[Federal Register Volume 85, Number 154 (Monday, August 10, 2020)]
[Notices]
[Pages 48206-48225]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-17409]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[RTID 0648-XA267]
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to the Transit Protection Program Pier
and Support Facilities Project at Naval Base Kitsap Bangor, Washington
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 the U.S. Navy (Navy) for
authorization to take marine mammals incidental to the Transit
Protection Program Pier and Support Facilities Project at Naval Base
Kitsap Bangor in Silverdale, Washington over two years. Pursuant to the
Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its
proposal to issue two incidental harassment authorizations (IHAs) to
incidentally take marine mammals during the specified activities. NMFS
is also requesting comments on possible one-time, one-year renewals
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
September 9, 2020.
ADDRESSES: Comments should be addressed to Jolie Harrison, Chief,
[[Page 48207]]
Permits and Conservation Division, Office of Protected Resources,
National Marine Fisheries Service, and submitted via email 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, including all attachments, must
not exceed a 25-megabyte file size. All comments received are a part of
the public record and will generally be posted online at 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: Leah Davis, 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
geographical region if certain findings are made and either regulations
are issued or, if the taking is limited to harassment, a notice of a
proposed incidental take authorization may be provided to the public
for review.
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other ``means of effecting the least practicable adverse
impact'' on the affected species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of the species or stocks for
taking for certain subsistence uses (referred to in shorthand as
``mitigation''); and requirements pertaining to the mitigation,
monitoring and reporting of the takings are set forth. The definitions
of all applicable MMPA statutory terms cited above are included in the
relevant sections below.
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must review our proposed action (i.e., the issuance of an IHA)
with respect to potential impacts on the human environment.
This action is consistent with categories of activities identified
in Categorical Exclusion B4 (IHAs with no anticipated serious injury or
mortality) of the Companion Manual for NOAA Administrative Order 216-
6A, which do not individually or cumulatively have the potential for
significant impacts on the quality of the human environment and for
which we have not identified any extraordinary circumstances that would
preclude this categorical exclusion. Accordingly, NMFS has
preliminarily determined that the issuance of the proposed IHA
qualifies to be categorically excluded from further NEPA review.
We will review all comments submitted in response to this notice
prior to concluding our NEPA process or making a final decision on the
IHA request.
Summary of Request
On January 14, 2020, NMFS received a request from the Navy for an
IHA to take marine mammals incidental to the Transit Protection Program
Pier and Support Facilities Project at Naval Base Kitsap Bangor in
Silverdale, Washington over two years. The Navy submitted a revised
application on March 23, 2020, which was deemed adequate and complete
on June 10, 2020. The Navy's request is for take of a small number of
five species of marine mammals, by Level B harassment and Level A
harassment. Neither the Navy nor NMFS expects serious injury or
mortality to result from this activity and, therefore, IHAs are
appropriate.
The IHAs, if issued, will be effective from July 16, 2021 to
January 15, 2022 for Year 1 activities, and July 16, 2022 to January
15, 2023 for Year 2 activities.
Description of Proposed Activity
Overview
The Navy is proposing to construct and operate a pier for berthing
of Transit Protection Program (TPP) blocking vessels, which provide
security escort to Fleet Ballistic Missile Submarines between Naval
Base Kitsap Bangor and the Strait of Juan de Fuca. These vessels are
currently berthed on a space-available basis at various locations at
Kitsap Bangor. Kitsap Bangor is located on Hood Canal approximately 20
miles (mi) (32 kilometers (km)) west of Seattle, Washington.
Construction activities include vibratory and impact pile driving and
vibratory pile removal, over approximately 80 days in year 1 and 10
days in year 2.
Dates and Duration
The Navy anticipates that construction for the TPP project will
occur over two years. The proposed IHAs would be effective from July
16, 2021 to January 15, 2022 for Year 1 activities, and July 16, 2022
to January 15, 2023 for Year 2 activities. The Navy expects that pile
driving will require a maximum of 90 in-water pile-driving days over
the two-year period. They anticipate completing the majority of the
proposed construction during Year 1 on approximately 80 in-water
workdays. Year 2 activities will include fender pile and guide pile
installation only on approximately 10 in-water workdays. Pile driving
and removal are expected to occur up to five hours per day during
daylight hours. Each year, pile driving will occur during the in-water
work window (IWWW) at Kitsap Bangor from July 16 to January 15. This
IWWW is typically imposed by the U.S. Army Corps of Engineers, the U.S.
Fish and Wildlife Service (USFWS), and the NMFS in an effort to avoid
in-water construction when Endangered Species Act (ESA)-listed juvenile
salmonids are most likely to be present.
Specific Geographic Region
Naval Base Kitsap Bangor is located north of the community of
Silverdale in Kitsap County on the Hood Canal. Hood Canal is a long,
narrow, fjord-like basin of western Puget Sound, characterized by
relatively steep sides and irregular seafloor topography. In the
entrance to Hood Canal, water depths in the center of the waterway near
Admiralty Inlet vary between 300 and 420 feet (ft) (91 and 128 m). As
the canal extends southwestward toward the Olympic Mountain Range and
Thorndyke Bay, water depth decreases to approximately 160 ft (49 m).
The proposed location for the TPP Pier is at the tip of the Keyport/
[[Page 48208]]
Bangor Spit, north of the Keyport/Bangor Dock (Figure 1). The Bangor
waterfront on Naval Base Kitsap occupies approximately 5 mi (8 km) of
the shoreline within northern Hood Canal (1.7 percent of the entire
Hood Canal coastline). Depths in the center of the waterway off the
Bangor waterfront are generally 200 to 400 ft (61 to 122 m).
Human-generated sound is a significant contributor to the ambient
acoustic environment at Kitsap Bangor. Normal port activities include
vessel traffic from large ships, support vessels and security boats,
and loading and maintenance operations, which all generate underwater
sound (Urick, 1983). Other sources of human-generated underwater sound
not specific to naval installations include sounds from echo sounders
on commercial and recreational vessels, industrial ship noise, and
noise from recreational boat engines.
[GRAPHIC] [TIFF OMITTED] TN10AU20.003
Detailed Description of Specific Activity
The Navy plans to construct a pier for berthing TPP blocking
vessels. The TPP pier will consist of an L-shaped, pile-supported
trestle from shore connecting to a pile-supported main pier section.
The Navy will also install two dolphins, one south and one north of the
pier which will be used solely for mooring support. Additionally, the
contractor will construct a temporary work trestle (falsework piles and
timber decking) for use during construction.
The proposed TPP pier will consist of an L-shaped pile-supported
trestle from shore connecting to a pile-supported main pier section.
The trestle will be concrete and approximately 114 ft (34.7 m) long and
39 ft (11.9 m) wide, including a pedestrian walkway. The main pier
section will also be concrete and approximately 299 ft (91.1 m) long
and 69 ft (21 m) wide.
The contractor will need to construct a 140-ft (42.6 m) by 20-ft
(6.1 m) temporary work trestle (falsework piles and timber decking).
The permanent trestle piles in the intertidal area will be driven from
the deck of the temporary work trestle; the temporary trestle will
subsequently be removed using a vibratory hammer.
Pier and trestle construction will require one derrick barge with a
crane and one support/material barge.
The Navy plans to install a fender system along the west face of
the pier with two berthing camels where the blocking vessels will tie
up to the pier. Each camel will be 65 ft (19.8 m) long by 12 ft (3.7 m)
wide and constructed of grated material. The camels will serve as both
a standoff for the blocking vessels and a platform for boarding the
blocking vessels. The camels will be accessed via brows down from the
main pier deck. The brow platforms and brows will also be constructed
of grated material. NMFS does not expect camel or brow platform
installation to result in the take of marine mammals, and we do not
discuss their installation further in this notice.
The fender piles will be installed on the outer side of the pier to
protect it from accidental damage by vessels. Where geotechnical
conditions do not allow piles to be driven to the required depth using
vibratory methods, an
[[Page 48209]]
impact hammer may be used to drive some of the 36-in (91.4 cm) support
piles for part or all of their length. The 24-in (61.0 cm) fender piles
and 30-in (76.2 cm) camel guide piles will not be impact driven.
The Navy plans to construct two dolphins, one south of the pier,
and one north of the pier for mooring support. The dolphins will
support mooring hardware for the bow and stern lines of the blocking
vessels. The structural system for the mooring dolphins will consist of
a 12 ft by 12 ft (3.7 m by 3.7 m) cast-in-place concrete pile cap and
four 36-inch battered steel pipe piles. The Navy plans to construct a
shoreline abutment under the pier trestle. The shoreline abutment will
be constructed from sheet piles and will be constructed landward of
mean higher high water (MHHW). Therefore, we do not expect the
shoreline abutment to result in take of marine mammals, and it is not
discussed further in this notice.
The trestle, pier, and dolphins will require in-water installation
of a total of 120 permanent steel piles that are 24, 30, or 36 inches
in diameter, and 40 temporary steel falsework piles that are 36 inches
in diameter.
An additional four 36-inch trestle support piles and 20 36-inch
falsework piles will be located above MHHW, however, we do not expect
installation of piles above MHHW to result in take of marine mammals,
and these piles are not discussed further.
The Navy will primarily install piles using a vibratory hammer, but
may use an impact hammer to install steel support piles. Steel support
piles will be advanced to the extent practicable with a vibratory
driver. For load-bearing structures, an impact hammer is typically
required to strike a pile a number of times to ensure it has met the
load-bearing specifications, a process referred to as ``proofing.''
Piles will only be impact driven when required for proofing or when a
pile cannot be advanced with a vibratory driver due to hard substrate
conditions. The Navy does not plan to conduct pile driving with
multiple hammers concurrently.
Table 1--Summary of Piles To Be Installed or Removed in Year 1 Across
All Structures
------------------------------------------------------------------------
Number of in-
Pile type Driving method water piles
------------------------------------------------------------------------
36-inch Steel Pipe Piles.......... Vibratory and Impact 100
(proofing).
36-inch Steel Falsework Piles..... Vibratory........... \a\ 40
------------------------------------------------------------------------
\a\ These piles will be installed and later removed.
Table 2--Summary of Piles To Be Installed in Year 2
------------------------------------------------------------------------
Number of in-
Pile type Driving method water piles
------------------------------------------------------------------------
24-inch Steel Fender Piles........ Vibratory........... 10
30-inch Steel Guide Piles......... Vibratory........... 10
------------------------------------------------------------------------
Navy will also conduct several construction activities in upland
areas, including installation of diesel fuel tanks, installation of a
paved parking area, construction of a vessel maintenance facility,
among other activities. Given their location, we do not expect any of
these upland construction activities to result in the take of marine
mammals, and they are not discussed further in this notice. Please
refer to the Navy's application for additional detail on these project
components.
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's Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species
(e.g., physical and behavioral descriptions) may be found on NMFS's
website (https://www.fisheries.noaa.gov/find-species).
Table 3 lists all species or stocks for which take is expected and
proposed to be authorized for this action, and summarizes information
related to the population or stock, including regulatory status under
the MMPA and ESA and potential biological removal (PBR), where known.
For taxonomy, we follow Committee on Taxonomy (2020). PBR is defined by
the MMPA as the maximum number of animals, not including natural
mortalities, that may be removed from a marine mammal stock while
allowing that stock to reach or maintain its optimum sustainable
population (as described in NMFS's SARs). While no mortality is
anticipated or authorized here, PBR and annual serious injury and
mortality from anthropogenic sources are included here as gross
indicators of the status of the species and other threats.
Marine mammal abundance estimates presented in this document
represent the total number of individuals that make up a given stock or
the total number estimated within a particular study or survey area.
NMFS's stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprises that stock. For some species, this geographic area may extend
beyond U.S. waters. All managed stocks in this region are assessed in
NMFS's U.S. Pacific and Alaska SARs (e.g., Carretta et al., 2020). All
values presented in Table 3 are the most recent available at the time
of publication and are available in the 2019 SARs (Carretta et al.,
2020, Muto et al., 2020).
[[Page 48210]]
Table 3--Species Proposed for Authorized Take
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ESA/ MMPA status; Stock abundance (CV,
Common name Scientific name Stock strategic (Y/N) Nmin, most recent PBR Annual M/
\a\ abundance survey) \b\ SI \c\
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Order Cetartiodactyla--Cetacea--Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
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Family Delphinidae:
Killer Whale.................... Orcinus orca........... West Coast Transient... -, -, N 243 \d\ (N/A, 243, 2.4 0
2009).
Family Phocoenidae (porpoises):
Harbor porpoise................. Phocoena phocoena...... Washington Inland -, -, N 11,233 (0.37, 8,308, 66 >=7.2
Waters. 2015).
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Order Carnivora--Superfamily Pinnipedia
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Family Otariidae (eared seals and
sea lions):
California Sea Lion............. Zalophus californianus. United States.......... -, -, N 257,606 (N/A, 233,515, 14,011 >321
2014).
Steller sea lion................ Eumetopias jubatus Eastern U.S............ -, -, N 43,201 \e\ (see SAR, 2,592 113
monteriensis. 43,201, 2017).
Family Phocidae (earless seals):
Harbor seal..................... Phoca vitulina......... Washington Inland -, -, N 1,088 (0.15, UNK, UNK 0.2
Waters, Hood Canal. 1999) \f\.
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\a\-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.
\b\-NMFS marine mammal stock assessment reports online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\c\-These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
commercial fisheries, ship strike). Annual mortality/serious injury (M/SI) often cannot be determined precisely and is in some cases presented as a
minimum value or range.
\d\-Based on counts of individual animals identified from photo-identification catalogues. Surveys for abundance estimates of these stocks are conducted
infrequently.
\e\-Best estimate of pup and non-pup counts, which have not been corrected to account for animals at sea during abundance surveys.
\f\-The abundance estimate for this stock is greater than eight years old and is therefore not considered current. PBR is considered undetermined for
this stock, as there is no current minimum abundance estimate for use in calculation. We nevertheless present the most recent abundance estimates, as
these represent the best available information for use in this document.
As indicated above, all five species (with five managed stocks) in
Table 3 temporally and spatially co-occur with the activity to the
degree that take is reasonably likely to occur, and we have proposed
authorizing it. While humpback whale, gray whale, Southern Resident
killer whale, Dall's porpoise, and bottlenose dolphin have been sighted
in the area, the temporal and spatial occurrence of these species is
such that take is not expected to occur, and they are not discussed
further beyond the explanation provided here. Humpback whales
(Megaptera novaeangliae) have been detected year-round in small numbers
in Puget Sound. In Hood Canal, after an absence of sightings for over
15 years, an individual was seen over a 1-week period in early 2012,
with additional 1-day sightings in 2015, 2016, and 2017 (Orca Network,
2019). However, these sightings are exceptions to the normal occurrence
of the species in Washington inland waters. Gray whales (Eschrichtius
robustus) have been infrequently documented in Hood Canal waters over
the past decade. There were five sightings in 2017 and one in 2018
(Orca Network, 2017, 2019). These sightings are an exception to the
normal seasonal occurrence of gray whales in Puget Sound feeding areas.
The Southern Resident killer whale stock is resident to the inland
waters of Washington state and British Columbia; however, it has not
been seen in Hood Canal in over 15 years. Dall's porpoise (Phocoenoides
dalli) was documented once in Hood Canal in 2009 and more recently once
in 2018 (Orca Network, 2019); however, Dall's porpoises are unlikely to
be present in Hood Canal. Bottlenose dolphin (Tursiops truncatus) were
documented in Hood Canal twice in 2018 (Orca Network, 2019); however,
bottlenose dolphins are unlikely to be present in Hood Canal.
Killer Whale
Killer whales in the project area are expected to be from the West
Coast Transient stock, which occurs from California through
southeastern Alaska with a preference for coastal waters of southern
Alaska and British Columbia (Krahn et al., 2002). Transient killer
whales in the Pacific Northwest spend most of their time along the
outer coast of British Columbia and Washington, but visit inland waters
in search of harbor seals, sea lions, and other prey.
Transients may occur in inland waters in any month (Orca Network,
2015). However, Morton (1990) found bimodal peaks in spring (March) and
fall (September to November) for transients on the northeastern coast
of British Columbia, and Baird and Dill (1995) found some transient
groups frequenting the vicinity of harbor seal haulouts around southern
Vancouver Island during August and September, which is the peak period
for pupping through post-weaning of harbor seal pups. Not all transient
groups were seasonal in these studies, and their movements appeared to
be unpredictable. From 2004-2010, transient killer whales occurred in
Washington inland waters most frequently in August-September with a
strong second peak in April-May (Houghton et al., 2015).
The number of West Coast Transient killer whales in Washington
inland waters at any one time was previously considered likely to be
fewer than 20 individuals (Wiles, 2004). Recent research suggests that
the transient killer whales use of inland waters increased from 2004
through 2010, with the trend likely due to increasing prey abundance
(Houghton et al., 2015). Many of the West Coast Transients in
Washington inland waters have been catalogued by photo identification.
Transient killer whales were observed for lengthy periods in Hood
Canal in 2003 (59 days) and 2005 (172 days) between the months of
January and July (London, 2006), but were not observed again until
March 2016 (Orca Network, 2016). Transient killer whales were observed
in Hood Canal on two days in
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March 2016, one day in April 2016, eight consecutive days in May 2016,
one day in 2017, 11 consecutive days in April 2018, and one day on two
additional occasions in 2018. Some of the sightings in 2016 and 2018
were in Dabob Bay (Orca Network, 2017, 2019). Killer whales were
historically documented in Hood Canal by sound recordings in 1958
(Ford, 1991), a photograph from 1973, sound recordings in 1995 (Unger,
1997), and anecdotal accounts of historical use. Long-term use of Hood
Canal is likely anomalous. The more typical use of Hood Canal appears
to be short-term occupancy for foraging in a small area, followed by
departure from Hood Canal.
Harbor Porpoise
Harbor porpoise in Puget Sound are expected to be from the
Washington Inland Waters stock. In Washington inland waters, harbor
porpoise are known to occur in the Strait of Juan de Fuca and the San
Juan Island area year-round (Calambokidis & Baird, 1994; Osmek et al.,
1996; Carretta et al., 2012). Harbor porpoises were historically one of
the most commonly observed marine mammals in Puget Sound (Scheffer &
Slipp, 1948); however, there was a significant decline in sightings
beginning in the 1940s (Everitt et al., 1979; Calambokidis et al.,
1992). Only a few sightings were reported between the 1970s and 1980s
(Calambokidis et al., 1992; Osmek et al., 1996; Suryan & Harvey, 1998),
and no harbor porpoise sightings were recorded during multiple ship and
aerial surveys conducted in Puget Sound (including Hood Canal) in 1991
and 1994 (Calambokidis et al., 1992; Osmek et al., 1996). Incidental
sightings of marine mammals during aerial bird surveys conducted as
part of the Puget Sound Ambient Monitoring Program (PSAMP) detected few
harbor porpoises in Puget Sound between 1992 and 1999 (Nysewander et
al., 2005). However, these sightings may have been negatively biased
due to the low elevation of the plane that may have caused an avoidance
behavior. Since 1999, PSAMP data, stranding data, and aerial surveys
conducted from 2013 to 2015 documented increasing numbers of harbor
porpoise in Puget Sound (Nysewander, 2005; WDFW, 2008; Jeffries, 2013;
Jefferson et al., 2016; Smultea et al., 2017).
Sightings in Hood Canal, north of the Hood Canal Bridge, have
increased in recent years (Calambokidis, 2010). During line-transect
vessel surveys conducted in the Hood Canal in 2011 for the Test Pile
Program near Naval Base Kitsap Bangor and Dabob Bay (HDR, 2012), an
average of six harbor porpoises were sighted per day in the deeper
waters.
Steller Sea Lion
Steller sea lions in the project area are expected to be from the
Eastern U.S. stock. The Eastern U.S. stock of Steller sea lions is
found along the coasts of southeast Alaska to northern California where
they occur at rookeries and numerous haulout locations along the
coastline (Jeffries et al., 2000; Scordino, 2006; NMFS, 2013). Along
the northern Washington coast, up to 25 pups are born annually
(Jeffries, 2013). Male Steller sea lions often disperse widely outside
of the breeding season from breeding rookeries in northern California
(St. George Reef) and southern Oregon (Rogue Reef) (Scordino, 2006;
Wright et al., 2010). Based on mark recapture sighting studies, males
migrate back into these Oregon and California locations from winter
feeding areas in Washington, British Columbia, and Alaska (Scordino,
2006).
In Washington, Steller sea lions use haulout sites primarily along
the outer coast from the Columbia River to Cape Flattery, as well as
along the Vancouver Island side of the Strait of Juan de Fuca (Jeffries
et al., 2000). A major winter haulout is located in the Strait of Juan
de Fuca at Race Rocks, British Columbia, Canada (Canadian side of the
Strait of Juan de Fuca) (Edgell and Demarchi, 2012). Numbers vary
seasonally in Washington with peak numbers present during the fall and
winter months and a decline in the summer months that corresponds to
the breeding season at coastal rookeries (approximately late May to
early June) (Jeffries et al., 2000). In Puget Sound, Jeffries (2012)
identified five winter haulout sites used by adult and subadult
(immature or pre-breeding animals) Steller sea lions, ranging from
immediately south of Port Townsend (near Admiralty Inlet) to Olympia in
southern Puget Sound (see Figure 4-1 of the Navy's application).
Numbers of animals observed at these sites ranged from a few to less
than 100 (Jeffries, 2012). In addition, Steller sea lions
opportunistically haul out on various navigational buoys in Admiralty
Inlet south through southern Puget Sound near Olympia (Jeffries, 2012).
Typically, one or two animals occur at a time on these buoys.
Steller sea lions have been seasonally documented in shore-based
surveys at Naval Base Kitsap Bangor in Hood Canal since 2008 with up to
15 individuals observed hauled out on submarines at Delta Pier (Navy,
2016, 2019). Navy surveys at Naval Base Kitsap Bangor indicate Steller
sea lions begin arriving in September and depart by the end of May
(Navy, 2016, 2019). Survey methods and frequency are detailed Appendix
A of the Navy's application.
California Sea Lion
Jeffries et al. (2000) and Jeffries (2012) identified dedicated,
regular haulouts used by adult and subadult California sea lions in
Washington inland waters. Main haulouts occur at Naval Base Kitsap
Bangor, Naval Base Kitsap Bremerton, and Naval Station Everett, as well
as in Rich Passage near Manchester, Seattle (Shilshole Bay), south
Puget Sound (Commencement Bay, Budd Inlet), and numerous navigation
buoys south of Whidbey Island to Olympia in south Puget Sound (Jeffries
et al., 2000; Jeffries, 2012) (Figure 4-1 of the Navy's application).
Race Rocks, British Columbia, Canada (Canadian side of the Strait of
Juan de Fuca) has been identified as a major winter haulout for
California sea lions (Edgell and Demarchi, 2012). California sea lions
are typically present most of the year except for mid-June through July
in Washington inland waters, with peak abundance numbers between
October and May (NMFS, 1997; Jeffries et al., 2000). California sea
lions are expected to forage within the area, following local prey
availability. During summer months and associated breeding periods, the
inland waters are not considered a high-use area by California sea
lions, as they are returning to rookeries in California waters.
However, California sea lions have been documented during shore-based
surveys at Naval Base Kitsap Bangor in Hood Canal since 2008 in all
survey months, with as many as 320 individuals observed at one time
(October 2018) hauled out on submarines at Delta Pier and on port
security barrier (PSB) floats (Navy, 2016, 2019; Appendix A of the
Navy's application). Relatively few individuals (<17 sighted per
survey) were present during these surveys from June through August.
Harbor Seal
Harbor seals are a coastal species, rarely found more than 12 mi
(19.3 km) from shore. They frequently occupy bays, estuaries, and
inlets. Individual seals have been observed several miles upstream in
coastal rivers (Baird, 2001). Ideal harbor seal habitat includes
haulout sites, areas providing shelter during breeding periods, and
areas with sufficient food (Bj[oslash]rge, 2002). Haulout areas can
include intertidal and subtidal rock outcrops, sandbars, sandy beaches,
peat banks in salt marshes, and man-
[[Page 48212]]
made structures such as log booms, docks, and recreational floats
(Wilson, 1978; Prescott, 1982; Schneider & Payne, 1983, Gilbert &
Guldager, 1998; Jeffries et al., 2000; Lambourn et al., 2010). Harbor
seals do not make extensive pelagic migrations, though some long
distance movement of tagged animals in Alaska (108 mi (174 km)) and
along the U.S. west coast (up to 342 mi (550 km)) have been recorded
(Brown & Mate, 1983; Womble & Gende, 2013). Harbor seals have also
displayed strong fidelity to haulout sites.
Harbor seals are the most common, widely distributed marine mammal
found in Washington marine waters and are frequently observed in the
nearshore marine environment. They occur year-round and breed in
Washington. Numerous harbor seal haulouts occur in Washington inland
waters. Haulouts include intertidal and subtidal rock outcrops,
beaches, reefs, sandbars, log booms, and floats. Numbers of individuals
at haulouts range from a few to between 100 and 500 individuals
(Jeffries et al., 2000).
Harbor seals are expected to occur year-round at Naval Base Kitsap
Bangor. In Hood Canal, where Kitsap Bangor is located, known haulouts
occur on the west side of Hood Canal at the mouth of the Dosewallips
River and on the western and northern shorelines in Dabob Bay located
approximately 8 mi (13 km) away from the Navy's installation. Vessel-
based surveys conducted from 2007 to 2010 at Kitsap Bangor, observed
harbor seals in every month of surveys (Agness & Tannenbaum, 2009;
Tannenbaum et al., 2009, 2011). Harbor seals were routinely seen during
marine mammal monitoring for two construction projects, the Test Pile
Project and EHW-2 construction projects (HDR, 2012; Hart Crowser, 2013,
2014, 2015). Small numbers of harbor seals have been documented hauling
out on the PSB floats, wavescreens at Carderock Pier, buoys, barges,
marine vessels, and logs (Agness and Tannenbaum, 2009; Tannenbaum et
al., 2009, 2011; Navy, 2016) and on man-made floating structures near
Keyport Bangor Dock and Delta Pier. Opportunistic surveys by a Naval
Facilities Engineering Command biologist in August and September 2016
recorded as many as 28 harbor seals hauled out under Marginal Wharf or
swimming in adjacent waters. On two occasions, four to six individuals
were observed hauled out near Delta Pier.
The Navy identified a few observations of harbor seal births or
neonates. In 2014, the Navy's knowledge of harbor seal births increased
due to increased pinniped surveys on the waterfront and increased
contact with waterfront personnel who have had lengthy careers at
Bangor (Navy, 2016). Known harbor seal births include one on the
Carderock wave screen in August 2011 and at least one on a small 10 by
10 ft (3 by 3 m) floating dock at EHW-2 in fall 2013, as reported by
EHW-2 construction crews, and afterbirth observed on a float at
Magnetic Silencing Facility with an unknown date. In addition, Navy
biologists learned that harbor seal pupping has occurred on a section
of the Service Pier since approximately 2001, according to the Port
Operations vessel crews. Harbor seal mother and pup sets were observed
in 2014 hauled out on the Carderock wavescreen and swimming in nearby
waters, and swimming near Delta Pier (Navy, 2016).
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
decibel (dB) threshold from the normalized composite audiograms, with
the exception for lower limits for low-frequency cetaceans where the
lower bound was deemed to be biologically implausible and the lower
bound from Southall et al. (2007) retained. Marine mammal hearing
groups and their associated hearing ranges are provided in Table 4.
Table 4--Marine Mammal Hearing Groups
[NMFS, 2018]
----------------------------------------------------------------------------------------------------------------
Hearing group Generalized hearing range *
----------------------------------------------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen whales)............... 7 Hz to 35 kHz.
Mid-frequency (MF) cetaceans (dolphins, toothed whales, 150 Hz to 160 kHz.
beaked whales, bottlenose whales).
High-frequency (HF) cetaceans (true porpoises, Kogia, river 275 Hz to 160 kHz.
dolphins, cephalorhynchid, Lagenorhynchus cruciger & L.
australis).
Phocid pinnipeds (PW) (underwater) (true seals)............ 50 Hz to 86 kHz.
Otariid pinnipeds (OW) (underwater) (sea lions and fur 60 Hz to 39 kHz.
seals).
----------------------------------------------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a composite (i.e., all species within the
group), where individual species' hearing ranges are typically not as broad. Generalized hearing range chosen
based on ~65 dB threshold from normalized composite audiogram, with the exception for lower limits for LF
cetaceans (Southall et al. 2007) and PW pinniped (approximation).
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt,
2013).
For more detail concerning these groups and associated frequency
ranges, please see NMFS (2018) for a review of available information.
Five marine mammal species (two cetacean and two pinniped (two otariid
and one phocid) species) have the reasonable potential to co-occur with
the proposed construction (Table 4). Of the cetacean species that may
be present, one is classified as a mid-frequency cetacean (i.e., killer
whale), and one is classified as a high-frequency cetacean (i.e.,
harbor porpoise).
[[Page 48213]]
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 section later in this document
includes a quantitative analysis of the number of individuals that are
expected to be taken by this activity. The Negligible Impact Analysis
and Determination section considers the content of this section, the
Estimated Take section, and the Proposed Mitigation section, to draw
conclusions regarding the likely impacts of these activities on the
reproductive success or survivorship of individuals and how those
impacts on individuals are likely to impact marine mammal species or
stocks.
Acoustic effects on marine mammals during the specified activity
can occur from vibratory and impact pile driving. The effects of
underwater noise from the Navy's proposed activities have the potential
to result in Level A and Level B harassment of marine mammals in the
action area.
Description of Sound Sources
The marine soundscape is comprised of both ambient and
anthropogenic sounds. Ambient sound is defined as the all-encompassing
sound in a given place and is usually a composite of sound from many
sources both near and far. The sound level of an area is defined by the
total acoustical energy being generated by known and unknown sources.
These sources may include physical (e.g., waves, wind, precipitation,
earthquakes, ice, atmospheric sound), biological (e.g., sounds produced
by marine mammals, fish, and invertebrates), and anthropogenic sound
(e.g., vessels, dredging, aircraft, construction).
The sum of the various natural and anthropogenic sound sources at
any given location and time--which comprise ``ambient'' or
``background'' sound--depends not only on the source levels (as
determined by current weather conditions and levels of biological and
shipping activity) but also on the ability of sound to propagate
through the environment. In turn, sound propagation is dependent on the
spatially and temporally varying properties of the water column and sea
floor, and is frequency-dependent. As a result of the dependence on a
large number of varying factors, ambient sound levels can be expected
to vary widely over both coarse and fine spatial and temporal scales.
Sound levels at a given frequency and location can vary by 10-20 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 vibratory pile
removal. The sounds produced by these activities fall into one of two
general sound types: Impulsive and non-impulsive. Impulsive sounds
(e.g., explosions, gunshots, sonic booms, impact pile driving) are
typically transient, brief (less than 1 second), broadband, and consist
of high peak sound pressure with rapid rise time and rapid decay (ANSI
1986; NIOSH 1998; ANSI 2005; NMFS 2018a). Non-impulsive sounds (e.g.,
aircraft, machinery operations such as drilling or dredging, vibratory
pile driving, and active sonar systems) can be broadband, narrowband or
tonal, brief or prolonged (continuous or intermittent), and typically
do not have the high peak sound pressure with raid rise/decay time that
impulsive sounds do (ANSI 1995; NIOSH 1998; NMFS 2018a). The
distinction between these two sound types is important because they
have differing potential to cause physical effects, particularly with
regard to hearing (e.g., Ward 1997 in Southall et al. 2007).
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 sound
pressure levels (SPLs) may be 180 dB or greater, but are generally 10
to 20 dB lower than SPLs generated during impact pile driving of the
same-sized pile (Oestman et al. 2009). Rise time is slower, reducing
the probability and severity of injury, and sound energy is distributed
over a greater amount of time (Nedwell and Edwards 2002; Carlson et al.
2005).
The likely or possible impacts of the Navy'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.
Acoustic Impacts
The introduction of anthropogenic noise into the aquatic
environment from pile driving and removal is the primary means by which
marine mammals may be harassed from the Navy'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 removal 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 removal
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 recovery (seconds to minutes or hours to days), the
frequency range of the exposure (i.e., spectral content), the
[[Page 48214]]
hearing and vocalization frequency range of the exposed species
relative to the signal's frequency spectrum (i.e., how an animal uses
sound within the frequency band of the signal; e.g., Kastelein et al.
2014), and the overlap between the animal and the source (e.g.,
spatial, temporal, and spectral).
Permanent Threshold Shift (PTS)--NMFS defines PTS as a permanent,
irreversible increase in the threshold of audibility at a specified
frequency or portion of an individual's hearing range above a
previously established reference level (NMFS 2018). Available data from
humans and other terrestrial mammals indicate that a 40 dB threshold
shift approximates PTS onset (see Ward et al. 1958, 1959; Ward 1960;
Kryter et al. 1966; Miller 1974; Ahroon et al. 1996; Henderson et al.
2008). PTS levels for marine mammals are estimates, as with the
exception of a single study unintentionally inducing PTS in a harbor
seal (Kastak et al. 2008), there are no empirical data measuring PTS in
marine mammals largely due to the fact that, for various ethical
reasons, experiments involving anthropogenic noise exposure at levels
inducing PTS are not typically pursued or authorized (NMFS 2018).
Temporary Threshold Shift (TTS)--TTS is a temporary, reversible
increase in the threshold of audibility at a specified frequency or
portion of an individual's hearing range above a previously established
reference level (NMFS 2018). Based on data from cetacean TTS
measurements (see Southall et al. 2007), a TTS of 6 dB is considered
the minimum threshold shift clearly larger than any day-to-day or
session-to-session variation in a subject's normal hearing ability
(Schlundt et al. 2000; Finneran et al. 2000, 2002). As described in
Finneran (2015), marine mammal studies have shown the amount of TTS
increases with cumulative sound exposure level (SELcum) in an
accelerating fashion: At low exposures with lower SELcum, the amount of
TTS is typically small and the growth curves have shallow slopes. At
exposures with higher SELcum, the growth curves become steeper and
approach linear relationships with the noise SEL.
Depending on the degree (elevation of threshold in dB), duration
(i.e., recovery time), and frequency range of TTS, and the context in
which it is experienced, TTS can have effects on marine mammals ranging
from discountable to serious (similar to those discussed in auditory
masking, below). For example, a marine mammal may be able to readily
compensate for a brief, relatively small amount of TTS in a non-
critical frequency range that takes place during a time when the animal
is traveling through the open ocean, where ambient noise is lower and
there are not as many competing sounds present. Alternatively, a larger
amount and longer duration of TTS sustained during 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, 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 and vibratory pile
driving. For this project, these activities would not occur at the same
time and there would be pauses in activities producing the sound during
each day. Given these pauses and that many marine mammals are likely
moving through the ensonified area and not remaining for extended
periods of time, the potential for TS declines.
Behavioral Harassment--Exposure to noise from pile driving and
removal also has the potential to behaviorally disturb marine mammals.
Available studies show wide variation in response to underwater sound;
therefore, it is difficult to predict specifically how any given sound
in a particular instance might affect marine mammals perceiving the
signal. If a marine mammal does react briefly to an underwater sound by
changing its behavior or moving a small distance, the impacts of the
change are unlikely to be significant to the individual, let alone the
stock or population. However, if a sound source displaces marine
mammals from an important feeding or breeding area for a prolonged
period, impacts on individuals and populations could be significant
(e.g., Lusseau & 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,
duration, and temporal pattern of signal presentation, as well as
differences in species sensitivity, are likely contributing factors to
differences in
[[Page 48215]]
response in any given circumstance (e.g., Croll et al. 2001; Nowacek et
al. 2004; Madsen et al. 2006; Yazvenko et al. 2007). A determination of
whether foraging disruptions incur fitness consequences would require
information on or estimates of the energetic requirements of the
affected individuals and the relationship between prey availability,
foraging effort and success, and the life history stage of the animal.
Stress responses--An animal's perception of a threat may be
sufficient to trigger stress responses consisting of some combination
of behavioral responses, autonomic nervous system responses,
neuroendocrine responses, or immune responses (e.g., Seyle 1950; Moberg
2000). In many cases, an animal's first and sometimes most economical
(in terms of energetic costs) response is behavioral avoidance of the
potential stressor. Autonomic nervous system responses to stress
typically involve changes in heart rate, blood pressure, and
gastrointestinal activity. These responses have a relatively short
duration and may or may not have a significant long-term effect on an
animal's fitness.
Neuroendocrine stress responses often involve the hypothalamus-
pituitary-adrenal system. Virtually all neuroendocrine functions that
are affected by stress--including immune competence, reproduction,
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been
implicated in failed reproduction, altered metabolism, reduced immune
competence, and behavioral disturbance (e.g., Moberg 1987; Blecha
2000). Increases in the circulation of glucocorticoids are also equated
with stress (Romano et al., 2004).
The primary distinction between stress (which is adaptive and does
not normally place an animal at risk) and ``distress'' is the cost of
the response. During a stress response, an animal uses glycogen stores
that can be quickly replenished once the stress is alleviated. In such
circumstances, the cost of the stress response would not pose serious
fitness consequences. However, when an animal does not have sufficient
energy reserves to satisfy the energetic costs of a stress response,
energy resources must be diverted from other functions. This state of
distress will last until the animal replenishes its energetic reserves
sufficient to restore normal function.
Relationships between these physiological mechanisms, animal
behavior, and the costs of stress responses are well-studied through
controlled experiments and for both laboratory and free-ranging animals
(e.g., Holberton et al., 1996; Hood et al., 1998; Jessop et al., 2003;
Krausman et al., 2004; Lankford et al., 2005). Stress responses due to
exposure to anthropogenic sounds or other stressors and their effects
on marine mammals have also been reviewed (Fair and Becker 2000; Romano
et al., 2002b) and, more rarely, studied in wild populations (e.g.,
Romano et al., 2002a). For example, Rolland et al. (2012) found that
noise reduction from reduced ship traffic in the Bay of Fundy was
associated with decreased stress in North Atlantic right whales. These
and other studies lead to a reasonable expectation that some marine
mammals will experience physiological stress responses upon exposure to
acoustic stressors and that it is possible that some of these would be
classified as ``distress.'' In addition, any animal experiencing TTS
would likely also experience stress responses (NRC, 2003), however
distress is an unlikely result of this project based on observations of
marine mammals during previous, similar projects in the area.
Masking--Sound can disrupt behavior through masking, or interfering
with, an animal's ability to detect, recognize, or discriminate between
acoustic signals of interest (e.g., those used for intraspecific
communication and social interactions, prey detection, predator
avoidance, navigation) (Richardson et al. 1995). Masking occurs when
the receipt of a sound is interfered with by another coincident sound
at similar frequencies and at similar or higher intensity, and may
occur whether the sound is natural (e.g., snapping shrimp, wind, waves,
precipitation) or anthropogenic (e.g., pile driving, shipping, sonar,
seismic exploration) in origin. The ability of a noise source to mask
biologically important sounds depends on the characteristics of both
the noise source and the signal of interest (e.g., signal-to-noise
ratio, temporal variability, direction), in relation to each other and
to an animal's hearing abilities (e.g., sensitivity, frequency range,
critical ratios, frequency discrimination, directional discrimination,
age or TTS hearing loss), and existing ambient noise and propagation
conditions. Masking of natural sounds can result when human activities
produce high levels of background sound at frequencies important to
marine mammals. Conversely, if the background level of underwater sound
is high (e.g., on a day with strong wind and high waves), an
anthropogenic sound source would not be detectable as far away as would
be possible under quieter conditions and would itself be masked.
Airborne Acoustic Effects--Pinnipeds that occur near the project
site could be exposed to airborne sounds associated with pile driving
and removal that have the potential to cause behavioral harassment,
depending on their distance from pile driving activities. Cetaceans are
not expected to be exposed to airborne sounds that would result in
harassment as defined under the MMPA.
Airborne noise would primarily be an issue for pinnipeds that are
swimming or hauled out near the project site within the range of noise
levels exceeding the acoustic thresholds. We recognize that pinnipeds
in the water could be exposed to airborne sound that may result in
behavioral harassment when looking with their heads above water. Most
likely, airborne sound would cause behavioral responses similar to
those discussed above in relation to underwater sound. For instance,
anthropogenic sound could cause 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,
authorization of incidental take resulting from airborne sound for
pinnipeds is not warranted, and airborne sound is not discussed further
here.
Marine Mammal Habitat Effects
The Navy's construction activities could have localized, temporary
impacts on marine mammal habitat by increasing in-water sound pressure
levels and slightly decreasing water quality. Construction activities
are of short duration and would likely have temporary impacts on marine
mammal habitat through increases in underwater sound. Increased noise
levels may affect acoustic habitat (see masking discussion above) and
adversely affect marine mammal prey in the vicinity of the project area
(see discussion below). During impact and vibratory pile driving,
elevated levels of underwater noise would ensonify Hood Canal where
both fish and mammals may occur and could affect foraging success.
Additionally, marine mammals may
[[Page 48216]]
avoid the area during construction, however, displacement due to noise
is expected to be temporary and is not expected to result in long-term
effects to the individuals or populations.
A temporary and localized increase in turbidity near the seafloor
would occur in the immediate area surrounding the area where piles are
installed (and removed in the case of the temporary piles). The
sediments on the sea floor will be disturbed during pile driving;
however, suspension will be brief and localized and is unlikely to
measurably affect marine mammals or their prey in the area. In general,
turbidity associated with pile installation is localized to about a 25-
foot (7.6-meter) radius around the pile (Everitt et al. 1980).
Cetaceans are not expected to be close enough to the pile driving areas
to experience effects of turbidity, and any pinnipeds could avoid
localized areas of turbidity. Therefore, we expect the impact from
increased turbidity levels to be discountable to marine mammals and do
not discuss it further.
In-Water Construction Effects on Potential Foraging Habitat
The proposed activities would not result in permanent impacts to
habitats used directly by marine mammals except for the actual
footprint of the project. The total seafloor area affected by pile
installation and removal is a very small area compared to the vast
foraging area available to marine mammals in Hood Canal.
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 we anticipate a rapid return to normal recruitment,
distribution and behavior. Any behavioral avoidance by fish of the
disturbed area would still leave large areas of fish and marine mammal
foraging habitat in the nearby vicinity in Hood Canal.
Effects on Potential Prey
Sound may affect marine mammals through impacts on the abundance,
behavior, or distribution of prey species (e.g., fish). Marine mammal
prey varies by species, season, and location. Here, we describe studies
regarding the effects of noise on known marine mammal prey.
Fish utilize the soundscape and components of sound in their
environment to perform important functions such as foraging, predator
avoidance, mating, and spawning (e.g., Zelick et al., 1999; Fay, 2009).
Depending on their hearing anatomy and peripheral sensory structures,
which vary among species, fishes hear sounds using pressure and
particle motion sensitivity capabilities and detect the motion of
surrounding water (Fay et al., 2008). The potential effects of noise on
fishes depends on the overlapping frequency range, distance from the
sound source, water depth of exposure, and species-specific hearing
sensitivity, anatomy, and physiology. Key impacts to fishes may include
behavioral responses, hearing damage, barotrauma (pressure-related
injuries), and mortality.
Fish react to sounds which are especially strong and/or
intermittent low-frequency sounds, and behavioral responses such as
flight or avoidance are the most likely effects. Short duration, sharp
sounds can cause overt or subtle changes in fish behavior and local
distribution. The reaction of fish to noise depends on the
physiological state of the fish, past exposures, motivation (e.g.,
feeding, spawning, migration), and other environmental factors.
Hastings and Popper (2005) identified several studies that suggest fish
may relocate to avoid certain areas of sound energy. Additional studies
have documented effects of pile driving on fish, although several are
based on studies in support of large, multiyear bridge construction
projects (e.g., Scholik and Yan, 2001, 2002; Popper and Hastings,
2009). Several studies have demonstrated that impulse sounds might
affect the distribution and behavior of some fishes, potentially
impacting foraging opportunities or increasing energetic costs (e.g.,
Fewtrell and McCauley, 2012; Pearson et al., 1992; Skalski et al.,
1992; Santulli et al., 1999; Paxton et al., 2017). However, some
studies have shown no or slight reaction to impulse sounds (e.g., Pena
et al., 2013; Wardle et al., 2001; Jorgenson and Gyselman, 2009; Cott
et al., 2012).
SPLs of sufficient strength have been known to cause injury to fish
and fish mortality. However, in most fish species, hair cells in the
ear continuously regenerate and loss of auditory function likely is
restored when damaged cells are replaced with new cells. Halvorsen et
al. (2012a) showed that a TTS of 4-6 dB was recoverable within 24 hours
for one species. Impacts would be most severe when the individual fish
is close to the source and when the duration of exposure is long.
Injury caused by barotrauma can range from slight to severe and can
cause death, and is most likely for fish with swim bladders. Barotrauma
injuries have been documented during controlled exposure to impact pile
driving (Halvorsen et al., 2012b; Casper et al., 2013).
The most likely impact to fish from pile driving activities at the
project areas would be temporary behavioral avoidance of the area. The
duration of fish avoidance of an area after pile driving stops is
unknown, but a rapid return to normal recruitment, distribution and
behavior is anticipated.
The area impacted by the project is relatively small compared to
the available habitat in the remainder of Hood Canal. 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. Additionally, as noted previously, the Navy will adhere to
the IWWW for pile extraction and installation (July 16 to January 15)
to reduce potential effects to salmonids, including juvenile ESA-listed
salmonids. As described in the preceding, the potential for the Navy's
construction to affect the availability of prey to marine mammals or to
meaningfully impact the quality of physical or acoustic habitat is
considered to be insignificant.
Estimated Take
This section provides an estimate of the number of incidental takes
proposed for authorization through this IHA, which will inform both
NMFS's 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 acoustic sources (i.e., vibratory and impact pile driving) 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 phocids, because
predicted auditory injury zones are larger than for mid-frequency
cetaceans and otariids, and Navy expects that protected species
observers (PSOs) will not be able to effectively observe the entire
Level A harassment zone due to
[[Page 48217]]
the numerous docks in the area. Auditory injury is unlikely to occur
for mid-frequency cetaceans, high-frequency cetaceans, and otariids.
The proposed mitigation and monitoring measures are expected to
minimize the severity of the 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 more detail and present the proposed take
estimate.
Acoustic Thresholds
NMFS recommends the use of acoustic thresholds that identify the
received level of underwater sound above which exposed marine mammals
would be reasonably expected to be behaviorally harassed (equated to
Level B harassment) or to incur PTS of some degree (equated to Level A
harassment).
Level B Harassment 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.
Navy's proposed activity includes the use of continuous (vibratory
pile driving) 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) (Technical Guidance, 2018) identifies dual
criteria to assess auditory injury (Level A harassment) to five
different marine mammal groups (based on hearing sensitivity) as a
result of exposure to noise from two different types of sources
(impulsive or non-impulsive). Navy's proposed activity includes the use
of impulsive (impact pile driving) and non-impulsive (vibratory pile
driving) sources.
These thresholds are provided in the table below. The references,
analysis, and methodology used in the development of the thresholds are
described in NMFS 2018 Technical Guidance, which may be accessed at
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.
Table 5--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
PTS onset acoustic thresholds * (received level)
Hearing group ------------------------------------------------------------------------
Impulsive Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans........... Cell 1: Lpk,flat: 219 dB; Cell 2: LE,LF,24h: 199 dB.
LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans........... Cell 3: Lpk,flat: 230 dB; Cell 4:
LE,MF,24h: 185 dB. LE,MF,24h: 198 dB.
High-Frequency (HF) Cetaceans.......... Cell 5: Lpk,flat: 202 dB; Cell 6: LE,HF,24h: 173 dB.
LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW).................. Cell 7: Lpk,flat: 218 dB; Cell 8:
(Underwater)........................... LE,PW,24h: 185 dB. LE,PW,24h: 201 dB.
Otariid Pinnipeds (OW)................. Cell 9: Lpk,flat: 232 dB; Cell 10: LE,OW,24h: 219 dB.
(Underwater)........................... LE,OW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [mu]Pa, and cumulative sound exposure level (LE) has
a reference value of 1[mu]Pa\2\s. In this Table, thresholds are abbreviated to reflect American National
Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as incorporating
frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript ``flat'' is
being included to indicate peak sound pressure should be flat weighted or unweighted within the generalized
hearing range. The subscript associated with cumulative sound exposure level thresholds indicates the
designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds) and
that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could be
exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible, it
is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
exceeded.
Ensonified Area
Here, we describe operational and environmental parameters of the
activity that will feed into identifying the area ensonified above the
acoustic thresholds, which include source levels and transmission loss
coefficient.
The 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 and
vibratory pile driving and removal). The largest calculated Level B
harassment zone is 11.7 km (7.3 mi) from the
[[Page 48218]]
source, with an area of 49.1 km\2\ (18.9 mi\2\).
The source levels were derived from the Navy's document titled
``Proxy Source Sound Levels and Potential Bubble Curtain Attenuation
for Acoustic Modeling of Nearshore Marine Pile Driving at Navy
Installations in Puget Sound'' (Navy 2015a). In that document, the Navy
reviewed relevant data available for various types and sizes of piles
typically used for pile driving and recommend proxy source values for
Navy installations in Puget Sound. This document is included as
Appendix B in the Navy's application. Source levels for each pile size
and activity are presented in Table 6.
The Navy will implement bubble curtains (e.g. pneumatic barrier
typically comprised of hosing or PVC piping that disrupts underwater
noise propagation; see Proposed Mitigation section below) during impact
pile driving, with the possible exception of short periods when the
device is turned off to test the effectiveness of the noise attenuation
device. We have reduced the source level for these activities by 8 dB
in consideration of site-specific measurements of source level
reduction with use of bubble curtains (Navy, 2015). These reductions
ranged from 8 dB to 10 dB. In their analysis, the Navy averaged
different metrics for the same pile size. NMFS independently calculated
the average source level reduction, averaging reductions of the same
metric (ex: SPLrms) reported for both 36-in and 48-in piles. As such,
NMFS calculated an SEL reduction of 8.5 dB, an SPLrms reduction of 8
dB, and an SPLpk reduction of 10 dB. Therefore, given that the site-
specific 8 dB reduction proposed by the Navy is the same or lower than
the result of NMFS's site-specific calculation, NMFS preliminarily
accepted Navy's proposal to use an 8 dB reduction during impact pile
driving.
Table 6--Project Sound Source Levels (Navy, 2015)
----------------------------------------------------------------------------------------------------------------
Source level @10m
Pile type and size Installation method -----------------------------------------------
dB RMS dB Peak dB SEL
----------------------------------------------------------------------------------------------------------------
36-inch Steel......................... Impact.................. a 194 a 211 a 181
24-inch Steel......................... Vibratory............... 161
30-inch Steel......................... ........................ .............. .............. 166
36-inch Steel......................... ........................ .............. .............. 166
----------------------------------------------------------------------------------------------------------------
a Unattenuated.
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
R1 = the distance of the modeled SPL from the driven
pile, and
R2 = the distance from the driven pile of the initial
measurement
Absent site-specific acoustical monitoring with differing measured
transmission loss, a practical spreading value of 15 is used as the
transmission loss coefficient in the above formula. Site-specific
transmission loss data for the TPP pier site are not available,
therefore the default coefficient of 15 is used to determine the
distances to the Level A and Level B harassment thresholds.
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, NMFS User Spreadsheet predicts the distance at which, if a
marine mammal remained at that distance the whole duration of the
activity, it would incur PTS. Inputs used in the User Spreadsheet, and
the resulting isopleths are reported below.
Table 7--User Spreadsheet Input Parameters Used for Calculating Level A Harassment Isopleths
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Weighting Distance from
factor Number of Duration to Number of Propagation source level
Pile size and installation method Spreadsheet tab used adjustment Source level piles within drive a single strikes per (xLogR) measurement
(kHz) 24-h period pile (minutes) pile (meters)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
36-inch Steel-Impact.................... E.1) Impact pile driving.. 2 173 dB SELa............... 4 30 400 15 10
24-inch Steel-Vibratory................. A.1) Vibratory pile 2.5 161 dB RMS................ b 5 60
driving.
30-inch Steel-Vibratory................. 166 dB RMS
36-inch Steel-Vibratory................. 166 dB RMS
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
a This source level includes an 8dB reduction from the use of a bubble curtain.
b The Navy expects to install only 4 piles per day using a vibratory hammer; however, for purposes of calculating the Level A harassment zones, they have conservatively assumed that they may
install 5 piles per day.
[[Page 48219]]
Table 8--Calculated Distances to Level A and Level B Harassment Isopleths
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Distance to level A harassment isopleth (m) Distance to
------------------------------------------------------------------------------------------------------------------- level B
Pile type and size Installation method harassment
LF cetacean MF cetacean HF cetacean Phocid Otariid isopleth (m)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
36-inch Steel....................... Impact................. 294 (1m pk)............... 11 351 (14m pk).............. 158 (1m pk).............. 12 541
24-inch Steel....................... Vibratory.............. 20........................ 2 30........................ 12....................... 1 5,400
30-inch Steel....................... 43........................ 4 64........................ 26....................... 2 11,700
36-inch Steel....................... 43........................ 4 64........................ 26....................... 2 11,700
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
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. We describe how the information provided above is brought
together to produce a quantitative take estimate.
Killer Whale
Transient killer whales occasionally occur throughout Puget Sound
but are rare in Hood Canal. In Puget Sound, they are typically observed
in small groups with an average group size of six individuals
(Houghton, 2012). Based on this Puget Sound average, the Navy estimated
that two groups of six whales may occur within the Level B harassment
zone during construction each year, and has requested 12 Level B
harassment takes of killer whale for Year 1 and Year 2. NMFS concurs
with this estimate, and proposes to authorize 12 Level B harassment
takes of killer whale in each year. Given the estimated number of
construction days in Year 2 (10 days), NMFS expects that 12 Level B
harassment takes is a conservative estimate for Year 2, but is
appropriate given that it accounts for the occurrence of just two
groups.
The largest Level A harassment zone for mid-frequency cetaceans
extends 11 m from the source during impact pile driving of 36-inch
steel piles (Table 8). Given the small size of the Level A harassment
zones, we would not expect Level A harassment take of killer whales to
occur. Additionally, the Navy is planning to implement a 355 m shutdown
zone for all cetaceans during that activity (Table 10). These shutdown
zones are expected to eliminate the potential for Level A harassment
take of killer whale. Therefore, NMFS does not propose to authorize
Level A harassment take of killer whale in Year 1 or Year 2.
Harbor Porpoise
Harbor porpoises may be present in all major regions of Puget Sound
throughout the year. Aerial surveys conducted throughout 2013 to 2015
in Puget Sound indicated density in Puget Sound was 0.91 individuals/sq
km) (95 percent CI = 0.72-1.10, all seasons pooled) and density in Hood
Canal was 0.44/sq km (95 percent CI = 0.29-0.75, all seasons pooled)
(Smultea et al., 2017). Mean group size of harbor porpoises in Puget
Sound in the 2013-2015 surveys was 1.7 in Hood Canal.
In consideration of the harbor porpoise take estimate, the Navy
conservatively assumed that vibratory installation of 36-inch piles
would occur on every in-water work day, given that that activity
resulted in the largest Level B harassment zone. The Navy estimated
Level B harassment takes of harbor porpoise by multiplying the 0.44
animals/km\2\ by 49.1 km\2\ (estimated Level B harassment zone during
vibratory driving of 36-inch piles) by the number of in-water workdays
during each year. Therefore, during Year 1, the Navy estimated 1,728
Level B harassment takes (0.44 animals/km\2\ x 49.1km\2\ x 80 days).
During Year 2, the Navy estimated 216 Level B harassment takes (0.44
animals/km\2\ x 49.1 km\2\ x 10 days). NMFS concurs with this approach,
and proposes to authorize 1,728 Level B harassment takes of harbor
porpoise in Year 1, and 216 Level B harassment takes of harbor porpoise
in Year 2.
The largest Level A harassment zone for high-frequency cetaceans
extends 351 m from the source during impact pile driving of 36-inch
steel piles (Table 8). The Navy is planning to implement a 355 m
shutdown zone for all cetaceans during that activity (Table 10), which
incorporates the entire Level A harassment zone, and the 14 m peak PTS
isopleth (Table 8). Therefore, the shutdown zones are expected to
eliminate the potential for Level A harassment take of harbor porpoise,
and NMFS does not propose to authorize Level A harassment take of
harbor porpoise.
Steller Sea Lion
Steller sea lions are routinely seen hauled out from mid-September
through May on submarines at Naval Base Kitsap Bangor, with a maximum
haulout count of 15 individuals in November 2018. Because the daily
average number of Steller sea lions hauled out at Kitsap Bangor has
increased since 2013 compared to prior years, the Navy relied on
monitoring data from July 2012 through February 2019 to determine the
average of the maximum count of hauled out Steller sea lions for each
month in the IWWW (Navy, 2016, 2019). While pinnipeds may haul out
longer than the period required for pile driving, therefore not being
exposed to underwater sound, the Navy conservatively assumed that any
Steller sea lion that hauls out at Kitsap Bangor may enter the Level B
harassment zone each day during pile driving.
For each in-water work month, the Navy averaged the maximum number
of hauled out Steller sea lions observed in a single survey at Kitsap
Bangor during that month for each year (2008 to 2019; see Appendix A of
the Navy's application). The Navy then averaged these monthly averages
across the entire in-water work period, resulting in a maximum average
of four Steller sea lions hauled out per day. The Navy assumed that
each of these animals may enter the Level B harassment zone on each in-
water work day. Therefore, the Navy requested 320 Level B harassment
takes of Steller sea lion in Year 1 (4 Steller sea lions x 80 in-water
work days), and 40 Level B harassment takes of Steller sea lions during
Year 2 (4 Steller sea lions x 10 in-water work days). NMFS concurs with
this approach and proposes to authorize 320 Level B harassment takes of
Steller sea lion during Year 1, and 40 Level B harassment takes of
Steller sea lion during Year 2.
The largest Level A harassment zone for otariids extends 11 m from
the source during impact pile driving of 36-inch steel piles (Table 8).
Given the small size of the Level A harassment zones, we would not
expect Level A harassment take of Steller sea lion to occur.
Additionally, the Navy is planning to implement a 15m shutdown zone
during that activity (Table 10). The Navy's shutdown zones are expected
to eliminate the potential for Level A
[[Page 48220]]
harassment take of Steller sea lion. Therefore, NMFS does not propose
to authorize Level A harassment take of Steller sea lion.
California sea lion
From August through June, California sea lions routinely haul out
on the PSB floats and submarines at Kitsap Bangor. For each in-water
work month, the Navy averaged the maximum number of hauled out
California sea lions observed in a single survey at Kitsap Bangor
during that month for each year (2008 to 2019; see Appendix A of the
Navy's application). The Navy then averaged these monthly averages
across the entire in-water work period, resulting in a maximum average
of 54 California sea lions hauled out per day. The daily average number
of California sea lions hauled out at Kitsap Bangor has increased since
2013 compared to prior years. Therefore, the Navy relied on monitoring
data from July 2012 through February 2019 to determine the average of
the maximum count (Navy, 2016, 2019).
While pinnipeds may haul out longer than the period required for
pile driving, therefore not being exposed to underwater sound, the Navy
conservatively assumed that any California sea lion hauled out at
Kitsap Bangor may swim into the Level B harassment zone on each pile
driving day. Therefore, the Navy requested 4,320 Level B harassment
takes of California sea lion in Year 1 (54 California sea lions x 80
in-water work days), and 540 Level B harassment takes of California sea
lions during Year 2 (54 California sea lions x 10 in-water work days).
NMFS concurs with this approach and proposes to authorize 4,320 Level B
harassment takes of California sea lion during Year 1, and 540 Level B
harassment takes of California sea lion during Year 2.
The largest Level A harassment zone for otariids extends 11 m from
the source during impact pile driving of 36-inch steel piles (Table 8).
Given the small size of the Level A harassment zones, we would not
expect Level A harassment take of California sea lion to occur.
Additionally, the Navy is planning to implement a 15 m shutdown zone
during that activity (Table 10). The Navy's shutdown zones are expected
to eliminate the potential for Level A harassment take of California
sea lion. Therefore, NMFS does not propose to authorize Level A
harassment take of California sea lion.
Harbor Seal
The harbor seal is the only species of marine mammal that is
consistently abundant and considered resident in Hood Canal (Jeffries
et al., 2003). The closest major haulouts to Kitsap Bangor that are
regularly used by harbor seals are the mouth of the Dosewallips River
located approximately 13.2 km (8.2 mi) away. No harbor seal haulouts
were seen on the shoreline opposite Kitsap Bangor (the east-side of the
Toandos Peninsula) during 2015 and 2016 beach seine surveys. A small
haulout occurs at Kitsap Bangor under Marginal Wharf and small numbers
of harbor seals are known to routinely haul out around the Carderock
pier (see Figure 1-2 of the Navy's application). Boat-based surveys and
monitoring indicate that harbor seals regularly swim in the waters at
Kitsap Bangor. Hauled out adults, mother/pup pairs, and neonates have
been documented occasionally but quantitative data are limited.
Incidental surveys in August and September 2016 recorded as many as 28
harbor seals hauled out under Marginal Wharf or swimming in adjacent
waters. Assuming a few other individuals may be present elsewhere on
the Kitsap Bangor waterfront, the Navy estimates that 35 harbor seals
may be present during summer and early fall months. Based on haulout
survey data from Naval Station Everett (Navy, 2016), the number of
harbor seals present at Kitsap Bangor is likely to be lower in late
fall and winter months.
The Navy conservatively assumed that each of the estimated 35
harbor seals may occur within the Level B harassment zone on each pile
driving day. Therefore, the Navy requested 2,800 Level B harassment
takes of harbor seal in Year 1 (35 harbor seals x 80 in-water work
days), and 350 Level B harassment takes of harbor seal during Year 2
(35 harbor seals x 10 in-water work days). NMFS concurs with this
approach and proposes to authorize 2,800 Level B harassment takes of
harbor seal during Year 1, and 350 Level B harassment takes of harbor
seal during Year 2.
The largest Level A harassment zone for phocids during Year 1
extends 158 m during impact installation of 36-inch steel piles (Table
8). The Navy is planning to implement a 160 m shutdown zone during that
activity (Table 10), which incorporates the entire Level A harassment
zone, and the 1 m peak PTS isopleth (Table 8). However, the Navy
estimates that some harbor seals may enter, and remain inside the Level
A harassment zone undetected by PSOs for a period long enough to be
taken by Level A harassment during Year 1. NMFS concurs, and proposes
to authorize 20 Level A harassment takes of harbor seal in Year 1 (1
harbor seal for every 4 in-water work days).
During Year 2, the largest Level A harassment zone for phocids
extends 26 m from the source during vibratory pile driving of 30 and
36-inch steel piles, as no impact pile driving is planned for Year 2.
The Navy expects to be able to effectively monitor this zone and
implement a 30 m shutdown zone. Therefore, the Navy does not expect
Level A harassment take to occur during Year 2. NMFS concurs that the
Navy's shutdown zones are expected to eliminate the potential for Level
A harassment take of harbor seal in Year 2, and does not propose to
authorize Level A harassment take of harbor seal in Year 2.
Table 9--Estimated Take by Level A and Level B Harassment, by Species and Stock
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Year 1 Year 2
------------------------------------------------------------------------------------------------------
Level B
Species Stock Stock Abundance Level A Level B Total take (percent of harassment Total take (percent of
harassment harassment stock) take (percent stock)
take take of stock)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Killer whale........................ West Coast Transient... 243....................... 0 12 12 (4.9).................. 12 12 (4.9)
Harbor porpoise..................... Washington Inland 11,233.................... 1,728 1,728 (15.4).............. 216 216 (1.9)
Waters.
Steller sea lion.................... Eastern U.S............ 43,201.................... 320 320 (0.7)................. 40 40 (0.1)
California sea lion................. United States.......... 257,606................... 4,320 4,320 (1.7)............... 540 540 (0.2)
[[Page 48221]]
Harbor seal......................... Washington Inland Unknown................... 20 2,800 2,820 (Unknown)........... 350 350 (Unknown)
Waters, Hood Canal.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Proposed Mitigation
In order to issue an IHA under Section 101(a)(5)(D) of the MMPA,
NMFS must set forth the permissible methods of taking pursuant to the
activity, and other means of effecting the least practicable impact on
the species or stock and its habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance, and on
the availability of the species or stock for taking for certain
subsistence uses (latter not applicable for this action). NMFS
regulations require applicants for incidental take authorizations to
include information about the availability and feasibility (economic
and technological) of equipment, methods, and manner of conducting the
activity or other means of effecting the least practicable adverse
impact upon the affected species or stocks and their habitat (50 CFR
216.104(a)(11)).
In evaluating how mitigation may or may not be appropriate to
ensure the least practicable adverse impact on species or stocks and
their habitat, as well as subsistence uses where applicable, we
carefully consider two primary factors:
(1) The manner in which, and the degree to which, the successful
implementation of the measure(s) is expected to reduce impacts to
marine mammals, marine mammal species or stocks, and their habitat.
This considers the nature of the potential adverse impact being
mitigated (likelihood, scope, range). It further considers the
likelihood that the measure will be effective if implemented
(probability of accomplishing the mitigating result if implemented as
planned), the likelihood of effective implementation (probability
implemented as planned), and;
(2) The practicability of the measures for applicant
implementation, which may consider such things as cost, impact on
operations, and, in the case of a military readiness activity,
personnel safety, practicality of implementation, and impact on the
effectiveness of the military readiness activity.
In addition to the measures described later in this section, the
Navy will employ the following mitigation measures:
For in-water heavy machinery work other than pile driving,
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;
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 those marine mammals for which Level B harassment take
has not been requested, in-water pile installation/removal will shut
down immediately if such species are observed within or entering the
Level B harassment zone; and
If take reaches the authorized limit for an authorized
species, pile installation/removal will shut down immediately if these
species approach the Level B harassment zone to avoid additional take.
The following mitigation measures apply to the Navy's in-water
construction activities.
Establishment of Shutdown Zones--The Navy will establish
shutdown zones for all pile driving and removal activities. The purpose
of a shutdown zone is generally to define an area within which shutdown
of the activity would occur upon sighting of a marine mammal (or in
anticipation of an animal entering the defined area). Shutdown zones
will vary based on the activity type and marine mammal hearing group
(Table 10). In addition to the shutdown zones listed in Table 10, the
Navy has proposed to shut down pile driving if a cetacean is observed
within the Level B harassment zone.
PSOs--The placement of PSOs during all pile driving and
removal activities (described in detail in the Proposed Monitoring and
Reporting section) will ensure that the entire shutdown zone is visible
during pile driving and removal (except where structures may interfere
with visibility of harbor seals). Should environmental conditions
deteriorate such that marine mammals within the entire shutdown zone
would not be visible (e.g., fog, heavy rain), pile driving and removal
must be delayed until the PSO is confident marine mammals within the
shutdown zone could be detected.
Table 10--Shutdown Zones During Pile Installation and Removal
----------------------------------------------------------------------------------------------------------------
Cetaceans (m) Phocids (m) Otariids (m)
----------------------------------------------------------------------------------------------------------------
All Vibratory Pile Driving...................................... 65 30 10
All Impact Pile Driving......................................... 355 160 15
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Monitoring for Level A and Level B Harassment--The Navy
will monitor the Level B harassment zones (areas where SPLs are equal
to or exceed the 160 dB rms threshold for impact driving and the 120 dB
rms threshold during vibratory pile driving) to the extent practicable
and the Level A harassment zones. Monitoring zones provide utility
[[Page 48222]]
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 cessation of
activity should the animal enter the shutdown zone. Placement of PSOs
on the pier, shoreline, and a vessel (see Proposed Monitoring and
Reporting) around the TPP site will allow PSOs to observe marine
mammals within the Level B harassment zones.
Pre-activity Monitoring--Prior to the start of daily in-
water construction activity, or whenever a break in pile driving/
removal 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 considered cleared when a marine mammal has not been observed within
the zone for that 30-minute period. If a marine mammal is observed
within the shutdown zone, a soft-start cannot proceed until the animal
has left the zone or has not been observed for 15 minutes. When a
marine mammal for which Level B harassment take is authorized is
present in the Level B harassment zone, activities may begin and Level
B harassment take will be recorded. If the entire Level B harassment
zone is not visible at the start of construction, pile driving
activities can begin. If work ceases for more than 30 minutes, the pre-
activity monitoring of the shutdown zones will commence.
Soft Start--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 will
be required to provide an initial set of three strikes from the hammer
at reduced energy, followed by a 30-second waiting period. This
procedure will be conducted three times before impact pile driving
begins. Soft start will be implemented at the start of each day's
impact pile driving and at any time following cessation of impact pile
driving for a period of 30 minutes or longer.
Pile driving energy attenuator--The Navy will use a marine
pile-driving energy attenuator (i.e., air bubble curtain system) during
impact pile driving. The use of sound attenuation will reduce SPLs and
the size of the zones of influence for Level A harassment and Level B
harassment. Bubble curtains will meet the following requirements:
[cir] The bubble curtain must distribute air bubbles around 100
percent of the piling perimeter for the full depth of the water column.
[cir] The lowest bubble ring shall be in contact with the mudline
for the full circumference of the ring, and the weights attached to the
bottom ring shall ensure 100 percent mudline contact. No parts of the
ring or other objects shall prevent full mudline contact.
[cir] The bubble curtain shall be operated such that there is
proper (equal) balancing of air flow to all bubblers.
Based on our evaluation of the Navy'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 ensuring that the most value is obtained from the
required monitoring.
Monitoring and reporting requirements prescribed by NMFS should
contribute to improved understanding of one or more of the following:
Occurrence of marine mammal species or stocks in the area
in which take is anticipated (e.g., presence, abundance, distribution,
density).
Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) Action or environment
(e.g., source characterization, propagation, ambient noise); (2)
affected species (e.g., life history, dive patterns); (3) co-occurrence
of marine mammal species with the action; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas).
Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors.
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks.
Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important physical components of
marine mammal habitat).
Mitigation and monitoring effectiveness.
Visual Monitoring
Marine mammal monitoring must be conducted in accordance with the
Marine Mammal Monitoring Plan. Marine mammal monitoring during pile
driving and removal must be conducted by NMFS-approved PSOs in a manner
consistent with the following:
Independent PSOs (i.e., not construction personnel) who
have no other assigned tasks during monitoring periods must be used;
Where a team of three or more PSOs are required, a lead
observer or monitoring coordinator must be designated. The lead
observer must have prior experience working as a marine mammal observer
during construction;
Other PSOs may substitute education (degree in biological
science or related field) or training for experience; and
The Navy must submit PSO curriculum vitae for approval by
NMFS prior to the onset of pile driving.
PSOs must have the following additional qualifications:
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, times, and reason for implementation
of mitigation (or why mitigation was not implemented when required);
and marine mammal behavior.
Ability to communicate orally, by radio or in person, with
project
[[Page 48223]]
personnel to provide real-time information on marine mammals observed
in the area as necessary.
At least two PSOs will monitor for marine mammals during all pile
driving and removal activities. PSO locations will provide a view of
the entire shutdown zone for all activities, other than areas where
structures may potentially block limited portions of the zone, and as
much of the Level B harassment zones as possible. PSO locations are as
follows:
i. During vibratory pile driving, two PSOs will be stationed on the
pier or shore.
ii. During impact pile driving, two PSOs will be stationed on the
pier, and one additional PSO will observe from a vessel positioned
approximately 200 m from shore.
Monitoring will be conducted 30 minutes before, during, and 30
minutes after pile driving/removal activities. In addition, observers
shall record all incidents of marine mammal occurrence, regardless of
distance from activity, and shall document any behavioral reactions in
concert with distance from piles being driven or removed. Pile driving
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.
Reporting
A draft marine mammal monitoring report will be submitted to NMFS
within 90 days after the completion of pile driving and removal
activities. The report will include an overall description of work
completed, a narrative regarding marine mammal sightings, and
associated PSO data sheets. Specifically, the report must include:
Dates and times (begin and end) of all marine mammal
monitoring.
Construction activities occurring during each daily
observation period, including how many and what type of piles were
driven or removed and by what method (i.e., impact or vibratory).
Weather parameters and water conditions during each
monitoring period (e.g., wind speed, percent cover, visibility, sea
state).
The number of marine mammals observed, by species,
relative to the pile location and if pile driving or removal was
occurring at time of sighting.
Age and sex class, if possible, of all marine mammals
observed.
PSO locations during marine mammal monitoring.
Distances and bearings of each marine mammal observed to
the pile being driven or removed for each sighting (if pile driving or
removal was occurring at time of sighting).
Description of any marine mammal behavior patterns during
observation, including direction of travel and estimated time spent
within the Level A and Level B harassment zones while the source was
active.
Number of individuals of each species (differentiated by
month as appropriate) detected within the monitoring zone, and
estimates of number of marine mammals taken, by species (a correction
factor may be applied to total take numbers, as appropriate).
Detailed information about any implementation of any
mitigation triggered (e.g., shutdowns and delays), a description of
specific actions that ensued, and resulting behavior of the animal, if
any.
Description of attempts to distinguish between the number
of individual animals taken and the number of incidences of take, such
as ability to track groups or individuals.
If no comments are received from NMFS within 30 days, the draft
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 event that personnel involved in the construction activities
discover an injured or dead marine mammal, the IHA-holder shall report
the incident to the Office of Protected Resources (OPR) (301-427-8401),
NMFS and to the West Coast Region Stranding Hotline (866-767-6114) as
soon as feasible. If the death or injury was clearly caused by the
specified activity, the IHA-holder must immediately cease the specified
activities until NMFS is able to review the circumstances of the
incident and determine what, if any, additional measures are
appropriate to ensure compliance with the terms of the IHA. The IHA-
holder must not resume their activities until notified by NMFS.
The report must include the following information:
i. Time, date, and location (latitude/longitude) of the first
discovery (and updated location information if known and applicable);
ii. Species identification (if known) or description of the
animal(s) involved;
iii. Condition of the animal(s) (including carcass condition if the
animal is dead);
iv. Observed behaviors of the animal(s), if alive;
v. If available, photographs or video footage of the animal(s); and
vi. General circumstances under which the animal was discovered.
Negligible Impact Analysis and Determination
NMFS has defined negligible impact as an impact resulting from the
specified activity that cannot be reasonably expected to, and is not
reasonably likely to, adversely affect the species or stock through
effects on annual rates of recruitment or survival (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough
information on which to base an impact determination. In addition to
considering estimates of the number of marine mammals that might be
``taken'' through harassment, NMFS considers other factors, such as the
likely nature of any responses (e.g., intensity, duration), the context
of any responses (e.g., critical reproductive time or location,
migration), as well as effects on habitat, and the likely effectiveness
of the mitigation. We also assess the number, intensity, and context of
estimated takes by evaluating this information relative to population
status. Consistent with the 1989 preamble for NMFS's implementing
regulations (54 FR 40338; September 29, 1989), the impacts from other
past and ongoing anthropogenic activities are incorporated into this
analysis via their impacts on the environmental baseline (e.g., as
reflected in the regulatory status of the species, population size and
growth rate where known, ongoing sources of human-caused mortality, or
ambient noise levels).
To avoid repetition, this introductory discussion of our analyses
applies to all of the species listed in Table 9, given that many of the
anticipated effects of this project on different marine mammal stocks
are expected to be relatively similar in nature. Where there are
meaningful differences between species or stocks in anticipated
individual responses to activities, impact of expected take on the
population due to differences in population status, or impacts on
habitat, they are described independently in the analysis below. The
analysis below applies to both the Year 1 and Year 2 proposed IHAs,
except where noted otherwise.
Pile driving and removal activities associated with the project, as
outlined previously, have the potential to disturb or displace marine
mammals. Specifically, the specified activities may result in take, in
the form of Level A harassment and Level B harassment from underwater
sounds generated by pile driving and removal. Potential takes
[[Page 48224]]
could occur if marine mammals are present in zones ensonified above the
thresholds for Level A or Level B harassment, identified above, while
activities are underway.
The nature of the pile driving project precludes the likelihood of
serious injury or mortality. The mitigation is expected to ensure that
no Level A harassment occurs to any species except harbor seal, which
may be taken by Level A harassment during Year 1 activities. The nature
of the estimated takes anticipated to occur are similar among all
species and similar in Year 1 and Year 2, other than the potential
Level A harassment take of harbor seal in Year 1, described further
below.
For all species and stocks, take will occur within a limited
portion of Hood Canal, and for the Hood Canal stock of harbor seals,
the project site is approximately 13.2 km (8.2 mi) away from the
nearest major haulout at the mouth of the Dosewallips River. For all
species other than harbor seal, take would be limited to Level B
harassment only due to potential behavioral disturbance and TTS.
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). 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
associated with the proposed project may produce sound at distances of
many kilometers from the project site, the project site itself is
located on a busy waterfront with high amounts of vessel traffic.
Therefore, we expect that animals disturbed by project sound would
simply avoid the area and use more-preferred habitats, particularly as
pile driving is expected to occur for a maximum of five hours per day.
Further, the instances of take proposed for authorization for killer
whale West Coast Transient stock, harbor porpoise Washington Inland
Waters stock, Steller sea lion Eastern U.S. stock, and California sea
lion United States stock is small when compared to stock abundance.
In addition to the expected effects resulting from proposed Level B
harassment, we anticipate that harbor seals may sustain some Level A
harassment in the form of auditory injury in Year 1 only. However,
animals 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 frequency range of the energy
produced by pile driving (i.e., the low-frequency region below 2kHz),
not severe hearing impairment or impairment in the reigns of greatest
hearing sensitivity. If hearing impairment does occur, it is most
likely that the affected animal would lose a few dBs 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.
As noted above in the Description of Marine Mammals in the Area of
Specified Activities, the Navy has identified a few observations of
harbor seal births at Kitsap Bangor. However, Kitsap Bangor is not a
significant rookery area; observation of these births are very rare,
and only a few have been reported. The closest major haulouts to Kitsap
Bangor that are regularly used by harbor seals are at the mouth of the
Dosewallips River, located approximately 13.2 km (8.2 mi) away. Given
the rarity of harbor seal births at Kitsap Bangor and the maximum of
five hours of pile driving anticipated in a day, we do not expect
harbor seals to give birth in the TPP project area while the project is
underway.
The project is also not expected to have significant adverse
effects on affected marine mammals' habitats. The project activities
will 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 or serious injury is anticipated or
authorized.
For all species except harbor seal, no Level A harassment
is anticipated or proposed for authorization.
The Level A harassment exposures are anticipated to result
only in slight PTS, within the lower frequencies associated with pile
driving for harbor seals only;
The intensity of anticipated takes by Level B harassment
is relatively low for all stocks.
Pile driving is only expected to occur for a maximum of
five hours in a day.
We do not expect significant or long-term negative effects
to marine mammal habitat.
Year 1 IHA--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 Navy's construction activities will
have a negligible impact on all affected marine mammal species or
stocks.
Year 2 IHA--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 Navy's construction activities 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. When the predicted number of
individuals to be taken is fewer than one third of the species or stock
abundance, the take is considered to be of small numbers. Additionally,
other qualitative factors may be considered in the analysis, such as
the temporal or spatial scale of the activities.
For the Washington Inland Waters, Hood Canal stock of harbor seal,
no
[[Page 48225]]
valid abundance estimate is available. The most recent abundance
estimate for harbor seals in Washington inland waters is from 1999,
which estimated 1,088 harbor seals in the Washington Inland Waters,
Hood Canal stock. It is generally believed that harbor seal populations
have increased significantly since (e.g., Mapes, 2013). The estimated
instances of take of the Washington Inland Waters, Hood Canal stock of
harbor seals in Year 1 (Table 9) appear high when compared to the
latest stock abundance from 1999. However, when other qualitative
factors are used to inform an assessment of the likely number of
individual harbor seals taken, the resulting numbers are considered
small in Year 1 and Year 2.
We anticipate that estimated takes of harbor seals are likely to
occur only within some portion of the relevant population, rather than
to animals from the stock as a whole. For example, takes anticipated to
occur at Kitsap Bangor would be expected to accrue to the same
individual seals that routinely occur on haulouts at these locations,
rather than occurring to new seals on each construction day. In
summary, harbor seals taken as a result of the specified activities are
expected to comprise only a limited portion of individuals comprising
the overall relevant stock abundance. Therefore, we find that small
numbers of harbor seals will be taken relative to the population size
of the Hood Canal stock of harbor seal in Year 1 and Year 2.
For all other species and stocks, our analysis shows that, in Year
1 and Year 2, take of all species or stocks is below one third of the
estimated stock abundance. The number of animals authorized to be taken
for the killer whale West Coast Transient stock, harbor porpoise
Washington Inland Waters stock, Steller sea lion Eastern U.S. stock,
and California sea lion United States stock, would be considered small
relative to the relevant stock's abundances even if each estimated
taking occurred to a new individual, which is an unlikely scenario.
Year 1 IHA--Based on the analysis contained herein of the activity
(including the 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 in Year 1 of the project.
Year 2 IHA--Based on the analysis contained herein of the activity
(including the 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 in Year 2 of the project.
Unmitigable Adverse Impact Analysis and Determination
There are no relevant subsistence uses of the affected marine
mammal stocks or species implicated by this action. Therefore, NMFS has
determined that the total taking of affected species or 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 whenever we propose to authorize take for
endangered or threatened species.
No incidental take of ESA-listed species is proposed for
authorization or expected to result from this activity. Therefore, NMFS
has determined that formal consultation under section 7 of the ESA is
not required for this action.
Proposed Authorization
As a result of these preliminary determinations, NMFS proposes to
issue an IHA to Navy for conducting the Transit Protection Program Pier
and Support Facilities Project at Naval Base Kitsap Bangor in
Silverdale, Washington over two years, beginning July 2021 and July
2022, provided the previously mentioned mitigation, monitoring, and
reporting requirements are incorporated. Drafts of the proposed IHAs
can be found at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.
Request for Public Comments
We request comment on our analyses, the proposed authorizations,
and any other aspect of this notice of proposed IHAs for the proposed
Transit Protection Program Pier and Support Facilities Project. We also
request at this time comment on the potential Renewal of these proposed
IHAs as described in the paragraph below. Please include with your
comments any supporting data or literature citations to help inform
decisions on the request for these IHAs or subsequent Renewal IHAs.
On a case-by-case basis, NMFS may issue a one-time, one-year
Renewal IHA following notice to the public providing an additional 15
days for public comments when (1) up to another year of identical or
nearly identical activities, as described in the Description of
Proposed Activity section of this notice, is planned or (2) the
activities as described in the Description of Proposed Activity section
of this notice would not be completed by the time the IHA expires and a
Renewal would allow for completion of the activities beyond that
described in the Dates and Duration section of this notice, provided
all of the following conditions are met:
A request for renewal is received no later than 60 days
prior to the needed Renewal IHA effective date (recognizing that the
Renewal IHA expiration date cannot extend beyond one year from
expiration of the initial IHA).
The request for renewal must include the following:
(1) An explanation that the activities to be conducted under the
requested Renewal IHA are identical to the activities analyzed under
the initial IHA, are a subset of the activities, or include changes so
minor (e.g., reduction in pile size) that the changes do not affect the
previous analyses, mitigation and monitoring requirements, or take
estimates (with the exception of reducing the type or amount of take).
(2) A preliminary monitoring report showing the results of the
required monitoring to date and an explanation showing that the
monitoring results do not indicate impacts of a scale or nature not
previously analyzed or authorized.
Upon review of the request for Renewal, the status of the
affected species or stocks, and any other pertinent information, NMFS
determines that there are no more than minor changes in the activities,
the mitigation and monitoring measures will remain the same and
appropriate, and the findings in the initial IHA remain valid.
Dated: August 5, 2020.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2020-17409 Filed 8-7-20; 8:45 am]
BILLING CODE 3510-22-P