Notice2023-02997
Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to the Whittier Head of the Bay Cruise Dock Project in Whittier, Alaska
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
February 13, 2023
Issuing agencies
Commerce DepartmentNational Oceanic and Atmospheric Administration
Abstract
NMFS has received a request from Turnagain Marine Construction (TMC) for authorization to take marine mammals incidental to the cruise dock construction project in Whittier, 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 29 (Monday, February 13, 2023)</title>
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[Federal Register Volume 88, Number 29 (Monday, February 13, 2023)]
[Notices]
[Pages 9227-9249]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2023-02997]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[RTID 0648-XC705]
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to the Whittier Head of the Bay Cruise
Dock Project in Whittier, 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 Turnagain Marine Construction
(TMC) for authorization to take marine mammals incidental to the cruise
dock construction project in Whittier, 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 March
15, 2023.
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#377e6367195f56455b56545f5245775958565619505841"><span class="__cf_email__" data-cfemail="0a435e5a24626b78666b69626f784a64656b6b246d657c">[email protected]</span></a>.
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="http://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act">www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act</a> without change. All personal identifying
information (e.g., name, address) voluntarily submitted by the
commenter may be publicly accessible. Do not submit confidential
business information or otherwise sensitive or protected information.
FOR FURTHER INFORMATION CONTACT: Jenna Harlacher, Office of Protected
Resources, NMFS, (301) 427-8401. Electronic copies of the application
and supporting documents, as well as a list of the references cited in
this document, may be obtained online at: <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities#active-authorizations">https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities#active-authorizations</a>. In
case of problems accessing these documents, please call the contact
listed above.
SUPPLEMENTARY INFORMATION:
Background
The MMPA prohibits the ``take'' of marine mammals, with certain
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to
allow, upon request, the incidental, but not intentional, taking of
small numbers of marine mammals by U.S. citizens who engage in a
specified activity (other than commercial fishing) within a specified
geographical region if certain findings are made and either regulations
are 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
[[Page 9228]]
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 NOAA Administrative Order 216-
6A, which do not individually or cumulatively have the potential for
significant impacts on the quality of the human environment and for
which we have not identified any extraordinary circumstances that would
preclude this categorical exclusion. Accordingly, NMFS has
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 September 16, 2022, NMFS received a request from TMC for an IHA
to take marine mammals incidental to the construction of the cruise
ship dock in Whittier, Alaska. Following NMFS' review of the
application, TMC provided further information on October 26, 2022, a
revised application on January 9, 2023, and the application was deemed
adequate and complete on January 10, 2023. Subsequently, TMC submitted
an additional update to its application on February 3, 2023. TMC's
request is for take of five species of marine mammals by Level B
harassment and, for a subset of two species, Level A harassment.
Neither TMC nor NMFS expect serious injury or mortality to result from
this activity and, therefore, an IHA is appropriate.
Description of Proposed Activity
Overview
TMC proposes to construct the Whittier Head of the Bay cruise ship
dock project in the Passage Canal in Whittier, Alaska. The proposed
project will cover a 12-month window during which approximately 129
days of pile-installation and -removal activity will occur. This
project involves installation and removal of 72 36-inch (in) (0.91
meter (m)) temporary steel pile guides and installation of 36 36-in, 16
42-in (1.1-m), and 20 48-in (1.2-m) permanent steel piles. Three
different installation methods will be used including vibratory
installation of piles into dense material, impact pile driving to drive
piling to tip elevation, and the Down-the-Hole (DTH) hammer to drill
pile into the bedrock. TMC will deploy a bubble curtain to the 60-foot
(ft.) (18.3-m) isobath. This would be used during all activities that
fall below the 60-ft. isobath. Sounds resulting from pile installation,
removal, and drilling may result in the incidental take of marine
mammals by Level A and Level B harassment in the form of auditory
injury or behavioral harassment.
Dates and Duration
The proposed IHA would be effective from April 1, 2023 through
March 31, 2024. The total expected work duration would be approximately
321 hours over 129 nonconsecutive days (an estimated 45 days of DTH, 59
days of vibratory pile installation, and 24.5 days of impact pile
driving). An estimated 156 hours over 58.5 days would use a bubble
curtain, and 165 hours over 70 days would be unattenuated. The
construction timeline takes into account the mobilization of materials
and potential delays due to delayed material deliveries, equipment
maintenance, inclement weather, and shutdowns. TMC plans to conduct all
work during daylight hours.
Specific Geographic Region
The proposed activity will occur in the head of Passage Canal, a
bay of Prince William Sound in South Central Alaska in Whittier, Alaska
(Figure 1-2). This proposed cruise ship dock would be approximately one
kilometer (0.75 miles) northwest of downtown Whittier. Passage Canal is
an approximately 12-mile-long (19.3 kilometer (km)) fjord that measures
less than 2 miles (3.2-km) across from shore to shore at its widest
point and reaches depths over 1,000-ft (304.8-m) at its entrance near
Decision Point and Blackstone Bay. Depths at the head of Passage Canal
are shallower, approximately 100 to 200-ft (30.48 to 60.96-m).
[[Page 9229]]
[GRAPHIC] [TIFF OMITTED] TN13FE23.001
Detailed Description of the Specified Activity
TMC proposes to install and remove 72 steel piles to guide the 72
permanent piles into place to support the cruise ship berth and
floating dock. The piles would be installed using three methods over
129 days, which incorporated buffer days to account for unforeseen
interruptions. These methods include vibratory pile installation and
removal, impact pile driving, and DTH drilling (see Table 1).
Pile templates would be constructed using temporary pilings
vibrated into position. Three or four temporary 36-in diameter pilings
may be needed for each template. Most temporary piles would be vibrated
into place; however, up to 36 of these may need to make use of a DTH
drill in locations where the bedrock is shallow. For each 36-in
temporary pile, an estimated 2 cubic yards (CY) (1.53 cubic meter) of
drill cuttings would be produced. Using the templates as guides to
position the permanent piling, the piling would be vibrated into dense
material. The piling would then be driven to tip elevation using an
impact hammer. Once the piles achieve the tip elevation, a DTH hammer
would be placed inside the piling and a shaft would be drilled into the
bedrock. The rock shaft would be filled with concrete to anchor the
pile to the bedrock. The 36 permanent 36-in diameter steel piles
supporting the approach trestle would be vibrated to at least 24 feet
(7.31-m) below the mudline. If the soil depth is less than 24 feet, the
piles would then be drilled at least 10 feet (3.05-m) deep into bedrock
with a DTH hammer and bit. For each 36-in permanent pile, an estimated
10 CY (7.65 cubic meter) of drill cuttings would be produced. The 16
permanent 42-in diameter and 20 permanent 48-in diameter steel piles
would be vibrated through the soil layer to bedrock to support other
dock components. A 38-in diameter shaft would be drilled through the
42- and 48-in diameter into the bedrock with the DTH hammer and bit,
and then filled with concrete to a depth of at least 25 feet (7.62-m)
to anchor the piles.
TMC divides the work into two areas by depth; activities occurring
within the 60-ft. isobath or shallower and, those occurring in depths
greater than the 60-ft. isobath. The 36 36-in permanent piles
supporting the approach trestle and the 36 36-inch temporary piles used
as template guides for them would fall within the 60-ft. isobath. The
16 42-inch and 20 48-inch for the mooring trestle and dolphins (and the
36 36-inch temporary piles used as template guides for these) would
fall within waters deeper than the 60-ft. isobath. A bubble curtain
would be deployed at a depth of 60 feet (18.3-m) and would be used
during all activities that fall within the 60-ft. isobath.
Additional actions occurring under the proposed action that are not
anticipated to generate in-water noise resulting in marine mammal
harassment include vessels to support construction and out of water
dock components. NMFS does not expect, that these ancillary activities
will harm or harass marine mammals and no incidental takes are expected
as a result of these activities. Therefore, these activities are not
discussed further in this document.
Table 1--Pile Installation Methods and Durations
----------------------------------------------------------------------------------------------------------------
Number of Duration/impacts per Piles drive/
Pile size, method piles pile day Estimated days
----------------------------------------------------------------------------------------------------------------
36-in steel pile, Vibratory 72 10 min.................. 4 18
Installation (temporary).
36-in steel pile, Vibratory Removal 72 10 min.................. 4 18
(temporary).
36-in steel pile, Vibratory 36 15 min.................. 4 9
Installation (permanent).
42-in steel pile, Vibratory 16 15 min.................. 4 4
Installation.
48-in steel pile, Vibratory 20 15 min.................. 2 10
Installation.
[[Page 9230]]
36-in steel pile, Impact Installation 36 1800 strikes............ 4 9
(permanent).
42-in steel pile, Impact Installation. 16 2400 strikes............ 3 5.5
48-in steel pile, Impact Installation. 20 2400 strikes............ 2 10
36-in steel pile, DTH Installation 36 60 min.................. 4 9
(temporary).
36-in steel pile, DTH Installation 36 150 min................. 2 18
(permanent).
42-in steel pile, DTH Installation.... 16 150 min................. 2 8
48-in steel pile, DTH Installation.... 20 150 min................. 2 10
----------------------------------------------------------------------------------------------------------------
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, incorporated here by reference, instead of
reprinting the information. Additional information regarding population
trends and threats may be found in NMFS' Stock Assessment Reports
(SARs; <a href="http://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments">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 expected to occur, 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 stocks managed under the MMPA in this region
are assessed in NMFS' U.S. 2021 SARs (e.g., Muto et al., 2021) and the
draft 2022 SARs (e.g., Young et al., 2022). All values presented in
Table 2 are the most recent available at the time of publication and
are available online at: <a href="http://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments">www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments</a>).
Table 2--Species Likely Impacted by the Specified Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
ESA/MMPA status; Stock abundance (CV,
Common name Scientific name Stock strategic (Y/N) Nmin, most recent PBR Annual M/
\1\ abundance survey) \2\ SI \3\
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Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Balaenopteridae (rorquals):
Humpback whale.................. Megaptera novaeanglinae Central North Pacific -,D,Y 10,103 (0.3, 7,890, 83 26
Stock. 2006).
Western North Pacific.. E,D,Y 1,107 (0.3, 865, 2006) 3 2.8
California/Oregon/ T,D,Y 4,973 (0.05, 4,776, 28.7 48.3
Washington. 2018).
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Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Family Delphinidae:
Killer whale.................... Orca orcinus........... Alaska Resident........ -,-,N 1,920 (N/A, 1,920, 19 1.3
2019).
Gulf of Alaska/Aleutian -,-,N 587 (N/A, 587, 2012).. 5.9 0.8
Islands/Bering Sea
Transient.
AT1 Transient.......... -,D,Y 7 (N/A, 7, 2019)...... 0.01 1
Family Phocoenidae (porpoises):
Dall's porpoise \4\............. Phocoenoides dalli..... Alaska Stock........... -,-,N 15,432 (0.097, 13, 131 37
110, 2021).
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Order Carnivora--Superfamily Pinnipedia
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Family Otariidae (eared seals and
sea lions):
Steller sea lion................ Eumetopias jubatus..... Western Stock.......... E,D,Y 52,932 (N/A, 52,932, 318 254
2019).
Family Phocidae (earless seals):
[[Page 9231]]
Harbor seal..................... Phoca vituline Clarence Strait Stock.. -,-,N 27,659 (N/A, 24,854, 746 40
richardii. 2015).
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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">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports</a> CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\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\ Previous abundance estimates covering the entire stock's range are no longer considered reliable and the current estimates presented in the SARs and
reported here only cover a portion of the stock's range. Therefore, the calculated Nmin and PBR is based on the 2015 survey of only a small portion of
the stock's range. PBR is considered to be biased low since it is based on the whole stock whereas the estimate of mortality and serious injury is for
the entire stock's range.
On January 24, 2023, NMFS published the draft 2022 SARs (<a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports</a>-region). The Alaska and Pacific Ocean SARs
include a proposed update to the humpback whale stock structure. The
new structure, if finalized, would modify the MMPA-designated stocks to
align more closely with the ESA-designated DPSs. Please refer to the
draft 2022 Alaska and Pacific Ocean SARs for additional information.
NMFS Office of Protected Resources, Permits and Conservation
Division has generally considered peer-reviewed data in draft SARs
(relative to data provided in the most recent final SARs), when
available, as the best available science, and has done so here for all
species and stocks, with the exception of a new proposal to revise
humpback whale stock structure. Given that the proposed changes to the
humpback whale stock structure involve application of NMFS's Guidance
for Assessing Marine Mammals Stocks and could be revised following
consideration of public comments, it is more appropriate to conduct our
analysis in this proposed authorization based on the status quo stock
structure identified in the most recent final SARs (2021; Muto et al.,
2022).
As indicated above, all five 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, and we have proposed
authorizing it. All species that could potentially occur in the
proposed survey areas are included in Table 5 of the IHA application.
While some species have been reported in or near the area, it is very
rare, and the temporal and/or spatial occurrence of these species is
more likely outside of the Passage Canal and outside of the harassment
zones. Therefore, given this information take is not expected to occur
and they are not discussed further beyond the explanation provided
here.
In addition, the northern sea otter (Enhydra lutris kenyoni) may be
found in the Passage Canal. However, northern sea otters are managed by
the U.S. Fish and Wildlife Service and are not considered further in
this document.
Humpback Whale
The humpback whale is found worldwide in all oceans. Prior to 2016,
humpback whales were listed under the ESA as an endangered species
worldwide. Following a 2015 global status review (Bettridge et al.,
2015), NMFS established 14 Distinct Population Segments (DPS) with
different listing statuses (81 FR 62259; September 8, 2016) pursuant to
the ESA. Humpback whales found in the project area are predominantly
from the three DPSs that are present in Alaska.
Whales from the Western North Pacific (WNP), Mexico, and Hawaii
DPSs overlap on feeding grounds off Alaska and are not visually
distinguishable. Members of different DPSs are known to intermix on
feeding grounds; therefore, all waters off the coast of Alaska should
be considered to have ESA-listed humpback whales. Based on an analysis
of migration between winter mating/calving areas and summer feeding
areas using photo-identification, Wade (2021) concluded that the
humpback whales feeding in Alaskan waters belong primarily to the
recovered Hawaii DPS (89 percent), with small contributions from the
threatened Mexico DPS (11 percent) and the endangered WNP DPS (0.4
percent; rounded to 1 percent in NMFS 2021a).
The DPSs of humpback whales that were identified through the ESA
listing process do not equate to the existing MMPA stocks. The updated
stock delineations for humpback whales under the MMPA are currently out
for public review in the draft 2022 SAR's, as mentioned above. Until
this review is complete, NMFS considers humpback whales in Southeast
Alaska to be part of the Central North Pacific stock (Muto et al.,
2021).
Humpback whales are found throughout Southcentral Alaska in a
variety of marine environments, including open-ocean, near-shore
waters, and areas within strong tidal currents (Dahlheim et al., 2009).
Humpback whales generally arrive in Southeast Alaska in March and
return to their wintering grounds in November. Some humpback whales
depart late or arrive early to feeding grounds, and therefore the
species can occur in the Southeast Alaska region year-round (Straley,
1990, Straley et al., 2018). Across the region, there have been no
recent estimates of humpback whale density.
NMFS identified a portion of Prince William Sound as a Biologically
Important Area (BIA) for humpback whales for feeding during the months
of September through December; however, the proposed action area is
northwest of the boundaries of the BIA (NMFS 2022c). BIAs are spatial
and temporal boundaries identified for certain marine mammal species
where populations are known to concentrate for specific behaviors such
as migration, feeding, or breeding. This BIA was identified due to
boat-based surveys that observed high number of humpback whales feeding
(mainly on Pacific herring) in the area (Ferguson et al., 2015).
Humpback whale BIAs helped to inform the critical habitat designation
finalized by NMFS in 2021 (86 FR 21082, April 21, 2021). Much of Prince
William Sound is also within humpback whale critical habitat, and
material and equipment barges' routes would transit through critical
habitat on the way to the project site. However, the proposed project
is approximately 17 km west of the boundaries of the critical habitat,
and
[[Page 9232]]
the ensonified action area extends through Passage Canal, but ends
about 3.5 kilometers west of the critical habitat boundary.
In Prince William Sound and Passage Canal, humpback whales are
traditionally observed during seasons of high prey concentration, May
through September (Witteveen et al., 2011; SolsticeAK 2022). However,
feeding humpback whales' presence in the Gulf of Alaska has also been
correlated closely with peak herring abundance, which occurs in the
late fall and early winter. It has been suggested that some whales
remain longer in northern waters to maximize food consumption prior to
migrating south to breeding grounds in the winter, and a few may skip
migration altogether (Straley et al., 2018). Therefore, humpbacks may
be present year-round in Prince William Sound, but are less common
during the late winter and early spring.
While sightings of humpbacks are fairly common in Prince William
Sound, they are less common in Passage Canal (SolsticeAK 2022). No
humpback whales were observed within Passage Canal during the Whittier
Ferry Terminal Modification Project in April 2020 (Leonard and Wisdom
2020).
Dall's Porpoise
All Dall's porpoises in Alaska are members of the Alaska stock.
This species can be found in offshore, inshore, and nearshore habitats.
Dall's porpoises are widely distributed across the North Pacific Ocean
and are one of the most common cetaceans in the Gulf of Alaska (Rone et
al., 2017). Surveys conducted in the Gulf of Alaska from 2009 to 2015
indicate that Dall's porpoises inhabit all strata on the continental
shelf, slope, and pelagic waters with the greatest densities occurring
in deeper inshore and slope habitats (Rone et al., 2017).
From data collected during surveys conducted from 2007 to 2015,
Dall's porpoise presence in Prince William Sound varied based on
season. They were most dispersed throughout Prince William Sound in the
summer months but tended towards deeper waters in the middle of the
Sound, away from shorelines. In the fall and winter, they were more
often observed in the periphery of Prince William Sound with
concentrations in bay areas, likely following herring shoals towards
their overwintering areas. Their distribution was most concentrated in
the spring, with one major activity center in eastern Prince William
Sound. These porpoises were not typically found in shallow habitats or
confined fjords like that of Passage Canal, preferring open water
escape routes where they are able to use quick swimming techniques to
evade predators such as killer whales (Moran et al., 2018).
Dall's porpoises are frequently observed near the entrance of
Passage Canal but not often seen far down the canal near Whittier
(DOT&PF 2019). Correspondence with local tour boat captains confirmed
there are occasional sightings of Dall's porpoise in Passage Canal, but
they are more often seen farther out towards Prince William Sound in
Well's Passage (SolsticeAK 2022). The Whittier Ferry Terminal
Modification Project Marine Mammal Monitoring Report indicated that
there was one sighting of a group of six Dall's porpoises in Passage
Canal during construction work in April 2020 (Leonard and Wisdom 2020).
Killer Whale
Killer whales occur along the entire Alaska coast, in British
Columbia and Washington inland waterways, and along the outer coasts of
Washington, Oregon, and California (NMFS, 2016). The three stocks that
are most likely to occur in Prince William Sound are the southern
Alaska Resident stock, Gulf of Alaska/Aleutian Islands/Bering Sea
Transient stock, and the AT1 Transient stock (Muto et al., 2022).
There are three distinct ecotypes, or forms, of killer whales
recognized: Resident, Transient, and Offshore. The three ecotypes
differ morphologically, ecologically, behaviorally, and genetically.
Both residents and transients are common in a variety of habitats and
all major waterways, including protected bays and inlets. There does
not appear to be strong seasonal variation in abundance or distribution
of killer whales, but there was substantial variability between years
(Dahlheim et al., 2009). Spatial distribution has been shown to vary
among the different ecotypes, with resident and, to a lesser extent,
transient killer whales more commonly observed along the continental
shelf, and offshore killer whales more commonly observed in pelagic
waters (Rice et al., 2017).
In the Gulf of Alaska, the offshore killer whale ecotype is found
in pelagic waters off the Aleutian Islands to California and mainly
prey on sharks; the resident ecotype (southern Alaska residents) ranges
from Kodiak Island to Southeast Alaska and prefer to eat fish; and two
different transient populations (Gulf of Alaska transients and AT1
transients) prefer marine mammals are most often found near the
Hinchinbrook Entrance and Montague Strait (Myers et al., 2021). A
tagging study focused on resident killer whale movements in Prince
William Sound found that killer whales' favored use areas were highly-
seasonal and pod specific, likely timed with seasonal salmon returns to
spawning streams (Olsen et al., 2018).
With the exception of the AT1 Transient stock, the populations that
are known to occur in Prince William Sound are not strategic or
depleted under the MMPA. Long-term studies of pods belonging to the
southern Alaska resident stock in the Gulf of Alaska indicate these
populations are increasing at an estimated growth rate of approximately
3.4 percent (Matkin et al., 2014). However, both resident and transient
killer whales were significantly impacted by the 1989 Exxon Valdez Oil
spill. Prior to the spill, the resident AB pod consisted of 36 members
and from 1989 to 1990, 14 whales disappeared from the pod. The AB pod
is considered recovering; however, due to slow reproduction rates only
28 individuals were observed in 2005 (Exxon Valdez Oil Spill Trustee
Council 2021). The AT1 Transient stock also experienced high mortality
following the oil spill, as 11 of the original 22 individuals
disappeared between 1989 and 1992. The AT1 stock currently numbers only
seven individuals (Muto et al., 2021).
Results from the Olsen et al., (2018) satellite tagging surveys in
Prince William Sound from 2006 to 2014 revealed several core use areas
for resident killer whales based on pod and season. Most resident pods
primarily concentrated at the southern end of Prince William Sound in
Hinchinbrook Entrance during the summer and Montague Strait in the late
summer and fall. A few of the pods were observed making trips to deeper
glacial fjords including Passage Canal, but these areas did not appear
to be an important focus area for the pods. The AD16 pod (estimated 9
animals) and AK pod (estimated 19 animals) were the most frequently
observed in the northern glacial fjords of the sound (Muto et al.,
2022; Olsen et al., 2018).
Additionally, a 27-year photo identification study in Prince
William Sound and Kenai Fjords surveyed both populations of transient
killer whales. The study found that the AT1 transients had higher site
fidelity to the area, while the Gulf of Alaska transients had a higher
exchange of individuals (Matkin et al., 2012). Resighting data
indicated that the AT1 population are resident to the area and the Gulf
of Alaska transients are part of a larger population with a more
extensive range. Throughout the study, survival estimates for both
populations was generally high, but there was significant
[[Page 9233]]
population reduction in the AT1 transient after the Exxon Valdez oil
spill (Matkin et al., 2012). There was no detectable decline in the
larger Gulf of Alaska transient population after the oil spill (Matkin
et al., 2012).
Consultation with marine wildlife tour operators confirmed that
killer whales are often observed in Prince William Sound, but less
commonly seen in Passage Canal (SolsticeAK 2022). There are prey
resources (marine mammals, salmon, etc.) present that may draw killer
whales to the area, particularly during salmon runs from June through
October, but concentration of prey is not likely large enough to keep
killer whales in the area for long. During the Whittier Ferry Terminal
Modification Project in April 2020, there were no observations of
killer whales in the action area (Leonard and Wisdom 2020).
Harbor Seal
Harbor seals inhabit coastal and estuarine waters off Alaska and
are one of the most common marine mammals in Alaska. They haul out on
rocks, reefs, beaches, and drifting glacial ice. They are opportunistic
feeders and often adjust their distribution to take advantage of
locally and seasonally abundant prey, feeding in marine, estuarine, and
occasionally fresh waters (Womble et al., 2009, Allen and Angliss,
2015). Harbor seals are generally non-migratory and, with local
movements associated with such factors as tide, weather, season, food
availability and reproduction. They deviate from other pinniped species
in that pupping may occur on a wide variety of haul-out sites rather
than particular major rookeries (ADF&G 2022).
Distribution of the Prince William Sound stock, the only stock
considered in this application, range from Elizabeth Island off the
southwest tip of the Kenai Peninsula to Cape Fairweather, including
Prince William Sound, the Copper River Delta, Icy Bay, and Yakutat Bay
(Muto et al., 2022). The Prince William Sound stock of harbor seals are
commonly sighted residents and can occur on any given day in the action
area, although they tend to be more abundant during the fall months
(Womble and Gende 2013).
Communication with Whittier tour operators indicated that harbor
seals are often seen in Passage Canal, but generally do not gather near
Whittier in large numbers (SolsticeAK 2022). They sometimes haul out at
the Whittier Public Boat Harbor around 1,500 meters away (DOT&PF 2019).
The Marine Mammal Monitoring Report from the Whittier Ferry Terminal
Modification reported 10 sightings of 13 harbor seals during the April
2020 construction period, which agrees with the tour operators'
accounts (commonly seen, generally individual animals rather than
groups) (Leonard and Wisdom 2020).
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 2022f).
Steller sea lions are distributed throughout Southcentral Alaska,
with patterns loosely correlated to aggregations of spawning and
migrating prey species (Sinclair and Zeppelin 2002; Sinclair et al.,
2013). Haulout sites in Southcentral Alaska, at and west of Cape
Suckling, were documented through aerial surveys (Fritz et al., 2013).
Although there are no documented haulouts or rookeries within Passage
Canal, a small number of Steller sea lions have been reported hauling
out year-round on a mooring buoy in Shotgun Cove (SolsticeAK 2022;
DOT&PF 2019).
Steller sea lions occur year-round in the program action area.
Steller sea lions are drawn to fish processing plants and high forage
value areas such as anadromous streams. Passage Canal has several
anadromous streams that support salmon species and one fish processing
plant with an Alaska Department of Environmental Conservation (ADEC)
permitted outfall that also attracts Steller sea lions (ADF&G 2022a).
There were 9 Steller sea lion groups (representing about 27
individuals) sighted during marine mammal monitoring of the Whittier
Ferry Terminal Modification Project in April 2020. Groups ranged from
one to seven animals. Steller sea lions were most often observed
floating and/or swimming at the surface. Sightings occurred over a
period of 6 days and approximately 86 hours of monitoring time (Leonard
and Wisdom 2020).
Critical habitat for Steller sea lions was designated by NMFS in
1993 based on the following essential physical and biological habitat
features: terrestrial habitat (including rookeries and haulouts
important for rest, reproduction, growth, social interactions) and
aquatic habitat (including nearshore waters around rookeries and
haulouts, free passage for migration, prey resources, and foraging
habitats) (58 FR 45269).
The nearest rookery is Seal Rocks located in the Hinchinbrook
Entrance between Hinchinbrook and Montague Islands, 124 kilometers (67
nautical miles) southeast of the proposed berth site. The nearest major
haulouts are Perry, approximately 44 kilometers (24 nautical miles)
southeast of the proposed berth site and Dutch Group, approximately 52
kilometers (28 nautical miles) east (Alaska Fisheries Science Center
2022). Since the ensonified action area encompasses most of Passage
Canal, it would intersect Steller sea lion designated critical habitat.
Additionally, since most of Prince William Sound is within Steller sea
lion critical habitat, material and equipment barges' routes would
transit through critical habitat on the way to the project site.
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
[[Page 9234]]
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]
------------------------------------------------------------------------
Generalized hearing
Hearing group range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen whales).... 7 Hz to 35 kHz.
Mid-frequency (MF) cetaceans (dolphins, toothed 150 Hz to 160 kHz.
whales, beaked whales, bottlenose whales).
High-frequency (HF) cetaceans (true porpoises, 275 Hz to 160 kHz.
Kogia, river dolphins, Cephalorhynchid,
Lagenorhynchus cruciger & L. australis).
Phocid pinnipeds (PW) (underwater) (true seals). 50 Hz to 86 kHz.
Otariid pinnipeds (OW) (underwater) (sea lions 60 Hz to 39 kHz.
and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
composite (i.e., all species within the group), where individual
species' hearing ranges are typically not as broad. Generalized
hearing range chosen based on ~65 dB threshold from normalized
composite audiogram, with the exception for lower limits for LF
cetaceans (Southall et al. 2007) and PW pinniped (approximation).
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006; Kastelein et al., 2005; 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 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.
Acoustic effects on marine mammals during the specified activity
can occur from impact pile driving, vibratory driving, and DTH. The
effects of underwater noise from TMC's proposed activities have the
potential to result in Level A or Level B harassment of marine mammals
in the action area.
Description of Sound Source
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 10-20 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 removal, impact and vibratory pile driving, and
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 2018a). 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 2018a). 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 in Southall et al., 2007).
Three types of hammers would be used on this project: impact,
vibratory, and DTH. Impact hammers operate by repeatedly dropping a
heavy piston onto a pile to drive the pile into the substrate.
[[Page 9235]]
Sound generated by impact hammers is characterized by rapid rise times
and high peak levels, a potentially injurious combination (Hastings and
Popper, 2005). 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).
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 method contain both a continuous
non-impulsive component from the drilling action and an impulsive
component from the hammering effect. Therefore, we treat DTH systems as
both impulsive and non-impulsive sound source types simultaneously.
The likely or possible impacts of TMC's proposed activity on marine
mammals could involve both non-acoustic and acoustic stressors.
Potential non-acoustic stressors could result from the physical
presence of equipment and personnel; however, any impacts to marine
mammals are expected to be primarily acoustic in nature. Acoustic
stressors include effects of heavy equipment operation during pile
driving and drilling.
Acoustic Impacts
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 TMC's 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). 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.
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 decibels (dB). A TS can be
permanent or temporary. As described in NMFS (2018), 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 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 an 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).
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). Available data from
humans and other terrestrial mammals indicate that a 40 dB threshold
shift approximates PTS onset (see Ward et al., 1958, 1959; Ward 1960;
Kryter et al., 1966; Miller 1974; Ahroon et al., 1996; Henderson et
al., 2008). PTS levels 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)--TTS is 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 (see Southall et al., 2007), 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, 2002). As described in
Finneran (2015), marine mammal studies have shown the amount of TTS
increases with cumulative sound exposure level (SELcum) 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 SELcum, 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 a 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).
For cetaceans, published data on the onset of TTS are limited to the
captive bottlenose dolphin (Tursiops truncatus),
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beluga whale (Delphinapterus leucas), harbor porpoise, and Yangtze
finless porpoise (Neophocoena asiaeorientalis), and for pinnipeds in
water, measurements of TTS are limited to harbor seals, elephant seals
(Mirounga angustirostris), and California sea lions (Zalophus
californianus). These studies examine hearing thresholds measured in
marine mammals before and after exposure to intense sounds. 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, 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,
2019b). 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 (Finneran et al., 2010; Kastelein et al.,
2014; Kastelein et al., 2015a; Mooney et al., 2009). 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 the 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 echolocating
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).
Behavioral Harassment--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).
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; Weilgart 2007). Behavioral reactions can vary not only among
individuals but also within an individual, depending on previous
experience with a sound source, context, and numerous other factors
(Ellison et al., 2012), 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. Please see Appendices B-C of Southall et al.,
(2007) for a review of studies involving marine mammal behavioral
responses to sound.
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 would require 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.
Stress responses--An animal's perception of a threat may be
sufficient to trigger stress responses consisting of some combination
of behavioral responses, autonomic nervous system responses,
neuroendocrine responses, or immune responses (e.g., Seyle 1950; Moberg
2000). In many cases, an animal's first and sometimes most economical
(in terms of energetic costs) response is behavioral avoidance of the
potential stressor. Autonomic nervous system responses to stress
typically involve changes in heart rate, blood pressure, and
gastrointestinal activity. These responses have a relatively short
duration and may or may not have a significant long-term effect on an
animal's fitness.
Neuroendocrine stress responses often involve the hypothalamus-
pituitary-adrenal system. Virtually all neuroendocrine functions that
are affected by stress--including immune competence, reproduction,
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been
implicated in failed reproduction, altered metabolism, reduced immune
competence, and behavioral disturbance (e.g., Moberg 1987; Blecha
2000). Increases in the circulation of glucocorticoids are also equated
with stress (Romano et al., 2004).
The primary distinction between stress (which is adaptive and does
not normally place an animal at risk) and ``distress'' is the cost of
the response. During a stress response, an animal uses glycogen stores
that can be quickly replenished once the stress is alleviated. In such
circumstances, the cost of the stress response would not pose serious
[[Page 9237]]
fitness consequences. However, when an animal does not have sufficient
energy reserves to satisfy the energetic costs of a stress response,
energy resources must be diverted from other functions. This state of
distress will last until the animal replenishes its energetic reserves
sufficient to restore normal function.
Relationships between these physiological mechanisms, animal
behavior, and the costs of stress responses are well studied through
controlled experiments and for both laboratory and free-ranging animals
(e.g., Holberton et al., 1996; Hood et al., 1998; Jessop et al., 2003;
Lankford et al., 2005). Stress responses due to exposure to
anthropogenic sounds or other stressors and their effects on marine
mammals have also been reviewed (Fair and Becker 2000; Romano et al.,
2002b) and, more rarely, studied in wild populations (e.g., Romano et
al., 2002a). For example, Rolland et al., (2012) found that noise
reduction from reduced ship traffic in the Bay of Fundy was associated
with decreased stress in North Atlantic right whales. These and other
studies lead to a reasonable expectation that some marine mammals will
experience physiological stress responses upon exposure to acoustic
stressors and that it is possible that some of these would be
classified as ``distress.'' In addition, any animal experiencing TTS
would likely also experience stress responses (NRC, 2003), however
distress is an unlikely result of this project based on observations of
marine mammals during previous, similar projects in the area.
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). 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., pile driving, shipping, sonar,
seismic exploration) in origin. The ability of a noise source to mask
biologically important sounds depends on the characteristics of both
the noise source and the signal of interest (e.g., signal-to-noise
ratio, temporal variability, direction), in relation to each other and
to an animal's hearing abilities (e.g., sensitivity, frequency range,
critical ratios, frequency discrimination, directional discrimination,
age or TTS hearing loss), and existing ambient noise and propagation
conditions. Masking 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.
Airborne Acoustic Effects--Although pinnipeds are known to haul-out
regularly on man-made objects, we believe that incidents of take
resulting solely from airborne sound are unlikely due to the sheltered
proximity between the proposed project area and these haulout sites
(outside of Passage Canal). There is a possibility that an animal could
surface in-water, but with head out, within the area in which airborne
sound exceeds relevant thresholds and thereby be exposed to levels of
airborne sound that we associate with harassment, but any such
occurrence would likely be accounted for in our estimation of
incidental take from underwater sound. Therefore, authorization of
incidental take resulting from airborne sound for pinnipeds is not
warranted, and airborne sound is not discussed further here. Cetaceans
are not expected to be exposed to airborne sounds that would result in
harassment as defined under the MMPA.
Marine Mammal Habitat Effects
The TMC's construction activities could have localized, temporary
impacts on marine mammal habitat and their prey by increasing in-water
sound pressure levels and slightly decreasing water quality. However,
since the proposed location is not heavily used by marine mammals and
is in close proximity to an area currently used by large passenger and
shipping vessels, and two active harbors. Construction activities are
of short duration and would likely have temporary impacts on marine
mammal habitat through increases in underwater and airborne sound.
Increased noise levels may affect acoustic habitat (see masking
discussion above) and adversely affect marine mammal prey in the
vicinity of the project area (see discussion below). During DTH,
impact, and vibratory pile driving, elevated levels of underwater noise
would ensonify the project area where both fish and mammals occur and
could affect foraging success. Additionally, marine mammals may avoid
the area during construction, however, displacement due to noise is
expected to be temporary and is not expected to result in long-term
effects to the individuals or populations.
Temporary and localized increase in turbidity near the seafloor
would occur in the immediate area surrounding the area where piles are
installed or removed. In general, turbidity associated with pile
installation is localized to about a 25-ft (7.6 m) radius around the
pile (Everitt et al., 1980). The sediments of the project site will
settle out rapidly when disturbed. Cetaceans are not expected to be
close enough to the pile driving areas to experience effects of
turbidity, and any pinnipeds could avoid localized areas of turbidity.
Local strong currents are anticipated to disburse any additional
suspended sediments produced by project activities at moderate to rapid
rates depending on tidal stage. Therefore, we expect the impact from
increased turbidity levels to be discountable to marine mammals and do
not discuss it further.
In-Water Construction Effects on Potential Foraging Habitat
The proposed activities would not result in permanent impacts to
habitats used directly by marine mammals except for the actual
footprint of the floating dock for the cruise ship dock. The total
seafloor area likely impacted by the project is relatively small
compared to the available habitat in Southcentral Alaska and does not
include any Biologically Important Areas or other habitat of known
importance. The area is highly influenced by anthropogenic activities.
Additionally, the total seafloor area affected by pile installation and
removal is a small area compared to the vast foraging area available to
marine mammals in the area. At best, the impact area provides marginal
foraging habitat for marine mammals and fishes. Furthermore, pile
driving at the project site would not obstruct movements or migration
of marine mammals.
Avoidance by potential prey (i.e., fish) of the immediate area due
to the temporary loss of this foraging habitat is also possible. The
duration of fish avoidance of this area after pile driving stops is
unknown, but a rapid return to normal recruitment, distribution and
behavior is anticipated. Any behavioral avoidance by fish of the
disturbed area would still leave significantly large areas of fish and
marine mammal foraging habitat in the nearby vicinity.
Effects on Potential Prey
Sound may affect marine mammals through impacts on the abundance,
behavior, or distribution of prey species
[[Page 9238]]
(e.g., crustaceans, cephalopods, fish, zooplankton, etc.). Marine
mammal prey varies by species, season, and location. Here, we describe
studies regarding the effects of noise on known marine mammal prey.
Fish utilize the soundscape and components of sound in their
environment to perform important functions such as foraging, predator
avoidance, mating, and spawning (e.g., Zelick and Mann, 1999; Fay,
2009). Depending on their hearing anatomy and peripheral sensory
structures, which vary among species, fishes hear sounds using pressure
and particle motion sensitivity capabilities and detect the motion of
surrounding water (Fay et al., 2008). The potential effects of noise on
fishes depends on the overlapping frequency range, distance from the
sound source, water depth of exposure, and species-specific hearing
sensitivity, anatomy, and physiology. Key impacts to fishes may include
behavioral responses, hearing damage, barotrauma (pressure-related
injuries), and mortality.
Fish react to sounds which are especially strong and/or
intermittent low-frequency sounds, and behavioral responses such as
flight or avoidance are the most likely effects. Short duration, sharp
sounds can cause overt or subtle changes in fish behavior and local
distribution. The reaction of fish to noise depends on the
physiological state of the fish, past exposures, motivation (e.g.,
feeding, spawning, migration), and other environmental factors.
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, 2002; Popper and Hastings,
2009). Several studies have demonstrated that impulse sounds might
affect the distribution and behavior of some fishes, potentially
impacting foraging opportunities or increasing energetic costs (e.g.,
Fewtrell and McCauley, 2012; Pearson et al., 1992; Skalski et al.,
1992; Santulli et al., 1999; Paxton et al., 2017). However, some
studies have shown no or slight reaction to impulse sounds (e.g.,
Wardle et al., 2001; Jorgenson and Gyselman, 2009).
SPLs of sufficient strength have been known to cause injury to fish
and fish mortality. However, in most fish species, hair cells in the
ear continuously regenerate and loss of auditory function likely is
restored when damaged cells are replaced with new cells. Halvorsen et
al., (2012a) showed that a TTS of 4-6 dB was recoverable within 24
hours for one species. Impacts would be most severe when the individual
fish is close to the source and when the duration of exposure is long.
Injury caused by barotrauma can range from slight to severe and can
cause death, and is most likely for fish with swim bladders. Barotrauma
injuries have been documented during controlled exposure to impact pile
driving (Halvorsen et al., 2012b; Casper et al., 2013), and can be
mitigated by the use of a bubble curtain (Caltrans 2020).
The most likely impact to fish from pile driving activities at the
project areas would be temporary behavioral avoidance of the area. The
duration of fish avoidance of an area after pile driving stops is
unknown, but a rapid return to normal recruitment, distribution and
behavior is anticipated.
Construction activities, in the form of increased turbidity, have
the potential to adversely affect forage fish in the project area.
Forage fish form a significant prey base for many marine mammal species
that occur 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 forage fish are expected to be minor or negligible.
Finally, exposure to turbid waters from construction activities is not
expected to be different from the current exposure; fish and marine
mammals in the Passage Canal are routinely exposed to substantial
levels of suspended sediment from natural and anthropogenic sources.
In summary, given the short daily duration of sound associated with
individual pile driving 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. Any behavioral avoidance by fish of the
disturbed area would still leave significantly large areas of fish and
marine mammal foraging habitat in the nearby vicinity. 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 this 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 primarily be by Level B harassment, as use
of the acoustic sources (i.e., vibratory or impact pile driving and
DTH) has the potential to result in disruption of behavioral patterns
for individual marine mammals. There is also some potential for
auditory injury (Level A harassment) to result for Dall's porpoise and
harbor seals, due to the cryptic nature of these species in context of
larger predicted auditory injury zones. Auditory injury is unlikely to
occur for low- and mid-frequency species and otariids, based on the
likelihood of the species in the action area, the ability to monitor
the entire smaller shutdown zone, and because of the expected ease of
detection for the former groups. The proposed mitigation and monitoring
measures are expected to minimize the severity of the taking to the
extent practicable.
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
[[Page 9239]]
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). Thresholds have also been developed identifying the
received level of in-air sound above which exposed pinnipeds would
likely be behaviorally harassed.
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, DTH drilling) and above RMS SPL 160 dB re 1 [mu]Pa for non-
explosive impulsive (e.g., impact pile driving and DTH hammering) or
intermittent (e.g., scientific sonar) sources.
TMC's proposed activity includes the use of continuous (vibratory
hammer and DTH) and impulsive (DTH and impact pile-driving) sources,
and therefore the 120 and 160 dB re 1 [mu]Pa (rms) thresholds are
applicable.
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). TMC's
proposed activity includes the use of impulsive (impact pile-driving
and DTH) and non-impulsive (vibratory hammer and DTH) sources.
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="http://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance">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 acoustic thresholds * (received level)
Hearing group ------------------------------------------------------------------------
Impulsive Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans........... Cell 1: Lpk,flat: 219 dB; Cell 2: LE,LF,24h: 199 dB.
LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans........... Cell 3: Lpk,flat: 230 dB; Cell 4: LE,MF,24h: 198 dB.
LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans.......... Cell 5: Lpk,flat: 202 dB; Cell 6: LE,HF,24h: 173 dB.
LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater)..... Cell 7: Lpk,flat: 218 dB; Cell 8: LE,PW,24h: 201 dB.
LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater).... Cell 9: Lpk,flat: 232 dB; Cell 10: LE,OW,24h: 219 dB.
LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa, and cumulative sound exposure level (LE)
has a reference value of 1[micro]Pa\2\s. In this Table, thresholds are abbreviated to reflect American
National Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as
incorporating frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript
``flat'' is being included to indicate peak sound pressure should be flat weighted or unweighted within the
generalized hearing range. The subscript associated with cumulative sound exposure level thresholds indicates
the designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
and that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could
be exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible,
it is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
exceeded.
Ensonified Area
Here, 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., impact pile driving, vibratory
pile driving and removal, and DTH).
In order to calculate distances to the Level A harassment and Level
B harassment thresholds for the methods and piles being used in this
project, NMFS used acoustic monitoring data from other locations to
develop source levels for the various pile types, sizes and methods
(Table 5). Additionally, a bubble curtain would be deployed at a depth
of 60 feet and would be used during all activities that fall within the
60-ft. isobath. Therefore, a 5dB reduction is applies to the estimated
sound source levels for driving these piles only.
[[Page 9240]]
Table 5--Observed Source Levels for Pile Installation and Removal
----------------------------------------------------------------------------------------------------------------
Pile size, method SPL (dB) SEL (dB) Reference
----------------------------------------------------------------------------------------------------------------
Bubble Curtain in use (depths of 60-ft or less)
----------------------------------------------------------------------------------------------------------------
36-in steel pile, Vibratory 161 RMS................ ....................... U.S. Navy 2015.
Installation (temporary).
36-in steel pile, Vibratory Removal 161 RMS **............. ....................... U.S. Navy 2015.
(temporary).
36-in steel pile, DTH Installation 174 RMS................ 164 SEL................ Denes et al., 2019;
(temporary). Guan and Miner, 2020;
Reyff and Heyvaert,
2019; Reyff, 2020;
Heyvaert and Reyff,
2021.
36-in steel pile, Vibratory 161 RMS **............. ....................... U.S. Navy 2015.
Installation (permanent).
36-in steel pile, Impact Installation 187 RMS **............. 179 SEL **............. U.S. Navy 2015.
(permanent).
36-in steel pile, DTH Installation 169 RMS **............. 159 SEL **............. Denes et al., 2019;
(permanent) *. Guan and Miner, 2020;
Reyff and Heyvaert,
2019; Reyff, 2020;
Heyvaert and Reyff,
2021.
----------------------------------------------------------------------------------------------------------------
No Bubble Curtain (depths greater than 60-ft)
----------------------------------------------------------------------------------------------------------------
36-in steel pile, Vibratory 166 RMS................ ....................... U.S. Navy 2015.
Installation (temporary).
36-in steel pile, Vibratory Removal 166 RMS................ ....................... U.S. Navy 2015.
(temporary).
42-in steel pile, Vibratory 168.2 RMS.............. ....................... Austin et al. 2016.
Installation.
48-in steel pile, Vibratory 168.2 RMS.............. ....................... Austin et al. 2016.
Installation.
42-in steel pile, Impact Installation 198.6 RMS.............. 186.7 SEL.............. Austin et al. 2016.
48-in steel pile, Impact Installation 198.6 RMS.............. 186.7 SEL.............. Austin et al. 2016.
36-in steel pile, DTH Installation 169 RMS **............. 159 SEL **............. Denes et al., 2019;
(temporary). Guan and Miner, 2020;
Reyff and Heyvaert,
2019; Reyff, 2020;
Heyvaert and Reyff,
2021.
42-in steel pile, DTH Installation *. 174 RMS................ 164 SEL................ Denes et al., 2019;
Guan and Miner, 2020;
Reyff and Heyvaert,
2019; Reyff, 2020;
Heyvaert and Reyff,
2021.
48-in steel pile, DTH Installation *. 174 RMS................ 171 SEL................ Denes et al., 2019;
Guan and Miner, 2020;
Reyff and Heyvaert,
2019; Reyff, 2020;
Heyvaert and Reyff,
2021.
----------------------------------------------------------------------------------------------------------------
Note: SELss = single strike sound exposure level; RMS = root mean square.
* Source levels proposed here differ from those used in TMC's application as NMFS has updated their acoustic
guidance on DTH, resulting in larger Level B harassment SPLs (<a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance#other-nmfs-acoustic-thresholds-and-tools">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance#other-nmfs-acoustic-thresholds-and-tools</a>).
** Attenuated source levels with 5dB reduction due to use of a bubble curtain during these activities (Caltrans,
2015; Austin et al., 2016).
NMFS recommends treating DTH systems as both impulsive and
continuous, non-impulsive sound source types simultaneously. Thus,
impulsive thresholds are used to evaluate Level A harassment, and
continuous thresholds are used to evaluate Level B harassment. With
regards to DTH mono-hammers, NMFS recommends proxy levels for Level A
harassment based on available data regarding DTH systems of similar
sized piles and holes (Denes et al., 2019; Guan and Miner, 2020; Reyff
and Heyvaert, 2019; Reyff, 2020; Heyvaert and Reyff, 2021) (Table 1
includes number of piles and duration; Table 5 includes sound pressure
and sound exposure levels for each pile type).
Level B Harassment Zones
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; for practical spreading equals 15
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.
The recommended TL coefficient for most nearshore environments is
the practical spreading value of 15. This value results in an expected
propagation environment that would lie between spherical and
cylindrical spreading loss conditions, which is the most appropriate
assumption for TMC's proposed activities. The Level B harassment zones
and areas of zones of influence (ZOIs) for the proposed activities are
shown in Table 6.
Level A Harassment Zones
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 installation or removal, 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. The isopleths generated by the User
Spreadsheet used the same TL coefficient as the Level B harassment zone
calculations (i.e., the practical spreading value of 15). Inputs used
in the User Spreadsheet (e.g., number of
[[Page 9241]]
piles per day, duration and/or strikes per pile) are presented in Table
1. The maximum RMS SPL, SEL, and resulting isopleths are reported in
Table 5 and 6.
Table 6--Level A and Level B Harassment Isopleths for Pile Driving Activities
----------------------------------------------------------------------------------------------------------------
Level A harassment zone (m) Level B
Activity ------------------------------------------------------------------- harassment
LF cetacean MF cetacean HF cetacean Phocids Otariids zone (m)
----------------------------------------------------------------------------------------------------------------
Bubble Curtain in use (depths of 60 ft or less)
----------------------------------------------------------------------------------------------------------------
36-in steel pile, Vibratory 5.2 0.5 7.7 3.2 0.2 5,412
Installation (temporary).......
36-in steel pile, Vibratory 5.2 0.5 7.7 3.2 0.2 5,412
Removal (temporary)............
36-in steel pile, DTH 681.1 24.5 820.9 368.8 26.9 6,310
Installation (temporary).......
36-in steel pile, Vibratory 6.8 0.6 10.1 4.2 0.3 5,412
Installation (permanent).......
36-in steel pile, Impact 2,015.1 71.7 2,400.3 1,078.4 78.5 631
Installation (permanent).......
36-in steel pile, DTH 799.7 28.4 952.6 428 31.2 6,310
Installation (permanent) *.....
----------------------------------------------------------------------------------------------------------------
No Bubble Curtain (depths greater than 60 ft)
----------------------------------------------------------------------------------------------------------------
36-in steel pile, Vibratory 11.2 1 16.6 6.8 .05 11,659
Installation (temporary).......
36-in steel pile, Vibratory 11.2 1 16.6 6.8 .05 11,659
Removal (temporary)............
42-in steel pile, Vibratory 20.6 1.8 30.5 12.5 0.9 16,343
Installation...................
48-in steel pile, Vibratory 13 1.2 19.2 7.9 0.6 16,343
Installation...................
42-in steel pile, Impact 6,570.9 233.7 7,827 3,516.4 256 3,744
Installation...................
48-in steel pile, Impact 5,014.6 178.4 5,973.1 2,683.6 195.4 3,744
Installation...................
36-in steel pile, DTH 1,484.7 52.8 1,768.5 794.6 57.9 * 39,811
Installation (temporary).......
42-in steel pile, DTH 1,722.9 61.3 2,052.2 922 67.1 * 39,811
Installation *.................
48-in steel pile, DTH 5,045.7 179.5 6,010.2 2,700.2 196.6 * 39,811
Installation *.................
----------------------------------------------------------------------------------------------------------------
* Differs from TMC's application due to difference in source level use. See Table 5.
Marine Mammal Occurrence
In this section we provide information about the occurrence of
marine mammals, including presence, local knowledge, group dynamics, or
other relevant information, that will inform the take calculations. We
also describe how the information provided above is brought together to
produce a quantitative take estimate.
Available information regarding marine mammal occurrence and
abundance in the vicinity of Passage Canal includes local knowledge,
previous marine construction projects in the Whittier area, and
available scientific literature. A summary of proposed take is in Table
7. To accurately describe species occurrence near the action area,
marine mammals were described as either common or infrequent.
To obtain more accurate estimates of potential take by Level B
harassment, TMC estimated an hourly occurrence probability of each
marine mammal species in the action area rather than a weekly or daily
estimation, since pile driving activities would not occur over an
entire day, but rather over a certain number of hours. Occurrence
probability estimates are based on conservative density approximations
for each species and factor in historic data of occurrence,
seasonality, and group size in the Passage Canal and/or nearby Prince
William Sound.
Assumptions for these hourly estimations were that common species
(Steller sea lion, harbor seal) would have two group sightings per day
in Passage Canal, and infrequent species would have three group
sightings per week in Passage Canal, or slightly fewer than one group
sighting every two days (Table 7). In these estimations, a sighting
does not equal one animal; a sighting equals one group of each
particular species. To standardize observation estimates across
species, these numbers were distilled down to obtain the hourly
occurrence probability for each species. Additionally, one day was
equated to 12 hours rather than 24 hours to obtain a rough estimate of
observations during daylight hours when pile driving and project
activities would be occurring, and to obtain more conservative
estimates of species occurrence. TMC states that this hourly estimate
provides a more accurate representation of actual possible takes in
Passage Bay. For more detailed breakdown of each species occurrence
information, see Table 7 in TMC's application.
Table 7--Estimated Occurrence of Group Sighting of Marine Mammals
----------------------------------------------------------------------------------------------------------------
Group sighting occurrence estimate
Species occurrence in the action area -----------------------------------------------
Weekly Daily Hourly
----------------------------------------------------------------------------------------------------------------
Common (Steller sea lion, harbor seal).......................... 14 2 0.17
Infrequent (humpback whale, Dall's porpoise, killer whale)...... 3 0.5 0.04
----------------------------------------------------------------------------------------------------------------
Take Estimation
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.
Using the hourly occurrence probability for a species, this was
multiplied by the estimated group size and by the number of hours of
each type of pile driving activity for total take estimate.
[[Page 9242]]
Estimated take = Hourly occurrence estimate x average group size x
hours of pile driving activity
For species infrequently seen in the Passage Canal (humpback whale,
Dall's porpoise, and killer whale) and rarely seen close to the project
location, only hours of pile driving with the largest resulting
isopleths (DTH and vibratory driving) were used to calculate these
species take estimates. Impact pile driving was excluded from these
analyses because the Level A harassment isopleth was larger than the
Level B harassment isopleth, and therefore construction would be shut
down before they approach the Level B harassment zone.
Take by Level A harassment is also requested for Dall's porpoise
and harbor seals given their frequency in the action area, the large
Level A harassment zones for HF cetaceans and phocids, the possibility
they may not be seen in the water before pile driving could be shut
down, and the fact that Level A harassment isopleths for certain pile
driving activities extend to Whittier Seafood's outfall, a known marine
mammal foraging area.
The take calculations for Level A harassment are based on the
occurrence estimate for the species in the largest Level B harassment
zone (16,343 meters) reduced by a factor for each smaller Level A
harassment isopleth. While NMFS updated the DTH source levels,
resulting in DTH having the largest Level B harassment isopleth, the
shoreline is limited in Passage Canal and the largest practical Level B
harassment isopleth is the one used by TMC for the original calculation
of take by Level A harassment. Therefore, the updated DTH values do not
impact the take calculation. The Level A harassment isopleth for each
species and specific activity was divided by the largest Level B
harassment isopleth (16,343 m), giving a species multiplier per hour
for occurrence in the smaller Level A harassment isopleth. This was
multiplied by the number of hours of the specific activity type, giving
the estimate for take by Level A harassment during that activity. For
example, the Level A harassment isopleth for phocid pinnipeds during
impact pile driving of 36-in steel piles is 2,323 meters, so Level B
harassment estimates are multiplied by a factor of 0.14 (2,323/16,343 =
0.14) to estimate take in the Level A harassment zone. All take Level A
harassment was conservatively calculated using isopleths from
unattenuated source levels. Take by Level B harassment was calculated
based on occurrence estimates for the area encompassed by the largest
isopleth generated by unattenuated source levels (i.e., all of Passage
Canal).
Additionally, the shutdown zone for phocid pinnipeds was decreased
compared to the calculated zone for pile driving activities that
encompassed the public boat harbor approximately 1,500 meters away due
to the possibility of harbor seals using the area as a haulout. The
shutdown zone was reduced to 1,360-m for impact pile driving 42- and
48-in pile sizes and DTH drilling of 48-in piles and the calculated
take by Level A harassment has been doubled for this species.
Table 8--Proposed Authorized Amount of Taking and Percent of Stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average group Take by Level Take by Level Percent of
Species Stock size A harassment B harassment Total take stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale............................ Hawaii DPS.................. 2.4 0 22 22 <1
WNP DPS..................... 0 1 1 <1
Mexico DPS.................. 0 2 2 <1
Dall's Porpoise........................... Alaska...................... 4.3 9 36 45 <1
Killer Whale *............................ Alaska Resident............. 14 0 116 116 6
GOA/Aleutian Islands/Bering 0 29 29 4.9
Sea Transient.
Harbor Seal............................... Prince William Sound........ 3.5 40 170 210 <1
Steller Sea Lion.......................... Western US.................. 4 0 218 218 <1
--------------------------------------------------------------------------------------------------------------------------------------------------------
* AT1 transient stock take calculation resulted in 0 takes, therefor no takes were requested or are proposed for authorization.
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.
NMFS proposed the following mitigation measures be implemented for
TMC's pile installation and removal activities.
Mitigation Measures
TMC must follow mitigation measures as specified below:
<bullet> Ensure that construction supervisors and crews, the
monitoring team, and relevant TMC staff are trained prior to the start
of all pile driving and DTH activity, so that responsibilities,
communication procedures, monitoring protocols, and operational
procedures are clearly understood. New personnel
[[Page 9243]]
joining during the project must be trained prior to commencing work;
<bullet> Employ Protected Species Observers (PSOs) and establish
monitoring locations as described in the application, the Marine Mammal
Monitoring Plan, and the IHA. The Holder must monitor the project area
to the maximum extent possible based on the required number of PSOs,
required monitoring locations, and environmental conditions. For all
pile driving and removal at least one PSO must be used. The PSO will be
stationed as close to the activity as possible;
<bullet> The placement of the PSOs during all pile driving and
removal and DTH activities will ensure that the entire shutdown zone is
visible during pile installation. Should environmental conditions
deteriorate such that marine mammals within the entire shutdown zone
will not be visible (e.g., fog, heavy rain), pile driving and removal
must be delayed until the PSO is confident marine mammals within the
shutdown zone could be detected;
<bullet> Monitoring must take place from 30 minutes prior to
initiation of pile driving or DTH activity (i.e., pre-clearance
monitoring) through 30 minutes post-completion of pile driving or DTH
activity;
<bullet> Pre-start clearance monitoring must be conducted during
periods of visibility sufficient for the lead PSO to determine that the
shutdown zones indicated in Table 9 are clear of marine mammals. Pile
driving and DTH may commence following 30 minutes of observation when
the determination is made that the shutdown zones are clear of marine
mammals;
<bullet> TMC must use soft start techniques when impact pile
driving. Soft start requires contractors to provide an initial set of
three strikes at reduced energy, followed by a 30-second waiting
period, then two subsequent reduced-energy strike sets. A soft start
must be implemented at the start of each day's impact pile driving and
at any time following cessation of impact pile driving for a period of
30 minutes or longer; and
<bullet> If a marine mammal is observed entering or within the
shutdown zones indicated in Table 9, pile driving and DTH must be
delayed or halted. If pile driving is delayed or halted due to the
presence of a marine mammal, the activity may not commence or resume
until either the animal has voluntarily exited and been visually
confirmed beyond the shutdown zone (Table 9) or 15 minutes have passed
without re-detection of the animal (30 minutes for large cetaceans);
<bullet> As proposed by the applicant, in water activities will
take place only between civil dawn and civil dusk when PSOs can
effectively monitor for the presence of marine mammals; during
conditions with a Beaufort Sea State of 4 or less; when the entire
shutdown zone and adjacent waters are visible (e.g., monitoring
effectiveness in not reduced due to rain, fog, snow, etc.). Pile
driving may continue for up to 30 minutes after sunset during evening
civil twilight, as necessary to secure a pile for safety prior to
demobilization during this time. The length of the post- activity
monitoring period may be reduced if darkness precludes visibility of
the shutdown and monitoring zones.
Shutdown Zones
TMC will establish shutdown 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
mammal (or in anticipation of an animal entering the defined area).
Shutdown zones would be based upon the Level A harassment zone for each
pile size/type and driving method where applicable, as shown in Table
9.
A minimum shutdown zone of 35 m would be applied for all in-water
construction activities if the Level A harassment zone is less than 35
m (i.e., vibratory pile driving). A 10 m shutdown zone would also serve
to protect marine mammals from collisions with project vessels during
pile driving and other construction activities, such as barge
positioning or drilling. If an activity is delayed or halted due to the
presence of a marine mammal, the activity may not commence or resume
until either the animal has voluntarily exited and been visually
confirmed beyond the shutdown zone indicated in Table 9 or 15 minutes
have passed without re-detection of the animal. Construction activities
must be halted upon observation of a species for which incidental take
is not authorized or a species for which incidental take has been
authorized but the authorized number of takes has been met entering or
within the harassment zone.
All marine mammals will 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 will continue and the animal's presence within the estimated
harassment zone will be documented.
TMC would also establish shutdown zones for all marine mammals for
which take has not been authorized or for which incidental take has
been authorized but the authorized number of takes has been met. These
zones are equivalent to the Level B harassment zones for each activity.
If a marine mammal species not covered under this IHA enters the
shutdown zone, all in-water activities will cease until the animal
leaves the zone or has not been observed for at least 1 hour, and NMFS
will be notified about species and precautions taken. Pile removal will
proceed if the non-IHA species is observed to leave the Level B
harassment zone or if 1 hour has passed since the last observation.
If shutdown and/or clearance procedures would result in an imminent
safety concern, as determined by TMC or its designated officials, the
in-water activity will be allowed to continue until the safety concern
has been addressed, and the animal will be continuously monitored.
Table 9--Proposed Shutdown Zones and Monitoring Zones
--------------------------------------------------------------------------------------------------------------------------------------------------------
Minimum shutdown zone
------------------------------------------------------------------------- Harassment
Activity Low-Frequency Mid-Frequency High-Frequency zone
(LF) Cetaceans (MF) Cetaceans (HF) Cetaceans Phocid Otariid
--------------------------------------------------------------------------------------------------------------------------------------------------------
Barge movements, pile positioning, etc.\1\........................ 10 10 10 10 10
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bubble Curtain in use (depths of 60-ft or less)
--------------------------------------------------------------------------------------------------------------------------------------------------------
36-in steel pile, Vibratory Installation (temporary).............. 10 10 10 10 10 5,415
36-in steel pile, Vibratory Removal (temporary)................... 10 10 10 10 10 5,415
36-in steel pile, DTH Installation (temporary).................... 700 35 825 370 35 6,310
36-in steel pile, Vibratory Installation (permanent).............. 10 10 10 10 10 5,415
[[Page 9244]]
36-in steel pile, Impact Installation (permanent)................. 2,055 80 2,400 1,100 80 635
36-in steel pile, DTH Installation(permanent)..................... 800 35 1,000 430 35 6,310
--------------------------------------------------------------------------------------------------------------------------------------------------------
No Bubble Curtain (depths greater than 60-ft)
--------------------------------------------------------------------------------------------------------------------------------------------------------
36-in steel pile, Vibratory Installation (temporary).............. 35 35 35 15 15 11,660
36-in steel pile, Vibratory Removal (temporary)................... 35 35 35 15 15 11,660
42-in steel pile, Vibratory Installation.......................... 35 35 35 15 15 16,345
48-in steel pile, Vibratory Installation.......................... 35 35 35 15 15 16,345
42-in steel pile, Impact Installation............................. 6,575 260 7,830 * 1,360 260 3,745
48-in steel pile, Impact Installation............................. 5,015 200 5,975 * 1,360 200 3,745
36-in steel pile, DTH Installation (temporary).................... 1,485 70 1,770 795 70 ** 16,345
42-in steel pile, DTH Installation................................ 1,770 70 2,055 925 70 ** 16,345
48-in steel pile, DTH Installation................................ 5,050 200 6,015 * 1,360 200 ** 16,345
--------------------------------------------------------------------------------------------------------------------------------------------------------
* For phocids (harbor seals) only, the Level A shutdown zone would be reduced to 1,360 m for impact pile driving of 42- and 48-in piles and DTH drilling
of 48-in piles to exclude the Whittier Public Boat Harbor.
** Differs from Table 5 Level B harassment zone for DTH because 39,811 m extends longer than Passage Canal, so land masses would block sound
transmission and distances would be truncated. It would also be impractical to monitor this whole zone outside of Passage Canal. Instead, DTH
monitoring zone would be the entirety of the Passage Canal and equivalent to the largest Level B harassment zone.
Protected Species Observers
The placement of PSOs during all construction 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 the remaining Level
A harassment and the Level B harassment zones to the extent
practicable. Monitoring zones provide utility for observing by
establishing monitoring protocols for areas adjacent to the shutdown
zones. Monitoring zones enable 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-Activity Monitoring
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 that 30-minute period.
If a marine mammal is observed within the shutdown zones listed in
Table 10, 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).
Soft-Start Procedures
Soft-start procedures provide additional protection to marine
mammals by providing warning and/or giving marine mammals a chance to
leave the area prior to the hammer operating at full capacity. For
impact pile driving, contractors would be required to provide an
initial set of three strikes from the hammer at reduced energy,
followed by a 30-second waiting period, then two subsequent reduced-
energy strike sets. Soft-start would be implemented at the start of
each day's impact pile driving and at any time following cessation of
impact pile driving for a period of 30 minutes or longer.
Bubble Curtain
A bubble curtain must be employed during all pile installation and
removal in depths of 60 ft. or less. The bubble curtain must be
deployed in manner guaranteed to distribute air bubbles around 100
percent of the piling perimeter 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 mudline contact. No parts of the ring or other
objects may prevent full mudline 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, as
well as other measures considered by NMFS, NMFS has preliminarily
determined that the proposed mitigation measures provide the means
effecting the least practicable impact on the affected species or
stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance.
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);
[[Page 9245]]
<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 action; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
<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
Marine mammal monitoring must be conducted in accordance with the
conditions in this section, the Monitoring Plan, and this IHA. Marine
mammal monitoring during pile driving activities would be conducted by
PSOs meeting NMFS' the following requirements:
<bullet> Independent PSOs (i.e., not construction personnel) who
have no other assigned tasks during monitoring periods would be used;
<bullet> At least one PSO would have prior experience performing
the duties of a PSO during construction activity pursuant to a NMFS-
issued incidental take authorization;
<bullet> Other PSOs may substitute education (degree in biological
science or related field) or training for experience; and
<bullet> Where a team of three or more PSOs is required, a lead
observer or monitoring coordinator would be designated. The lead
observer would be required to have prior experience working as a marine
mammal observer during construction.
PSOs must have the following additional qualifications:
<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, times and reason for implementation
of mitigation (or why mitigation was not implemented when required);
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;
<bullet> TMC must employ up to four PSOs during all pile driving
and DTH activities. A minimum of two PSOs (including the lead PSO) must
be assigned to the active pile driving or DTH location to monitor the
shutdown zones and as much of the Level B harassment zones as possible.
<bullet> TMC must establish the following monitoring locations with
the best views of monitoring zones as described in the IHA and Marine
Mammal Monitoring Plan.
<bullet> Two to four PSOs will be onsite during in-water activities
associated with the Whittier Head of the Bay Cruise Ship Dock Project,
likely stationed in the following locations PSOs would likely be
located at Station 1: stationed just to the south of the site on the
shore, Station 2: stationed off Depot Road near the freight loading
dock, Station 3: stationed along the shoreline northeast of the Emerald
Cove Trailhead, and Station 4: stationed on a boat triangulating an
area between Emerald Island, the north shore of Passage Canal,
southeast towards Gradual Point, and back southwest toward Trinity
Point and Emerald Island as shown in Figure 8 of the Marine Mammal
Monitoring Plan. All PSOs would have access to high-quality binoculars,
range finders to monitor distances, and a compass to record bearing to
animals as well as radios or cells phones for maintaining contact with
work crews.
Monitoring would be conducted 30 minutes before, during, and 30
minutes after all in water construction activities. In addition, PSOs
would record all incidents of marine mammal occurrence, regardless of
distance from activity, and would document any behavioral reactions in
concert with distance from piles being driven or removed. Pile driving
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.
TMC shall conduct briefings between construction supervisors and
crews, PSOs, TMC staff prior to the start of all pile driving
activities and when new personnel join the work. These briefings would
explain responsibilities, communication procedures, marine mammal
monitoring protocol, and operational procedures.
Acoustic Monitoring
Acoustic monitoring must be conducted in accordance with the
Acoustic Monitoring Plan. TMC must conduct hydroacoustic monitoring of
two (one 36-in and one 48-in) piles each from different locations
during DTH drilling.
Reporting
A draft marine mammal monitoring report will be submitted to NMFS
within 90 days after the completion of pile driving and removal
activities, or 60 days prior to a requested date of issuance from any
future IHAs for projects at the same location, whichever comes first.
The report will 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., impact, vibratory, or DTH) and the
total equipment duration for vibratory removal or DTH for each pile or
hole or total number of strikes for each pile (impact driving);
<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:
[cir] Name of PSO who sighted the animal(s) and PSO location and
activity at the time of sighting;
[cir] Time of sighting;
[cir] Identification of the animal(s) (e.g., genus/species, lowest
possible taxonomic level, or unidentifiable), PSO confidence in
identification, and the
[[Page 9246]]
composition of the group if there is a mix of species;
[cir] Distance and bearing of each marine mammal observed relative
to the pile being driven for each sightings (if pile driving was
occurring at time of sighting);
[cir] Estimated number of animals (min/max/best estimate);
[cir] Estimated number of animals by cohort (adults, juveniles,
neonates, group composition, sex class, etc.);
[cir] Animal's closest point of approach and estimated time spent
within the harassment zone;
[cir] 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 and shutdown zones; by species;
<bullet> Detailed information about any implementation of any
mitigation triggered (e.g., shutdowns and delays), a description of
specific actions that ensured, and resulting changes in behavior of the
animal(s), if any; and
<bullet> If visibility degrades to where PSO(s) cannot view the
entire harassment zones, additional PSOs may be positioned so that the
entire width is visible, or work will be halted until the entire width
is visible to ensure that any humpback whales entering or within the
harassment zone are detected by PSOs.
If no comments are received from NMFS within 30 days, the draft
final report will constitute the final report. If comments are
received, a final report addressing NMFS comments must be submitted
within 30 days after receipt of comments.
Acoustic Monitoring Plan
The report must include:
<bullet> Type and size of pile being driven, substrate type, method
of driving during recordings (e.g., hammer model, energy), and total
pile driving duration;
<bullet> Whether a sound attenuation device is used and, if so, a
detailed description of the device and the duration of its use per
pile;
<bullet> DTH: Number of strikes and strike rate, depth of substrate
to penetrate; pulse duration and mean, median, and maximum sound levels
(dB re: 1 [micro]Pa); root mean square sound pressure level (SPLrms),
cumulative sound exposure level (SEL<INF>cum</INF>), peak sound
pressure level (SPL<INF>peak</INF>), and single strike exposure sound
level (SEL<INF>s-s</INF>);
<bullet> One-third octave band spectrum and power spectral density
plot.
<bullet> Evaluation of acoustic sound record levels for pile
driving activities (DTH).
<bullet> Environmental data, including but not limited to, the
following: wind speed and direction, air temperature, humidity, surface
water temperature, water depth, wave height, weather conditions, and
other factors that could contribute to influencing the airborne and
underwater sound levels (e.g., aircraft, boats, etc.)
Reporting Injured or Dead Marine Mammals
In the event that personnel involved in the construction activities
discover an injured or dead marine mammal, the IHA-holder must
immediately cease the specified activities and report the incident to
the Office of Protected Resources (OPR)
(<a href="/cdn-cgi/l/email-protection#19494b37504d4937547677706d766b70777e4b7c69766b6d6a5977767878377e766f"><span class="__cf_email__" data-cfemail="c59597eb8c9195eb88aaabacb1aab7acaba297a0b5aab7b1b685abaaa4a4eba2aab3">[email protected]</span></a>), NMFS and to the Alaska Regional
Stranding Coordinator as soon as feasible. If the death or injury was
clearly caused by the specified activity, TMC must immediately cease
the specified activities until NMFS is able to review the circumstances
of the incident and determine what, if any, additional measures are
appropriate to ensure compliance with the terms of the IHA. The IHA-
holder must not resume their activities until notified by NMFS. The
report must include the following information:
<bullet> Time, date, and location (latitude/longitude) of the first
discovery (and updated location information if known and applicable);
<bullet> Species identification (if known) or description of the
animal(s) involved;
<bullet> Condition of the animal(s) (including carcass condition if
the animal is dead);
<bullet> Observed behaviors of the animal(s), if alive;
<bullet> If available, photographs or video footage of the
animal(s); and
<bullet> General circumstances under which the animal was
discovered.
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, our analysis applies to all species listed in
Table 2 for which take could occur, given that NMFS expects the
anticipated effects of the proposed pile driving/removal and DTH on
different marine mammal stocks to be similar in nature. Where there are
meaningful differences between species or stocks, or groups of species,
in anticipated individual responses to activities, impact of expected
take on the population due to differences in population status, or
impacts on habitat, NMFS has identified species-specific factors to
inform the analysis.
Pile driving and DTH 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 and, for some species, Level A
harassment from underwater sounds generated by pile driving. Potential
takes could occur if individuals are present in the ensonified zone
when these activities are underway.
No serious injury or mortality would be expected, even in the
absence of required mitigation measures, given the nature of the
activities. Further, no take by Level A harassment is anticipated for
humpback whales, killer whales, or Steller sea lion due to the
application of planned mitigation measures, such as shutdown zones that
encompass the Level A harassment zones for these species and the rarity
of these species near the action area. The potential for harassment
would be minimized
[[Page 9247]]
through the construction method and the implementation of the planned
mitigation measures (see Proposed Mitigation section).
Take by Level A harassment is proposed for two species (Dall's
porpoise and harbor seal) as the Level A harassment zones exceed the
size of the shutdown zones for specific construction scenarios.
Additionally these species could be found more often near the action
area and are cryptic in nature. Therefore, there is the possibility
that an animal could enter a Level A harassment zone without being
detected, and remain within that zone for a duration long enough to
incur PTS. Level A harassment of these species is proposed to be
conservative. Any take by Level A harassment is expected to arise from,
at most, a small degree of PTS (i.e., minor degradation of hearing
capabilities within regions of hearing that align most completely with
the energy produced by impact pile driving such as the low-frequency
region below 2 kHz), not severe hearing impairment or impairment within
the ranges of greatest hearing sensitivity. Animals would need to be
exposed to higher levels and/or longer duration than are expected to
occur here in order to incur any more than a small degree of PTS.
Further, the amount of take proposed for authorization by Level A
harassment is very low for both marine mammal stocks and species. If
hearing impairment occurs, it is most likely that the affected animal
would lose only a few decibels in its hearing sensitivity. Due to the
small degree anticipated, any PTS potential incurred would not be
expected to affect the reproductive success or survival of any
individuals, much less result in adverse impacts on the species or
stock.
Additionally, some subset of the individuals that are behaviorally
harassed could also simultaneously incur some small degree of TTS for a
short duration of time. However, since the hearing sensitivity of
individuals that incur TTS is expected to recover completely within
minutes to hours, it is unlikely that the brief hearing impairment
would affect the individual's long-term ability to forage and
communicate with conspecifics, and would therefore not likely impact
reproduction or survival of any individual marine mammal, let alone
adversely affect rates of recruitment or survival of the species or
stock.
The Level A harassment zones identified in Table 6 are based upon
an animal exposed to pile driving or DTH up to four piles per day.
Given the short duration to impact drive or vibratory install or
extract, or use DTH drilling, each pile and break between pile
installations (to reset equipment and move piles into place), an animal
would have to remain within the area estimated to be ensonified above
the Level A harassment threshold for multiple hours. This is highly
unlikely give marine mammal movement in the area. If an animal was
exposed to accumulated sound energy, the resulting PTS would likely be
small (e.g., PTS onset) at lower frequencies where pile driving energy
is concentrated, and unlikely to result in impacts to individual
fitness, reproduction, or survival.
The nature of the pile driving project precludes the likelihood of
serious injury or mortality. For all species and stocks, take would
occur within a limited, confined area (adjacent to the project site) of
the stock's range. Level A and Level B harassment will be reduced to
the level of least practicable adverse impact through use of mitigation
measures described herein. Further, the amount of take proposed to be
authorized is extremely small when compared to stock abundance.
Behavioral responses of marine mammals to pile driving, pile
removals, and DTH at the sites in the Passage Canal are expected to be
mild, short term, and temporary. Marine mammals within the Level B
harassment zones may not show any visual cues they are disturbed by
activities or they could become alert, avoid the area, leave the area,
or display other mild responses that are not observable such as changes
in vocalization patterns. Given that pile driving, pile removal, and
DTH would occur for only a portion of the project's duration, any
harassment occurring would be temporary. Additionally, many of the
species present in region would only be present temporarily based on
seasonal patterns or during transit between other habitats. These
temporary present species would be exposed to even smaller periods of
noise-generating activity, further decreasing the impacts.
For all species, there are no known Biologically Important Areas
(BIAs) near the project area that would be impacted by TMC's planned
activities. While southcentral Alaska is considered an important area
for feeding humpback whales between March and May (Ellison et al.,
2012), it is not currently designated as critical habitat for humpback
whales (86 FR 21082; April 21, 2021).
In addition, it is unlikely that minor noise effects in a small,
localized area of habitat would have any effect on each stock's ability
to recover. In combination, we believe that these factors, as well as
the available body of evidence from other similar activities,
demonstrate that the potential effects of the specified activities will
have only minor, short-term effects on individuals. The specified
activities are not expected to impact rates of recruitment or survival
and will therefore not result in population-level impacts.
In summary and as described above, the following factors primarily
support our preliminary determination that the impacts resulting from
this activity are not expected to adversely affect the species or stock
through effects on annual rates of recruitment or survival:
<bullet> No serious injury or mortality is anticipated or
authorized.
<bullet> Authorized Level A harassment would be very small amounts
and of low degree;
<bullet> Level A harassment takes of only Dall's porpoise and
harbor seals;
<bullet> For all species, the Passage Canal is a very small and
peripheral part of their range;
<bullet> The intensity of anticipated takes by Level B harassment
is relatively low for all stocks. Level B harassment would be primarily
in the form of behavioral disturbance, resulting in avoidance of the
project areas around where impact or vibratory pile driving is
occurring, with some low-level TTS that may limit the detection of
acoustic cues for relatively brief amounts of time in relatively
confined footprints of the activities;
<bullet> Effects on species that serve as prey for marine mammals
from the activities are expected to be short-term and, therefore, any
associated impacts on marine mammal feeding are not expected to result
in significant or long-term consequences for individuals, or to accrue
to adverse impacts on their populations;
<bullet> The ensonified areas are very small relative to the
overall habitat ranges of all species and stocks, and would not
adversely affect ESA-designated critical habitat for any species or any
areas of known biological importance;
<bullet> The lack of anticipated significant or long-term negative
effects to marine mammal habitat; and
<bullet> TMC would implement mitigation measures including soft-
starts and shutdown zones to minimize the numbers of marine mammals
exposed to injurious levels of sound, and to ensure that take by Level
A harassment is, at most, a small degree of PTS;
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
[[Page 9248]]
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 small numbers of incidental take may be
authorized under sections 101(a)(5)(A) and (D) of the MMPA for
specified activities other than military readiness activities. The MMPA
does not define small numbers and so, in practice, where estimated
numbers are available, NMFS compares the number of individuals taken to
the most appropriate estimation of abundance of the relevant species or
stock in our determination of whether an authorization is limited to
small numbers of marine mammals. When the predicted number of
individuals to be taken is fewer than one-third of the species or stock
abundance, the take is considered to be of small numbers. Additionally,
other qualitative factors may be considered in the analysis, such as
the temporal or spatial scale of the activities.
The amount of take NMFS proposes to authorize is below one third of
the estimated stock abundance for all species (in fact, take of
individuals is less than five percent of the abundance of the affected
stocks, see Table 7). This is likely a conservative estimate because we
assume all takes are of different individual animals, which is likely
not the case. Some individuals may return multiple times in a day, but
PSOs would count them as separate takes if they cannot be individually
identified.
The most recent estimate for the Alaska stock of Dall's porpoise
was 13,110 animals however this number just accounts for a portion of
the stock's range. Therefore, the 45 takes of this stock proposed for
authorization is believed to be an even smaller portion of the overall
stock abundance.
Based on the analysis contained herein of the proposed activity
(including the proposed mitigation and monitoring measures) and the
anticipated take of marine mammals, NMFS preliminarily finds that small
numbers of marine mammals will be taken relative to the population size
of the affected species or stocks.
Unmitigable Adverse Impact Analysis and Determination
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.
The Alutiiq and Eyak people of Prince William Sound traditionally
harvested marine mammals, however the last recorded harvest of marine
mammals in Whittier was in 1990, where it was reported that 7 marine
mammals were harvested (ADF&G 2022b). Other Prince William Sound
coastal communities such as Cordova, Chenega, and Tatitlek report
recent subsistence harvest or use of marine mammals. Harvest of harbor
seals and Steller sea lions was reported in Tatitlek in 2014, the
latest year for which data is available from ADF&G's Community
Subsistence Information System (ADF&G 2022b).
Subsistence hunters in Prince William Sound report having to travel
farther from their home communities to be successful when harvesting
marine mammals (Keating et al. 2020). However, their range was not
reported to extend into Passage Canal, as all three communities are
located at least 60 miles away by boat (Fall and Zimpelman 2016).
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 because:
<bullet> there is no recent recorded subsistence harvest of marine
mammals in the area;
<bullet> construction activities are localized and temporary;
<bullet> mitigation measures will be implemented to minimize
disturbance of marine mammals in the action area; and,
<bullet> the project will not result in significant changes to
availability of subsistence resources.
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 TMC'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 US Steller Sea Lion,
Western North Pacific Humpback whale, and the California/Oregon/
Washington Humpback whale, which are listed under the ESA.
The Permits and Conservation Division has requested initiation of
section 7 consultation with the Alaska Region for the issuance of this
IHA. NMFS will conclude the ESA consultation prior to reaching a
determination regarding the issuance of the authorization.
Proposed Authorization
As a result of these preliminary determinations, NMFS proposes to
issue an IHA to TMC for conducting Whittier head of the Bay Cruise Ship
Dock project in Whittier, Alaska, 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#active-authorizations">https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities#active-authorizations</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. 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
[[Page 9249]]
Proposed Activities section of this notice is planned or (2) the
activities as described in the Description of Proposed Activities
section of this notice would not be completed by the time the IHA
expires and a renewal would allow for completion of the activities
beyond that described in the Dates and Duration section of this notice,
provided all of the following conditions are met:
<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 one 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: February 8, 2023.
Kimberly Damon-Randall,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2023-02997 Filed 2-10-23; 8:45 am]
BILLING CODE 3510-22-P
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</html>Indexed from Federal Register on February 13, 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.