and, therefore, current estimates are considered unknown.
\7\ Nest is based upon counts of individuals identified from photo-ID catalogs.
\8\ The best available abundance estimate is likely an underestimate for the entire stock because it is based upon a survey that covered only a small
portion of the stock's range. \9\Nest is best estimate of counts, which have not been corrected for animals at sea during abundance surveys.
\9\ Nest is best estimate of counts, which have not been corrected for animals at sea during abundance surveys.
As indicated above, all six species (with eight managed stocks) in
table 2 temporally and spatially co-occur with the activity to the
degree that take is reasonably likely to occur. All species that could
potentially occur in the proposed project area are included in table 5
of the IHA application. While gray whales, North Pacific right whales,
minke whales, fin whales, Cuvier's beaked whales, sperm whales, Pacific
white-sided dolphins, and northern fur seals in the area, the temporal
and/or spatial occurrence of these species is such that take is not
expected to occur, and they are not discussed further beyond the
explanation provided here. These species are all considered to be rare
(no sightings in recent years) within the project area. Take of these
species has not been requested nor is proposed to be authorized and
these species are not considered further in this document.
Additional information relevant to our analyses (beyond that
included above, in the application, and on NMFS website) is included
below, as appropriate.
Humpback Whale
On September 8, 2016, NMFS divided the once single species into 14
distinct population segments (DPS) under the ESA, removed the species-
level listing as endangered, and, in its place, listed 4 DPSs as
endangered and one DPS as threatened (81 FR 62259, September 8, 2016).
The remaining nine DPSs were not listed. There are four DPSs in the
North Pacific, including Mexico, which is listed as threatened, and
Hawaii, which is not listed.
The 2022 Alaska and Pacific SARs described a revised stock
structure for humpback whales which modifies the previous stocks
designated under the MMPA to align more closely with the ESA-designated
DPSs (Caretta et al., 2023; Young et al., 2023). Specifically, the
three previous North Pacific humpback whale stocks (Central and western
North Pacific stocks and a CA/OR/WA stock) were replaced by five
stocks, largely corresponding with the ESA-designated DPSs. These
include Western North Pacific and Hawaii stocks and a Central America/
Southern Mexico-CA/OR/WA stock (which corresponds with the Central
America DPS). The remaining two stocks, corresponding with the Mexico
DPS, are the Mainland Mexico-CA/OR/WA and Mexico-North Pacific stocks
(Caretta et al., 2023; Young et al., 2023). The former stock is
expected to occur along the west coast from California to southern
British Columbia, while the latter stock may occur across the Pacific,
from northern British Columbia through the Gulf of Alaska and Aleutian
Islands/Bering Sea region to Russia.
The Hawai[revaps]i stock consists of one demographically
independent population (DIP)--Hawai[revaps]i-southeast Alaska/northern
British Columbia DIP and one unit--Hawai[revaps]i-north Pacific unit,
which may or may not be composed of multiple DIPs (Wade et al., 2021).
The DIP and unit are managed as a single stock at this time, due to the
lack of data available to separately assess them and lack of compelling
conservation benefit to managing them separately (NMFS, 2023; NMFS,
2019; NMFS, 2022b). The DIP is delineated based on two strong lines of
evidence: genetics and movement data (Wade et al., 2021). Whales in the
Hawai[revaps]i-southeast Alaska/northern British Columbia DIP winter
off Hawai[revaps]i and largely summer in southeast Alaska and northern
British Columbia (Wade et al., 2021). The group of whales that migrate
from Russia, western Alaska (Bering Sea and Aleutian Islands), and
central Alaska (Gulf of Alaska excluding southeast Alaska) to
Hawai[revaps]i have been delineated as the Hawai[revaps]i-North Pacific
unit (Wade et al., 2021). There are a small number of whales that
migrate between Hawa[revaps]i and southern British Columbia/Washington,
but current data and analyses do not provide a clear understanding of
which unit these whales belong to (Wade et al., 2021; Caretta et al.,
2023; Young et al., 2023).
The Mexico-North Pacific unit is likely composed of multiple DIPs,
based on movement data (Martien et al., 2021; Wade, 2021, Wade et al.,
2021). However, because currently available data and analyses are not
sufficient to delineate or assess DIPs within the unit, it was
designated as a single stock (NMFS, 2023a; NMFS, 2019; NMFS, 2022c).
Whales in this stock winter off Mexico and the Revillagigedo
Archipelago and summer primarily in Alaska waters (Martien et al.,
2021; Carretta et al., 2023; Young et al., 2023).
[[Page 88878]]
Wild et al. (2023) identified the waters around and to the East of
Kodiak Island (including the proposed project area) as a Biologically
Important Area (BIA) for humpback whales for feeding during the months
of May through September, with an importance score of 1 (the lowest of
three possible scores (1, 2, or 3), reflecting an Intensity score of 2
(indicating an area of moderate comparative significance) and a Data
Support score of 1 (lower relative confidence in the available
supporting data). While the majority of sightings occur outside of the
Near Island Channel, a singular humpback whale was documented
transiting the channel during the Kodiak Ferry Terminal construction in
March 2016 (NMFS 2017).
Steller Sea Lion
Steller sea lions were listed as threatened range-wide under the
ESA on November 26, 1990 (55 FR 49204). Steller sea lions were
subsequently partitioned into the western and eastern Distinct
Population Segments (DPSs; western and eastern stocks) in 1997 (62 FR
24345, May 5, 1997). The eastern DPS remained classified as threatened
until it was delisted in November 2013. The western DPS (those
individuals west of the 144[deg] W longitude or Cape Suckling, Alaska)
was upgraded to endangered status following separation of the DPSs, and
it remains endangered today. There is regular movement of both DPSs
across this 144[deg] W longitude boundary (Jemison et al., 2013)
however, due to the distance from this DPS boundary, it is likely that
only western DPS Steller sea lions are present in the project area.
Therefore, animals potentially affected by the project are assumed to
be part of the western DPS. Sea lions from the eastern DPS, are not
likely to be affected by the proposed activity and are not discussed
further.
Steller sea lions do not follow traditional migration patterns, but
will move from offshore rookeries in the summer to more protected
haulouts closer to shore in the winter. They use rookeries and haulouts
as resting spots as they follow prey movements and take foraging trips
for days, usually within a few miles of their rookery or haulout. They
are generalist marine predators and opportunistic feeders based on
seasonal abundance and location of prey. Steller sea lions forage in
nearshore as well as offshore areas, following prey resources. They are
highly social and are often observed in large groups while hauled out
but alone or in small groups when at sea (NMFS 2022).
Steller sea lions are frequent in the proposed project area as many
have become habituated to the human activity at the seafood processing
facilities. Steller sea lions regularly haul out on the Dog Bay float
in St. Herman Harbor, which is approximately 792 m (2,600 ft) from the
proposed project area. A bi-weekly census of Steller sea lions at the
Dog Bay float conducted from November 2015 to June 2016, in association
with the Kodiak Ferry Terminal project, revealed maximum numbers (>100)
from mid-March through mid-June, with 5,111 total observations from
November 2015 to June 2016 (NMFS 2019a). The highest average hourly
number (11-15/hour) of sea lions within the entire Kodiak Ferry
Terminal observation area occurred from February through April 2016
(NMFS 2019a).
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. 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, 2019) recommended that marine mammals be divided into hearing
groups based on directly measured (behavioral or auditory evoked
potential techniques) or estimated hearing ranges (behavioral response
data, anatomical modeling, etc.). Note that no direct measurements of
hearing ability have been successfully completed for mysticetes (i.e.,
low-frequency cetaceans). Subsequently, NMFS (2018) described
generalized hearing ranges for these marine mammal hearing groups.
Generalized hearing ranges were chosen based on the approximately 65
decibel (dB) threshold from the normalized composite audiograms, with
the exception for lower limits for low-frequency cetaceans where the
lower bound was deemed to be biologically implausible and the lower
bound from Southall et al. (2007) retained. Marine mammal hearing
groups and their associated hearing ranges are provided in table 3.
Table 3--Marine Mammal Hearing Groups
[NMFS, 2018]
------------------------------------------------------------------------
Hearing group Generalized hearing range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen 7 Hz to 35 kHz.
whales).
Mid-frequency (MF) cetaceans 150 Hz to 160 kHz.
(dolphins, toothed whales, beaked
whales, bottlenose whales).
High-frequency (HF) cetaceans (true 275 Hz to 160 kHz.
porpoises, Kogia, river dolphins,
Cephalorhynchid,.
Lagenorhynchus cruciger & L.
australis).
Phocid pinnipeds (PW) (underwater) 50 Hz to 86 kHz.
(true seals).
Otariid pinnipeds (OW) (underwater) 60 Hz to 39 kHz.
(sea lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
composite (i.e., all species within the group), where individual
species' hearing ranges are typically not as broad. Generalized
hearing range chosen based on ~65 dB threshold from normalized
composite audiogram, with the exception for lower limits for LF
cetaceans (Southall et al., 2007) and PW pinniped (approximation).
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt,
2013).
For more detail concerning these groups and associated frequency
ranges, please see NMFS (2018) for a review of available information.
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
This section provides a discussion of the ways in which components
of the specified activity may impact marine mammals and their habitat.
The Estimated Take section later in this
[[Page 88879]]
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 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 whether those impacts are reasonably expected to, or reasonably
likely to, adversely affect the species or stock through effects on
annual rates of recruitment or survival.
Description of Sound Sources
The marine soundscape is comprised of both ambient and
anthropogenic sounds. Ambient sound is defined as the all-encompassing
sound in a given place and is usually a composite of sound from many
sources both near and far. The sound level of an area is defined by the
total acoustical energy being generated by known and unknown sources.
These sources may include physical (e.g., waves, wind, precipitation,
earthquakes, ice, atmospheric sound), biological (e.g., sounds produced
by marine mammals, fish, and invertebrates), and anthropogenic sound
(e.g., vessels, dredging, aircraft, construction).
The sum of the various natural and anthropogenic sound sources at
any given location and time--which comprise ``ambient'' or
``background'' sound--depends not only on the source levels (as
determined by current weather conditions and levels of biological and
shipping activity) but also on the ability of sound to propagate
through the environment. In turn, sound propagation is dependent on the
spatially and temporally varying properties of the water column and sea
floor, and is frequency-dependent. As a result of the dependence on a
large number of varying factors, ambient sound levels can be expected
to vary widely over both coarse and fine spatial and temporal scales.
Sound levels at a given frequency and location can vary by 10 to 20 dB
from day to day (Richardson et al., 1995). The result is that,
depending on the source type and its intensity, sound from the
specified activity may be a negligible addition to the local
environment or could form a distinctive signal that may affect marine
mammals.
In-water construction activities associated with the project would
include vibratory pile driving, vibratory pile removal, and DTH
drilling. The sounds produced by these activities fall into one of two
general sound types: impulsive and non-impulsive. Impulsive sounds
(e.g., explosions, gunshots, sonic booms, impact pile driving) are
typically transient, brief (less than 1 second), broadband, and consist
of high peak sound pressure with rapid rise time and rapid decay (ANSI,
1986; NIOSH, 1998; ANSI, 2005; NMFS, 2018). Non-impulsive sounds (e.g.,
aircraft, machinery operations such as drilling or dredging, vibratory
pile driving, and active sonar systems) can be broadband, narrowband or
tonal, brief or prolonged (continuous or intermittent), and typically
do not have the high peak sound pressure with raid rise/decay time that
impulsive sounds do (ANSI, 1995; NIOSH, 1998; NMFS, 2018). The
distinction between these two sound types is important because they
have differing potential to cause physical effects, particularly with
regard to hearing (e.g., Ward, 1997; Southall, et al. 2007).
Vibratory hammers install piles by vibrating them and allowing the
weight of the hammer to push them into the sediment. Vibratory hammers
produce significantly less sound than impact hammers. Peak sound
pressure levels (SPLs) may be 180 dB or greater, but are generally 10
to 20 dB lower than SPLs generated during impact pile driving of the
same-sized pile (Oestman, et al., 2009). Rise time is slower, reducing
the probability and severity of injury, and sound energy is distributed
over a greater amount of time (Nedwell and Edwards, 2002; Carlson, et
al., 2005).
DTH systems would also be used during the proposed construction. A
DTH hammer is essentially a drill bit that drills through the bedrock
using a rotating function like a normal drill, in concert with a
hammering mechanism operated by a pneumatic (or sometimes hydraulic)
component integrated into the DTH hammer to increase speed of progress
through the substrate (i.e., it is similar to a ``hammer drill'' hand
tool). The sounds produced by the DTH methods contain both a continuous
non-impulsive component from the drilling action and an impulsive
component from the hammering effect. Therefore, NMFS treats DTH systems
as both impulsive and continuous, non-impulsive sound source types
simultaneously.
The likely or possible impacts of Trident's proposed activities on
marine mammals could involve both non-acoustic and acoustic stressors.
Potential non-acoustic stressors could result from the physical
presence of the equipment and personnel; however, given there are no
known pinniped haul-out sites in the vicinity of the proposed project
site, visual and other non-acoustic stressors would be limited, and any
impacts to marine mammals are expected to primarily be acoustic in
nature.
Acoustic Effects
The introduction of anthropogenic noise into the aquatic
environment from pile driving or drilling is the primary means by which
marine mammals may be harassed from the Haines Borough specified
activity. In general, animals exposed to natural or anthropogenic sound
may experience physical and psychological effects, ranging in magnitude
from none to severe (Southall et al., 2007; Southall et al., 2019). In
general, exposure to pile driving or drilling noise has the potential
to result in auditory threshold shifts and behavioral reactions (e.g.,
avoidance, temporary cessation of foraging and vocalizing, changes in
dive behavior). Exposure to anthropogenic noise can also lead to non-
observable physiological responses, such an increase in stress
hormones. Additional noise in a marine mammal's habitat can mask
acoustic cues used by marine mammals to carry out daily functions, such
as communication and predator and prey detection. The effects of pile
driving or drilling noise on marine mammals are dependent on several
factors, including, but not limited to, sound type (e.g., impulsive vs.
non-impulsive), the species, age and sex class (e.g., adult male vs.
mom with calf), duration of exposure, the distance between the pile and
the animal, received levels, behavior at time of exposure, and previous
history with exposure (Wartzok et al., 2004; Southall et al., 2007).
Here we discuss physical auditory effects (threshold shifts) followed
by behavioral effects and potential impacts on habitat.
Auditory Effects
NMFS defines a noise-induced threshold shift (TS) as a change,
usually an increase, in the threshold of audibility at a specified
frequency or portion of an individual's hearing range above a
previously established reference level (NMFS, 2018). The amount of
threshold shift is customarily expressed in dB. A TS can be permanent
or temporary. As described in NMFS (2018a), there are numerous factors
to consider when examining the consequence of TS, including, but not
limited to, the signal temporal pattern (e.g., impulsive or non-
impulsive), likelihood an individual would be exposed for a long enough
duration or to a high enough level to induce a TS, the magnitude of the
TS, time to recovery (seconds to minutes or hours to
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days), the frequency range of the exposure (i.e., spectral content),
the hearing and vocalization frequency range of the exposed species
relative to the signal's frequency spectrum (i.e. how animal uses sound
within the frequency band of the signal; e.g. Kastelein et al., 2014),
and the overlap between the animal and the source (e.g. spatial,
temporal, and spectral). When considering auditory effects for
Trident's proposed activities, vibratory pile driving is considered a
non-impulsive source, while DTH drilling are considered to have both
non-impulsive and impulsive components.
Permanent Threshold Shift (PTS)--NMFS defines PTS as a permanent,
irreversible increase in the threshold of audibility at a specified
frequency or portion of an individual's hearing range above a
previously established reference level (NMFS, 2018). PTS does not
generally affect more than a limited frequency range, and an animal
that has incurred PTS has incurred some level of hearing loss at the
relevant frequencies; typically animals with PTS are not functionally
deaf (Richardson et al., 1995; Au and Hastings, 2008). Available data
from humans and other terrestrial mammals indicate that a 40 dB
threshold shift approximates PTS onset (Ward et al., 1958, Ward et al.,
1959; Ward, 1960; Kryter et al., 1966; Miller, 1974; Ahroon et al.,
1996; Henderson et al., 2008). PTS criteria for marine mammals are
estimates, as with the exception of a single study unintentionally
inducing PTS in a harbor seal (Kastak et al., 2008), there are no
empirical data measuring PTS in marine mammals largely due to the fact
that, for various ethical reasons, experiments involving anthropogenic
noise exposure at levels inducing PTS are not typically pursued or
authorized (NMFS, 2018).
Temporary Threshold Shift (TTS)--A temporary, reversible increase
in the threshold of audibility at a specified frequency or portion of
an individual's hearing range above a previously established reference
level (NMFS, 2018). Based on data from cetacean TTS measurements
(Southall et al., 2007; Southall et al., 2019), a TTS of 6 dB is
considered the minimum threshold shift clearly larger than any day-to-
day or session-to-session variation in a subject's normal hearing
ability (Schlundt et al., 2000; Finneran et al., 2000; Finneran et al.,
2002). As described in Finneran (2015), marine mammal studies have
shown the amount of TTS increases with cumulative SEL
(SEL<INF>cum</INF>) in an accelerating fashion: at low exposures with
lower SELcum, the amount of TTS is typically small and the growth
curves have shallow slopes. At exposures with higher SEL<INF>cum</INF>,
the growth curves become steeper and approach linear relationships with
the noise SEL.
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 (similar to those discussed in auditory
masking, below). 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 animal
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 time when
communication is critical for successful mother/calf interactions could
have more serious impacts. We note that reduced hearing sensitivity as
a simple function of aging has been observed in marine mammals, as well
as humans and other taxa (Southall et al., 2007), so we can infer that
strategies exist for coping with this condition to some degree, though
likely not without cost.
Many studies have examined noise-induced hearing loss in marine
mammals (see Finneran (2015) and Southall et al. (2019) for summaries).
TTS is the mildest form of hearing impairment that can occur during
exposure to sound (Kryter, 2013). While experiencing TTS, the hearing
threshold rises, and a sound must be at a higher level in order to be
heard. In terrestrial and marine mammals, TTS can last from minutes or
hours to days (in cases of strong TTS). In many cases, hearing
sensitivity recovers rapidly after exposure to the sound ends. For
cetaceans, published data on the onset of TTS are limited to captive
bottlenose dolphin (Tursiops truncatus), beluga whale (Delphinapterus
leucas), harbor porpoise, and Yangtze finless porpoise (Neophocoena
asiaeorientalis) (Southall et al., 2019). For pinnipeds in water,
measurements of TTS are limited to harbor seals, elephant seals
(Mirounga angustirostris), bearded seals (Erignathus barbatus), and
California sea lions (Zalophus californianus) (Kastak et al., 1999;
Kastak et al., 2007; Kastelein et al., 2019b; Kastelein et al., 2019c;
Reichmuth et al., 2019; Sills et al., 2020; Kastelein et al., 2021;
Kastelein et al., 2022a; Kastelein et al., 2022b). These studies
examine hearing thresholds measured in marine mammals before and after
exposure to intense or long-duration sound exposures. The difference
between the pre-exposure and post-exposure thresholds can be used to
determine the amount of threshold shift at various post-exposure times.
The amount and onset of TTS depends on the exposure frequency.
Sounds at low frequencies, well below the region of best sensitivity
for a species or hearing group, are less hazardous than those at higher
frequencies, near the region of best sensitivity (Finneran and
Schlundt, 2013). At low frequencies, onset-TTS exposure levels are
higher compared to those in the region of best sensitivity (i.e., a low
frequency noise would need to be louder to cause TTS onset when TTS
exposure level is higher), as shown for harbor porpoises and harbor
seals (Kastelein et al., 2019a; Kastelein et al., 2019c). Note that in
general, harbor seals and harbor porpoises have a lower TTS onset than
other measured pinniped or cetacean species (Finneran, 2015). In
addition, TTS can accumulate across multiple exposures, but the
resulting TTS will be less than the TTS from a single, continuous
exposure with the same SEL (Mooney et al., 2009; Finneran et al., 2010;
Kastelein et al., 2014; 2015). This means that TTS predictions based on
the total, cumulative SEL will overestimate the amount of TTS from
intermittent exposures, such as sonars and impulsive sources.
Nachtigall et al. (2018) describe measurements of hearing sensitivity
of multiple odontocete species (bottlenose dolphin, harbor porpoise,
beluga, and false killer whale (Pseudorca crassidens) when a relatively
loud sound was preceded by a warning sound. These captive animals were
shown to reduce hearing sensitivity when warned of an impending intense
sound. Based on these experimental observations of captive animals, the
authors suggest that wild animals may dampen their hearing during
prolonged exposures or if conditioned to anticipate intense sounds.
Another study showed that echo-locating animals (including odontocetes)
might have anatomical specializations that might allow for conditioned
hearing reduction and filtering of low-frequency ambient noise,
including increased stiffness and control of middle ear structures and
placement of inner ear structures (Ketten et al., 2021). Data available
on noise-induced hearing loss for mysticetes are currently lacking
(NMFS, 2018). Additionally, the existing marine mammal TTS data come
from a limited number of individuals within these species.
[[Page 88881]]
Relationships between TTS and PTS thresholds have not been studied
in marine mammals, and there is no PTS data for cetaceans, but such
relationships are assumed to be similar to those in humans and other
terrestrial mammals. PTS typically occurs at exposure levels at least
several decibels above (a 40-dB threshold shift approximates PTS onset;
e.g., Kryter et al., 1966; Miller, 1974) that inducing mild TTS (a 6-dB
threshold shift approximates TTS onset; e.g., Southall et al., 2007).
Based on data from terrestrial mammals, a precautionary assumption is
that the PTS thresholds for impulsive sounds (such as impact pile
driving pulses as received close to the source) are at least 6 dB
higher than the TTS threshold on a peak-pressure basis and PTS
cumulative sound exposure level thresholds are 15 to 20 dB higher than
TTS cumulative sound exposure level thresholds (Southall et al., 2007).
Given the higher level of sound or longer exposure duration necessary
to cause PTS as compared with TTS, it is considerably less likely that
PTS could occur.
Furthermore, installing piles for this project requires a
combination of vibratory pile driving and DTH drilling. For the
project, these activities would not occur at the same time and there
would likely be pauses in activities producing the sound during each
day. Given these pauses and that many marine mammals are likely moving
through the action area and not remaining for extended periods of time,
the potential for any TS declines.
Behavioral Effects
Exposure to noise from pile driving and removal also has the
potential to behaviorally disturb marine mammals. Available studies
show wide variation in response to underwater sound; therefore, it is
difficult to predict specifically how any given sound in a particular
instance might affect marine mammals perceiving the signal. If a marine
mammal does react briefly to an underwater sound by changing its
behavior or moving a small distance, the impacts of the change are
unlikely to be significant to the individual, let alone the stock or
population. However, if a sound source displaces marine mammals from an
important feeding or breeding area for a prolonged period, impacts on
individuals and populations could be significant (e.g., Lusseau and
Bejder, 2007; Weilgart, 2007; NRC, 2005; Southall et al., 2021).
Disturbance may result in changing durations of surfacing and
dives, number of blows per surfacing, or moving direction and/or speed;
reduced/increased vocal activities; changing/cessation of certain
behavioral activities (such as socializing or feeding); visible startle
response or aggressive behavior (such as tail/fluke slapping or jaw
clapping); avoidance of areas where sound sources are located.
Pinnipeds may increase their haul out time, possibly to avoid in-water
disturbance (Thorson and Reyff, 2006). Behavioral responses to sound
are highly variable and context-specific and any reactions depend on
numerous intrinsic and extrinsic factors (e.g., species, state of
maturity, experience, current activity, reproductive state, auditory
sensitivity, time of day), as well as the interplay between factors
(e.g., Richardson et al., 1995; Wartzok et al., 2003; Southall et al.,
2007, Southall et al. 2021; Weilgart, 2007; Archer et al., 2010).
Behavioral reactions can vary not only among individuals but also
within exposures of an individual, depending on previous experience
with a sound source, context, and numerous other factors (Ellison et
al., 2012; Southall et al., 2021), and can vary depending on
characteristics associated with the sound source (e.g., whether it is
moving or stationary, number of sources, distance from the source). In
general, pinnipeds seem more tolerant of, or at least habituate more
quickly to, potentially disturbing underwater sound than do cetaceans,
and generally seem to be less responsive to exposure to industrial
sound than most cetaceans. For a review of studies involving marine
mammal behavioral responses to sound, see: Southall et al., 2007; Gomez
et al., 2016; and Southall et al., 2021.
Disruption of feeding behavior can be difficult to correlate with
anthropogenic sound exposure, so it is usually inferred by observed
displacement from known foraging areas, the appearance of secondary
indicators (e.g., bubble nets or sediment plumes), or changes in dive
behavior. As for other types of behavioral response, the frequency,
duration, and temporal pattern of signal presentation, as well as
differences in species sensitivity, are likely contributing factors to
differences in response in any given circumstance (e.g., Croll et al.,
2001; Nowacek et al., 2004; Madsen et al., 2006; Yazvenko et al.,
2007). A determination of whether foraging disruptions incur fitness
consequences is informed by information on or estimates of the
energetic requirements of the affected individuals and the relationship
between prey availability, foraging effort and success, and the life
history stage of the animal.
The area likely impacted by the project is relatively small
compared to the available habitat in the surrounding waters of the Near
Island Channel.
Airborne Acoustic Effects--Pinnipeds that occur near the project
site could be exposed to airborne sounds associated with pile driving
and removal that have the potential to cause behavioral harassment,
depending on their distance from pile driving activities. Cetaceans are
not expected to be exposed to airborne sounds that would result in
harassment as defined under the MMPA.
Airborne noise would primarily be an issue for pinnipeds that are
swimming near the project site within the range of noise levels
exceeding the acoustic thresholds. We recognize that pinnipeds in the
water could be exposed to airborne sound that may result in behavioral
harassment when looking with their heads above water. Most likely,
airborne sound would cause behavioral responses similar to those
discussed above in relation to underwater sound. For instance,
anthropogenic sound could cause pinnipeds to exhibit changes in their
normal behavior, such as reduction in vocalizations, or cause them to
temporarily abandon the area and move further from the source. However,
these animals would previously have been ``taken'' because of exposure
to underwater sound above the behavioral harassment thresholds, which
are in all cases larger than those associated with airborne sound.
Thus, the behavioral harassment of these animals is already accounted
for in these estimates of potential take. Therefore, we do not believe
that authorization of incidental take resulting from airborne sound for
pinnipeds is warranted, and airborne sound is not discussed further
here.
Auditory Masking--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 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
[[Page 88882]]
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 of natural sounds can result when
human activities produce high levels of background sound at frequencies
important to marine mammals. 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.
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. It is important to
distinguish TTS and PTS, which persist after the sound exposure, from
masking, which occurs during the sound exposure. Because masking
(without resulting in TS) is not associated with abnormal physiological
function, it is not considered a physiological effect, but rather a
potential behavioral effect.
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) 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). Masking can be reduced in situations where the signal
and noise come from different directions (Richardson et al., 1995),
through amplitude modulation of the signal, or through other
compensatory behaviors (Houser and Moore, 2014). Masking can be tested
directly in captive species (e.g., Erbe, 2008), but in wild populations
it must be either modeled or inferred from evidence of masking
compensation. There are few studies addressing real-world masking
sounds likely to be experienced by marine mammals in the wild (e.g.,
Branstetter et al., 2013).
Masking affects both senders and receivers of acoustic signals and
can potentially have long-term chronic effects on marine mammals at the
population level as well as at the individual level. Low-frequency
ambient sound levels have increased by as much as 20 dB (more than
three times in terms of SPL) in the world's ocean from pre-industrial
periods, with most of the increase from distant commercial shipping
(Hildebrand, 2009). All anthropogenic sound sources, but especially
chronic and lower-frequency signals (e.g., from vessel traffic),
contribute to elevated ambient sound levels, thus intensifying masking.
Background sound levels in the project area are generally already
elevated due to the cruise ships, passenger ferries, charter and
commercial fishing vessels, barges, and freight vessels that frequent
the area. Marine Mammal Habitat Effects.
The proposed project would occur within the same footprint as
existing marine infrastructure. The nearshore habitat where the
proposed project would occur is an area of relatively high marine
vessel traffic. Most marine mammals do not generally use the area
within the immediate vicinity of the project area. Temporary,
intermittent, and short-term habitat alteration may result from
increased noise levels within the Level B harassment zones. Effects on
marine mammals will be limited to temporary displacement from pile
installation and removal noise, and effects on prey species will be
similarly limited in time and space.
Water Quality--Temporary and localized reduction in water quality
will occur as a result of in-water construction activities. Most of
this effect will occur during the installation and removal of piles and
bedrock removal when bottom sediments are disturbed. The installation
and removal of piles and bedrock removal will disturb bottom sediments
and may cause a temporary increase in suspended sediment in the project
area. During pile extraction, sediment attached to the pile moves
vertically through the water column until gravitational forces cause it
to slough off under its own weight. The small resulting sediment plume
is expected to settle out of the water column within a few hours.
Studies of the effects of turbid water on fish (marine mammal prey)
suggest that concentrations of suspended sediment can reach thousands
of milligrams per liter before an acute toxic reaction is expected
(Burton, 1993).
Impacts to water quality from DTH hammers are expected to be
similar to those described for pile driving. Impacts to water quality
would be localized and temporary and would have negligible impacts on
marine mammal habitat. Effects to turbidity and sedimentation are
expected to be short-term, minor, and localized. Since the currents are
strong in the area, following the completion of sediment-disturbing
activities, suspended sediments in the water column should dissipate
and quickly return to background levels in all construction scenarios.
Turbidity within the water column has the potential to reduce the level
of oxygen in the water and irritate the gills of prey fish species in
the proposed project area. However, turbidity plumes associated with
the project would be temporary and localized, and fish in the proposed
project area would be able to move away from and avoid the areas where
plumes may occur. Therefore, it is expected that the impacts on prey
fish species from turbidity, and therefore on marine mammals, would be
minimal and temporary. In general, the area likely impacted by the
proposed construction activities is relatively small compared to the
available marine mammal habitat in southeast Alaska.
Effects on Prey--Construction activities would produce continuous
(i.e., vibratory pile driving) and impulsive (i.e., impact driving)
sounds and a both continuous and impulsive sounds from DTH
installation. Fish react to sounds that are especially strong and/or
intermittent low-frequency sounds. Short duration, sharp sounds can
cause overt or subtle changes in fish behavior and local distribution.
Hastings and Popper (2005) identified several studies that suggest fish
may relocate to avoid certain areas of sound energy. Additional studies
have documented effects of pile driving on fish, although several are
based on studies in support of large, multiyear bridge construction
projects (e.g., Scholik and Yan, 2001, Scholik and Yan, 2002; Popper
and Hastings, 2009). Sound pulses at received levels may cause
noticeable changes in behavior (Pearson et al., 1992; Skalski et al.,
1992). SPLs of sufficient strength have been known to cause injury to
fish and fish mortality.
Impacts on marine mammal prey (i.e., fish or invertebrates) of the
immediate area due to the acoustic disturbance are possible. The
duration of fish or invertebrate avoidance or other disruption of
behavioral patterns in this area after pile driving stops is unknown,
[[Page 88883]]
but a rapid return to normal recruitment, distribution and behavior is
anticipated. Further, significantly large areas of fish and marine
mammal foraging habitat are available in the nearby vicinity in the
Near Island Channel.
The duration of the construction activities is relatively short,
with pile driving and removal activities expected last less than one-
year. Each day, construction would occur for no more than 12 hours
during the day and pile driving activities would be restricted to
daylight hours. The most likely impact to fish from pile driving
activities at the project area would be temporary behavioral avoidance
of the area. In general, impacts to marine mammal prey species are
expected to be minor and temporary due to the short timeframe for the
project.
Construction activities, in the form of increased turbidity, have
the potential to adversely affect fish in the project area. Increased
turbidity is expected to occur in the immediate vicinity (on the order
of 10 ft (3 m) or less) of construction activities. However, suspended
sediments and particulates are expected to dissipate quickly within a
single tidal cycle. Given the limited area affected and high tidal
dilution rates any effects on fish are expected to be minor or
negligible. In addition, best management practices would be in effect,
which would limit the extent of turbidity to the immediate project
area.
In summary, given the relatively short daily duration of sound
associated with individual pile driving and events and the relatively
small areas being affected, pile driving activities associated with the
proposed action are not likely to have a permanent, adverse effect on
any fish habitat, or populations of fish species. Thus, we conclude
that impacts of the specified activity are not likely to have more than
short-term adverse effects on any prey habitat or populations of prey
species. Further, any impacts to marine mammal habitat are not expected
to result in significant or long-term consequences for individual
marine mammals, or to contribute to adverse impacts on their
populations.
Estimated Take
This section provides an estimate of the number of incidental takes
proposed for authorization through the IHA, which will inform both
NMFS' consideration of ``small numbers,'' and the negligible impact
determinations. Harassment is the only type of take expected to result
from these activities. Except with respect to certain activities not
pertinent here, section 3(18) of the MMPA defines ``harassment'' as any
act of pursuit, torment, or annoyance, which (i) has the potential to
injure a marine mammal or marine mammal stock in the wild (Level A
harassment); or (ii) has the potential to disturb a marine mammal or
marine mammal stock in the wild by causing disruption of behavioral
patterns, including, but not limited to, migration, breathing, nursing,
breeding, feeding, or sheltering (Level B harassment).
Authorized takes would be by Level B harassment only, in the form
of disruption of behavioral patterns for individual marine mammals
resulting from exposure to pile driving activities. Based on the nature
of the activity, Level A harassment is neither anticipated nor proposed
to be authorized.
As described previously, no serious injury or mortality is
anticipated or proposed to be authorized for this activity. Below we
describe how the proposed take numbers are estimated.
For acoustic impacts, 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) the number of days of activities. We note
that while these factors can contribute to a basic calculation to
provide an initial prediction of potential 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 estimates.
Acoustic Thresholds
NMFS recommends the use of acoustic thresholds that identify the
received level of underwater sound above which exposed marine mammals
would be reasonably expected to be behaviorally harassed (equated to
Level B harassment) or to incur PTS of some degree (equated to Level A
harassment).
Level B Harassment--Though significantly driven by received level,
the onset of behavioral disturbance from anthropogenic noise exposure
is also informed to varying degrees by other factors related to the
source or exposure context (e.g., frequency, predictability, duty
cycle, duration of the exposure, signal-to-noise ratio, distance to the
source), the environment (e.g., bathymetry, other noises in the area,
predators in the area), and the receiving animals (hearing, motivation,
experience, demography, life stage, depth) and can be difficult to
predict (e.g., Southall et al., 2007, 2021, Ellison et al., 2012).
Based on what the available science indicates and the practical need to
use a threshold based on a metric that is both predictable and
measurable for most activities, NMFS typically uses a generalized
acoustic threshold based on received level to estimate the onset of
behavioral harassment. NMFS generally predicts that marine mammals are
likely to be behaviorally harassed in a manner considered to be Level B
harassment when exposed to underwater anthropogenic noise above root-
mean-squared pressure received levels (RMS SPL) of 120 dB (referenced
to 1 micropascal (re 1 [mu]Pa)) for continuous (e.g., vibratory pile
driving, drilling) and above RMS SPL 160 dB re 1 [mu]Pa for non-
explosive impulsive (e.g., seismic airguns) or intermittent (e.g.,
scientific sonar) sources. Generally speaking, Level B harassment take
estimates based on these behavioral harassment thresholds are expected
to include any likely takes by TTS as, in most cases, the likelihood of
TTS occurs at distances from the source less than those at which
behavioral harassment is likely. TTS of a sufficient degree can
manifest as behavioral harassment, as reduced hearing sensitivity and
the potential reduced opportunities to detect important signals
(conspecific communication, predators, prey) may result in changes in
behavior patterns that would not otherwise occur.
Trident's proposed activity includes the use of continuous
(vibratory pile driving) sources, and therefore the RMS SPL threshold
of 120 dB re 1 [mu]Pa is applicable. DTH drilling has both continuous
and intermittent (impulsive) components as discussed in the Description
of Sound Sources section above. When evaluating Level B harassment,
NMFS recommends treating DTH as a continuous source and applying the
RMS SPL thresholds of 120 dB re 1 [mu]Pa.
Level A Harassment--NMFS' Technical Guidance for Assessing the
Effects of Anthropogenic Sound on Marine Mammal Hearing (Version 2.0)
(Technical Guidance, 2018) identifies dual criteria to assess auditory
injury (Level A harassment) to five different marine mammal groups
(based on hearing sensitivity) as a result of exposure to noise from
two different types of sources (impulsive or non-impulsive). Trident's
proposed activity includes the use of non-impulsive
[[Page 88884]]
(vibratory pile driving) sources. As described above, DTH includes both
impulsive and non-impulsive characteristics. When evaluating Level A
harassment, NMFS recommends treating DTH as an impulsive source.
These thresholds are provided in the table below. The references,
analysis, and methodology used in the development of the thresholds are
described in NMFS' 2018 Technical Guidance, which may be accessed at:
<a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance</a>.
Table 4--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
PTS onset thresholds * (received level)
Hearing group ------------------------------------------------------------------------
Impulsive Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans........... Cell 1: L0-pk,flat: 219 Cell 2: LE,LF,24h: 199 dB.
dB; LE, LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans........... Cell 3: L0-pk,flat: 230 Cell 4: LE,MF,24h: 198 dB.
dB; LE, MF,24h: 185 dB.
High-Frequency (HF) Cetaceans.......... Cell 5: L0-pk,flat: 202 Cell 6: LE,HF,24h: 173 dB.
dB; LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater)..... Cell 7: L0-pk,flat: 218 Cell 8: LE,PW,24h: 201 dB.
dB; LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater).... Cell 9: L0-pk,flat: 232 Cell 10: LE,OW,24h: 219 dB.
dB; LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric 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 are recommended for consideration.
Note: Peak sound pressure level (L0-pk) has a reference value of 1 [mu]Pa, and weighted cumulative sound
exposure level (LE,) has a reference value of 1[mu]Pa\2\s. In this table, thresholds are abbreviated to be
more reflective of International Organization for Standardization standards (ISO 2017). The subscript ``flat''
is being included to indicate peak sound pressure are flat weighted or unweighted within the generalized
hearing range of marine mammals (i.e., 7 Hz to 160 kHz). 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 weighted
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 thresholds will be exceeded.
Ensonified Area
Here, we describe operational and environmental parameters of the
activity that are used in estimating the area ensonified above the
acoustic thresholds, including source levels and transmission loss
coefficient.
The sound field in the project area is the existing background
noise plus additional construction noise from the proposed project.
Marine mammals are expected to be affected via sound generated by the
primary components of the project (i.e., vibratory pile driving and
removal, DTH drilling). The maximum (underwater) area ensonified above
the thresholds for behavioral harassment referenced above is 125 km\2\
(48.26 mi\2\), that would be truncated by land masses that would
obstruct underwater sound transmission and would extend into Near
Island Channel and St. Paul Harbor (see figure 5 in Trident's
application). Additionally, vessel traffic and other commercial and
industrial activities in the project area may contribute to elevated
background noise levels which may mask sounds produced by the project.
Transmission loss (TL) is the decrease in acoustic intensity as an
acoustic pressure wave propagates out from a source. TL parameters vary
with frequency, temperature, sea conditions, current, source and
receiver depth, water depth, water chemistry, and bottom composition
and topography. The general formula for underwater TL is:
TL = B * Log<INF>10</INF> (R<INF>1</INF>/R<INF>2</INF>),
where
TL = transmission loss in dB
B = transmission loss coefficient
R<INF>1</INF> = the distance of the modeled SPL from the driven
pile, and
R<INF>2</INF> = the distance from the driven pile of the initial
measurement
This formula neglects loss due to scattering and absorption, which
is assumed to be zero here. The degree to which underwater sound
propagates away from a sound source is dependent on a variety of
factors, most notably the water bathymetry and presence or absence of
reflective or absorptive conditions including in-water structures and
sediments. Spherical spreading occurs in a perfectly unobstructed
(free-field) environment not limited by depth or water surface,
resulting in a 6-dB reduction in sound level for each doubling of
distance from the source (20*log[range]). Cylindrical spreading occurs
in an environment in which sound propagation is bounded by the water
surface and sea bottom, resulting in a reduction of 3 dB in sound level
for each doubling of distance from the source (10*log[range]). A
practical spreading value of 15 is often used under conditions, such as
the project site, where water increases with depth as the receiver
moves away from the shoreline, resulting in an expected propagation
environment that would lie between spherical and cylindrical spreading
loss conditions. Practical spreading loss is assumed here.
The intensity of pile driving sounds is greatly influenced by
factors such as the type of piles, hammers, and the physical
environment in which the activity takes place. In order to calculate
the distances to the Level A harassment and the Level B harassment
sound thresholds for the methods and piles being used in this project,
the applicant and NMFS used acoustic monitoring data from other
locations to develop proxy source levels for the various pile types,
sizes and methods. The project includes vibratory and DTH pile
installation of steel pipe piles and vibratory removal of steel pipe
piles, steel H-piles, and timber piles. Source levels for each pile
size and driving method are presented in table 5.
[[Page 88885]]
Table 5--Proxy Sound Source Levels for Pile Sizes and Driving Methods
----------------------------------------------------------------------------------------------------------------
Installation or RMS SPL (re 1 SEL (re 1
Pile type removal [mu]Pa) [mu]Pa\2\-sec) Source
----------------------------------------------------------------------------------------------------------------
Vibratory Pile Driving
----------------------------------------------------------------------------------------------------------------
14-in timber pile................ Removal............. 162 NA Caltrans 2020.
14-in H-pile..................... Removal............. 150 Caltrans 2020.
16-in steel pile................. Installation........ 161 NAVFAC 2015.
16-in steel pile................. Removal............. NAVFAC 2015.
24-in steel pile................. Installation........ NAVFAC 2015.
----------------------------------------------------------------------------------------------------------------
DTH Drilling \1\
----------------------------------------------------------------------------------------------------------------
16-in steel pile................. Installation........ 162 141 Heyvaert & Reyff
2021, Guan & Miner
2020.
24-in steel pile................. Installation........ 154 Heyvaert & Reyff
2021.
----------------------------------------------------------------------------------------------------------------
\1\ Sound source levels for DTH were adjusted by -5 dB to reflect the use of the bubble curtain.
The ensonified area associated with Level A harassment is more
technically challenging to predict due to the need to account for a
duration component. Therefore, NMFS developed an optional User
Spreadsheet tool to accompany the Technical Guidance that can be used
to relatively simply predict an isopleth distance for use in
conjunction with marine mammal density or occurrence to help predict
potential takes. We note that because of some of the assumptions
included in the methods underlying this optional tool, we anticipate
that the resulting isopleth estimates are typically going to be
overestimates of some degree, which may result in an overestimate of
potential take by Level A harassment. However, this optional tool
offers the best way to estimate isopleth distances when more
sophisticated modeling methods are not available or practical. For
stationary sources such as pile driving, the optional User Spreadsheet
tool predicts the distance at which, if a marine mammal remained at
that distance for the duration of the activity, it would be expected to
incur PTS. Inputs used in the optional User Spreadsheet tool, and the
resulting estimated isopleths, are reported below.
Table 6--NMFS User Spreadsheet Inputs
----------------------------------------------------------------------------------------------------------------
Weighting
factor Transmission Number of Activity
Pile size and type Spreadsheet tab used adjustment loss piles per day duration
(kHz) coefficient (minutes)
----------------------------------------------------------------------------------------------------------------
14-in timber pile vibratory A.1 Vibratory pile 2.5 15 25 2
removal. driving.
14-in steel H-pile vibratory A.1 Vibratory pile 2.5 15 20 2
removal. driving.
16-in steel pipe pile vibratory A.1 Vibratory pile 2.5 15 20 2
removal. driving.
16-in steel pipe pile vibratory A.1 Vibratory pile 2.5 15 5 2
installation. driving.
24-in steel pipe pile vibratory A.1 Vibratory pile 2.5 15 6 2
installation (temporary). driving.
24-in steel pipe pile vibratory A.1 Vibratory pile 2.5 15 8 2
removal (temporary). driving.
24-in steel pipe pile vibratory A.1 Vibratory pile 2.5 15 4 2
installation. driving.
16-in steel pipe pile DTH E.2 DTH pile driving 2 15 6 45
installation.
24-in steel pipe pile DTH E.2 DTH pile driving 2 15 6 30
installation (temporary).
24-in steel pipe pile DTH E.2 DTH pile driving 2 15 4 60
installation.
----------------------------------------------------------------------------------------------------------------
Table 7--Calculated Level A and Level B Harassment Isopleths
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level A harassment zone (m) Level B
Activity -------------------------------------------------------------------------------- harassment
LF-cetaceans MF-cetaceans HF-cetaceans Otariids Phocids zone (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
14-in timber pile vibratory removal..................... 7.1 0.6 10.4 4.3 0.3 6,310
14-in steel H-pile vibratory removal.................... 1.0 0.1 1.4 0.6 0.0 1,000
16-in steel pipe pile vibratory removal................. 5.2 0.5 7.7 3.2 0.2 5,415
16-in steel pipe pile vibratory installation............ 2.1 0.2 3.1 1.3 0.1
24-in steel pipe pile vibratory installation (temporary) 2.3 0.2 3.5 1.4 0.1
24-in steel pipe pile vibratory removal (temporary)..... 2.8 0.3 4.2 1.7 0.1
24-in steel pipe pile vibratory installation............ 1.8 0.2 2.6 1.1 0.1
16-in steel pipe pile DTH installation.................. 47.0 1.7 56.0 1.8 25.2 6,310
24-in steel pipe pile DTH installation (temporary)...... 264.1 9.4 314.5 10.3 141.3
24-in steel pipe pile DTH installation.................. 319.9 11.4 381.0 12.5 171.2
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 88886]]
Marine Mammal Occurrence and Take Estimation
In this section we provide information about the occurrence of
marine mammals, including density or other relevant information which
will inform the take calculations.
When available, peer-reviewed scientific publications were used to
estimate marine mammal abundance in the project area. Data from
monitoring reports from projects on the Kodiak Ferry Terminal were used
as well as reports from other projects in Kodiak, Alaska.
Here we describe how the information provided above is synthesized
to produce a quantitative estimate of the take that is reasonably
likely to occur and proposed for authorization. Tables for each species
are presented to show the calculation of take during the project. Both
density and occurrence data was considered in incidental take
estimations. Density data were used when there was no occurrence data
available, or when occurrence and density data were similar. The take
calculations for this project are:
Incidental take estimate = group size * days of pile driving activity
Or
Incidental take estimate = (Activity Level B harassment area [km\2\] x
estimated density [individuals/km\2\]) x days of pile driving activity
Humpback Whale
Humpback whales are present in Kodiak year-round with peaks in the
spring and fall. They are considered common in the project area,
meaning there are multiple sightings every month, so they could occur
daily in the project's action. In the proposed project area humpback
whales are expected to occur at a density of 0.093 individuals per
square kilometer area (Halpin et al. 2009). Therefore, using the
equation given above, the total number of Level B harassment takes for
humpback whales would be 14. In the action area it is estimated that
the majority of whales (89 percent) will be from the Hawaii DPS, 11
percent will be from the Mexico DPS, and 1 percent will be from the
endangered Western North Pacific DPS (Wade 2021; Muto et al. 2022).
Therefore 13 takes are assumed to be from the Hawaii DPS and 1 take
from the Mexico DPS.
The largest Level A harassment zone for humpback whales extends
319.9 m from the noise source (table 7). All construction work would be
shut down prior to a humpback whale entering the Level A harassment
zone specific to the in-water activity underway at the time. In
consideration of the infrequent occurrence of humpback whales in the
project area and proposed shutdown requirements, no take by Level A
harassment is anticipated or proposed for humpback whales.
Killer Whale
Killer whales are present in Kodiak year-round and are considered
common in the project area, meaning there are multiple sightings every
month, so they could occur daily in the project's action. A single
group of up to six killer whales are expected to occur in the proposed
project area daily (Halpin et al. 2009). Therefore, using the equation
given above, the total number of Level B harassment takes for killer
whales would be 330. In the action area it is estimated that the
majority of killer whales (80 percent) will be from the Alaska resident
stock and 20 percent will be from the Gulf of Alaska/Aleutian Islands/
Bering Sea transient stock (Muto et al. 2022). Therefore 264 takes are
assumed to be from the Alaska resident stock and 66 takes firm the Gulf
of Alaska/Aleutian Islands/Bering Sea transient stock.
The largest Level A harassment zone for killer whales extends 11.4
m from the noise source (table 7). All construction work would be shut
down prior to a killer whale entering the Level A harassment zone
specific to the in-water activity underway at the time. In
consideration of the small size of the Level A harassment zone and
proposed shutdown requirements, no take by Level A harassment is
anticipated or proposed for killer whale.
Harbor Porpoise
Harbor porpoises are present in Kodiak year-round and are occur
frequently in the project area, meaning there are multiple sightings
every year, so they could occur monthly in the project's action. In the
proposed project area harbor porpoises are expected to occur at a
density of 0.4547 individuals per square kilometer area (Marine
Geospatial Ecology Lab 2021). Therefore, using the equation given
above, the total number of Level B harassment takes for harbor
porpoises would be 65.
The largest Level A harassment zone for harbor porpoise extends 381
m from the noise source (table 7). All construction work would be shut
down prior to a harbor porpoise entering the Level A harassment zone
specific to the in-water activity underway at the time. In
consideration of the relatively low anticipated exposure in the project
area and the anticipated effectiveness of the proposed shutdown
requirements, no take by Level A harassment is anticipated or proposed
for harbor porpoise.
Dall's Porpoise
Dall's porpoises are present in Kodiak year-round and are occur
frequently in the project area, meaning there are multiple sightings
every year, so they could occur monthly in the project's action. In the
proposed project area Dall's porpoises are expected to occur at a
density of 0.218 individuals per square kilometer area (Marine
Geospatial Ecology Lab 2021). Therefore, using the equation given
above, the total number of Level B harassment takes for Dall's porpoise
would be 31.
The largest Level A harassment zone for Dall's porpoise extends 381
m from the noise source (table 7). All construction work would be shut
down prior to a Dall's porpoise entering the Level A harassment zone
specific to the in-water activity underway at the time. In
consideration of the relatively low anticipated exposure in the project
area and the anticipated effectiveness of the proposed shutdown
requirements, no take by Level A harassment is anticipated or proposed
for Dall's porpoise.
Harbor Seal
Harbor seals are present in Kodiak year-round and are considered
common in the project area, meaning there are multiple sightings every
month, so they could occur daily in the project's action. In the
proposed project area Dall's porpoises are expected to occur at a
density of 0.1689 individuals per square kilometer area (Marine
Geospatial Ecology Lab 2021). Therefore, using the equation given
above, the total number of Level B harassment takes for harbor seals
would be 24.
The largest Level A harassment zone for harbor seals extends 171.2
m from the noise source (table 7). All construction work would be shut
down prior to a harbor seal entering the Level A harassment zone
specific to the in-water activity underway at the time. In
consideration of the relatively low anticipated exposure in the project
area and the anticipated effectiveness of the proposed shutdown
requirements, no take by Level A harassment is anticipated or proposed
for harbor seals.
Steller Sea Lion
Steller sea lions are present in Kodiak year-round and are
considered common in the project area, meaning there are multiple
sightings every month, so they could occur daily in the project's
action. During construction at the Kodiak Ferry
[[Page 88887]]
Terminal (82 FR 10894, February 26, 2017) Steller sea lions were
encountered daily during construction. Up to 40 Steller sea lions are
expected to occur in the proposed project area daily (Marine Geospatial
Ecology Lab 2021). Therefore, using the equation given above, the total
number of Level B harassment takes for Steller sea lions would be
2,200.
The largest Level A harassment zone for harbor seals extends 12.5 m
from the noise source (table 7). All construction work would be shut
down prior to a Steller sea lion entering the Level A harassment zone
specific to the in-water activity underway at the time. In
consideration of the small Level A harassment isopleth and proposed
shutdown requirements, no take by Level A harassment is anticipated or
proposed for Steller sea lions.
Table 8--Estimated Take by Level A and Level B Harassment, by Species and Stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Proposed take
Common name Stock Stock Level A Level B Total proposed as percentage
abundance \a\ harassment harassment take of stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale............................ Central North Pacific....... 10,103 0 12 13 0.1
CA/OR/WA.................... 4,973 0 2 1 0.07
Killer Whale.............................. Alaska Resident............. 1,920 0 264 264 13.8
Gulf of Alaska/Aleutian 587 0 66 66 11.2
Islands/Bering Sea
Transient.
Harbor porpoise........................... Gulf of Alaska.............. 31,946 0 65 65 0.08
Dall's porpoise........................... Alaska...................... 13,110 0 31 31 0.24
Steller sea lion.......................... Western U.S................. 52,932 0 2,200 2,200 4.2
Harbor seal............................... South Kodiak Island......... 26,448 0 24 24 0.09
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Stock size is Nbest according to NMFS 2022 Stock Assessment Reports.
Proposed Mitigation
In order to issue an IHA under section 101(a)(5)(D) of the MMPA,
NMFS must set forth the permissible methods of taking pursuant to the
activity, and other means of effecting the least practicable impact on
the species or stock and its habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance, and on
the availability of the species or stock for taking for certain
subsistence uses. NMFS regulations require applicants for incidental
take authorizations to include information about the availability and
feasibility (economic and technological) of equipment, methods, and
manner of conducting the activity or other means of effecting the least
practicable adverse impact upon the affected species or stocks, and
their habitat (50 CFR 216.104(a)(11)).
In evaluating how mitigation may or may not be appropriate to
ensure the least practicable adverse impact on species or stocks and
their habitat, as well as subsistence uses where applicable, NMFS
considers two primary factors:
(1) The manner in which, and the degree to which, the successful
implementation of the measure(s) is expected to reduce impacts to
marine mammals, marine mammal species or stocks, and their habitat, as
well as subsistence uses. This considers the nature of the potential
adverse impact being mitigated (likelihood, scope, range). It further
considers the likelihood that the measure will be effective if
implemented (probability of accomplishing the mitigating result if
implemented as planned), the likelihood of effective implementation
(probability implemented as planned), and;
(2) The practicability of the measures for applicant
implementation, which may consider such things as cost, and impact on
operations.
In addition to the measures described later in this section,
Trident would employ the following standard mitigation measures:
<bullet> At the start of each day, the Contractor(s) would hold a
briefing with the Lead Protected Species Observer (PSO) to outline the
activities planned for that day.
<bullet> If poor weather conditions restrict the PSO's ability to
make observations within the Level A harassment zone of pile driving
(e.g., if there is excessive wind or fog), pile installation and
removal would be halted.
The following measures would apply to Trident's mitigation
requirements:
Shutdown and Monitoring Zones
Trident must establish shutdown zones and Level B monitoring zones
for all pile driving activities. The purpose of a shutdown zone is
generally to define an area within which shutdown of the activity would
occur upon sighting of a marine animal (or in anticipation of an animal
entering the defined area). Shutdown zones are based on the largest
Level A harassment zone for each pile size/type and driving method, and
behavioral monitoring zones are meant to encompass Level B harassment
zones for each pile size/type and driving method, as shown in table 9.
A minimum shutdown zone of 10 m would be required for all in-water
construction activities to avoid physical interaction with marine
mammals. Marine mammal monitoring will be conducted during all pile
driving activities to ensure that marine mammals do not enter Level A
shutdown zones, that marine mammal presence in the isopleth does not
exceed authorized take. Proposed shutdown zones for each activity type
are shown in table 9.
Prior to pile driving, shutdown zones and monitoring zones will be
established based on zones represented in table 9. Observers will
survey the shutdown zones for at least 30 minutes before pile driving
activities start. If marine mammals are found within the shutdown zone,
pile driving will be delayed until the animal has moved out of the
shutdown zone, either verified by an observer or by waiting until 15
minutes has elapsed without a sighting. If a marine mammal approaches
or enters the shutdown zone during pile driving, the activity will be
halted. Pile driving may resume after the animal has moved out of and
is moving away from the shutdown zone or after at least 15 minutes has
passed since the last observation of the animal.
All marine mammals would be monitored in the Level B harassment
zones and throughout the area as far as visual monitoring can take
place. If a marine mammal enters the Level B harassment zone, in-water
activities would continue and PSOs would document the animal's presence
within the estimated harassment zone.
[[Page 88888]]
If a species for which authorization has not been granted, or a
species which has been granted but the authorized takes are met, is
observed approaching or within the Level B harassment zone, pile
driving activities will be shutdown immediately. Activities will not
resume until the animal has been confirmed to have left the area or 15
minutes has elapsed with no sighting of the animal.
Table 9--Shutdown and Level B Harassment Zones by Activity
--------------------------------------------------------------------------------------------------------------------------------------------------------
Minimum shutdown zone
-------------------------------------------------------------------------------- Level B
Pile size, type, and method High- harassment
Low-frequency Mid-frequency frequency Phocid Otariid zone
--------------------------------------------------------------------------------------------------------------------------------------------------------
Barge movements, pile positioning, ect.................. 10 10 10 10 10 10
14-in timber pile vibratory removal..................... 10 10 15 10 10 6,310
14-in steel H-pile vibratory removal.................... 10 10 10 10 10 1,000
16-in steel pipe pile vibratory removal................. 10 10 10 10 10 5,415
16-in steel pipe pile vibratory installation............ 10 10 10 10 10 5,415
24-in steel pipe pile vibratory installation (temporary) 10 10 10 10 10 5,415
24-in steel pipe pile vibratory removal (temporary)..... 10 10 10 10 10 5,415
24-in steel pipe pile vibratory installation............ 10 10 10 10 10 5,415
16-in steel pipe pile DTH installation.................. 50 10 60 30 10 6,310
24-in steel pipe pile DTH installation (temporary)...... 265 10 315 145 15 6,310
24-in steel pipe pile DTH installation.................. 320 15 385 175 15 6,310
--------------------------------------------------------------------------------------------------------------------------------------------------------
Protected Species Observers
The placement of PSOs during all pile driving activities (described
in the Proposed Monitoring and Reporting section) would ensure that the
entire shutdown zone is visible. Should environmental conditions
deteriorate such that the entire shutdown zone would not be visible
(e.g., fog, heavy rain), pile driving would be delayed until the PSO is
confident marine mammals within the shutdown zone could be detected.
PSOs would monitor the full shutdown zones and as much of the Level
B harassment zones as possible. Monitoring zones provide utility for
observing by establishing monitoring protocols for areas adjacent to
the shutdown zones. Monitoring enables observers to be aware of and
communicate the presence of marine mammals in the project areas outside
the shutdown zones and thus prepare for a potential cessation of
activity should the animal enter the shutdown zone.
Pre- and Post-Activity Monitoring
Monitoring must take place from 30 minutes prior to initiation of
pile driving activities (i.e., pre-clearance monitoring) through 30
minutes post-completion of pile driving. Prior to the start of daily
in-water construction activity, or whenever a break in pile driving of
30 minutes or longer occurs, PSOs would observe the shutdown and
monitoring zones for a period of 30 minutes. The shutdown zone would be
considered cleared when a marine mammal has not been observed within
the zone for a 30-minute period. If a marine mammal is observed within
the shutdown zones, pile driving activity would be delayed or halted.
If work ceases for more than 30 minutes, the pre-activity monitoring of
the shutdown zones would commence. A determination that the shutdown
zone is clear must be made during a period of good visibility (i.e.,
the entire shutdown zone and surrounding waters must be visible to the
naked eye).
Bubble Curtain
A bubble curtain must be employed during all impact DTH activities
to interrupt the acoustic pressure and reduce impact on marine mammals.
The bubble curtain must distribute air bubbles around 100 percent of
the piling circumference for the full depth of the water column. The
lowest bubble ring must be in contact with the mudline for the full
circumference of the ring. The weights attached to the bottom ring must
ensure 100 percent substrate contact. No parts of the ring or other
objects may prevent full substrate contact. Air flow to the bubblers
must be balanced around the circumference of the pile.
Based on our evaluation of the applicant's proposed measures, NMFS
has preliminarily determined that the proposed mitigation measures
provide the means of effecting the least practicable impact on the
affected species or stocks and their habitat, paying particular
attention to rookeries, mating grounds, and areas of similar
significance.
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 while
conducting the activities. 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:
<bullet> Occurrence of marine mammal species or stocks in the area
in which take is anticipated (e.g., presence, abundance, distribution,
density);
<bullet> 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 activity; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
[[Page 88889]]
<bullet> Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors;
<bullet> How anticipated responses to stressors impact either: (1)
long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks;
<bullet> Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important physical components of
marine mammal habitat); and,
<bullet> Mitigation and monitoring effectiveness.
Visual Monitoring
Monitoring shall be conducted by NMFS-approved observers in
accordance with the monitoring plan and Section 5 of the IHA. Trained
observers shall be placed from the best vantage point(s) practicable to
monitor for marine mammals and implement shutdown or delay procedures
when applicable through communication with the equipment operator.
Observer training must be provided prior to project start, and shall
include instruction on species identification (sufficient to
distinguish the species in the project area), description and
categorization of observed behaviors and interpretation of behaviors
that may be construed as being reactions to the specified activity,
proper completion of data forms, and other basic components of
biological monitoring, including tracking of observed animals or groups
of animals such that repeat sound exposures may be attributed to
individuals (to the extent possible).
Monitoring would be conducted 30 minutes before, during, and 30
minutes after pile driving/removal activities. In addition, observers
shall record all incidents of marine mammal occurrence, regardless of
distance from activity, and shall document any behavioral reactions in
concert with distance from piles being driven or removed. Pile driving/
removal activities include the time to install or remove a single pile
or series of piles, as long as the time elapsed between uses of the
pile driving equipment is no more than 30 minutes.
Between one and five PSOs will be on duty depending on the size of
the monitoring zone. Locations from which PSOs would be able to monitor
for marine mammals are readily available from publicly accessible
shoreside areas at the Near Island Channel and surrounding waters.
Monitoring locations would be selected by the Contractor during pre-
construction. PSOs would monitor for marine mammals entering the Level
B harassment zones; the position(s) may vary based on construction
activity and location of piles or equipment.
PSOs would scan the waters using binoculars, and/or spotting
scopes, and would use a handheld range-finder device to verify the
distance to each sighting from the project site. All PSOs would be
trained in marine mammal identification and behaviors and are required
to have no other project-related tasks while conducting monitoring. In
addition, monitoring would be conducted by qualified observers, who
would be placed at the best vantage point(s) practicable to monitor for
marine mammals and implement shutdown/delay procedures when applicable
by calling for the shutdown to the hammer operator via a radio. Trident
would adhere to the following observer qualifications:
(i) Independent observers (i.e., not construction personnel) are
required;
(ii) One PSO would be designated as the lead PSO or monitoring
coordinator and that observer must have prior experience working as an
observer;
(iii) Other observers may substitute education (degree in
biological science or related field) or training for experience; and
(iv) Trident must submit observer Curriculum Vitaes for approval by
NMFS.
Additional standard observer qualifications include:
<bullet> Ability to conduct field observations and collect data
according to assigned protocols;
<bullet> Experience or training in the field identification of
marine mammals, including the identification of behaviors;
<bullet> Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
<bullet> Writing skills sufficient to prepare a report of
observations including but not limited to the number and species of
marine mammals observed; dates and times when in-water construction
activities were conducted; dates and times when in-water construction
activities were suspended to avoid potential incidental injury from
construction sound of marine mammals observed within a defined shutdown
zone; and marine mammal behavior; and
<bullet> Ability to communicate orally, by radio or in person, with
project personnel to provide real-time information on marine mammals
observed in the area as necessary.
Data Collection
PSOs would use approved data forms to record the following
information:
<bullet> Dates and times (beginning and end) of all marine mammal
monitoring.
<bullet> PSO locations during marine mammal monitoring.
Construction activities occurring during each daily observation
period, including how many and what type of piles were driven or
removed and by what method (i.e., vibratory or DTH).
<bullet> Weather parameters and water conditions.
<bullet> The number of marine mammals observed, by species,
relative to the pile location and if pile driving or removal was
occurring at time of sighting.
<bullet> Distance and bearings of each marine mammal observed to
the pile being driven or removed.
<bullet> Description of marine mammal behavior patterns, including
direction of travel.
<bullet> Age and sex class, if possible, of all marine mammals
observed.
<bullet> Detailed information about implementation of any
mitigation triggered (such as shutdowns and delays), a description of
specific actions that ensued, and resulting behavior of the animal if
any.
Reporting
A draft marine mammal monitoring report would be submitted to NMFS
within 90 days after the completion of pile driving and removal
activities. It would include an overall description of work completed,
a narrative regarding marine mammal sightings, and associated PSO data
sheets. Specifically, the report must include:
<bullet> Dates and times (begin and end) of all marine mammal
monitoring.
<bullet> Construction activities occurring during each daily
observation period, including the number and type of piles driven or
removed and by what method (i.e., vibratory driving) and the total
equipment duration for cutting for each pile.
<bullet> PSO locations during marine mammal monitoring.
<bullet> Environmental conditions during monitoring periods (at
beginning and end of PSO shift and whenever conditions change
significantly), including Beaufort sea state and any other relevant
weather conditions including cloud cover, fog, sun glare, and overall
visibility to the horizon, and estimated observable distance;
<bullet> Upon observation of a marine mammal, the following
information: Name of PSO who sighted the animal(s) and PSO location and
activity at time of sighting; Time of sighting; Identification
[[Page 88890]]
of the animal(s) (e.g., genus/species, lowest possible taxonomic level,
or unidentified), PSO confidence in identification, and the composition
of the group if there is a mix of species; Distance and bearing of each
marine mammal observed relative to the pile being driven for each
sighting (if pile driving was occurring at time of sighting); Estimated
number of animals (min/max/best estimate); Estimated number of animals
by cohort (adults, juveniles, neonates, group composition, etc.);
Animal's closest point of approach and estimated time spent within the
harassment zone; Description of any marine mammal behavioral
observations (e.g., observed behaviors such as feeding or traveling),
including an assessment of behavioral responses thought to have
resulted from the activity (e.g., no response or changes in behavioral
state such as ceasing feeding, changing direction, flushing, or
breaching);
<bullet> Number of marine mammals detected within the harassment
zones, by species.
<bullet> Detailed information about any implementation of any
mitigation triggered (e.g., shutdowns and delays), a description of
specific actions that ensued, and resulting changes in behavior of the
animal(s), if any.
If no comments are received from NMFS within 30 days, the draft
final report would constitute the final report. If comments are
received, a final report addressing NMFS comments must be submitted
within 30 days after receipt of comments.
Reporting Injured or Dead Marine Mammals
In the unanticipated event that the specified activity clearly
causes the take of a marine mammal in a manner prohibited by the IHA
(if issued), such as an injury, serious injury or mortality, Trident
would immediately cease the specified activities and report the
incident to the Chief of the Permits and Conservation Division, Office
of Protected Resources, NMFS, and the Alaska Regional Stranding
Coordinator. The report would include the following information:
<bullet> Description of the incident;
<bullet> Environmental conditions (e.g., Beaufort sea state,
visibility);
<bullet> Description of all marine mammal observations in the 24
hours preceding the incident;
<bullet> Species identification or description of the animal(s)
involved;
<bullet> Fate of the animal(s); and
<bullet> 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 prohibited take. NMFS would work with Trident to
determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. Trident would not be able
to resume their activities until notified by NMFS via letter, email, or
telephone.
In the event that Trident discovers an injured or dead marine
mammal, and the lead PSO determines that the cause of the injury or
death is unknown and the death is relatively recent (e.g., in less than
a moderate state of decomposition as described in the next paragraph),
Trident would immediately report the incident to the Chief of the
Permits and Conservation Division, Office of Protected Resources, NMFS,
and the NMFS Alaska Stranding Hotline and/or by email to the Alaska
Regional Stranding Coordinator. The report would include the same
information identified in the paragraph above. Activities would be able
to continue while NMFS reviews the circumstances of the incident. NMFS
would work with Trident to determine whether modifications in the
activities are appropriate.
In the event that Trident discovers an injured or dead marine
mammal and the lead PSO 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), Trident would report the incident
to the Chief of the Permits and Conservation Division, Office of
Protected Resources, NMFS, and the NMFS Alaska Stranding Hotline and/or
by email to the Alaska Regional Stranding Coordinator, within 24 hours
of the discovery. Trident would provide photographs, video footage (if
available), or other documentation of the stranded animal sighting to
NMFS and the Marine Mammal Stranding Network
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 impacts or responses (e.g., intensity, duration),
the context of any impacts or responses (e.g., critical reproductive
time or location, foraging impacts affecting energetics), 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' 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 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, the discussion of our analysis applies to all
the species listed in table 2, given that the anticipated effects of
this activity on these different marine mammal stocks are expected to
be similar. There is little information about the nature or severity of
the impacts, or the size, status, or structure of any of these species
or stocks that would lead to a different analysis for this activity.
Pile driving and removal activities associated with the project as
outlined previously, have the potential to disturb or displace marine
mammals. Specifically, the specified activities may result in take, in
the form of Level B harassment from underwater sounds generated from
pile driving and removal. Level A harassment is extremely unlikely
given the small size of the Level A harassment isopleths and the
required mitigation measures designed to minimize the possibility of
injury to marine mammals (see Proposed Mitigation section). No
mortality is anticipated given the nature of the activity. Pile
installation and removal activities are likely to result in the Level B
harassment of marine mammals that move into the ensonified zone,
primarily in the form of disturbance or displacement of marine mammals.
Take would occur within a limited, confined area of each stock's range.
Level B harassment would be reduced to the level of least practicable
adverse impact through use of mitigation measures described herein.
Further, the amount of take authorized is small when compared to stock
abundance.
Based on reports in the literature as well as monitoring from other
similar
[[Page 88891]]
activities, behavioral disturbance (i.e., level B harassment) would
likely be limited to reactions such as increased swimming speeds,
increased surfacing time, or decreased foraging (if such activity were
occurring) (e.g., Thorson and Reyff, 2006; HDR, Inc. 2012; Lerma, 2014;
ABR, 2016). Most likely for pile driving, individuals would simply move
away from the sound source and be temporarily displaced from the areas
of pile driving, although even this reaction has been observed
primarily only in association with impact pile driving. The pile
driving activities analyzed here are similar to, or less impactful
than, numerous other construction activities conducted in Alaska, which
have taken place with no observed severe responses of any individuals
or known long-term adverse consequences. Level B harassment would be
reduced to the level of least practicable adverse impact through use of
mitigation measures described herein and, if sound produced by project
activities is sufficiently disturbing, animals are likely to simply
avoid the area while the activity is occurring. While vibratory driving
associated with the proposed project may produce sound at distances of
many kilometers from the project site, thus overlapping with some
likely less-disturbed habitat, the project site itself is located in a
busy harbor and the majority of sound fields produced by the specified
activities are close to the harbor. Animals disturbed by project sound
would be expected to avoid the area and use nearby higher-quality
habitats.
The project also is not expected to have significant adverse
effects on affected marine mammals' habitat. The project activities
would not modify existing marine mammal habitat for a significant
amount of time. The activities may cause some fish or invertebrates to
leave the area of disturbance, thus temporarily impacting marine
mammals' foraging opportunities in a limited portion of the foraging
range; but, because of the short duration of the activities, the
relatively small area of the habitat that may be affected, and the
availability of nearby habitat of similar or higher value, the impacts
to marine mammal habitat are not expected to cause significant or long-
term negative consequences.
The waters around Kodiak Island are part of the Alaska humpback
whale feeding BIA (Ferguson et al., 2015). Humpback whales are present
around Kodiak, although the majority of sightings have occurred outside
of Near Island Channel. The area of the BIA that may be affected by the
proposed project is small relative to the overall area of the BIA. The
humpback whale feeding BIA is active between May and November while the
proposed project is scheduled to occur between March and June,
resulting in only 2 months of overlap. Additionally, pile driving
associated with the project is expected to take only 55 days, further
reducing the temporal overlap with the BIA. Therefore, the proposed
project is not expected to have significant adverse effects on the
foraging of Alaska humpback whale. No areas of specific biological
importance (e.g., ESA critical habitat, other BIAs, or other areas) for
any other species are known to co-occur with the project area.
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 any of the species
or stocks through effects on annual rates of recruitment or survival:
<bullet> No serious injury, mortality, or Level A harassment is
anticipated or authorized;
<bullet> The anticipated incidents of Level B harassment would
consist of, at worst, temporary modifications in behavior that would
not result in fitness impacts to individuals;
<bullet> The ensonifed areas from the project are very small
relative to the overall habitat ranges of all species and stocks;
<bullet> The lack of anticipated significant or long-term negative
effects to marine mammal habitat or any other areas of known biological
importance; and
<bullet> The proposed mitigation measures are expected to reduce
the effects of the specified activity to the level of least practicable
adverse impact.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the proposed monitoring and
mitigation measures, NMFS preliminarily finds that the total marine
mammal take from the proposed activity will have a negligible impact on
all affected marine mammal species or stocks.
Small Numbers
As noted previously, only take of small numbers of marine mammals
may be authorized under sections 101(a)(5)(A) and (D) of the MMPA for
specified activities other than military readiness activities. The MMPA
does not define small numbers and so, in practice, where estimated
numbers are available, NMFS compares the number of individuals taken to
the most appropriate estimation of abundance of the relevant species or
stock in our determination of whether an authorization is limited to
small numbers of marine mammals. When the predicted number of
individuals to be taken is fewer than one-third of the species or stock
abundance, the take is considered to be of small numbers. Additionally,
other qualitative factors may be considered in the analysis, such as
the temporal or spatial scale of the activities.
Table 8 demonstrates the number of animals that could be exposed to
received noise levels that could cause Level B harassment for the
proposed work in Kodiak, Alaska. Our analysis shows that less than 14
percent of each affected stock could be taken by harassment. The
numbers of animals proposed to be taken for these stocks would be
considered small relative to the relevant stock's abundances, even if
each estimated taking occurred to a new individual--an extremely
unlikely scenario.
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 would be taken relative to the population
size of the affected species or stocks.
Unmitigable Adverse Impact Analysis and Determination
In order to issue an IHA, NMFS must find that the specified
activity will not have an ``unmitigable adverse impact'' on the
subsistence uses of the affected marine mammal species or stocks by
Alaskan Natives. NMFS has defined ``unmitigable adverse impact'' in 50
CFR 216.103 as an impact resulting from the specified activity: (1)
That is likely to reduce the availability of the species to a level
insufficient for a harvest to meet subsistence needs by: (i) Causing
the marine mammals to abandon or avoid hunting areas; (ii) Directly
displacing subsistence users; or (iii) Placing physical barriers
between the marine mammals and the subsistence hunters; and (2) That
cannot be sufficiently mitigated by other measures to increase the
availability of marine mammals to allow subsistence needs to be met.
In the Kodiak area sea lions and harbor seals are available for
subsistence harvest under the MMPA. Limited subsistence harvests of
marine mammals outside of Near Island Channel has occurred in the past,
with the most recent recorded/documented harvests of marine mammals in
Kodiak in 2011. The proposed activity will take place in Near Island
Channel, and no activities overlap with current subsistence hunting
areas; therefore,
[[Page 88892]]
there are no relevant subsistence uses of marine mammals adversely
impacted by this action. The proposed project is not likely to
adversely impact the availability of any marine mammal species or
stocks that are commonly used for subsistence purposes or to impact
subsistence harvest of marine mammals in the region.
Based on the description of the specified activity, the measures
described to minimize adverse effects on the availability of marine
mammals for subsistence purposes, and the proposed mitigation and
monitoring measures, NMFS has preliminarily determined that there will
not be an unmitigable adverse impact on subsistence uses from Trident's
proposed activities.
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 whenever we propose to authorize take for
endangered or threatened species, in this case with the Alaska Regional
Office.
NMFS is proposing to authorize take of western DPS of Steller sea
lions, which are listed under the ESA. The Permits and Conservation
Division has requested initiation of section 7 consultation with the
Alaska Regional Office for the issuance of this IHA. NMFS will conclude
the ESA consultation prior to reaching a determination regarding the
proposed issuance of the authorization.
Proposed Authorization
As a result of these preliminary determinations, NMFS proposes to
issue an IHA to Trident for conducting Bunkhouse Dock replacement
project in Kodiak, Alaska between March 1, 2024 and February 29, 2025,
provided the previously mentioned mitigation, monitoring, and reporting
requirements are incorporated. A draft of the proposed IHA can be found
at: <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities">https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities</a>.
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
construction project. We also request comment on the potential renewal
of this proposed IHA as described in the paragraph below. Please
include with your comments any supporting data or literature citations
to help inform decisions on the request for this IHA or a subsequent
renewal IHA.
On a case-by-case basis, NMFS may issue a one-time, 1-year renewal
IHA following notice to the public providing an additional 15 days for
public comments when (1) up to another year of identical or nearly
identical activities as described in the Description of Proposed
Activity section of this notice is planned or (2) the activities as
described in the Description of Proposed Activity section of this
notice would not be completed by the time the IHA expires and a renewal
would allow for completion of the activities beyond that described in
the Dates and Duration section of this notice, provided all of the
following conditions are met:
<bullet> A request for renewal is received no later than 60 days
prior to the needed renewal IHA effective date (recognizing that the
renewal IHA expiration date cannot extend beyond 1 year from expiration
of the initial IHA).
<bullet> The request for renewal must include the following:
(1) An explanation that the activities to be conducted under the
requested renewal IHA are identical to the activities analyzed under
the initial IHA, are a subset of the activities, or include changes so
minor (e.g., reduction in pile size) that the changes do not affect the
previous analyses, mitigation and monitoring requirements, or take
estimates (with the exception of reducing the type or amount of take).
(2) A preliminary monitoring report showing the results of the
required monitoring to date and an explanation showing that the
monitoring results do not indicate impacts of a scale or nature not
previously analyzed or authorized.
Upon review of the request for renewal, the status of the affected
species or stocks, and any other pertinent information, NMFS determines
that there are no more than minor changes in the activities, the
mitigation and monitoring measures will remain the same and
appropriate, and the findings in the initial IHA remain valid.
Dated: December 19, 2023.
Kimberly Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2023-28336 Filed 12-22-23; 8:45 am]
BILLING CODE 3510-22-P
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</html>Indexed from Federal Register on December 26, 2023.
This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.