[Federal Register Volume 83, Number 241 (Monday, December 17, 2018)]
[Notices]
[Pages 64541-64563]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-27258]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XG628
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to the Railroad Dock Dolphin
Installation Project, Skagway, 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 White Pass & Yukon Route
(WP&YR) for authorization to take marine mammals incidental to the
Railroad Dock dolphin installation project in Skagway, 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-year renewal that
could be issued under certain circumstances and if all requirements are
met, as described in Request for Public Comments at the end of this
notice. NMFS will consider public comments prior to making any final
decision on the issuance of the requested MMPA authorizations and
agency responses will be summarized in the final notice of our
decision.
DATES: Comments and information must be received no later than January
16, 2019.
ADDRESSES: Comments should be addressed to Jolie Harrison, Chief,
Permits and Conservation Division, Office of Protected Resources,
National Marine Fisheries Service. Physical comments should be sent to
1315 East-West Highway, Silver Spring, MD 20910 and electronic comments
should be sent to [email protected].
Instructions: NMFS is not responsible for comments sent by any
other method, to any other address or individual, or received after the
end of the comment period. Comments received electronically, including
all attachments, must not exceed a 25-megabyte file size. Attachments
to electronic comments will be accepted in Microsoft Word or Excel or
Adobe PDF file formats only. All comments received are a part of the
public record and will generally be posted online at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities 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: Wendy Piniak, Office of Protected
Resources, NMFS, (301) 427-8401. Electronic copies of the application
and supporting documents, as well as a list of the references cited in
this document, may be obtained online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities. 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
[[Page 64542]]
geographical region if certain findings are made and either regulations
are issued or, if the taking is limited to harassment, a notice of a
proposed incidental take authorization may be provided to the public
for review.
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other means of effecting the least practicable adverse
impact on the affected species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of such species or stocks for
taking for certain subsistence uses (referred to in shorthand as
``mitigation''); and requirements pertaining to the mitigation,
monitoring and reporting of such takings are set forth.
The NDAA (Pub. L. 108-136) removed the ``small numbers'' and
``specified geographical region'' limitations indicated above and
amended the definition of ``harassment'' as it applies to a ``military
readiness activity.'' The definitions of all applicable MMPA statutory
terms cited above are included in the relevant sections below.
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must review our proposed action (i.e., the issuance of an
incidental harassment authorization) with respect to potential impacts
on the human environment.
This action is consistent with categories of activities identified
in Categorical Exclusion B4 (incidental harassment authorizations with
no anticipated serious injury or mortality) of the Companion Manual for
NOAA Administrative Order 216-6A, which do not individually or
cumulatively have the potential for significant impacts on the quality
of the human environment and for which 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 August 21, 2018, NMFS received a request from WP&YR for an IHA
to take marine mammals incidental to the Railroad Dock dolphin
installation project in Skagway, Alaska. WP&YR submitted a revised
version of the application on November 9, 2018 which was deemed
adequate and complete on November 15, 2018. WP&YR's request is for take
of seven species of marine mammals by Level B harassment and Level A
harassment incidental to impact pile driving, vibratory pile driving
and removal, and down-the-hole drilling activities. Neither WP&YR nor
NMFS expects serious injury or mortality to result from this activity
and, therefore, an IHA is appropriate. In-water activities (pile
installation and extraction) associated with the project are scheduled
to begin February 1, 2019, and be completed April 30, 2019.
Description of Proposed Activity
Overview
WP&YR requested the authorization of take of small numbers of
marine mammals incidental to pile driving/removal and down-the-hole
drilling associated with the installation of two new 200-ton pile
supported mooring dolphins in Skagway Harbor, Alaska. The purpose of
the project is to provide ample safe moorage when both Norwegian
Breakaway and Royal Caribbean Quantum class cruise ship vessels are in
port. The existing dolphin infrastructure does not allow for both
cruise ships to be moored at the dock at the same time. The additional
dolphins would allow for both ships to be docked simultaneously. To
facilitate dual mooring, the proposed project includes the installation
of two 200-ton dolphins, each comprised of six 42-inch steel permanent
piles 300 feet in length. WP&YR would also install and subsequently
remove 14 36-inch template (temporary) piles (200 feet in length) at
the two dolphin locations which are approximately 100 feet and 200
feet, respectively, south of the existing southernmost mooring dolphin
at the WP&YR Railroad Dock. The template and permanent piles are
comprised of two to three 100-feet long segments which would be spliced
(i.e., welded) together as they are installed. All temporary and
permanent piles would require a combination of three pile installation
methods: Vibratory driving, impact driving, and down-the-hole drilling.
Sounds produced by these activities may result in take, by Level A and
Level B harassment, of marine mammals located in Taiya Inlet, Alaska.
Dates and Duration
In-water activities (pile installation and extraction) associated
with the project are scheduled to begin February 1, 2019, and be
completed April 30, 2019. Pile installation and removal would occur for
89 days over the course of the three months. WP&YR anticipates up to 10
hours of activity (vibratory driving, impact driving, and down-the-hole
drilling) during daylight hours would occur per day.
Specific Geographic Region
The activities would occur at the south end of WP&YR's Railroad
Dock located in Skagway Harbor, Alaska. Skagway Harbor is located at
the southwestern end of the 2.5-mile (mi)-long Skagway River valley.
Three anadromous rivers are located near the project site including
Skagway River, Taiya River, and Pullen Creek. The Skagway and Taiya
Rivers empty into Taiya Inlet at the head of Lynn Canal west and
northwest of the project site respectively. Pullen Creek empties into
the Taiya Inlet on the southeast side of the valley northeast of the
project site. Taiya Inlet/Lynn Canal is the northernmost fjord on the
Inside Passage of the south coast of Alaska. The project site is
located south of ADL 108521 and seaward of upland Lot 8, U.S. Survey
5110; Latitude 59.44[deg] North (N), Longitude 135.33[deg] West (W)
(see Figures 1-3 of WP&YR's application). Limited information is
available on the benthic habitat beneath the Railroad Dock, however the
basin is composed of glacial till sediments, consisting of mud, silty
gravel, cobbles and boulders. The shoreline along Railroad dock is
armored with riprap and contains little to no riparian vegetation. This
armoring extends to below the mean higher high water (MHHW) mark to an
unknown depth. At the project site, the Taiya Inlet is approximately 2
kilometers (km) wide and water depth ranges from approximately 100-200
feet (ft) (30-60 meters (m)); however water depth in Taiya Inlet
reaches over 500 ft (152 m), within and south of the project area.
Skagway Harbor is frequently visited by cruise ship vessels during
the summer and is a site of recreational and commercial activity.
Vessels must travel up Taiya Inlet to enter the Skagway Harbor.
Detailed Description of Specific Activity
To facilitate dual mooring of large cruise ship vessels, the
proposed Railroad Dock dolphin installation
[[Page 64543]]
project includes installation of two 200-ton dolphins. Two crane
barges, one material barge, and three work boats (each under 25 feet)
would be used to complete the project. Barges would be moored on-site
for the duration of construction. Each dolphin would require the
installation and removal of seven 36-inch steel pipe template piles (14
total) and the installation six 42-inch steel pipe permanent piles (12
total). The temporary template piles would be installed to aid in
construction and would be removed after the permanent dolphin piles are
installed. Each temporary template pile would be approximately 200 ft
in length and would consist of up to two sections that would be spliced
(e.g. welded) together as they are installed (for a total of up to 28
segments). Each permanent pile would be approximately 300 ft in length
and would consist of up to three sections that would be spliced
together as they installed (for a total of 36 segments).
Template and permanent piles would be installed in water depths up
to 140-feet deep and into loose substrate that is intermixed with
cobbles and boulder-sized rocks. Due to the nature of deep-water pile
installation in loose sediment, each pile (consisting of two to three
segments) would be installed using a combination of installation
methods: Vibratory hammer, impact hammer, and drilling (Table 1).
Removal of template piles would only require the use of a vibratory
hammer. It may be necessary to switch between installation methods
multiple times per day depending on encountered conditions. However, no
activities would occur simultaneously (e.g., only one installation
method would occur on one pile at any time). Throughout the project,
one crane would be dedicated to drilling only and the second crane
would alternate between the vibratory and impact hammers (as noted,
only one crane would be active at any given time). In addition to
alternating between installation methods, the project would require the
piles segments to be spliced together to make the piles longer before
continuing installation. That is, the first segment of pile would be
installed using one or more methods; the second segment would then be
welded to the first segment and the process would be repeated until the
entire pile is installed.
Table 1--Pile Installation and Removal Equipment
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Pile installation equipment Model/size Description/purpose
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Crane....................... 200-250-ton barge Install piles, set
with a 200-250-ft dolphin caps, set
boom (up to 2 catwalks, move
cranes). material, etc.
Vibratory Hammer............ APE 200 or Advance pile through
equivalent. overburden to
vibratory refusal.
Impact Hammer............... Delmag D100 Diesel Advance pile through
hammer or overburden once
equivalent. vibratory refusal
has been reached.
Drill....................... Rock Anchor (8-inch A drill is inserted
hole): ICE-HS-27 through the pile
Top drive down-hole all the way down to
hammer PDQL-80 or bedrock. The drill
equivalent. breaks up rock into
Socket (42-inch small flakes
hole): PPV ring bit (tailings) which
MF34 down hole are removed from
hammer or the drilled hole as
equivalent. the pile or casing
advances.
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The tips of all template piles would be embedded approximately 60
ft beneath the mudline using impact or vibratory hammering and
drilling. The structural design of the dolphins requires the tips of
all permanent piles to bear on and be socketed in bedrock located 100-
200 ft beneath the mudline. During installation, some or all piles will
encounter obstructions prior to reaching final tip depth and will
require drilling through obstructions to meet project specifications.
The first segment of each pile would be impact or vibratory driven to
first refusal. First refusal occurs when the pile tip cannot be
advanced any further with a vibratory or impact hammer. This will most
likely occur when the pile tip is located on an obstruction (prior to
reaching bedrock) or at bedrock. To determine whether the pile tip has
reached bedrock, the contractor would then drill past the segment tip.
If the drill advances up to 20 ft past the segment tip through rock,
bedrock is encountered. If the drill ``punches through'' the
obstruction and encounters soft overburden material, the pile would
continue to be advanced using drilling, impact, or vibratory methods.
Once second refusal is reached, bedrock would again need to be verified
by drilling up to 20-ft past the pile tip into bedrock. This process is
repeated until bedrock is confirmed (permanent piles) or the required
depth has been achieved (template piles), however it is possible that
template piles may be fully installed without encountering bedrock.
As each pile segment is installed, WP&YR would splice segments to
increase the length of the pile and continue with the pile
installation. Splicing pipe pile involves welding pipe pile end to end
with a complete joint penetration weld. On average, splicing is
anticipated to require three to five days to complete per pile. For
permanent piles, once bedrock is confirmed and all segments are welded
together, a smaller 8-inch drill would be used to drill a rock anchor
hole into bedrock 50 ft past the pile tip. The 8-inch hole for the rock
anchor is drilled beneath the pile tip from within the hollow pipe
pile. A steel bar would be grouted into this hole. Once the grout sets,
a jack would be applied to the top of the bar and the rock anchor would
be locked off to plates at the top of the pile. After the permanent
piles are installed, temporary piles would be removed.
WP&YR estimates drilling and vibratory hammering would occur for a
maximum of 10 hours per day (although the amount of time within that 10
hour window dedicated to each method cannot be determined at this time
as it is dependent upon substrate conditions) and total number of
impact pile driving strikes would not exceed 2,000 per day. WP&YR
estimates that it would take 8 hours to install and remove one template
pile and 28.1 hours (over the course of multiple days) to install one
permanent pile (additional details can be found in section 2 of WP&YR's
application).
After all dolphin piles are installed, a prefabricated steel
dolphin cap would be set on top of the piles and welded to the cap. The
project also involves modifications to an existing dolphin cap and
installation of two catwalks; however, this work does not include in-
water work and is not anticipated to take marine mammals. All barges,
cranes, equipment, personnel, temporary structures, unused materials,
etc. would be removed from the site upon project completion.
[[Page 64544]]
WP&YR anticipates all in-water construction would occur between
February 1, 2019 and April 30, 2019 (89 days) with mobilization
occurring December through January, 2019 and above water work and
demobilization occurring April through May, 2019. Multiple or all
installation methods of template and permanent piles may occur on the
same day, but would not occur at the same time. Work may occur seven
days per week.
Proposed mitigation, monitoring, and reporting measures are
described in detail later in this document (please see Proposed
Mitigation and Proposed Monitoring and Reporting).
Description of Marine Mammals in the Area of Specified Activities
Sections 3 and 4 of the application summarize available information
regarding status and trends, distribution and habitat preferences, and
behavior and life history, of the potentially affected species.
Additional information regarding population trends and threats may be
found in NMFS' Stock Assessment Reports (SAR; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species
(e.g., physical and behavioral descriptions) may be found on NMFS'
website (https://www.fisheries.noaa.gov/find-species).
Table 2 lists all species with expected potential for occurrence in
the Taiya Inlet and larger Lynn Canal and summarizes information
related to the population or stock, including regulatory status under
the MMPA and ESA and potential biological removal (PBR), where known.
For taxonomy, we follow Committee on Taxonomy (2017). PBR is defined by
the MMPA as the maximum number of animals, not including natural
mortalities, that may be removed from a marine mammal stock while
allowing that stock to reach or maintain its optimum sustainable
population (as described in NMFS' SARs). While no mortality is
anticipated or authorized here, PBR and annual serious injury and
mortality from anthropogenic sources are included here as gross
indicators of the status of the species and other threats.
Marine mammal abundance estimates presented in this document
represent the total number of individuals that make up a given stock or
the total number estimated within a particular study or survey area.
NMFS' stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprises that stock. For some species, this geographic area may extend
beyond U.S. waters. All managed stocks in this region are assessed in
NMFS' U.S. Alaska SARs (e.g., Muto et al. 2018). All values presented
in Table 2 are the most recent available at the time of publication and
are available in the 2017 SARs (Muto et al. 2018) and draft 2018 SARs
(available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/draft-marine-mammal-stock-assessment-reports).
Table 2--Marine Mammals Potentially Present Within Taiya Inlet During the Specified Activity
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ESA/MMPA status; Stock abundance (CV,
Common name Scientific name Stock strategic (Y/N) Nmin, most recent PBR Annual M/
\1\ abundance survey) \2\ SI \3\
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Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
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Family Eschrichtiidae:
Gray whale...................... Eschrichtius robustus.. Eastern North Pacific.. -, -, N 26,960 (0.05, 25,849, 801 138
2016).
Family Balaenidae:
Humpback whale.................. Megaptera novaeangliae. Central North Pacific.. -, -, Y 10,103 (0.3, 7,890, 83 25
2006).
Minke Whale..................... Balaenoptera Alaska................. -, -, N N/A................... UND 0
acutorostrata.
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Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
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Family Physeteridae:
Sperm whale......................... Physeter macrocephalus. North Pacific.......... E, D, Y N/A (N/A, N/A, 2015).. UND 4.4
Family Delphinidae:
Killer whale.................... Orcinus orca........... Alaska Resident........ -, -, N 2,347 (N/A, 2,347, 24 1
2012) \4\.
Northern Resident -, -, N 261 (N/A, 261, 2011) 1.96 0
\4\.
Gulf of Alaska, -, -, N 587 (N/A, 587, 2012) 5.87 1
Aleutian Islands, \4\.
Bering Sea Transient
West Coast Transient -, -, N 243 (N/A, 243, 2009) 2.4 0
\4\.
Pacific White-Sided Dolphin..... Lagenorhynchus North Pacific.......... -, -, N 26,880 (N/A, N/A, UND 0
obliquidens. 1990).
Family Phocoenidae (porpoises):
Harbor porpoise................. Phocoena phocoena...... Southeast Alaska....... -, -, Y 975 (0.12-0.14, 897, 8.9 34
2012) \5\.
Dall's porpoise................. Phocoenoides dalli..... Alaska................. -, -, N 83,400 (0.097, N/A, UND 38
1991).
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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 U.S............ E, D, Y 54,267 (N/A, 54,267, 326 252
2017).
Eastern U.S T, D, Y................ 41,638 (N/A, 2498.................. 108
41,638, 2015)
Family Phocidae (earless seals):
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Harbor seal..................... Phoca vitulina Lynn Canal/Stephens -, -, N 9,478 (N/A, 8,605, 155 50
richardii. Passage. 2011).
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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: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments assessments. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable (N/A).
\3\ These values, found in NMFS' 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\ N is based on counts of individual animals identified from photo-identification catalogs.
\5\ In the SAR for harbor porpoise, NMFS identified population estimates and PBR for porpoises within inland southeast Alaska waters (these abundance
estimates have not been corrected for g(0); therefore, they are likely conservative).
All species that could potentially occur in the proposed survey
areas are included in Table 2. However, the temporal and/or spatial
occurrence of the Pacific white-sided dolphin (Lagenorhynchus
obliquidens), gray whale (Eschrichtius robustus), and sperm whale
(Physeter macrocephalus) are such that take is not expected to occur,
and they are not discussed further beyond the explanation provided
here. The range of Pacific white-sided dolphin is suggested to overlap
with Lynn Canal (Muto et al. 2018), but no sightings have been
documented in the project area (Dahlheim et al. 2009; K. Gross, Never
Monday Charters, personal communication; R. Ford, Taiya Inlet Watershed
Council, personal communication reported in MOS 2016). Gray whale
sightings in this northern portion of Southeast Alaska are very rare;
there have only been eight sightings since 1997 (J. Neilson, National
Park Service, personal communication reported in MOS 2016). None of
these observations occurred in the Taiya Inlet/Lynn Canal. Tagged sperm
whales have been tracked within the Gulf of Alaska, with one whale
tracked up Lynn Canal during October 2014 (SEASWAP 2017). Tagging
studies primarily show that sperm whales use the deep water slope
habitat extensively for foraging (Mathias et al. 2012). This species
prefers deeper waters, and are unlikely to occur in Taiya Inlet.
WP&YR requested take for seven marine mammal species documented in
the waters of the Taiya Inlet/Lynn Canal (Dahlheim et al. 2009; Muto et
al. 2018). One of the species, the harbor seal, is known to regularly
occur near the project site year round; however the closest seasonal
haulout site is three miles (4.8 km) from the project area and not
within the Level B harassment ensonified area (see Estimated Take).
Moderate to high abundances of Steller sea lions are also known to
seasonally occupy the inlet, with the closest seasonal haulout located
11 miles (18 km) from the project site. Several humpback whales have
been observed within Taiya Inlet, sometimes close to Skagway, during
non-winter months. The remaining four species (harbor porpoise, Dall's
porpoise, killer whale, and minke whale) may occur in Taiya Inlet/Lynn
Canal, but less frequently and farther from Skagway Harbor and the
project site. Information on presence and distribution in the WP&YR
project area can be found in the
Habitat
No Biologically Important Areas (BIAs) or ESA-designated critical
habitat overlap with the project area, however there is seasonally
important foraging habitat for some species of marine mammal which
overlap spatially and temporally with proposed project activities. The
annual eulachon run (which occurs for approximately three to four weeks
during April through May) in Lynn Canal is important to all marine
mammals (particularly Steller sea lions, and harbor seals, and humpback
whales) for seasonal foraging and many species travel into Taiya Inlet
to forage on this prey.
Cetaceans
Humpback Whale
The humpback whale is distributed worldwide in all ocean basins. In
winter, most humpback whales are found in the subtropical and tropical
waters of the Northern and Southern Hemispheres, and then migrate to
high latitudes in the summer to feed. The historic summer feeding range
of humpback whales in the North Pacific encompassed coastal and inland
waters around the Pacific Rim from Point Conception, California, north
to the Gulf of Alaska and the Bering Sea, and west along the Aleutian
Islands to the Kamchatka Peninsula and into the Sea of Okhotsk and
north of the Bering Strait (Johnson and Wolman 1984).
There are currently three MMPA-designated stocks of humpback whales
in the North Pacific: (1) The California/Oregon/Washington stock,
consisting of winter/spring populations in coastal Central America and
coastal Mexico which migrate to the coast of California to southern
British Columbia in summer/fall (Calambokidis et al. 1989; Steiger et
al. 1991; Calambokidis et al. 1993); (2) the Central North Pacific
stock, consisting of winter/spring populations of the Hawaiian Islands
which migrate primarily to northern British Columbia/Southeast Alaska,
the Gulf of Alaska, and the Bering Sea/Aleutian Islands (Perry et al.
1990; Calambokidis et al. 1997); and (3) the Western North Pacific
stock, consisting of winter/spring populations off Asia which migrate
primarily to Russia and the Bering Sea/Aleutian Islands. The Central
North Pacific stock is the only stock that is found near the project
area.
On September 8, 2016, NMFS published a final decision changing the
status of humpback whales under the Endangered Species Act (ESA) (81 FR
62259), effective October 11, 2016. Previously, humpback whales were
listed under the ESA as an endangered species worldwide. In the 2016
decision, NMFS recognized the existence of 14 distinct population
segments (DPSs), classified four of those as endangered and one as
threatened, and determined that the remaining nine DPSs do not warrant
protection under the ESA. Whales occurring in the project area would
primarily include individuals from the delisted Hawaii DPS (93.9
percent probability), but could also include individuals from the
threatened Mexico DPS (6.1 percent probability) (Wade et al. 2016).
Humpback whales are found throughout southeast Alaska in a variety
of marine environments, including
[[Page 64546]]
open-ocean, near-shore waters, and areas with 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 occurs in southeast Alaska year-round (Straley
1990). Dahlheim et al. (2009) observed humpback whales throughout all
major waterways in southeast Alaska with concentrations of whales
consistently observed in Icy Strait, Lynn Canal, Stephens Passage,
Chatham Strait, and Frederick Sound. Mean group size varied among
season with group sizes of 1.38, 1.65, and 1.95 in spring, summer, and
fall respectively.
Subsistence hunters in Alaska are not authorized to take Central
North Pacific stock humpback whales and no takes were reported from
2012-2016 (Muto et al. 2018). Threats to the Central North Pacific
stock include changes in prey distribution due to climate change,
entanglement in fishing gear, ship strike, and anthropogenic sound,
however the Central North Pacific stock is increasing (Muto et al.
2018).
Minke Whale
Minke whales are found throughout the northern hemisphere in polar,
temperate, and tropical waters. In the North Pacific, minke whales
occur from the Bering and Chukchi seas south to near the Equator
(Leatherwood et al. 1982). Minke whales are generally found in coastal
waters shallower than 200 m and are usually observed solitary or in
small groups of two to three whales (Zerbini et al. 2006; Zerbini et
al. 2006). In Alaska, there is only one stock of minke whales and
seasonal movements are associated with feeding areas that are generally
located at the edge of the pack ice (NMFS 2014).
Although no comprehensive abundance estimate is available for the
Alaska stock of minke whales, recent surveys provide estimates for
portions of the stock's range. A 2010 survey conducted on the eastern
Bering Sea shelf produced a provisional abundance estimate of 2,020 (CV
= 0.73) whales (Friday et al. 2013). This estimate is considered
provisional because it has not been corrected for animals missed on the
trackline, animals submerged when the ship passed, or responsive
movement. Additionally, line-transect surveys were conducted in shelf
and nearshore waters (within 30-45 nautical miles of land) in 2001-2003
between the Kenai Peninsula (150[deg] W) and Amchitka Pass (178[deg]
W). Minke whale abundance was estimated to be 1,233 (CV = 0.34) for
this area (also not corrected for animals missed on the trackline)
(Zerbini et al. 2006). The majority of the sightings were in the
Aleutian Islands, rather than in the Gulf of Alaska, and in water
shallower than 200 m. These estimates cannot be used as an estimate of
the entire Alaska stock of minke whales because only a portion of the
stock's range was surveyed.
Surveys in southeast Alaska have consistently identified
individuals throughout inland waters in low numbers, however none were
observed in Taiya Inlet or Lynn Canal (Dahlheim et al. 2009). As few
minke whales were observed during recent offshore Gulf of Alaska
surveys for cetaceans in 2009, 2013, and 2015, a population estimate
for minke whales in this area cannot be determined (Rone et al. 2017).
There are no data available to determine trends in minke whale
abundance in Alaska waters. Subsistence takes of minke whales in Alaska
is rare, with the last known catch occurring in 1989. Although no
incidents of human-related serious injury and mortality were recorded
for Alaska stock minke whales between 2012 and 2016, threats to the
population include entanglement in fishing gear, ship strikes, and
anthropogenic sound, as well as changes in prey distribution due to
climate change (Muto et al. 2018).
Killer Whale
Killer whales have been observed in all oceans and seas of the
world, but the highest densities occur in colder and more productive
waters found at high latitudes. Killer whales are found throughout the
North Pacific, and occur along the entire Alaska coast, in British
Columbia and Washington inland waterways, and along the outer coasts of
Washington, Oregon, and California (Muto et al. 2018). Based on data
regarding association patterns, acoustics, movements, and genetic
differences, eight killer whale stocks are now recognized in the
Pacific Ocean: (1) The Alaska Resident stock; (2) the Northern Resident
stock; (3) the Southern Resident stock; (4) the Gulf of Alaska,
Aleutian Islands, and Bering Sea Transient stock; (5) the AT1 Transient
stock; (6) the West Coast Transient stock; and (7) the Offshore stock,
and (8) the Hawaii stock. Only the Alaska Resident, Northern Resident,
Gulf of Alaska, Aleutian Islands, and Bering Sea Transient, and West
Coast Transient stocks are considered in this analysis because other
stocks occur outside the geographic area under consideration. Any of
these four stocks could be seen in the action area; however, the Alaska
and Northern Resident stocks are most likely to overlap with the
project area (Muto et al. 2018).
The Alaska Resident stock is found from southeastern Alaska to the
Aleutian Islands and Bering Sea. Intermixing of Alaska Residents have
been documented among the three areas, at least as far west as the
eastern Aleutian Islands. The Northern Resident stock occurs from
Washington State through part of southeastern Alaska. The Northern
Resident stock is a transboundary stock, and includes killer whales
that frequent British Columbia, Canada and southeastern Alaska
(Dahlheim et al. 1997; Ford et al. 2000). The Gulf of Alaska, Aleutian
Islands, and Bering Sea Transient stock occurs mainly from Prince
William Sound through the Aleutian Islands and Bering Sea. The West
Coast Transient stock includes animals that occur in California,
Oregon, Washington, British Columbia and southeastern Alaska.
Transient killer whales occur in smaller, less matrilineal
groupings than resident killer whales. They are also more likely to
rely on stealth tactics when foraging, making fewer and less
conspicuous calls, and edging along shorelines and around headlands in
order to hunt their prey, including, Steller sea lions, harbor seals,
and smaller cetaceans, in highly coordinated attacks (Barrett-Lennard
et al. 2011). Residents often travel in much larger and closer knit
groups within which they share any fish they catch.
Resident and transient killer whales have been documented in the
middle to lower reaches of Lynn Canal, but not within the upper reaches
or in Taiya Inlet (Dahlheim et al. 2009). Dahlheim et al. (2009)
frequently observed two resident pods identified as AF and AG pods
(Alaska Resident stock) throughout Icy Strait, Lynn Canal, Stephens
Passage, Frederick Sound and upper Chatham Strait. The seasonality of
resident killer whales could not be investigated statistically due to
low encounter rates and mean group size of resident whales did not vary
significantly among seasons and ranged from 19 to 33 individuals
(Dahlheim et al. 2009).
Dahlheim et al. (2009) observed transient killer whales in all
major waterways, including Lynn Canal, in open-strait environments,
near-shore waters, protected bays and inlets, and in ice-laden waters
near tidewater glaciers. The transient killer whale mean group size
also did not vary with season and ranged from four to six individuals
in Southeast Alaska (Dahlheim et al. 2009). Transient killer whale
numbers were highest in summer, with lower numbers observed in spring
and fall.
[[Page 64547]]
No reliable data on trends in population abundance for the entire
Alaska Resident, Gulf of Alaska, Aleutian Islands, and Bering Sea
Transient, and West Coast Transient stocks of killer whales are
unavailable (Muto et al. 2018). The Northern Resident stock is
increasing with an average 2.1 percent increase over a 36 year time
period (Ellis et al. 2011). There are no reports of subsistence harvest
of killer whales in Alaska, however other threats to the stocks include
interactions with fisheries, vessel collisions, and decreases in prey
abundance (Muto et al. 2018).
Harbor Porpoise
The harbor porpoise inhabits temporal, subarctic, and arctic
waters. In the eastern North Pacific, harbor porpoises range from Point
Barrow, Alaska, to Point Conception, California. While harbor porpoise
primarily frequent coastal waters and occur most frequently in waters
less than 100 m deep (Hobbs and Waite 2010), they may occasionally be
found in deeper offshore waters. Within the inland waters of Southeast
Alaska, harbor porpoise distribution is clumped, with greatest
densities observed in the Glacier Bay/Icy Strait region, and near
Zarembo and Wrangell Islands and the adjacent waters of Sumner Strait
(Allen and Angliss 2014). Group sizes were on average between 1.37-1.59
animals (less than 2) (Dahlheim et al. 2009; 2015).
In Alaska, harbor porpoises are currently divided into three
stocks, based primarily on geography. These are (1) the Southeast
Alaska stock--occurring from the northern border of British Columbia to
Cape Suckling, Alaska, (2) the Gulf of Alaska stock--occurring from
Cape Suckling to Unimak Pass, and (3) the Bering Sea stock--occurring
throughout the Aleutian Islands and all waters north of Unimak Pass
(Allen and Angliss 2014). Only the Southeast Alaska stock is considered
in this analysis because it is the only stock found in the project
area.
No reports of subsistence harvest of harbor porpoises from the
Southeast Alaska stock have been reported since the early 1900s
(Shelden et al. 2014).The total estimated annual level of human-caused
mortality and serious injury for Southeast Alaska stock (n = 34)
exceeds the calculated PBR of 8.9 porpoises. However because the
calculated PBR is based on surveys from 2010-2012 in only a portion of
the stock's range (the inside water of southeast Alaska), PBR is likely
biased low for the entire stock (Muto et al. 2018). Population trends
and status of this stock relative to its Optimum Sustainable Population
are currently unknown.
Dall's Porpoise
Dall's porpoise are widely distributed across the entire North
Pacific Ocean. They are found over the continental shelf adjacent to
the slope and over deep (greater than 2,500 m) oceanic waters and have
been sighted throughout the North Pacific as far north as 65[deg] N
(Hall 1979; Buckland et al. 1993). The only apparent distribution gaps
in Alaska waters are upper Cook Inlet and the shallow eastern flats of
the Bering Sea. They are present during all months of the year in much
of the eastern North Pacific, although they may make seasonal onshore-
offshore movements along the west coast of the continental United
States and winter movements out of areas with ice (Hall 1979;
Leatherwood and Fielding 1974; Loeb 1972).
Currently one stock of Dall's porpoise is recognized in Alaskan
waters (Muto et al. 2018). Dahlheim et al. (2009) observed Dall's
porpoise throughout Southeast Alaska, but only observed Dall's porpoise
in Lynn Canal as far north as Haines, Alaska, about 15 miles south of
Skagway. Infrequent observations (three to six) of Dall's porpoise have
been observed in Taiya Inlet during the early spring and late fall,
however they have not been observed near the project site near the
Skagway waterfront (K. Gross, Never Monday Charters, personal
communication reported in MOS 2016). At present, there is no reliable
information on trends in abundance for the Alaska stock of Dall's
porpoise (Muto et al. 2018). There are no subsistence uses of this
species (Muto et al. 2018), however Dall's porpoise are vulnerable to
fisheries-related entanglement and injury and to physical modifications
of nearshore habitats resulting from urban and industrial development
(including waste management and nonpoint source runoff), and noise
(Linnenschmidt et al. 2013).
Pinnipeds
Steller Sea Lion
The Steller sea lion is the largest of the eared seals (otariids),
ranging along the North Pacific Rim from northern Japan to California,
with centers of abundance and distribution in the Gulf of Alaska and
Aleutian Islands. Steller sea lions use terrestrial haulout sites to
rest and take refuge. They also gather on well-defined, traditionally
used rookeries to pup and breed. These habitats are typically gravel,
rocky, or sand beaches; ledges; or rocky reefs (Muto et al. 2018).
Steller sea lion populations that primarily occur west of 144[deg] W
(Cape Suckling, Alaska) comprise the western Distinct Population
Segment (wDPS) or Western U.S. stock, while all others comprise the
eastern DPS (eDPS) or Eastern U.S. stock; however, there is regular
movement of both DPSs across this boundary (Muto et al. 2018). Both of
these populations may occur in the action area, however in Lynn Canal/
Taiya Inlet Steller sea lions are most likely part of the eDPS/Eastern
U.S. stock. Based on the percent of branded animals at Gran Point it is
estimated that 2 percent of the sea lions in the project area are
potentially from the wDPS/Eastern U.S. stock (personal communication,
L. Jemison Alaska Department of Fish and Game, 2017). Steller sea lions
were listed as threatened range-wide under the ESA on 26 November 1990
(55 FR 49204). Steller sea lions were subsequently partitioned into the
western and eastern DPSs in 1997, with the wDPS being listed as
endangered under the ESA and the eDPS remaining classified as
threatened (62 FR 24345) until it was delisted in November 2013. In
August 1993, NMFS published a final rule designating critical habitat
for the Steller sea lion as a 20-nautical mile buffer around all major
haul-outs and rookeries, as well as associated terrestrial, air and
aquatic zones, and three large offshore foraging areas (50 CFR
226.202). There is no Steller sea lion critical habitat located in the
action area.
Gran Point, which is located 24 mi (38 km) south of the project
area, is the closest year-round Steller sea lion haulout. However,
during the spring eulachon run, a seasonal haulout site is located on
Taiya Point at the southern tip of Taiya Inlet, approximately 11 mi (18
km) from the project site. Twenty-five to 40 sea lions are estimated to
use this haulout for about three weeks during spring run, during which
they frequently are observed in the inlet. The eulachon run (which
occurs for approximately three to four weeks during mid-March through
May) in Lynn Canal is important to Steller sea lions for seasonal
foraging. These spawning aggregations of forage fish provide densely
aggregated, high-energy prey for Steller sea lions (and harbor seals)
for brief time periods and influence haulout use (Sigler et al. 2004;
Womble et al. 2005; Womble and Sigler 2006). The pre-spawning
aggregations and spawning season for many forage fish species occur
between March and
[[Page 64548]]
May in Southeast Alaska just prior to the breeding season of sea lions
(Pitcher et al. 2001; Womble and Sigler 2006). After May, Steller sea
lion presence in the project action area declines. During surveys
conducted in 2002 and 2003, Womble et al. (2005) observed a maximum of
approximately 400 Steller sea lions in the water at the mouth of the
Taiya River feeding on eulachon in 2003, but observed very few in the
same area in 2002. Steller sea lions have also been observed in Lutak
Inlet, a foraging site closer to both Taiya Point and Gran Point
haulouts.
Steller sea lions are included in Alaska subsistence harvests. The
mean annual subsistence take of Western U.S. Steller sea lions was 203
from 2004-2016, and the mean annual take of Eastern U.S. Steller sea
lions was 11 from 2005-2008 and 2012 (Muto et al. 2018). Entanglements
in fishing gear and marine debris, and interactions with fishing gear
are sources of mortality and serious injury for Steller sea lions. The
Eastern U.S. stock is increasing with models indicating the rate of
increase as 4.76 percent per year based on pup counts and 2.84 percent
per year based on non-pup counts (Muto et al. 2018). Pup and non-pup
counts of Western U.S. stock Steller sea lions in Alaska have increased
1.78 percent per year and 2.14 per year respectively between 2002 and
2017.
Harbor Seal
Harbor seals range from Baja California north along the west coasts
of Washington, Oregon, California, British Columbia, and Southeast
Alaska; west through the Gulf of Alaska, Prince William Sound, and the
Aleutian Islands; and north in the Bering Sea to Cape Newenham and the
Pribilof Islands (Muto et al. 2018). They haul out on rocks, reefs,
beaches, and drifting glacial ice, and feed in marine, estuarine, and
occasionally fresh waters. Harbor seals generally are nonmigratory,
with local movements associated with such factors as tides, weather,
season, food availability, and reproduction (Scheffer and Slipp 1944;
Fisher 1952; Bigg 1969, 1981; Hastings et al. 2004).
Harbor seals in Alaska are partitioned into 12 separate stocks
based largely on genetic structure: (1) The Aleutian Islands stock, (2)
the Pribilof Islands stock, (3) the Bristol Bay stock, (4) the North
Kodiak stock, (5) the South Kodiak stock, (6) the Prince William Sound
stock, (7) the Cook Inlet/Shelikof stock, (8) the Glacier Bay/Icy
Strait stock, (9) the Lynn Canal/Stephens Passage stock, (10) the
Sitka/Chatham stock, (11) the Dixon/Cape Decision stock, and (12) the
Clarence Strait stock. Only the Lynn Canal/Stephens Passage stock is
considered in this analysis. The stock range includes north along the
east and north coast of Admiralty Island from the north end of
Kupreanof Island through Lynn Canal, including Taku Inlet, Tracy Arm,
and Endicott Arm (Muto et al. 2018). The most current (2007-2011)
estimate of the population trend for the stock is -176 seals per year,
with a probability that the stock is decreasing of 0.71 (Muto et al.
2018).
Harbor seals are included in subsistence harvests. Annual harvests
from the Lynn Canal/Stephens Passage in 2011 and 2012 were 50 animals
each year, which is higher than previous estimates of 30 animals, on
average, per year from 2004-2008 (Muto et al. 2018). Entanglement in
fishing gear is also a large contributor to their annual human-caused
serious injury/mortality.
Additional information on the biology and local distribution of
these species can be found in the NMFS Marine Mammal Stock Assessment
Reports, which may be found at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments.
Marine Mammal Hearing
Hearing is the most important sensory modality for marine mammals
underwater, and exposure to anthropogenic sound can have deleterious
effects. To appropriately assess the potential effects of exposure to
sound, it is necessary to understand the frequency ranges marine
mammals are able to hear. Current data indicate that not all marine
mammal species have equal hearing capabilities (e.g., Richardson et al.
1995; Wartzok and Ketten 1999; Au and Hastings 2008). To reflect this,
Southall et al. (2007) recommended that marine mammals be divided into
functional hearing groups based on directly measured or estimated
hearing ranges on the basis of available behavioral response data,
audiograms derived using auditory evoked potential techniques,
anatomical modeling, and other data. Note that no direct measurements
of hearing ability have been successfully completed for mysticetes
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described
generalized hearing ranges for these marine mammal hearing groups.
Generalized hearing ranges were chosen based on the approximately 65 dB
threshold from the normalized composite audiograms, with the exception
for lower limits for low-frequency cetaceans where the lower bound was
deemed to be biologically implausible and the lower bound from Southall
et al. (2007) retained. The functional groups and the associated
frequencies are indicated below (note that these frequency ranges
correspond to the range for the composite group, with the entire range
not necessarily reflecting the capabilities of every species within
that group):
Low-frequency cetaceans (mysticetes): Generalized hearing
is estimated to occur between approximately 7 Hz and 35 kHz;
Mid-frequency cetaceans (larger toothed whales, beaked
whales, and most delphinids): Generalized hearing is estimated to occur
between approximately 150 Hz and 160 kHz;
High-frequency cetaceans (porpoises, river dolphins, and
members of the genera Kogia and Cephalorhynchus; including two members
of the genus Lagenorhynchus, on the basis of recent echolocation data
and genetic data): Generalized hearing is estimated to occur between
approximately 275 Hz and 160 kHz.
Pinnipeds in water; Phocidae (true seals): Generalized
hearing is estimated to occur between approximately 50 Hz to 86 kHz;
Pinnipeds in water; Otariidae (eared seals): Generalized
hearing is estimated to occur between 60 Hz and 39 kHz.
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al. 2006; Kastelein et al. 2009; Reichmuth and Holt
2013).
For more detail concerning these groups and associated frequency
ranges, please see NMFS (2018) for a review of available information.
Seven marine mammal species (five cetacean and two pinniped (one
otariid and one phocid) species) have the reasonable potential to co-
occur with the proposed activities. Please refer to Table 2. Of the
cetacean species that may be present, two are classified as low-
frequency cetaceans (i.e., all mysticete species), one is classified as
a mid-frequency cetacean (i.e., all delphinid and ziphiid species and
the sperm whale), and two are classified as high-frequency cetaceans
(i.e., harbor porpoise and Kogia spp.).
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
This section includes a summary and discussion of the ways that
components of the specified activity may impact marine mammals and
their habitat. The Estimated Take by Incidental Harassment section
later in this document includes a quantitative
[[Page 64549]]
analysis of the number of individuals that are expected to be taken by
this activity. The Negligible Impact Analysis and Determination section
considers the content of this section, the Estimated Take by Incidental
Harassment section, and the Proposed Mitigation section, to draw
conclusions regarding the likely impacts of these activities on the
reproductive success or survivorship of individuals and how those
impacts on individuals are likely to impact marine mammal species or
stocks.
Description of Sound Sources
The marine soundscape is comprised of both ambient and
anthropogenic sounds. Ambient sound is defined as the all-encompassing
sound in a given place and is usually a composite of sound from many
sources both near and far (ANSI 1994). 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 impact pile driving, vibratory pile driving and removal, 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 2018). Non-impulsive sounds (e.g.
aircraft, machinery operations such as drilling or dredging, vibratory
pile driving, and active sonar systems) can be broadband, narrowband or
tonal, brief or prolonged (continuous or intermittent), and typically
do not have the high peak sound pressure with raid rise/decay time that
impulsive sounds do (ANSI 1995; NIOSH 1998; NMFS 2018). The distinction
between these two sound types is important because they have differing
potential to cause physical effects, particularly with regard to
hearing (e.g., Ward 1997 in Southall et al. 2007).
Two types of pile hammers would be used on this project: Impact and
vibratory. Impact hammers operate by repeatedly dropping a heavy piston
onto a pile to drive the pile into the substrate. 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 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).
Drilling would be conducted using a down-the-hole drill inserted
through the hollow steel piles. A down-the-hole drill is a drill bit
that drills through the bedrock using a pulse mechanism that functions
at the bottom of the hole. This pulsing bit breaks up rock to allow
removal of debris and insertion of the pile. The head extends so that
the drilling takes place below the pile. The pulsing sounds produced by
the down-the-hole drilling method are continuous, however this method
likely increases sound attenuation because the noise is primarily
contained within the steel pile and below ground rather than impact
hammer driving methods which occur at the top of the pile (R&M 2016).
The likely or possible impacts of WP&YR'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 the equipment and personnel; however, any impacts to marine
mammals are expected to primarily be acoustic in nature. Acoustic
stressors include effects of heavy equipment operation during pile
installation and removal and drilling.
Acoustic Impacts
The introduction of anthropogenic noise into the aquatic
environment from pile driving and removal and down-the-hole drilling is
the primary means by which marine mammals may be harassed from WP&YR'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 and 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 and 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 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
[[Page 64550]]
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 animal uses sound within the frequency
band of the signal; e.g., Kastelein et al. 2014b), 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)--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 (2016),
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 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 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.
Currently, TTS data only exist for four species of cetaceans
(bottlenose dolphin (Tursiops truncatus), beluga whale (Delphinapterus
leucas), harbor porpoise, and Yangtze finless porpoise (Neophocoena
asiaeorientalis)) and five species of pinnipeds exposed to a limited
number of sound sources (i.e., mostly tones and octave-band noise) in
laboratory settings (Finneran 2015). TTS was not observed in trained
spotted (Phoca largha) and ringed (Pusa hispida) seals exposed to
impulsive noise at levels matching previous predictions of TTS onset
(Reichmuth et al. 2016). In general, harbor seals and harbor porpoises
have a lower TTS onset than other measured pinniped or cetacean species
(Finneran 2015). Additionally, the existing marine mammal TTS data come
from a limited number of individuals within these species. No data are
available on noise-induced hearing loss for mysticetes. For summaries
of data on TTS in marine mammals or for further discussion of TTS onset
thresholds, please see Southall et al. (2007), Finneran and Jenkins
(2012), Finneran (2015), and Table 5 in NMFS (2018). Installing piles
requires a combination of impact pile driving, vibratory pile driving,
and down-the-hole drilling. For the project, these activities would not
occur at the same time and there would likely be pauses in activities
producing the sound during each day. Given these pauses and that many
marine mammals are likely moving through the action area and not
remaining for extended periods of time, the potential for TS declines.
Behavioral Harassment--Exposure to noise from pile driving and
removal and drilling also has the potential to behaviorally disturb
marine mammals. Available studies show wide variation in response to
underwater sound; therefore, it is difficult to predict specifically
how any given sound in a particular instance might affect marine
mammals perceiving the signal. If a marine mammal does react briefly to
an underwater sound by changing its behavior or moving a small
distance, the impacts of the change are unlikely to be significant to
the individual, let alone the stock or population. However, if a sound
source displaces marine mammals from an important feeding or breeding
area for a prolonged period, impacts on individuals and populations
could be significant (e.g., Lusseau and Bejder 2007; Weilgart 2007; NRC
2005).
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; Archer et al. 2010). 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,
[[Page 64551]]
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.
In 2016, the Alaska Department of Transportation and Public
Facilities (ADOT&PF) documented observations of marine mammals during
construction activities (i.e., pile driving and down-hole drilling) at
the Kodiak Ferry Dock (see 80 FR 60636 for Final IHA Federal Register
notice). In the marine mammal monitoring report for that project (ABR
2016), 1,281 Steller sea lions were observed within the Level B
disturbance zone during pile driving or drilling (i.e., documented as
Level B harassment take). Of these, 19 individuals demonstrated an
alert behavior, 7 were fleeing, and 19 swam away from the project site.
All other animals (98 percent) were engaged in activities such as
milling, foraging, or fighting and did not change their behavior. In
addition, two sea lions approached within 20 meters of active vibratory
pile driving activities. Three harbor seals were observed within the
disturbance zone during pile driving activities; none of them displayed
disturbance behaviors. Fifteen killer whales and three harbor porpoise
were also observed within the Level B harassment zone during pile
driving. The killer whales were travelling or milling while all harbor
porpoises were travelling. No signs of disturbance were noted for
either of these species. Given the similarities in activities and
habitat and the fact the same species are involved, we expect similar
behavioral responses of marine mammals to the specified activity. That
is, disturbance, if any, is likely to be temporary and localized (e.g.,
small area movements). Monitoring reports from other recent pile
driving and down-the-hole drilling projects in Alaska have observed
similar behaviors (for example, the Biorka Island Dock Replacement
Project).
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.
Skagway Harbor contains an active port of call for cruise ships and
hosts numerous recreational and commercial vessels; therefore,
background sound levels in the harbor are already elevated.
Airborne Acoustic Effects--Pinnipeds that occur near the project
site could be exposed to airborne sounds associated with pile driving
and removal and down-the-hole drilling that have the potential to cause
behavioral harassment, depending on their distance from pile driving
activities. Cetaceans are not expected to be exposed to airborne sounds
that would result in harassment as defined under the MMPA.
Airborne noise would primarily be an issue for pinnipeds that are
swimming or hauled out near the project site within the range of noise
levels elevated above the acoustic criteria. We recognize that
pinnipeds in the water could be exposed to airborne sound that may
result in behavioral harassment when looking with their heads above
water. Most likely, airborne sound would cause behavioral responses
similar to those discussed above in relation to underwater sound. For
instance, anthropogenic sound could cause hauled-out pinnipeds to
exhibit changes in their normal behavior, such as reduction in
vocalizations, or cause them to temporarily abandon the area and move
further from the source. However, these animals would previously have
been `taken' because of exposure to underwater sound above the
behavioral harassment thresholds, which are in all cases larger than
those associated with airborne sound. Thus, the behavioral harassment
of these animals is already accounted for in these estimates of
potential take. Therefore, we do not believe that authorization of
incidental take resulting from airborne sound for pinnipeds is
warranted, and airborne sound is not discussed further here.
Marine Mammal Habitat Effects
WP&YR construction activities at the Railroad Dock could have
localized, temporary impacts on marine mammal habitat and their prey by
increasing in-water sound pressure levels and slightly decreasing water
quality. 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 impact
pile driving, elevated levels of underwater noise would ensonify Taiya
Inlet where both fish and mammals occur and could affect foraging
success.
Construction activities are of short duration and would likely have
temporary impacts on marine mammal habitat through increases in
underwater and airborne sound. These sounds would not be detectable at
the nearest known Steller sea lion haulouts, and all known harbor seal
haulouts are well beyond the maximum distance of predicted in-air
acoustical disturbance.
In-water pile driving, pile removal, and drilling activities would
also cause short-term effects on water quality due to increased
turbidity. Local strong currents are anticipated to disburse suspended
sediments produced by project activities at moderate to rapid rates
depending on tidal stage. WP&YR would employ standard construction best
management practices (BMPs; see section 11 and Appendix B in
application), thereby reducing any impacts. Therefore, the impact from
increased turbidity levels is expected to be discountable.
In-Water Construction Effects on Potential Foraging Habitat
The area likely impacted by the project is relatively small
compared to the available habitat in Lynn Canal/Taiya Inlet (e.g., most
of the impacted area is limited to the northern and western portions of
Taiya Inlet) and does not include any BIAs or ESA-designated critical
habitat. Pile installation/removal and drilling may
[[Page 64552]]
temporarily increase turbidity resulting from suspended sediments. Any
increases would be temporary, localized, and minimal. WP&YR must comply
with state water quality standards during these operations by limiting
the extent of turbidity to the immediate project area. In general,
turbidity associated with pile installation is localized to about a 25-
foot radius around the pile (Everitt et al. 1980). Cetaceans are not
expected to be close enough to the project pile driving areas to
experience effects of turbidity, and any pinnipeds would be transiting
the area and could avoid localized areas of turbidity. Therefore, the
impact from increased turbidity levels is expected to be discountable
to marine mammals. Furthermore, pile driving and removal 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 in Lynn Canal/
Taiya Inlet.
The duration of the construction activities is relatively short.
The construction window is for a maximum of 89 days and during each
day, construction activities would only occur during daylight hours.
Impacts to habitat and prey are expected to be minimal based on the
short duration of activities.
In-Water Construction Effects on Potential Prey (Fish)--
Construction activities would produce continuous (i.e., vibratory pile
driving and down-the-hole drilling) and pulsed (i.e. impact driving)
sounds. Fish react to sounds that are especially strong and/or
intermittent low-frequency sounds. Short duration, sharp sounds can
cause overt or subtle changes in fish behavior and local distribution.
Hastings and Popper (2005) identified several studies that suggest fish
may relocate to avoid certain areas of sound energy. Additional studies
have documented effects of pile driving on fish, although several are
based on studies in support of large, multiyear bridge construction
projects (e.g., Scholik and Yan 2001, 2002; Popper and Hastings 2009).
Sound pulses at received levels of 160 dB may cause subtle changes in
fish behavior. SPLs of 180 dB may cause noticeable changes in behavior
(Pearson et al. 1992; Skalski et al. 1992). SPLs of sufficient strength
have been known to cause injury to fish and fish mortality.
The most likely impact to fish from pile driving and drilling
activities at the project area would be temporary behavioral avoidance
of the area. 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. In general, impacts to marine
mammal prey species are expected to be minor and temporary due to the
short timeframe for the project.
Construction activities, in the form of increased turbidity, have
the potential to adversely affect forage fish and juvenile salmonid
outmigratory routes in the project area. Both herring and salmon form a
significant prey base for Steller sea lions, herring is a primary prey
species of humpback whales, and both herring and salmon are components
of the diet of many other marine mammal species that occur in the
project area. Increased turbidity is expected to occur in the immediate
vicinity (on the order of 10 feet 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 and salmon are
expected to be minor or negligible. In addition, best management
practices would be in effect, which would limit the extent of turbidity
to the immediate project area. Finally, exposure to turbid waters from
construction activities is not expected to be different from the
current exposure; fish and marine mammals in the Lynn Canal/Taiya Inlet
region are routinely exposed to substantial levels of suspended
sediment from glacial sources.
In summary, given the short daily duration of sound associated with
individual pile driving and drilling events and the relatively small
areas being affected, pile driving and drilling activities associated
with the proposed action are not likely to have a permanent, adverse
effect on any fish habitat, or populations of fish species. Thus, we
conclude that impacts of the specified activity are not likely to have
more than short-term adverse effects on any prey habitat or populations
of prey species. Further, any impacts to marine mammal habitat are not
expected to result in significant or long-term consequences for
individual marine mammals, or to contribute to adverse impacts on their
populations.
Estimated Take
This section provides an estimate of the number of incidental takes
proposed for authorization through this IHA, which will inform both
NMFS' consideration of ``small numbers'' and the negligible impact
determination.
Harassment is the only type of take expected to result from these
activities. Except with respect to certain activities not pertinent
here, section 3(18) of the MMPA defines ``harassment'' as any act of
pursuit, torment, or annoyance which (i) has the potential to injure a
marine mammal or marine mammal stock in the wild (Level A harassment);
or (ii) has the potential to disturb a marine mammal or marine mammal
stock in the wild by causing disruption of behavioral patterns,
including, but not limited to, migration, breathing, nursing, breeding,
feeding, or sheltering (Level B harassment).
Authorized takes would primarily be by Level B harassment, as use
of the impact and vibratory hammers and down-the-hole drilling 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, primarily for low-frequency cetaceans, high-
frequency cetaceans, and/or phocids because predicted auditory injury
zones are larger than for mid-frequency cetaceans and otariids.
Auditory injury is unlikely to occur for mid-frequency cetaceans and
otariids. The proposed mitigation and monitoring measures are expected
to minimize the severity of such taking to the extent practicable. As
described previously, no mortality is anticipated or proposed to be
authorized for this activity. Below we describe how the take is
estimated.
Generally speaking, we estimate take by considering: (1) Acoustic
thresholds above which NMFS believes the best available science
indicates marine mammals will be behaviorally harassed or incur some
degree of permanent hearing impairment; (2) the area or volume of water
that will be ensonified above these levels in a day; (3) the density or
occurrence of marine mammals within these ensonified areas; and, (4)
and the number of days of activities. We note that while these basic
factors can contribute to a basic calculation to provide an initial
prediction of takes, additional information that can qualitatively
inform take estimates is also sometimes available (e.g., previous
monitoring results or average group size). Below, we describe the
factors considered here in
[[Page 64553]]
more detail and present the proposed take estimate.
Acoustic Thresholds
Using the best available science, NMFS has developed acoustic
thresholds that identify the received level of underwater sound above
which exposed marine mammals would be reasonably expected to be
behaviorally harassed (equated to Level B harassment) or to incur PTS
of some degree (equated to Level A harassment).
Level B Harassment for non-explosive sources--Though significantly
driven by received level, the onset of behavioral disturbance from
anthropogenic noise exposure is also informed to varying degrees by
other factors related to the source (e.g., frequency, predictability,
duty cycle), the environment (e.g., bathymetry), and the receiving
animals (hearing, motivation, experience, demography, behavioral
context) and can be difficult to predict (Southall et al.; 2007,
Ellison et al. 2012). Based on what the available science indicates and
the practical need to use a threshold based on a factor that is both
predictable and measurable for most activities, NMFS uses a generalized
acoustic threshold based on received level to estimate the onset of
behavioral harassment. NMFS predicts that marine mammals are likely to
be behaviorally harassed in a manner we consider Level B harassment
when exposed to underwater anthropogenic noise above received levels of
120 dB re 1 [mu]Pa (rms) for continuous (e.g., vibratory pile-driving,
drilling) and above 160 dB re 1 [mu]Pa (rms) for non-explosive
impulsive (e.g., seismic airguns) or intermittent (e.g., scientific
sonar) sources. WP&YR's proposed activity includes the use of
continuous (vibratory pile driving/removal and drilling) and impulsive
(impact pile driving) sources, and therefore the 120 and 160 dB re 1
[mu]Pa (rms) thresholds are applicable.
Level A harassment for non-explosive sources--NMFS' Technical
Guidance for Assessing the Effects of Anthropogenic Sound on Marine
Mammal Hearing (Version 2.0) (NMFS 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).
WP&YR's proposed activity includes the use of impulsive (impact pile
driving) and non-impulsive (vibratory pile driving/removal and
drilling) sources.
These thresholds are provided in Table 3. The references, analysis,
and methodology used in the development of the thresholds are described
in NMFS 2018 Technical Guidance, which may be accessed at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.
Table 3--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
PTS onset thresholds * (received level)
Hearing group ------------------------------------------------------------------------
Impulsive Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans........... L,0-pk,flat: 219 dB; LE,, LE,, LF,24h: 199 dB.
LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans........... L,0-pk,flat: 230 dB; LE,, LE,, MF,24h: 198 dB.
MF,24h: 185 dB.
High-Frequency (HF) Cetaceans.......... L,0-pk,flat: 202 dB; LE,, HF,24h: 173 dB.
LE,,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater)..... L,0-pk.flat: 218 dB; LE,,PW,24h: 201 dB.
LE,,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater).... L,0-pk,flat: 232 dB; LE,,OW,24h: 219 dB.
LE,,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric thresholds for impulsive sounds: Use whichever results in the largest isopleth for calculating PTS
onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level thresholds
associated with impulsive sounds, these thresholds are recommended for consideration.
Note: Peak sound pressure level (L,0-pk) has a reference value of 1 [micro]Pa, and weighted cumulative sound
exposure level (LE,) has a reference value of 1[micro]Pa\2\s. In this table, thresholds are abbreviated to be
more reflective of International Organization for Standardization standards (ISO 2017). The subscript ``flat''
is being included to indicate peak sound pressure are flat weighted or unweighted within the generalized
hearing range of marine mammals (i.e., 7 Hz to 160 kHz). The subscript associated with cumulative sound
exposure level thresholds indicates the designated marine mammal auditory weighting function (LF, MF, and HF
cetaceans, and PW and OW pinnipeds) and that the recommended accumulation period is 24 hours. The weighted
cumulative sound exposure level thresholds could be exceeded in a multitude of ways (i.e., varying exposure
levels and durations, duty cycle). When possible, it is valuable for action proponents to indicate the
conditions under which these thresholds will be exceeded.
Ensonified Area
Here, we describe operational and environmental parameters of the
activity that will feed into identifying the area ensonified above the
acoustic thresholds, which include 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 down-the-hole drilling). The maximum
(underwater) ensonification area of 17.9 km \2\ due to project
activities is governed by the topography of Taiya Inlet (see Figure 6
in the application). The eastern shoreline of the inlet is acoustically
shadowed due to land located just south of the proposed project site.
Similarly, Yakutania Point and Dyea Point would inhibit transmission of
project sounds from reaching Nahku Bay and the upper inlet at the mouth
of the Taiya River. Additionally, vessel traffic and other commercial
and industrial activities in the project area may contribute to
elevated background noise levels which may mask sounds produced by the
project.
In order to calculate distances to the Level A and Level B
harassment thresholds for piles of various sizes being used in this
project, NMFS used acoustic monitoring data from other locations. Note
that piles of differing sizes have different sound source levels.
Empirical data from recent sound source verification (SSV) studies
in Anchorage and Kodiak, Alaska were used to estimate sound source
levels (SSLs) for impact pile driving, vibratory pile driving/removal,
and down-the-hole drilling installations of the 42-inch steel pipe
permanent piles and the 36-inch steel pipe template piles (Austin et
al. 2016; Denes et al. 2016). These Alaskan construction sites were
generally assumed to best represent the environmental conditions found
in Skagway and represent the nearest available source level data for
42-inch steel piles.
Tables 4 provides the sound source values used in calculating
harassment isopleths for each source type. No data are currently
available for 42-inch steel
[[Page 64554]]
pipe piles. For impact and vibratory hammer source levels WP&YR used
the median levels measured by Austin et al. (2016) during installation
of 48-inch piles at Port of Anchorage (197.9 and 166.8 dB re 1 [mu]Pa
(rms at 11 m)). These 48-inch pile impact and vibratory levels are
conservatively used for both the 42-inch permanent piles and the 36-
inch template piles. Little SSL data are available for down-the-hole
drilling. WP&YR used the 90th percentile source levels measured by
Denes et al. (2016) during drilling down the center of 30-inch piles in
Kodiak (171 dB re 1 [mu]Pa (rms at 10 m)).
Table 4--Source Levels and Anticipated Daily Durations for Underwater Sound Calculations
[Hours or strikes per day represents the maximum duration of any single activity]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Source Source type SPLPK (dB) SPLRMS (dB) SELS S (dB) Hours or strikes per day
--------------------------------------------------------------------------------------------------------------------------------------------------------
Template Piles
Vibratory Installation/Removal.... Non-impulsive, continuous..... n/a 166.8 n/a 3 hours.
Impact Installation............... Impulsive, intermittent....... 212.5 197.9 186.7 2,000 strikes.
Drilling Installation............. Non-impulsive, continuous..... n/a 171.0 n/a 6 hours.
Permanent Piles
Vibratory Installation............ Non-impulsive, continuous..... n/a 166.8 n/a 8 hours.
Impact Installation............... Impulsive, intermittent....... 212.5 197.9 186.7 2,000 strikes.
Drilling Installation............. Non-impulsive, continuous..... n/a 171.0 n/a 8 hours.
--------------------------------------------------------------------------------------------------------------------------------------------------------
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 * Log10 (R1/R2),
Where:
TL = transmission loss in dB
B = transmission loss coefficient; for practical spreading equals 15
R1 = the distance of the modeled SPL from the driven
pile, and
R2 = the distance from the driven pile of the initial
measurement
A practical spreading value of fifteen is often used under conditions,
such as at the WP&YR Railroad Dock, where water increases with depth as
the receiver moves away from the shoreline, resulting in an expected
propagation environment that would lie between spherical and
cylindrical spreading loss conditions. Practical spreading loss is
assumed here.
When the NMFS Technical Guidance (2016) was published, in
recognition of the fact that ensonified area/volume could be more
technically challenging to predict because of the duration component in
the new thresholds, we developed a User Spreadsheet that includes tools
to help predict a simple isopleth that can be used in conjunction with
marine mammal density or occurrence to help predict takes. We note that
because of some of the assumptions included in the methods used for
these tools, we anticipate that isopleths produced are typically going
to be overestimates of some degree, which may result in some degree of
overestimate of Level A harassment take. However, these tools offer the
best way to predict appropriate isopleths when more sophisticated 3D
modeling methods are not available, and NMFS continues to develop ways
to quantitatively refine these tools, and will qualitatively address
the output where appropriate. For stationary sources such as pile
driving and drilling, NMFS User Spreadsheet predicts the closest
distance at which, if a marine mammal remained at that distance (or
greater) the whole duration of the activity, it would not incur PTS.
Inputs used in the User Spreadsheet and the resulting isopleths are
reported in Tables 5 and 6. As WP&YR plans to employ two continuous
sound sources (vibratory pile driving and drilling) it is necessary to
account for accumulation of sound caused by both activities during the
full 10 hour work day when calculating Level A harassment isopleths. As
drilling has the higher sound pressure level we propose to use drilling
to calculate the Level A harassment isopleths for both drilling and
vibratory pile driving activities (Table 5). For impact pile driving,
isopleths calculated using the SELCUM metric will be used as
it produces larger isopleths than SPLPK. Isopleths for Level
B harassment associated with impact pile driving (160 dB) and vibratory
pile driving/removal and drilling (120 dB) were also calculated and are
can be found in Table 6.
Table 5--User Spreadsheet Input Parameters Used for Calculating
Harassment Isopleths
------------------------------------------------------------------------
Vibratory pile
Parameter Impact pile driving driving and drilling
------------------------------------------------------------------------
Spreadsheet Tab Used........ E.1) Impact pile A.1) Drilling/
driving. Vibratory pile
driving.
Source Level................ 186.7 dB SEL........ 171 dB rms.
Weighting Factor Adjustment 2................... 2.
(kHz).
Number of strikes per day... 2,000............... N/A.
Activity Duration (h) within N/A................. 10 hours.
24-hour period.
Propagation (xLogR)......... 15LogR.............. 15LogR.
Distance of source level 11.................. 10.
measurement (meters).
------------------------------------------------------------------------
[[Page 64555]]
Table 6--Calculated Distances to Level A Harassment and Level B Harassment Isopleths During Pile Installation and Removal and Drilling
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level A harassment zone (meters) Level B
-------------------------------------------------------------------------------- harassment zone
(meters)
Source Low- frequency Mid- frequency High- Phocid Otariid -----------------
cetacean cetacean frequency pinniped pinniped Cetaceans and
cetacean pinnipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Drilling and Vibratory Installation................... 148 8.3 129.7 79.2 5.8 \1\ 13,000
Impact Installation................................... 3,077.2 109.4 3,665.4 1,646.8 119.9 3,698.8
rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr
Source................................................ PTS Onset Isopleth--Peak (meters)
rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr
Impact Installation................................... 4.1 n/a 55.1 4.7 n/a ................
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Based on maximum distance before landfall. Calculated distance was 25.1 km.
Marine Mammal Occurrence and Take Calculation and Estimation
In this section we provide the information about the presence,
density, or group dynamics of marine mammals that will inform the take
calculations, and how this information is brought together to produce a
quantitative take estimate.
Density information is not available for marine mammals in the
project area in Taiya Inlet. Potential exposures to impact and
vibratory pile driving noise for each threshold for all other marine
mammals were estimated using published reports of group sizes and
population estimates, and anecdotal observational reports from local
commercial entities. For several species, it is not currently possible
to identify all observed individuals to stock.
Level B Harassment Calculations
The estimation of takes by Level B harassment uses the following
calculation:
Level B harassment estimate = N (number of animals in the
ensonified area) * Number of days of noise generating activities.
Humpback Whale
Humpback whales are the most commonly observed baleen whale in
Southeast Alaska, particularly during spring and summer months.
Humpback whales in Alaska, although not limited to these areas, return
to specific feeding locations such as Frederick Sound, Chatham Strait,
North Pass, Sitka Sound, Glacier Bay, Point Adolphus, and Prince
William Sound, as well as other similar coastal areas (Wing and Krieger
1983). In Lynn Canal they have been observed in the spring and fall
from Haines to Juneau, however scientific surveys have not documented
the species within Taiya Inlet (Dahlheim et al. 2009).
Local observations indicate that humpback whales are not common in
the project action area but, if they are sighted, are generally present
during mid to late spring and vacate the area by July to follow large
aggregations of forage fish in lower Lynn Canal. Local observers have
reported humpback whales in Taiya Inlet, sometimes fairly close to the
Skagway waterfront. Due to seasonal migration patterns, the low
frequency of humpbacks in the area, and that no humpback whales have
been reported during winter months it is anticipated that no humpback
whales will be present in the project area in February. On average,
four to five individuals may occur near Skagway during the spring
eulachon run in April and May, after which, only a few individuals are
observed throughout the summer. In 2015, only one whale was observed
(for several) weeks close to Skagway (K. Gross, personal communication
reported in MOS 2016). Based on humpback whale occurrence in the
project area and local observations, it is estimated that four
individuals may be present in the action area each day during April,
coinciding with 30 days of project activity (120 exposures). As it is
unclear whether humpback whales occur in the inlet in March (for
example, should the eulachon run begin early), it is conservatively
estimated that one whale might be found in the inlet during that month
for five days (0.16 whales per day, 5 exposures), for an overall total
of 125 exposures (Table 7).
Table 7--Estimated Takes of Humpback Whales per Month
----------------------------------------------------------------------------------------------------------------
Animals in
Month inlet per day Days in month Exposures
----------------------------------------------------------------------------------------------------------------
February........................................................ 0 28 0
March........................................................... 0.16 31 5
April........................................................... 4 30 120
-----------------------------------------------
Total....................................................... .............. .............. 125
----------------------------------------------------------------------------------------------------------------
Minke Whale
Minke whales are rarely observed in the project area, and
scientific surveys have not documented the species within Taiya Inlet
(Dahlheim et al. 2009). A single minke whale was observed in the inlet
in 2015 (K. Gross, Never Monday Charters, personal communication; R.
Ford, Taiya Inlet Watershed Council, both personal communications
reported in MOS 2016), and is the only known record of a minke whale in
Taiya Inlet. However one minke whale was reported by local observers in
the action area in 2015. Based on the available information it is very
unlikely minke whales will be present in the inlet, however, minke
whale presence is possible based on a single sighting and presence of
potential prey (eulachon) in the spring. Thus, we estimate a total of
[[Page 64556]]
two potential exposures of minke whales.
Killer Whale
Although killer whale stocks' ranges include southeast Alaska, they
have only been documented as far north as Lynn Canal; therefore, while
possible, occurrence north of Lynn Canal into Taiya Inlet is rare.
According to local observations, pods of resident killer whales are
occasionally seen in Taiya Inlet. Local observations indicate killer
whales are observed four or five times a year (between spring and fall)
usually in a group of 15 to 20 whales. In 2015 a resident pod was only
observed in Taiya Inlet twice, remaining for one to four days per visit
(K. Gross, personal communication reported in MOS 2016). There is no
evidence of transient whales occurring within Taiya Inlet. While the
resident pods remain in Alaska year-round there are no reports of
sightings during winter months (January-February) in Taiya Inlet so it
is assumed no killer whales will be present in the project area in
February. Based on local observations in the project area in the
spring, it is assumed that a group of 20 whales may enter the project
area once in each of March and April and remain within the inlet for
two days each time, for a total of 80 potential exposures.
Harbor Porpoise
Harbor porpoises are primarily found in coastal waters, and in the
Gulf of Alaska and Southeast Alaska, they occur most frequently in
waters less than 100 meters (Dahlheim et al. 2009). Dedicated research
studies of harbor porpoise in the project area only occur as far north
in Lynn Canal as Haines during the summer (Dahlheim et al. 2009; 2015),
approximately 16 miles south of Skagway. Group sizes were, on average,
between 1.37-1.59 animals (less than 2) (Dahlheim et al. 2009; 2015).
In Lynn Canal, observations were less frequent, primarily in lower Lynn
Canal from Chatham Strait to Juneau, though harbor porpoises have been
observed as far north as Haines during the summer (Dahlheim et al.
2009; 2015).
Despite lack of observations during dedicated surveys, local
charter captains indicate that harbor porpoises commonly occur in small
groups of two or three in Taiya Inlet, although they are not
encountered on a daily basis and are rarely seen in areas close to the
waterfront (K. Gross, personal communication reported in MOS 2016).
Therefore, it is conservatively estimated that one group of three
individuals may be present in the inlet 75 percent of the days during
each month (or 2.25 porpoises per day on average) for a total of 201
potential exposures (Table 8).
Table 8--Estimated Takes of Harbor Porpoises per Month
----------------------------------------------------------------------------------------------------------------
Animals in
Month inlet per day Days in month Exposures
----------------------------------------------------------------------------------------------------------------
February........................................................ 2.25 28 63
March........................................................... 2.25 31 70
April........................................................... 2.25 30 68
-----------------------------------------------
Total....................................................... .............. .............. 201
----------------------------------------------------------------------------------------------------------------
Dall's Porpoise
Dall's porpoises are widely distributed across the entire North
Pacific Ocean. Throughout most of the eastern North Pacific they are
present during all months of the year, although there may be seasonal
onshore-offshore movements along the west coast of the continental
United States and winter movements of populations out of Prince William
Sound and areas in the Gulf of Alaska and Bering Sea (Muto et al.
2018). Dahlheim et al. (2009) observed Dall's porpoise throughout
Southeast Alaska, with concentrations of animals consistently found in
Lynn Canal, Stephens Passage, Icy Strait, upper Chatham Strait,
Frederick Sound, and Clarence Strait. Dahlheim et al. (2009),
documented Dall's porpoise in Lynn Canal as far north as Haines,
Alaska, about 15 miles south of Skagway.
Local observation indicate that three to six Dall's porpoises may
be present in Taiya Inlet during the early spring and late fall.
Observations have been occasional to sporadic and do not occur on a
daily basis. The species has not been observed during winter months and
has not been observed near the waterfront (K. Gross, personal
communication reported in MOS 2016). The mean group size of Dall's
porpoise in Southeast Alaska is estimated to be 3.7 individuals
(Dahlheim et al. 2009). Therefore, it is estimated that a group of four
Dall's porpoises will be present in the project area every other day in
March and April (2 per day), for a total of 122 potential exposures
(Table 9).
Table 9--Estimated Takes of Dall's Porpoises per Month
----------------------------------------------------------------------------------------------------------------
Animals in
Month inlet per day Days in month Exposures
----------------------------------------------------------------------------------------------------------------
February........................................................ 0 28 0
March........................................................... 2 31 62
April........................................................... 2 30 60
-----------------------------------------------
Total....................................................... .............. .............. 122
----------------------------------------------------------------------------------------------------------------
Steller Sea Lion
Several long-term Steller sea lion haulouts are located in Lynn
Canal, however none occur in Taiya Inlet. The nearest long-term Steller
sea lion haulout is located at Gran Point, south of Haines and 24 mi
(38 km) south of the project area. Other year-round haulouts in Lynn
Canal are present at Met Point, Benjamin Island, and Little Island,
closer to Juneau (Fritz et al. 2015). Observations from local charter
boat captains and watershed stewards indicate Steller sea lions can be
abundant in the action area, particularly in April and May during the
eulachon run, but are rarely observed in the project area during the
winter (K. Gross,
[[Page 64557]]
Never Monday Charters, personal communication; R. Ford, Taiya Inlet
Watershed Council, personal communication reported in MOS 2016). This
is consistent with the National Marine Mammal Laboratory database
(Fritz et al. 2015), which has identified the largest number of Lynn
Canal sea lions during the fall and winter months at Benjamin Island in
the lower reaches of the canal. During surveys conducted in 2002 and
2003, Womble et al. (2005) observed a maximum of approximately 400
Steller sea lions in the water at the mouth of the Taiya River feeding
on eulachon in 2003, but observed very few in the same area in 2002.
Steller sea lions have also been observed in Lutak Inlet, a foraging
site closer to both Taiya Point and Gran Point haulouts.
During the spring eulachon run, a seasonal haulout site is located
on Taiya Point at the southern tip of Taiya Inlet, approximately 11 mi
(18 km) from the project site. Twenty-five to 40 sea lions are
estimated to use this haulout for about three weeks during spring run,
during which they frequently are observed in the inlet (K. Gross,
personal communication reported in MOS 2016). However, most animals
leave the inlet shortly after the eulachon run and are rarely observed
in the summer. Based on survey data and local observations in the
project area, it is estimated that two animals may be present each day
in February, 16 animals may be present on each day in March (half of
the mean found on Taiya Rocks during the eulachon run), and 40 animals
may be present each day in April for a total of 1,032 potential
exposures (Table 10).
Table 10--Estimated Takes of Steller Sea Lions per Month
----------------------------------------------------------------------------------------------------------------
Animals in
Month inlet per day Days in month Exposures
----------------------------------------------------------------------------------------------------------------
February........................................................ 2 28 56
March........................................................... 16 31 496
April........................................................... 40 30 1,200
-----------------------------------------------
Total....................................................... .............. .............. 1,752
----------------------------------------------------------------------------------------------------------------
Harbor Seal
No long-term haulout sites have been documented for harbor seals in
Taiya Inlet; however, seasonal haulouts are present within six miles of
the project area at Seal Cove and at the mouth of the Taiya River.
Based on reports from local observers, a few resident harbor seals are
expected to occur within Taiya Inlet during the winter months, but
during the April and May eulachon run numbers can range from 20 to over
100 (K. Gross and R. Ford, personal communication reported in MOS
2016). Before and after the spawning run, much lower numbers of harbor
seals are present.
Based on survey data and local observations in the project area it
is assumed that 20 seals (the lower estimate in the range) occur within
the project area each day in February through March (560 takes in
February and 620 takes in March) and 100 seals (the higher estimate in
the range) during April (3,000 takes) for a total of 4,180 potential
exposures (Table 11).
Table 11--Estimated Takes of Harbor Seals per Month
----------------------------------------------------------------------------------------------------------------
Animals in
Month inlet per day Days in month Takes
----------------------------------------------------------------------------------------------------------------
February........................................................ 20 28 560
March........................................................... 20 31 620
April........................................................... 100 30 3,000
-----------------------------------------------
Total....................................................... .............. .............. 4,180
----------------------------------------------------------------------------------------------------------------
Level A Harassment Calculations
WP&YR intends to avoid Level A harassment take by shutting down
installation activities at approach of any marine mammal to the
representative Level A harassment (PTS onset) ensonification zone up to
a practical shutdown monitoring distance. As small/cryptic marine
mammal species may enter the Level A harassment zone before shutdown
mitigation procedures can be implemented, and some animals may occur
between the maximum Level A harassment ensonification zone and the
maximum shutdown safety zone, we conservatively estimate that 20
percent of the Level B harassment takes calculated above for humpback
whales, harbor porpoises, Dall's porpoises, and harbor seals, have the
potential to be takes by Level A harassment (Table 12). Minke whale
occurrence in Taiya Inlet is rare. Because vessel-based PSO are able to
monitoring the entire Level A harassment zone (whales entering the
inlet), WP&YR did not request, and NMFS is not proposing, to authorize
Level A harassment take of minke whales.
Table 12--Estimated Take by Level A and Level B Harassment, by Species and Stock, Resulting From Proposed WP&YR Project Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
Proposed take
Common name Stock Stock Level A Level B Total as percentage
abundance \1\ proposed take of stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale............................ Central North Pacific....... \2\10,103 25 100 125 1.23
Minke Whale............................... Alaska...................... N/A 0 2 2 N/A
[[Page 64558]]
Killer whale.............................. Alaska Resident............. 2,347 0 80 80 3.4
Northern Resident........... 261 30.6
Gulf of Alaska, Aleutian 587 13.6
Islands, Bering Sea
Transient.
West Coast Transient........ 243 32.9
Harbor porpoise........................... Southeast Alaska............ 975 40 161 201 20.6
Dall's porpoise........................... Alaska...................... 83,400 24 98 122 0.01
Steller sea lion.......................... Western U.S................. 54,267 0 \3\35 35 0.06
Eastern U.S................. 41,638 0 1,717 1,717 4.1
Harbor seal............................... Lynn Canal/Stephens Passage. 9,478 836 3,344 4,180 44.1
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Stock or DPS size is Nbest according to NMFS 2018 Draft Stock Assessment Reports.
\2\ For ESA section 7 consultation purposes, 6.1 percent are designated to the Mexico DPS and the remaining are designated to the Hawaii DPS; therefore,
we assigned 2 Level B takes to the Mexico DPS.
\3\ Based on the percent of branded animals at Gran Point and in consultation with the Alaska Regional Office, we used a 2 percent distinction factor to
determine the number of animals potentially from the western DPS.
There are a number of reasons why the estimates of potential
incidents of take are likely to be conservative. Given the lack of
density information, we use conservative estimates of marine mammal
presence to calculate takes for each species. Additionally, in the
context of stationary activities such as pile driving, and in areas
where resident animals may be present, this number represents the
number of instances of take that may occur to a small number of
individuals, with a notably smaller number of animals being exposed
more than once per individual. While pile driving or drilling can occur
any day throughout the in-water work window, and the analysis is
conducted on a per day basis, only a fraction of that time is actually
spent pile driving. The potential effectiveness of mitigation measures
in reducing the number of takes is also not quantified in the take
estimation process. For these reasons, these take estimates may be
conservative, especially if each take is considered a separate
individual animal, and especially for pinnipeds.
Proposed Mitigation
In order to issue an IHA under section 101(a)(5)(D) of the MMPA,
NMFS must set forth the permissible methods of taking pursuant to such
activity, and other means of effecting the least practicable impact on
such species or stock and its habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance, and on
the availability of such species or stock for taking for certain
subsistence uses (latter not applicable for this action). NMFS
regulations require applicants for incidental take authorizations to
include information about the availability and feasibility (economic
and technological) of equipment, methods, and manner of conducting such
activity or other means of effecting the least practicable adverse
impact upon the affected species or stocks and their habitat (50 CFR
216.104(a)(11)).
In evaluating how mitigation may or may not be appropriate to
ensure the least practicable adverse impact on species or stocks and
their habitat, as well as subsistence uses where applicable, we
carefully consider two primary factors:
(1) The manner in which, and the degree to which, the successful
implementation of the measure(s) is expected to reduce impacts to
marine mammals, marine mammal species or stocks, and their habitat.
This considers the nature of the potential adverse impact being
mitigated (likelihood, scope, range). It further considers the
likelihood that the measure will be effective if implemented
(probability of accomplishing the mitigating result if implemented as
planned) the likelihood of effective implementation (probability
implemented as planned), and;
(2) the practicability of the measures for applicant
implementation, which may consider such things as cost, impact on
operations, and, in the case of a military readiness activity,
personnel safety, practicality of implementation, and impact on the
effectiveness of the military readiness activity.
Mitigation for Marine Mammals and Their Habitat
In addition to the measures described later in this section, WP&YR
will employ the following standard mitigation measures:
Conduct briefings between construction supervisors and
crews and the marine mammal monitoring team prior to the start of all
pile driving activity, and when new personnel join the work, to explain
responsibilities, communication procedures, marine mammal monitoring
protocol, and operational procedures;
For in-water heavy machinery work other than pile driving
(e.g., standard barges, etc.), if a marine mammal comes within 10 m,
operations shall cease and vessels shall reduce speed to the minimum
level required to maintain steerage and safe working conditions. This
type of work could include the following activities: (1) Movement of
the barge to the pile location; or (2) positioning of the pile on the
substrate via a crane (i.e., stabbing the pile);
Work may only occur during daylight hours, when visual
monitoring of marine mammals can be conducted;
For those marine mammals for which Level B harassment take
has not been requested, in-water pile installation/removal and drilling
will shut down immediately if such species are observed within or on a
path towards the monitoring zone (i.e., Level B harassment zone); and
If take reaches the authorized limit for an authorized
species, pile installation will be stopped as these species approach
the Level B harassment zone to avoid additional take.
The following measures would apply to WP&YR's mitigation
requirements:
Establishment of Shutdown Zone for Level A Harassment--For all pile
[[Page 64559]]
driving/removal and drilling activities, WP&YR would establish a
shutdown zone. The purpose of a shutdown zone is generally to define an
area within which shutdown of activity would occur upon sighting of a
marine mammal (or in anticipation of an animal entering the defined
area). Conservative shutdown zones of 150 m for low- and high-
frequency cetaceans, 80 m for phocid pinnipeds, and 10 m for mid-
frequency cetaceans and otariid pinnipeds would be used during all
drilling and vibratory pile driving/removal activities to prevent
incidental Level A harassment exposure for these activities (Table 13).
During impact pile driving a 150 m zone would be used for all species
except for low-frequency cetacean for which a 2,000 m zone will be
used. These shutdown zones would be used to prevent incidental Level A
exposures from impact pile driving for mid-frequency cetaceans and
otariid pinnipeds, and to reduce the potential for such take for other
species (Table 13). The placement of Protected Species Observers (PSOs)
during all pile driving and drilling activities (described in detail in
the Monitoring and Reporting Section) will ensure shutdown zones are
visible. The 150 m zone is the practical distance WP&YR anticipates
phocid pinnipeds and high-frequency cetaceans can be effectively
observed in the project area. The 2,000 m zone for low-frequency
cetaceans is determined by the width of Taiya Inlet at Skagway Harbor.
Observers will be present on vessels in the Taiya Inlet and able to
observe large whales traveling north into the inlet and project area.
Table 13--Monitoring and Shutdown Zones for Each Project Activity
------------------------------------------------------------------------
Monitoring
Source zone (m) Shutdown zone (m)
------------------------------------------------------------------------
Drilling and Vibratory 13,000 Low- and high-
Installation/Removal. frequency cetaceans:
150.
Phocid pinnipeds: 80.
Mid-frequency cetaceans
and otariid pinnipeds:
10.
Impact Installation............ 3,400 Low-frequency
cetaceans: 2,000.
All other species: 150.
------------------------------------------------------------------------
Establishment of Monitoring Zones for Level B Harassment--WP&YR
would establish monitoring zones to correlate with Level B disturbance
zones or zones of influence which are areas where SPLs are equal to or
exceed the 160 dB rms threshold for impact driving and the 120 dB rms
threshold during vibratory driving and drilling. 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 area outside the shutdown zone and thus prepare for a potential
cease of activity should the animal enter the shutdown zone. The
proposed monitoring zones are described in Table 13. The monitoring
zone for drilling and vibratory pile driving/removal activities is
13,000 m, corresponding to the maximum distance before landfall.
Placement of PSOs on vessels in the Taiya Inlet allow PSOs to observe
marine mammals traveling north into the inlet and Skagway Harbor.
Should PSOs determine the monitoring zone cannot be effectively
observed in its entirety, Level B harassment exposures will be recorded
and extrapolated based upon the number of observed take and the
percentage of the Level B zone that was not visible.
Soft Start--The use of soft-start procedures are believed to
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 strikes from the hammer
at reduced energy, with each strike followed by a 30-second waiting
period. This procedure would be conducted a total of three times before
impact pile driving begins. 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 thirty minutes or
longer. Soft start is not required during vibratory pile driving and
removal activities.
Pre-Activity Monitoring--Prior to the start of daily in-water
construction activity, or whenever a break in pile driving/removal or
drilling of 30 minutes or longer occurs, PSOs will observe the shutdown
and monitoring zones for a period of 30 minutes. The shutdown zone will
be 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 zone, a soft-start cannot proceed until the animal has left
the zone or has not been observed for 15 minutes. If the Level B
harassment zone has been observed for 30 minutes and non-permitted
species are not present within the zone, soft start procedures can
commence and work can continue even if visibility becomes impaired
within the Level B monitoring zone. When a marine mammal permitted for
Level B take is present in the Level B harassment zone, activities may
begin and Level B take will be recorded. As stated above, if the entire
Level B zone is not visible at the start of construction, piling or
drilling activities can begin. If work ceases for more than 30 minutes,
the pre-activity monitoring of both the Level B and shutdown zone will
commence.
Due to the depth of the water column and strong currents present at
the project site, bubble curtains would not be implemented as they
would not be effective in this environment.
Based on our evaluation of the applicant's proposed measures, 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 in the
proposed action area. Effective reporting is critical both to
compliance as well as to ensuring that the most value is obtained from
the required monitoring.
[[Page 64560]]
Monitoring and reporting requirements prescribed by NMFS should
contribute to improved understanding of one or more of the following:
Occurrence of marine mammal species or stocks in the area
in which take is anticipated (e.g., presence, abundance, distribution,
density);
Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) Action or environment
(e.g., source characterization, propagation, ambient noise); (2)
affected species (e.g., life history, dive patterns); (3) co-occurrence
of marine mammal species with the action; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors;
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks;
Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important physical components of
marine mammal habitat); and
Mitigation and monitoring effectiveness.
Marine Mammal Visual Monitoring
Monitoring shall be conducted by NMFS-approved observers. Trained
observers shall be placed from the best vantage point(s) practicable to
monitor for marine mammals and implement shutdown or delay procedures
when applicable through communication with the equipment operator.
Observer training must be provided prior to project start, and shall
include instruction on species identification (sufficient to
distinguish the species in the project area), description and
categorization of observed behaviors and interpretation of behaviors
that may be construed as being reactions to the specified activity,
proper completion of data forms, and other basic components of
biological monitoring, including tracking of observed animals or groups
of animals such that repeat sound exposures may be attributed to
individuals (to the extent possible).
Monitoring would be conducted 30 minutes before, during, and 30
minutes after pile driving/removal and drilling activities. In
addition, observers shall record all incidents of marine mammal
occurrence, regardless of distance from activity, and shall document
any behavioral reactions in concert with distance from piles being
driven or removed. Pile driving/removal and drilling 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.
A total of five PSOs would be based on land and vessels. During all
pile driving/removal and drilling activities observers will be
stationed at the Railroad Dock, Yakutania Point, and Dyea Point. These
stations will allow full monitoring of the impact hammer monitoring
zone and the Level A shutdown zones. The vibratory and drilling
monitoring zone will be additionally monitored using two PSOs stationed
on boats anchored near the shoreline, with each team (vessel operator
and observer) stationed approximately 2 km apart in the inlet south of
the project site (Figure 2 in the WP&YR Marine Mammal Mitigation and
Monitoring Plan).
PSOs would scan the waters using binoculars, and/or spotting
scopes, and would use a handheld GPS or range-finder device to verify
the distance to each sighting from the project site. All PSOs would be
trained in marine mammal identification and behaviors and are required
to have no other project-related tasks while conducting monitoring. In
addition, monitoring will be conducted by qualified observers, who will
be placed at the best vantage point(s) practicable to monitor for
marine mammals and implement shutdown/delay procedures when applicable
by calling for the shutdown to the hammer operator. WP&YR would adhere
to the following observer qualifications:
(i) Independent observers (i.e., not construction personnel) are
required.
(ii) At least one observer must have prior experience working as an
observer.
(iii) Other observers may substitute education (degree in
biological science or related field) or training for experience.
(iv) Where a team of three or more observers are required, one
observer shall be designated as lead observer or monitoring
coordinator. The lead observer must have prior experience working as an
observer.
(v) WP&YR shall submit observer CVs for approval by NMFS.
Additional standard observer qualifications include:
Ability to conduct field observations and collect data
according to assigned protocols Experience or training in the field
identification of marine mammals, including the identification of
behaviors;
Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
Writing skills sufficient to prepare a report of
observations including but not limited to the number and species of
marine mammals observed; dates and times when in-water construction
activities were conducted; dates and times when in-water construction
activities were suspended to avoid potential incidental injury from
construction sound of marine mammals observed within a defined shutdown
zone; and marine mammal behavior; and
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.
A draft marine mammal monitoring report would be submitted to NMFS
within 90 days after the completion of pile driving and removal and
drilling activities. It will include an overall description of work
completed, a narrative regarding marine mammal sightings, and
associated PSO data sheets. Specifically, the report must include:
Date and time that monitored activity begins or ends;
Construction activities occurring during each observation
period;
Weather parameters (e.g., percent cover, visibility);
Water conditions (e.g., sea state, tide state);
Species, numbers, and, if possible, sex and age class of
marine mammals;
Description of any observable marine mammal behavior
patterns, including bearing and direction of travel and distance from
pile driving activity;
Distance from pile driving activities to marine mammals
and distance from the marine mammals to the observation point;
Locations of all marine mammal observations; and
Other human activity in the area.
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.
In the unanticipated event that the specified activity clearly
causes the take of a marine mammal in a manner prohibited by the IHA
(if issued), such as an injury, serious injury or mortality, WP&YR
would immediately cease the
[[Page 64561]]
specified activities and report the incident to the Chief of the
Permits and Conservation Division, Office of Protected Resources, NMFS,
and the Alaska Regional Stranding Coordinator. The report would include
the following information:
Description of the incident;
Environmental conditions (e.g., Beaufort sea state,
visibility);
Description of all marine mammal observations in the 24
hours preceding the incident;
Species identification or description of the animal(s)
involved;
Fate of the animal(s); and
Photographs or video footage of the animal(s) (if
equipment is available).
Activities would not resume until NMFS is able to review the
circumstances of the prohibited take. NMFS would work with WP&YR to
determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. WP&YR would not be able to
resume their activities until notified by NMFS via letter, email, or
telephone.
In the event that WP&YR discovers an injured or dead marine mammal,
and the lead PSO determines that the cause of the injury or death is
unknown and the death is relatively recent (e.g., in less than a
moderate state of decomposition as described in the next paragraph),
WP&YR would immediately report the incident to the Chief of the Permits
and Conservation Division, Office of Protected Resources, NMFS, and the
NMFS Alaska Stranding Hotline and/or by email to the Alaska Regional
Stranding Coordinator. The report would include the same information
identified in the paragraph above. Activities would be able to continue
while NMFS reviews the circumstances of the incident. NMFS would work
with WP&YR to determine whether modifications in the activities are
appropriate.
In the event that WP&YR discovers an injured or dead marine mammal
and the lead PSO determines that the injury or death is not associated
with or related to the activities authorized in the IHA (e.g.,
previously wounded animal, carcass with moderate to advanced
decomposition, or scavenger damage), WP&YR would report the incident to
the Chief of the Permits and Conservation Division, Office of Protected
Resources, NMFS, and the NMFS Alaska Stranding Hotline and/or by email
to the Alaska Regional Stranding Coordinator, within 24 hours of the
discovery. WP&YR would provide photographs, video footage (if
available), or other documentation of the stranded animal sighting to
NMFS and the Marine Mammal Stranding Network.
Acoustic Monitoring
WP&YR will conduct acoustic monitoring for the purposes of SSV.
WP&YR will collect acoustic data for at least one 42-inch permanent
pile, using all three installation methods (impact pile driving,
vibratory pile driving, and down-the-hole drilling) from at least two
distances from the pile (one approximately 10 meters from the pile and
at least one additional measurement in the far field). The following
data, at minimum, shall be collected during acoustic monitoring and
reported:
Hydrophone equipment and methods: recording device,
sampling rate, distance from the pile where recordings were made; depth
of recording device(s);
Type of pile (42-inch), and segment of pile (1, 2, or 3),
being driven and method of driving/removal or drilling during
recordings; and
Mean, median, maximum (or 90th percentile), and range
sound levels (dB re 1[micro]Pa): cumulative sound exposure level
(SELCUM), peak sound pressure level (SPLPK), root
mean square sound pressure level (SPLRMS), and single-strike
sound exposure level (SELS-S) as appropriate for the sound
source.
For more details please see WP&YR's acoustic monitoring plan,
available at https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities.
Negligible Impact Analysis and Determination
NMFS has defined negligible impact as an impact resulting from the
specified activity that cannot be reasonably expected to, and is not
reasonably likely to, adversely affect the species or stock through
effects on annual rates of recruitment or survival (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough
information on which to base an impact determination. In addition to
considering estimates of the number of marine mammals that might be
``taken'' through harassment, NMFS considers other factors, such as the
likely nature of any responses (e.g., intensity, duration), the context
of any responses (e.g., critical reproductive time or location,
migration), as well as effects on habitat, and the likely effectiveness
of the mitigation. We also assess the number, intensity, and context of
estimated takes by evaluating this information relative to population
status. Consistent with the 1989 preamble for NMFS' implementing
regulations (54 FR 40338; September 29, 1989), the impacts from other
past and ongoing anthropogenic activities are incorporated into this
analysis via their impacts on the environmental baseline (e.g., as
reflected in the regulatory status of the species, population size and
growth rate where known, ongoing sources of human-caused mortality, or
ambient noise levels).
Pile driving/removal and drilling activities associated with the
Railroad Dock installation 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 A
harassment and Level B harassment from underwater sounds generated from
pile driving and removal and down-the-hole drilling. Potential takes
could occur if individuals of these species are present in the
ensonified zone when these activities are underway.
The takes from Level A and Level B harassment would be due to
potential behavioral disturbance, TTS, and PTS. No mortality is
anticipated given the nature of the activity and measures designed to
minimize the possibility of injury to marine mammals. Level A
harassment is only anticipated for humpback whales, Dall's porpoise,
harbor porpoise, and harbor seal. The potential for harassment is
minimized through the construction method and the implementation of the
planned mitigation measures (see Proposed Mitigation section).
As described previously, minke whales are considered rare in the
proposed project area and we have proposed to authorize only nominal
and precautionary take of two individuals. Therefore, we do not expect
meaningful impacts to minke whales and preliminarily find that the
total minke whale take from each of the specified activities will have
a negligible impact on this species.
For remaining species, we discuss the likely effects of the
specified activities in greater detail. Effects on individuals that are
taken by Level B harassment, on the basis of reports in the literature
as well as monitoring from other similar activities, will likely be
limited to reactions such as increased swimming speeds, increased
surfacing time, or decreased foraging (if such activity were occurring)
(e.g., Thorson and Reyff 2006; HDR, Inc. 2012; Lerma 2014; ABR 2016).
Most likely, individuals will simply move away from the sound source
and be temporarily displaced
[[Page 64562]]
from the areas of pile driving and drilling, although even this
reaction has been observed primarily only in association with impact
pile driving. The pile driving activities analyzed here are similar to,
or less impactful than, numerous other construction activities
conducted in southeast Alaska, which have taken place with no known
long-term adverse consequences from behavioral harassment. Level B
harassment will be reduced to the level of least practicable adverse
impact through use of mitigation measures described herein and, if
sound produced by project activities is sufficiently disturbing,
animals are likely to simply avoid the area while the activity is
occurring. While vibratory driving and drilling associated with the
proposed project may produce sound at distances of many kilometers from
the project site, thus intruding on some habitat, the project site
itself is located in a busy harbor and the majority of sound fields
produced by the specified activities are close to the harbor.
Therefore, we expect that animals annoyed by project sound would simply
avoid the area and use more-preferred habitats.
In addition to the expected effects resulting from authorized Level
B harassment, we anticipate that humpback whales, harbor porpoises,
Dall's porpoises, and harbor seals may sustain some limited Level A
harassment in the form of auditory injury. However, animals in these
locations that experience PTS would likely only receive slight PTS,
i.e. minor degradation of hearing capabilities within regions of
hearing that align most completely with the energy produced by pile
driving, i.e. the low-frequency region below 2 kHz, not severe hearing
impairment or impairment in the regions of greatest hearing
sensitivity. If hearing impairment occurs, it is most likely that the
affected animal would lose a few decibels in its hearing sensitivity,
which in most cases is not likely to meaningfully affect its ability to
forage and communicate with conspecifics. As described above, we expect
that marine mammals would be likely to move away from a sound source
that represents an aversive stimulus, especially at levels that would
be expected to result in PTS, given sufficient notice through use of
soft start.
The project also is not expected to have significant adverse
effects on affected marine mammals' habitat. The project activities
would not modify existing marine mammal habitat for a significant
amount of time. The activities may cause some fish to leave the area of
disturbance, thus temporarily impacting marine mammals' foraging
opportunities in a limited portion of the foraging range; but, because
of the short duration of the activities and the relatively small area
of the habitat that may be affected, the impacts to marine mammal
habitat are not expected to cause significant or long-term negative
consequences.
In summary and as described above, the following factors primarily
support our preliminary determination that the impacts resulting from
this activity are not expected to adversely affect the species or stock
through effects on annual rates of recruitment or survival:
No mortality is anticipated or authorized;
Conduct the majority of pile driving/removal and drilling
work outside of the eulachon run, minimizing harassment of marine
mammals during important foraging times;
The Level A harassment exposures are anticipated to result
only in slight PTS, within the lower frequencies associated with pile
driving;
The anticipated incidents of Level B harassment consist
of, at worst, temporary modifications in behavior that would not result
in fitness impacts to individuals;
The specified activity and ensonification area is very
small relative to the overall habitat ranges of all species and does
not include habitat areas of special significance (BIAs or ESA-
designated critical habitat); and
The presumed efficacy of the proposed mitigation measures
in reducing the effects of the specified activity to the level of least
practicable adverse impact.
In addition, although affected humpback whales and Steller sea
lions may be from a DPS that is listed under the ESA, it is unlikely
that minor noise effects in a small, localized area of habitat would
have any effect on the stocks' 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.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the proposed monitoring and
mitigation measures, NMFS preliminarily finds that the total marine
mammal take from the proposed activity will have a negligible impact on
all affected marine mammal species or stocks.
Small Numbers
As noted above, only small numbers of incidental take may be
authorized under sections 101(a)(5)(A) and (D) of the MMPA for
specified activities other than military readiness activities. The MMPA
does not define small numbers and so, in practice, where estimated
numbers are available, NMFS compares the number of individuals taken to
the most appropriate estimation of abundance of the relevant species or
stock in our determination of whether an authorization is limited to
small numbers of marine mammals. Additionally, other qualitative
factors may be considered in the analysis, such as the temporal or
spatial scale of the activities.
Table 12 demonstrates the number of animals that could be exposed
to received noise levels that could cause Level A harassment and Level
B harassment for the proposed work in the WP&YR project area. With the
exception of the Northern Resident and West Coast Transient killer
whale stocks and harbor seals, our analysis shows that less than 25
percent of each affected stock could be taken by harassment. The
numbers of animals proposed to be taken for these stocks would be
considered small relative to the relevant stock's abundances even if
each estimated taking occurred to a new individual--an extremely
unlikely scenario.
The total proposed authorized take for killer whales as compared to
each potentially affected stock ranges from 3.4 percent to 32.9 percent
of each stock abundance. In reality, it is highly unlikely that 80
individuals of any one killer whale stock will be temporarily harassed.
Instead, it is assumed that there will be a relatively brief period of
takes of a smaller number of the same individuals from any stock (20,
which is representative of the estimated group size, or 40, if
individuals from the same stock are taken), which would result in
smaller percentages of stocks (ranging from 0.9 percent to 8.2 percent
if 20 whales from the same stock, or 1.7 percent to 16.5 percent if 40
whales from the same stock). We make this assumption because the Alaska
and Northern resident stocks are known to occasionally occur in Taiya
Inlet, but other stocks' (e.g., transients) range extends into the
project area, and therefore they may occur in the upper reaches of Lynn
Canal into Taiya Inlet towards Skagway, albeit infrequently. Takes are
not assumed to include multiple harassments of the same individual(s),
resulting in estimates of
[[Page 64563]]
proposed take as a percentage of stock abundance that are high compared
to actual take that will occur. This is the case with the resident
stocks of killer whale and harbor seal (Lynn Canal/Stephens Passage
stock).
As reported, a small number of harbor seals, most of which reside
in Taiya Inlet year-round, will be exposed to construction activities
for three months. The total population estimate in the Lynn Canal/
Stephens Passage stock is 9,478 animals over 1.37 million acres (5,500
km\2\) of area in their range, which results in an estimated density of
36 animals within Taiya Inlet. The largest Level B harassment zone
within the inlet occupies 17.9 km\2\, which represents less than 0.4
percent of the total geographical area occupied by the stock. The great
majority of these exposures will be to the same animals given their
residency patterns.
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
There are no relevant subsistence uses of the affected marine
mammal stocks or species implicated by this action. The proposed
project will occur near but not overlap with the subsistence area used
by the villages of Hoonah and Angoon (Wolfe et al. 2013; N. Kovaces,
Skagway Traditional Council, personal communication). Harbor seals and
Steller sea lions are available for subsistence harvest in this area
(Wolfe et al. 2013). Therefore, NMFS has preliminarily determined that
the total taking of affected species or stocks would not have an
unmitigable adverse impact on the availability of such species or
stocks for taking for subsistence purposes.
Endangered Species Act
Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16
U.S.C. 1531 et seq.) requires that each Federal agency insure that any
action it authorizes, funds, or carries out is not likely to jeopardize
the continued existence of any endangered or threatened species or
result in the destruction or adverse modification of designated
critical habitat. To ensure ESA compliance for the issuance of IHAs,
NMFS consults internally, in this case with the Alaska Regional Office,
whenever we propose to authorize take for endangered or threatened
species.
NMFS is proposing to authorize take of the Steller sea lion western
DPS and humpback whale Mexico DPS, which are listed under the ESA. On
November 29, 2018, the NMFS Office of Protected Resources has requested
initiation of section 7 consultation with the Alaska Regional Office
for the issuance of this IHA. NMFS will conclude the ESA consultation
prior to reaching a determination regarding the proposed issuance of
the authorization.
Proposed Authorization
As a result of these preliminary determinations, NMFS proposes to
issue an IHA to WP&YR for conducting the Railroad Dock dolphin
installation project in Skagway, Alaska from February 1, 2019 through
April 30, 2019, provided the previously mentioned mitigation,
monitoring, and reporting requirements are incorporated. A draft of the
IHA itself is available for review in conjunction with this notice at
https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities
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
action. We also request comment on the potential for 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 our final decision on the request for MMPA authorization.
On a case-by-case basis, NMFS may issue a second one-year IHA
without additional notice when (1) another year of identical or nearly
identical activities as described in the Specified Activities section
is planned or (2) the activities would not be completed by the time the
IHA expires and a second IHA would allow for completion of the
activities beyond that described in the Dates and Duration section,
provided all of the following conditions are met:
A request for renewal is received no later than 60 days
prior to expiration of the current IHA.
The request for renewal must include the following:
(1) An explanation that the activities to be conducted beyond the
initial dates either are identical to the previously analyzed
activities or include changes so minor (e.g., reduction in pile size)
that the changes do not affect the previous analyses, take estimates,
or mitigation and monitoring requirements.
(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 remain the same and appropriate,
and the original findings remain valid.
Dated: December 12, 2018.
Donna S. Weiting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2018-27258 Filed 12-14-18; 8:45 am]
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