[Federal Register Volume 79, Number 143 (Friday, July 25, 2014)]
[Notices]
[Pages 43402-43424]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2014-17446]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XD341
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to a Marine Reconstruction Project
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; proposed incidental harassment authorization; request
for comments.
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SUMMARY: NMFS has received a request from the Port of Friday Harbor, WA
(Port) for authorization to take marine mammals incidental to
construction activities as part of a marina reconstruction project.
Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting
comments on its proposal to issue an incidental harassment
authorization (IHA) to the Port to incidentally take marine mammals, by
Level B Harassment only, during the specified activity.
DATES: Comments and information must be received no later than August
25, 2014.
ADDRESSES: Comments on the application should be addressed to Jolie
Harrison, Supervisor, Incidental Take Program, Permits and Conservation
Division, Office of Protected Resources, National Marine Fisheries
Service. Physical comments should be sent to 1315 East-West Highway,
Silver Spring, MD 20910 and electronic comments should be sent to
[email protected].
Instructions: NMFS is not responsible for comments sent by any
other method, to any other address or individual, or received after the
end of the comment period. Comments received electronically, including
all attachments, must not exceed a 25-megabyte file size. Attachments
to electronic comments will be accepted in Microsoft Word or Excel or
Adobe PDF file formats only. All comments received are a part of the
public record and will generally be posted to the Internet at
www.nmfs.noaa.gov/pr/permits/incidental.htm 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: Ben Laws, Office of Protected
Resources, NMFS, (301) 427-8401.
SUPPLEMENTARY INFORMATION:
Availability
An electronic copy of the Port's application and supporting
documents, as well as a list of the references cited in this document,
may be obtained by visiting the Internet at: www.nmfs.noaa.gov/pr/permits/incidental.htm. In case of problems accessing these documents,
please call the contact listed above (see FOR FURTHER INFORMATION
CONTACT).
National Environmental Policy Act (NEPA)
We are preparing an Environmental Assessment (EA) in accordance
with NEPA and the regulations published by the Council on Environmental
Quality and will consider comments submitted in response to this notice
as part of that process. The EA will be posted at the foregoing Web
site once it is finalized.
Background
Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.)
direct the Secretary of Commerce to allow, upon request by U.S.
citizens who engage in a specified activity (other than commercial
fishing) within a specified area, the incidental, but not intentional,
taking of small numbers of marine mammals, providing that certain
findings are made and the necessary prescriptions are established.
The incidental taking of small numbers of marine mammals may be
allowed only if NMFS (through authority delegated by the Secretary)
finds that the total taking by the specified activity during the
specified time period will (i) have a negligible impact on the species
or stock(s) and (ii) not have an unmitigable adverse impact on the
availability of the species or stock(s) for subsistence uses (where
relevant). Further, the permissible methods of taking and requirements
pertaining to the mitigation, monitoring and reporting of such taking
must be set forth.
The allowance of such incidental taking under section 101(a)(5)(A),
by harassment, serious injury, death, or a combination thereof,
requires that regulations be established. Subsequently, a Letter of
Authorization may be issued pursuant to the prescriptions established
in such regulations, providing that the level of taking will be
consistent with the findings made for the total taking allowable under
the specific regulations. Under section 101(a)(5)(D), NMFS may
authorize such incidental taking by harassment only, for periods of not
more than one year, pursuant to requirements and conditions contained
within an IHA. The establishment of these prescriptions requires notice
and opportunity for public comment.
NMFS has defined ``negligible impact'' in 50 CFR 216.103 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.'' 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].''
Summary of Request
On August 12, 2013, we received a request from the Port for
authorization to take marine mammals incidental to pile driving and
removal associated with the reconstruction of a marina at Friday
Harbor, WA. The Port submitted revised versions of the request on
February 28, 2014, June 4, 2014, and June 11, 2014, after which we
deemed the application adequate and complete. The Port proposes to
conduct in-water work that may incidentally harass marine mammals
(i.e., pile driving and removal) during a portion of the in-water work
window established to protect fish species. This IHA would be valid
from September 1, 2014, through February 15, 2015. Please note that any
general reference to pile driving in this document is intended to refer
to both pile driving and removal.
The use of vibratory pile driving is expected to produce underwater
sound at levels that have the potential to result in behavioral
harassment of marine mammals. Species with the expected potential to be
present during all or a portion of the in-water work window include the
Steller sea lion (Eumetopias jubatus monteriensis), California sea
[[Page 43403]]
lion (Zalophus californianus), harbor seal (Phoca vitulina richardii),
Dall's porpoise (Phocoenoides dalli dalli), and harbor porpoise
(Phocoena phocoena vomerina). These species may occur year-round in the
vicinity of Friday Harbor, with the exception of the Steller and
California sea lions, which are generally absent during summer. The
Steller sea lion is present from fall to late spring (approximately
October to May), while the California sea lion is generally absent only
from approximately mid-June to August.
Description of the Specified Activity
Overview
The Port has determined that reconstruction of the marina is
necessary due to the increasing age of the existing structures. Repair
and replacement work is necessary in order to maintain the existing
purpose of the marina, which provides access, permanent and
short[hyphen]term moorage and berthing opportunities, and marina
support facilities to commercial and recreational boaters. A vibratory
hammer would be used to extract existing timber piles. Broken and
damaged pilings unable to be removed with the vibratory hammer may need
to be removed with a clamshell bucket. All new piles would be driven
with a vibratory hammer, to the extent possible. If vibratory driving
is not effective for any given pile (i.e., due to substrate
conditions), piles may be installed via confined drilling. No impact
pile driving is proposed for this project. The Port does not plan to
operate multiple pile driving rigs concurrently.
Dates and Duration
The allowable season for in-water work, including pile driving, in
the vicinity of Friday Harbor is July 16 through February 15, a window
established by the Washington Department of Fish and Wildlife in
coordination with NMFS and the U.S. Fish and Wildlife Service to
protect salmonid fish. The proposed action would occur only during a
portion of that window, from September 1, 2014, through February 15,
2015. The Port expects to require three days for pile removal and a
maximum of 29 days for pile installation, for a total of 32 days during
this period. Pile driving and removal may occur on any day during the
specified period, only during daylight hours.
Specific Geographic Region
The Port of Friday Harbor Marina is located at Friday Harbor, WA,
on the eastern shore of San Juan Island (see Figure 1-1 of the Port's
application). Friday Harbor is approximately 111 km north of Seattle,
WA and 52 km southeast of Victoria, BC. The Town of Friday Harbor is
located directly adjacent to the marina. Please refer to the U.S.
Navy's Marine Resource Assessment for the Pacific Northwest, which
documents and describes the marine resources that occur in Navy
operating areas of the Pacific Northwest, including Puget Sound (DoN,
2006), for additional information regarding physical and oceanographic
characteristics of the region. The document is publicly available at
www.navfac.navy.mil/products_and_services/ev/products_and_services/marine_resources/marine_resource_assessments.html (accessed June 16,
2014).
Detailed Description of Activities
The Friday Harbor Marina is an existing public marina providing
water access to the adjacent Town of Friday Harbor. The marina includes
approximately 500 vessel slips, of which up to 150 are available to
visiting boaters. The marina, protected by a U.S. Army Corps of
Engineers (USACE)-maintained floating breakwater to the north, provides
both permanent and temporary vessel moorage for commercial and
recreational vessels, a U.S. Customs office, fuel dock, and other
amenities. The Washington State Department of Transportation (WSDOT)
maintains the Friday Harbor Ferry Terminal just east of the marina.
The marina was built in the 1960s-70s and, due to increasing age of
the existing structures, reconstruction work is necessary to maintain
the existing purpose of the marina. The project will entail repair and
replacement of portions of the existing floats, piles, and walkways.
Specifically, the Port plans to replace existing dilapidated finger and
main walkway floats, treated timber walers (i.e., structural beams
typically mounted to floating docks), and a steel footbridge, and to
repair certain existing treated timber piles and bracing and install
some new floats. In addition, the Port plans to remove 95 creosote
timber piles (diameters range from 12-20 inches) and replace these with
52 steel pipe piles (twenty at 16-in diameter and 32 at 24-in
diameter). Only the latter portion of the specified activity (removal
and installation of piles) carries the potential for incidental take of
marine mammals, and is considered further in this document.
The Port plans to remove existing treated timber piles using
vibratory extraction. This involves use of a vibratory hammer, which is
suspended from a crane by a cable, attached to a derrick, and
positioned on the top of a pile. The pile is then unseated from the
sediments by engaging the hammer, creating a vibration that loosens the
sediments binding the pile, and then slowly lifting up on the hammer
with the aid of the crane. Once unseated, the crane will continue to
raise the hammer and pull the pile from the sediment. Vibratory removal
is anticipated to require approximately 10 to 15 minutes per pile. In
the event that broken or damaged pilings occur and are not able to be
completely removed via the vibratory hammer, a clamshell bucket may be
used to direct pull the pile remnant. Removal via clamshell bucket is
not expected to result in the potential for incidental take of marine
mammals.
The Port plans to install new piles using a vibratory driver as
well, to the extent possible. Vibratory installation of piles using the
vibratory hammer operates in the same manner as vibratory extraction,
except that the weight of the hammer presses the piling into the
substrate as the vibration results in liquefaction of the sediment. In
the event that difficult substrate conditions are encountered, piles
would be installed through drilling techniques. Unlike naked drilling,
this would be confined drilling within a steel casing. The steel pipe
pile would be installed as far as possible using the vibratory driver.
If a pile reaches refusal prior to reaching the required embedment
depth, an augur would be placed within the steel pipe to augur material
from within and below the pile until the desired embedment depth is
reached. Because any drilling would take place within the steel casing,
this technique is not expected to result in the harassment of marine
mammals. Pile installation is expected to require approximately 20 to
60 minutes per pile, with two to four piles installed per day. Pile
driving is therefore expected to require between 13-26 days depending
on the actual production rate. No impact pile driving will occur as
part of this project.
Description of Marine Mammals in the Area of the Specified Activity
There are 11 marine mammal species known to occur in the San Juan
Islands region of Washington inland waters, including seven cetaceans
and four pinnipeds. The harbor seal is a year-round resident in
Washington waters, while the Steller sea lion and California sea lion
are seasonally present. Dall's porpoises and harbor porpoises may also
occur with year-round regularity in the San Juan Islands. Remaining
species that could occur in the project area
[[Page 43404]]
include the killer whale (Orcinus orca; both transient and resident
ecotypes), humpback whale (Megaptera novaeangliae), gray whale
(Eschrichtius robustus), and minke whale (Balaenoptera acutorostrata
scammoni); the northern elephant seal (Mirounga angustirostris), and
the Pacific white-sided dolphin (Lagenorhynchus obliquidens). While
these latter six species could occur in the project area, we do not
believe that such occurrence is sufficiently likely to present a
reasonable likelihood of take incidental to the specified activity. For
more detail, please see the ``Proposed Monitoring and Reporting'' and
``Estimated Take by Incidental Harassment'' sections, later in this
document.
We have reviewed the Port's detailed species descriptions,
including life history information, for accuracy and completeness and
refer the reader to Section 3 of the Port's application instead of
reprinting the information here. Please also refer to NMFS' Web site
(www.nmfs.noaa.gov/pr/species/mammals) for generalized species accounts
and to the Navy's Marine Resource Assessment for the Pacific Northwest,
which documents and describes the marine resources that occur in Navy
operating areas of the Pacific Northwest, including the San Juan
Islands (DoN, 2006). The document is publicly available at
www.navfac.navy.mil/products_and_services/ev/products_and_services/marine_resources/marine_resource_assessments.html (accessed June 16,
2014).
Table 1 lists the 12 marine mammal stocks that could occur in the
vicinity of Friday Harbor during the project timeframe and summarizes
key information regarding stock status and abundance. Taxonomically, we
follow Committee on Taxonomy (2014). Please see NMFS' Stock Assessment
Reports (SAR), available at www.nmfs.noaa.gov/pr/sars, for more
detailed accounts of these stocks' status and abundance. All stocks are
addressed in the Pacific SARs (e.g., Carretta et al., 2013a), with the
exception of the Steller sea lion and transient killer whale, which are
treated in the Alaska SARs (e.g., Allen and Angliss, 2013a).
In the species accounts provided here, we offer a brief
introduction to the species and relevant stock as well as available
information regarding population trends and threats, and describe any
information regarding local occurrence. We first briefly describe the
occurrence of those species not expected to be affected by the Port's
activity before providing additional information for those species for
which incidental take is expected.
Table 1--Marine Mammals Potentially Present in the Vicinity of Friday Harbor
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Stock abundance (CV, Relative occurrence in
Species Stock ESA/MMPA status; Nmin, most recent PBR 3 Annual M/ San Juan Islands;
strategic (Y/N) 1 abundance survey) 2 SI 4 season of occurrence
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Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
Family Eschrichtiidae
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Gray whale.......................... Eastern North Pacific.. -; N................. 19,126 (0.071; 18,017; 558 \13\ 127 Seasonal to rare; more
2007). likely winter to
spring.
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Family Balaenopteridae (rorquals)
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Humpback whale...................... California/Oregon/ E/D; Y............... 1,918 (0.03; 1,855; \11\ 22 >=5.5 Seasonal to rare with
Washington (CA/OR/WA) 2011). highest likelihood
\6\. spring to fall.
Minke whale......................... CA/OR/WA............... -; N................. 478 (1.36; 202; 2008). 2 0 Seasonal; more likely
spring to fall.
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Order Cetartiodactyla--Cetacea--Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
Family Delphinidae
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Pacific white-sided dolphin......... CA/OR/WA............... -; N................. 26,930 (0.28; 21,406; 171 17.8 Rare but more likely
2008). summer and fall.
Killer whale \5\.................... West coast transient 6 -; N................. 243 (n/a; 2006)....... 2.4 0 Likely to rare.
7. E/D; Y............... 85 (n/a; 2012)........ 0.14 0 Likely to rare.
Eastern North Pacific
southern resident \6\.
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Family Phocoenidae (porpoises)
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Harbor porpoise..................... Washington inland -; N................. 10,682 (0.38; 7,841; 63 >=2.2 Likely to rare.
waters \8\. 2003).
Dall's porpoise..................... CA/OR/WA............... -; N................. 42,000 (0.33; 32,106; 257 >=0.4 Likely to rare.
2008).
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Order Carnivora--Superfamily Pinnipedia
Family Otariidae (eared seals and sea lions)
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California sea lion................. U.S.................... -; N................. 296,750 (n/a; 153,337; 9,200 >=431 Seasonal/common; not
2008). generally present in
Jul.
Steller sea lion.................... Eastern U.S. \6\....... -; N \9\............. \10\ 63,160-78,198 (n/ \12\ 65.1 Seasonal; not
a; 57,966; 2008-11). 1,552 generally present Jun-
Sep.
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[[Page 43405]]
Family Phocidae (earless seals)
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Harbor seal......................... Washington inland -; N................. 14,612 (0.15; 12,844; 771 13.4 Common; Year-round
waters \8\. 1999). resident.
Northern elephant seal.............. California breeding.... -; N................. 124,000 (n/a; 74,913; 4,382 >=10.4 Likely to rare.
2005).
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\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
exceeds PBR (see footnote 3) or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species
or stock listed under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ CV is coefficient of variation; Nmin is the minimum estimate of stock abundance. In some cases, CV is not applicable. For killer whales, the
abundance values represent direct counts of individually identifiable animals; therefore there is only a single abundance estimate with no associated
CV. For certain stocks of pinnipeds, abundance estimates are based upon observations of animals (often pups) ashore multiplied by some correction
factor derived from knowledge of the species' (or similar species') life history to arrive at a best abundance estimate; therefore, there is no
associated CV. In these cases, the minimum abundance may represent actual counts of all animals ashore.
\3\ Potential biological removal, 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 size (OSP).
\4\ These values, found in NMFS' SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial
fisheries, subsistence hunting, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value. All
values presented here are from the draft 2013 SARs (www.nmfs.noaa.gov/pr/sars/draft.htm).
\5\ Transient and resident killer whales are considered unnamed subspecies.
\6\ Abundance estimates (and resulting PBR values) for these stocks are new values presented in the draft 2013 SARs. This information was made available
for public comment and is currently under review and therefore may be revised prior to finalizing the 2013 SARs. However, we consider this information
to be the best available for use in this document.
\7\ The abundance estimate for this stock includes only animals from the ``inner coast'' population occurring in inside waters of southeastern Alaska,
British Columbia, and Washington--excluding animals from the ``outer coast'' subpopulation, including animals from California--and therefore should be
considered a minimum count. For comparison, the previous abundance estimate for this stock, including counts of animals from California that are now
considered outdated, was 354.
\8\ Abundance estimates for these stocks are greater than eight years old and are therefore not considered current. PBR is considered undetermined for
these stocks, as there is no current minimum abundance estimate for use in calculation. We nevertheless present the most recent abundance estimates
and PBR values, as these represent the best available information for use in this document.
\9\ The eastern distinct population segment of the Steller sea lion, previously listed under the ESA as threatened, was delisted on December 4, 2013 (78
FR 66140; November 4, 2013). Because this stock is not below its OSP size and the level of direct human-caused mortality does not exceed PBR, this
delisting action implies that the stock is no longer designated as depleted or as a strategic stock under the MMPA.
\10\ Best abundance is calculated as the product of pup counts and a factor based on the birth rate, sex and age structure, and growth rate of the
population. A range is presented because the extrapolation factor varies depending on the vital rate parameter resulting in the growth rate (i.e.,
high fecundity or low juvenile mortality).
\11\ This stock is known to spend a portion of time outside the U.S. EEZ. Therefore, only a portion of the PBR presented here is allocated for U.S.
waters. U.S. PBR allocation is half the total for humpback whales (11).
\12\ PBR is calculated for the U.S. portion of the stock only (excluding animals in British Columbia) and assumes that the stock is not within its OSP.
If we assume that the stock is within its OSP, PBR for the U.S. portion increases to 2,069.
\13\ Includes annual Russian harvest of 123 whales.
Humpback whales were common in Washington inland waters prior to
commercial whaling, but few sightings had been reported since that time
until approximately the past decade (Scheffer and Slipp, 1948;
www.orcanetwork.org). Opportunistic sightings have increased, and
humpback whales now appear to occur in small numbers in the Strait of
Juan de Fuca and San Juan Islands but also occasionally in Puget Sound
(Falcone et al., 2005), and are typically observed in spring and summer
(April-July). This species is still considered to have rare occurrence
in inland waters (more likely in warmer months), and is not expected to
be present in all areas or to remain in any given location for extended
periods of time.
Gray whales generally migrate southbound past Washington in late
December and January, and transit past Washington on the northbound
return in March to May. Gray whales do not generally make use of
Washington inland waters, but have been observed in certain portions of
those waters in all months of the year, with most records occurring
from March through June (Calambokidis et al., 2010;
www.orcanetwork.org) and associated with regular feeding areas. Usually
fewer than twenty gray whales visit the inner marine waters of
Washington and British Columbia beginning in about January, and six to
ten of these are individual whales that return most years to feeding
sites in northern Puget Sound. The remaining individuals occurring in
any given year generally appear unfamiliar with feeding areas, often
arrive emaciated, and commonly die of starvation (WDFW, 2012).
Minke whales of the California, Oregon, and Washington stock appear
to establish home ranges (e.g., Washington inland waters, central
California; Dorsey et al., 1990), as opposed to more migratory minke
whales in northern waters. Minke whales are reported in inland waters
year-round, although the majority of the records are from March through
November (Calambokidis and Baird, 1994), and are sighted primarily in
the San Juan Islands and Strait of Juan de Fuca (www.orcanetwork.org).
A majority of feeding observations in the San Juan Islands were over
submarine slopes of moderate incline at depths of 20-100 m (Hoelzel et
al., 1989).
Although a single species of killer whale is currently recognized,
three recognizable forms (or ecotypes) are known in the North Pacific
and killer whale taxonomy is unresolved. These three ecotypes,
distinguished on the basis of social and foraging behavior (among other
traits), include resident, transient, and offshore animals. Both
resident and transient whales may occur in Washington inland waters,
and
[[Page 43406]]
seasonal movements tend to be correlated with prey availability.
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, which feed on marine mammals, may occur in inland
waters in any month (www.orcanetwork.org), but several studies have
shown peaks in occurrences. Stacey et al. (1990) found bimodal peaks in
spring and fall for transients on the northeastern coast of British
Columbia, while Baird and Dill (1995) found some transient groups
frequenting the vicinity of harbor seal haul-out sites around southern
Vancouver Island during August and September. However, not all
transient groups were seasonal in these studies, and their movements
appear to be unpredictable. The number of west coast transients in
Washington inland waters at any one time is probably fewer than twenty
individuals (Wiles, 2004), although occurrence in inland waters has
increased in correlation with increasing abundance of some prey species
(e.g., seals, sea lions, and porpoises) (Houghton et al., in prep). In
the activity area, small groups of one to five individuals are sighted
intermittently throughout the year.
Southern resident killer whales, which eat fish, are most
frequently seen during the spring and summer months in the San Juan
Islands region, with intermittent sightings in Puget Sound. During fall
and early winter, this pattern reverses, with whales seen more
frequently in Puget Sound. During later winter months, residents spend
more time in outer waters of the coast. The Friday Harbor Whale Museum
keeps a database of verified marine mammal sightings (whale days) by
location quadrants. Between 1990 and 2008, in the September to February
window proposed for this project, an average of 3.2 killer whale
sightings were annually reported for the project area. From 2009-2012,
during the same timeframe, three reports of southern residents were
recorded for Friday Harbor.
Pacific white-sided dolphins are known to enter the inshore passes
of British Columbia and Washington, and have been encountered in the
Strait of Juan de Fuca and the Strait of Georgia (Stacey and Baird,
1991; Norman et al., 2004). Small groups have also been seen in Haro
Strait off San Juan Island. Pacific white-sided dolphins are considered
as occasional visitors to the inland waters region and occurrence is
considered rare.
Northern elephant seal breeding sites are located on beaches and
islands in California and Mexico. After their winter breeding season
and annual molt cycles, individuals typically disperse northward along
the Oregon and Washington coasts and may be present typically on only a
seasonal basis. However, a few individuals are now found in Washington
inland waters year-round. Haul-out areas for elephant seals are not as
predictable as for the other species of pinnipeds with more regular
occurrence. A few individuals use beaches at Protection Island (46 km
south of Friday Harbor) and Smith/Minor Islands (27 km south) (Jeffries
et al., 2000). Typically these sites host only small numbers of
animals.
Steller Sea Lion
Steller sea lions are distributed mainly around the coasts to the
outer continental shelf along the North Pacific rim from northern
Hokkaido, Japan through the Kuril Islands and Okhotsk Sea, Aleutian
Islands and central Bering Sea, southern coast of Alaska and south to
California (Loughlin et al., 1984). Based on distribution, population
response, and phenotypic and genotypic data, two separate stocks of
Steller sea lions are recognized within U.S. waters, with the
population divided into western and eastern distinct population
segments (DPS) at 144[deg] W (Cape Suckling, Alaska) (Loughlin, 1997).
The eastern DPS extends from California to Alaska, including the Gulf
of Alaska, and is the only stock that may occur in the project area.
According to NMFS' recent status review (NMFS, 2013), the best
available information indicates that the overall abundance of eastern
DPS Steller sea lions has increased for a sustained period of at least
three decades while pup production has also increased significantly,
especially since the mid-1990s. Johnson and Gelatt (2012; in NMFS,
2013) provided an analysis of growth trends of the entire eastern DPS
from 1979-2010, indicating that the stock increased during this period
at an annual rate of 4.2 percent (90% CI 3.7-4.6). Most of the overall
increase occurred in the northern portion of the range (southeast
Alaska and British Columbia), but pup counts in Oregon and California
also increased significantly (e.g., Merrick et al., 1992; Sease et al.,
2001; Olesiuk and Trites, 2003; Fritz et al., 2008; Olesiuk, 2008;
NMFS, 2008, 2013). In Washington, Pitcher et al. (2007) reported that
Steller sea lions, presumably immature animals and non-breeding adults,
regularly used four haul-outs, including two ``major'' haul-outs (>50
animals). The same study reported that the numbers of sea lions counted
between 1989 and 2002 on Washington haul-outs increased significantly
(average annual rate of 9.2 percent) (Pitcher et al., 2007). Although
the stock size has increased, its status relative to OSP size is
unknown. However, the consistent long-term estimated annual rate of
increase may indicate that the stock is reaching OSP size (Allen and
Angliss, 2013a).
Data from 2005-10 show a total mean annual mortality rate of 5.71
(CV = 0.23) sea lions per year from observed fisheries and 11.25
reported takes per year that could not be assigned to specific
fisheries, for an approximate total from all fisheries of 17 eastern
Steller sea lions (Allen and Angliss, 2013a). In addition,
opportunistic observations and stranding data indicate that an
additional 32 animals are killed or seriously injured each year through
interaction with commercial and recreational troll fisheries and by
entanglement (Allen and Angliss, 2013b). The annual average take for
subsistence harvest in Alaska was 11.9 individuals in 2004-08 (Allen
and Angliss, 2013a). Data on community subsistence harvests is no
longer being collected, and this average is retained as an estimate for
current and future subsistence harvest. Sea lion deaths are also known
to occur because of illegal shooting, vessel strikes, or capture in
research gear and other traps, totaling 4.2 animals per year from 2007-
11 (Allen and Angliss, 2013b). The total annual human-caused mortality
is a minimum estimate because takes via fisheries interactions and
subsistence harvest in Canada are poorly known, although are believed
to be small.
The eastern stock breeds in rookeries located in southeast Alaska,
British Columbia, Oregon, and California. There are no known breeding
rookeries in Washington (Allen and Angliss, 2013a) but eastern stock
Steller sea lions are present year-round along the outer coast of
Washington, including immature animals or non-breeding adults of both
sexes. In 2011, the minimum count for Steller sea lions in Washington
was 1,749 (Allen and Angliss, 2013b), up from 516 in 2001 (Pitcher et
al., 2007). In Washington, Steller sea lions primarily occur at haul-
out sites along the outer coast from the Columbia River to Cape
Flattery and in inland waters sites along the Vancouver Island
coastline of the Strait of Juan de Fuca (Jeffries et al., 2000; Olesiuk
and Trites, 2003; Olesiuk, 2008). Numbers vary seasonally in Washington
waters with peak numbers present during the fall and winter months
(Jeffries et al., 2000). Haul-outs in the San Juan Islands
[[Page 43407]]
include Green Point on Speiden Island (13 km northwest of Friday
Harbor), North Peapod Rock (23 km northeast of Friday Harbor), Bird
Rocks (19 km southeast of Friday Harbor), and Whale Rock (11 km south
of Friday Harbor) (Jeffries et al., 2000).
Harbor Seal
Harbor seals inhabit coastal and estuarine waters and shoreline
areas of the northern hemisphere from temperate to polar regions. The
eastern North Pacific subspecies is found from Baja California north to
the Aleutian Islands and into the Bering Sea. Multiple lines of
evidence support the existence of geographic structure among harbor
seal populations from California to Alaska (e.g., O'Corry-Crowe et al.,
2003; Temte, 1986; Calambokidis et al., 1985; Kelly, 1981; Brown, 1988;
Lamont, 1996; Burg, 1996). Harbor seals are generally non-migratory,
and analysis of genetic information suggests that genetic differences
increase with geographic distance (Westlake and O'Corry-Crowe, 2002).
However, because stock boundaries are difficult to meaningfully draw
from a biological perspective, three separate harbor seal stocks are
recognized for management purposes along the west coast of the
continental U.S.: (1) Inland waters of Washington (including Hood
Canal, Puget Sound, and the Strait of Juan de Fuca out to Cape
Flattery), (2) outer coast of Oregon and Washington, and (3) California
(Carretta et al., 2013a). Multiple stocks are recognized in Alaska.
Samples from Washington, Oregon, and California demonstrate a high
level of genetic diversity and indicate that the harbor seals of
Washington inland waters possess unique haplotypes not found in seals
from the coasts of Washington, Oregon, and California (Lamont et al.,
1996). Only the Washington inland waters stock may be found in the
project area.
Recent genetic evidence suggests that harbor seals of Washington
inland waters may have sufficient population structure to warrant
division into multiple distinct stocks (Huber et al., 2010, 2012).
Based on studies of pupping phenology, mitochondrial DNA, and
microsatellite variation, Carretta et al. (2013b) suggest division of
the Washington inland waters stock into three new populations, and
present these as prospective stocks: (1) Southern Puget Sound (south of
the Tacoma Narrows Bridge); (2) Washington northern inland waters
(including Puget Sound north of the Tacoma Narrows Bridge, the San Juan
Islands, and the Strait of Juan de Fuca); and (3) Hood Canal. Until
this stock structure is accepted, we consider a single Washington
inland waters stock.
The best available abundance estimate was derived from aerial
surveys of harbor seals in Washington conducted during the pupping
season in 1999, during which time the total numbers of hauled-out seals
(including pups) were counted (Jeffries et al., 2003). Radio-tagging
studies conducted at six locations collected information on harbor seal
haul-out patterns in 1991-92, resulting in a pooled correction factor
(across three coastal and three inland sites) of 1.53 to account for
animals in the water which are missed during the aerial surveys (Huber
et al., 2001), which, coupled with the aerial survey counts, provides
the abundance estimate (see Table 1).
Harbor seal counts in Washington State increased at an annual rate
of six percent from 1983-96, increasing to ten percent for the period
1991-96 (Jeffries et al., 1997). The population is thought to be
stable, and the Washington inland waters stock is considered to be
within its OSP size (Jeffries et al., 2003).
Data from 2007-11 indicate that a minimum of four harbor seals are
killed annually in Washington inland waters commercial fisheries, while
mean annual mortality for recreational fisheries is one seal (Carretta
et al., 2013b). Animals captured east of Cape Flattery are assumed to
belong to this stock. The estimate is considered a minimum because
there are likely additional animals killed in unobserved fisheries and
because not all animals stranding as a result of fisheries interactions
are likely to be recorded. Another 8.4 harbor seals per year are
estimated to be killed as a result of various non-fisheries human
interactions (Carretta et al., 2013b). Tribal subsistence takes of this
stock may occur, but no data on recent takes are available.
The nearest known haul-out sites to Friday Harbor are the
intertidal rocks northeast of Point George on Shaw Island
(approximately 4-5 km northeast of Friday Harbor; see Figure 1-3 of the
Port's application). The level of use during the project timeframe is
unknown, but would be expected to be less as air temperatures become
colder than water temperatures in the fall and winter.
California Sea Lion
California sea lions range from the Gulf of California north to the
Gulf of Alaska, with breeding areas located in the Gulf of California,
western Baja California, and southern California. Five genetically
distinct geographic populations have been identified: (1) Pacific
temperate, (2) Pacific subtropical, and (3-5) southern, central, and
northern Gulf of California (Schramm et al., 2009). Rookeries for the
Pacific temperate population are found within U.S. waters and just
south of the U.S.-Mexico border, and animals belonging to this
population may be found from the Gulf of Alaska to Mexican waters off
Baja California. For management purposes, a stock of California sea
lions comprising those animals at rookeries within the U.S. is defined
(i.e., the U.S. stock of California sea lions) (Carretta et al.,
2013a). Pup production at the Coronado Islands rookery in Mexican
waters is considered an insignificant contribution to the overall size
of the Pacific temperate population (Lowry and Maravilla-Chavez, 2005).
Trends in pup counts from 1975 through 2008 have been assessed for
four rookeries in southern California and for haul-outs in central and
northern California. During this time period counts of pups increased
at an annual rate of 5.4 percent, excluding six El Nino years when pup
production declined dramatically before quickly rebounding (Carretta et
al., 2013a). The maximum population growth rate was 9.2 percent when
pup counts from the El Ni[ntilde]o years were removed. There are
indications that the California sea lion may have reached or is
approaching carrying capacity, although more data are needed to confirm
that leveling in growth persists (Carretta et al., 2013a).
Data from 2003-09 indicate that a minimum of 337 (CV = 0.56)
California sea lions are killed annually in commercial fisheries. In
addition, a summary of stranding database records for 2005-09 shows an
annual average of 65 such events, which is likely a gross underestimate
because most carcasses are not recovered. California sea lions may also
be removed because of predation on endangered salmonids (seventeen per
year, 2008-10) or incidentally captured during scientific research
(three per year, 2005-09) (Carretta et al., 2013a). Sea lion mortality
has also been linked to the algal-produced neurotoxin domoic acid
(Scholin et al., 2000). Future mortality may be expected to occur, due
to the sporadic occurrence of such harmful algal blooms. There is
currently an Unusual Mortality Event (UME) declaration in effect for
California sea lions. Beginning in January 2013, elevated strandings of
California sea lion pups have been observed in southern California,
with live sea lion strandings nearly three times higher than the
historical average. Findings to date indicate that a likely contributor
to
[[Page 43408]]
the large number of stranded, malnourished pups was a change in the
availability of sea lion prey for nursing mothers, especially sardines.
The causes and mechanisms of this UME remain under investigation
(www.nmfs.noaa.gov/pr/health/mmume/californiasealions2013.htm; accessed
May 8, 2014).
An estimated 3,000 to 5,000 California sea lions migrate northward
along the coast to central and northern California, Oregon, Washington,
and Vancouver Island during the non-breeding season from September to
May (Jeffries et al., 2000) and return south the following spring
(Mate, 1975; Bonnell et al., 1983). Peak numbers of up to 1,000
California sea lions occur in Puget Sound during this time period
(Jeffries et al., 2000). The nearest documented California sea lion
haul-out sites to Friday Harbor are intertidal rocks and reef areas
around Trial Island and Race Rocks near Victoria, B.C. (approximately
24 km west of Friday Harbor). Small numbers of sea lions may
occasionally haul-out on navigation buoys in the San Juan Islands
(Jeffries et al., 2000).
Harbor Porpoise
Harbor porpoises are found primarily in inshore and relatively
shallow coastal waters (< 100 m) from Point Barrow (Alaska) to Point
Conception (California). Various genetic analyses and investigation of
pollutant loads indicate a low mixing rate for harbor porpoises along
the west coast of North America and likely fine-scale geographic
structure along an almost continuous distribution from California to
Alaska (e.g., Calambokidis and Barlow, 1991; Osmek et al., 1994;
Chivers et al., 2002, 2007). However, stock boundaries are difficult to
draw because any rigid line is generally arbitrary from a biological
perspective. On the basis of genetic data and density discontinuities
identified from aerial surveys, eight stocks have been identified in
the eastern North Pacific, including northern Oregon/Washington coastal
and inland Washington stocks (Carretta et al., 2013a). The Washington
inland waters stock includes individuals found east of Cape Flattery
and is the only stock that may occur in the project area.
Although long-term harbor porpoise sightings in southern Puget
Sound declined from the 1940s through the 1990s, sightings and
strandings have increased in Puget Sound in recent years and harbor
porpoise are now considered to regularly occur year-round in these
waters (Carretta et al., 2013a). Reasons for the apparent decline, as
well as the apparent rebound, are unknown. Recent observations may
represent a return to historical conditions, when harbor porpoises were
considered one of the most common cetaceans in Puget Sound (Scheffer
and Slipp, 1948). The status of harbor porpoises in Washington inland
waters relative to OSP is not known (Carretta et al., 2013a).
Data from 2005-09 indicate that a minimum of 2.2 Washington inland
waters harbor porpoises are killed annually in U.S. commercial
fisheries (Carretta et al., 2013a). Animals captured in waters east of
Cape Flattery are assumed to belong to this stock. This estimate is
considered a minimum because the Washington Puget Sound Region salmon
set/drift gillnet fishery has not been observed since 1994, and because
of a lack of knowledge about the extent to which harbor porpoise from
U.S. waters frequent the waters of British Columbia and are, therefore,
subject to fishery-related mortality. However, harbor porpoise takes in
the salmon drift gillnet fishery are unlikely to have increased since
the fishery was last observed, when few interactions were recorded, due
to reductions in the number of participating vessels and available
fishing time. Fishing effort and catch have declined throughout all
salmon fisheries in the region due to management efforts to recover
ESA-listed salmonids (Carretta et al., 2013a). In addition, an
estimated 0.4 animals per year are killed by non-fishery human causes
(e.g., ship strike, entanglement). In 2006, a UME was declared for
harbor porpoises throughout Oregon and Washington, and a total of 114
strandings were reported in 2006-07. The cause of the UME has not been
determined and several factors, including contaminants, genetics, and
environmental conditions, are still being investigated (Carretta et
al., 2013a).
Harbor porpoises occur year-round and breed in the waters around
the San Juan Archipelago and north into Canadian waters (Calambokidis
and Baird, 1994). Little information exists on harbor porpoise
occurrence in the project area, although it is suspected that in some
areas harbor porpoises migrate seasonally.
Dall's Porpoise
Dall's porpoises are endemic to temperate waters of the North
Pacific, typically in deeper waters between 30-62[deg] N, and are found
from northern Baja California to the northern Bering Sea. Stock
structure for Dall's porpoises is not well known; because there are no
cooperative management agreements with Mexico or Canada for fisheries
which may take this species, Dall's porpoises are divided for
management purposes into two discrete, noncontiguous areas: (1) Waters
off California, Oregon, and Washington, and (2) Alaskan waters
(Carretta et al., 2013a). Only individuals from the CA/OR/WA stock may
occur within the project area.
Data from 2002-08, from all fisheries for which mortality data are
available, indicate that a minimum of 0.4 animals are killed per year
(Carretta et al., 2013a). Species-specific information is not available
for Mexican fisheries, which could be an additional source of mortality
for animals beyond the stock boundaries delineated for management
purposes. No other sources of human-caused mortality are known.
Dall's porpoise distribution on the U.S. west coast is highly
variable between years and appears to be affected by oceanographic
conditions (Forney and Barlow, 1998); animals may spend more or less
time outside of U.S. waters as oceanographic conditions change. Because
distribution and abundance of this stock is so variable, population
trends are not available (Carretta et al., 2013a). In Washington,
Dall's porpoises are most abundant in offshore waters where they are
year-round residents, although interannual distribution is highly
variable (Green et al., 1992). In inland waters, Dall's porpoises are
most frequently observed in the Strait of Juan de Fuca and Haro Strait
between San Juan Island and Vancouver Island (Nysewander et al., 2005).
Potential Effects of the Specified Activity on Marine Mammals
This section includes a summary and discussion of the ways that
components of the specified activity may impact marine mammals. This
discussion also includes reactions that we consider to rise to the
level of a take and those that we do not consider to rise to the level
of a take (for example, with acoustics, we may include a discussion of
studies that showed animals not reacting at all to sound or exhibiting
barely measurable avoidance). This section is intended as a background
of potential effects and does not consider either the specific manner
in which this activity will be carried out or the mitigation that will
be implemented, and how either of those will shape the anticipated
impacts from this specific activity. The ``Estimated Take by Incidental
Harassment'' section later in this document will include a quantitative
analysis of the number of individuals that are expected to be taken by
this activity. The ``Negligible Impact
[[Page 43409]]
Analysis'' section will include the analysis of how this specific
activity will impact marine mammals and will consider the content of
this section, the ``Estimated Take by Incidental Harassment'' section,
the ``Proposed Mitigation'' section, and the ``Anticipated Effects on
Marine Mammal Habitat'' section to draw conclusions regarding the
likely impacts of this activity on the reproductive success or
survivorship of individuals and from that on the affected marine mammal
populations or stocks. In the following discussion, we provide general
background information on sound and marine mammal hearing before
considering potential effects to marine mammals from sound produced by
vibratory pile driving.
Description of Sound Sources
Sound travels in waves, the basic components of which are
frequency, wavelength, velocity, and amplitude. Frequency is the number
of pressure waves that pass by a reference point per unit of time and
is measured in hertz (Hz) or cycles per second. Wavelength is the
distance between two peaks of a sound wave; lower frequency sounds have
longer wavelengths than higher frequency sounds and attenuate
(decrease) more rapidly in shallower water. Amplitude is the height of
the sound pressure wave or the `loudness' of a sound and is typically
measured using the decibel (dB) scale. A dB is the ratio between a
measured pressure (with sound) and a reference pressure (sound at a
constant pressure, established by scientific standards). It is a
logarithmic unit that accounts for large variations in amplitude;
therefore, relatively small changes in dB ratings correspond to large
changes in sound pressure. When referring to sound pressure levels
(SPLs; the sound force per unit area), sound is referenced in the
context of underwater sound pressure to 1 microPascal ([mu]Pa). One
pascal is the pressure resulting from a force of one newton exerted
over an area of one square meter. The source level (SL) represents the
sound level at a distance of 1 m from the source (referenced to 1
[mu]Pa). The received level is the sound level at the listener's
position. Note that all underwater sound levels in this document are
referenced to a pressure of 1 [mu]Pa and all airborne sound levels in
this document are referenced to a pressure of 20 [mu]Pa.
Root mean square (rms) is the quadratic mean sound pressure over
the duration of an impulse. Rms is calculated by squaring all of the
sound amplitudes, averaging the squares, and then taking the square
root of the average (Urick, 1983). Rms accounts for both positive and
negative values; squaring the pressures makes all values positive so
that they may be accounted for in the summation of pressure levels
(Hastings and Popper, 2005). This measurement is often used in the
context of discussing behavioral effects, in part because behavioral
effects, which often result from auditory cues, may be better expressed
through averaged units than by peak pressures.
When underwater objects vibrate or activity occurs, sound-pressure
waves are created. These waves alternately compress and decompress the
water as the sound wave travels. Underwater sound waves radiate in all
directions away from the source (similar to ripples on the surface of a
pond), except in cases where the source is directional. The
compressions and decompressions associated with sound waves are
detected as changes in pressure by aquatic life and man-made sound
receptors such as hydrophones.
Even in the absence of sound from the specified activity, the
underwater environment is typically loud due to ambient sound. Ambient
sound is defined as environmental background sound levels lacking a
single source or point (Richardson et al., 1995), and the sound level
of a region is defined by the total acoustical energy being generated
by known and unknown sources. These sources may include physical (e.g.,
waves, earthquakes, ice, atmospheric sound), biological (e.g., sounds
produced by marine mammals, fish, and invertebrates), and anthropogenic
sound (e.g., vessels, dredging, aircraft, construction). A number of
sources contribute to ambient sound, including the following
(Richardson et al., 1995):
Wind and waves: The complex interactions between wind and
water surface, including processes such as breaking waves and wave-
induced bubble oscillations and cavitation, are a main source of
naturally occurring ambient noise for frequencies between 200 Hz and 50
kHz (Mitson, 1995). In general, ambient sound levels tend to increase
with increasing wind speed and wave height. Surf noise becomes
important near shore, with measurements collected at a distance of 8.5
km from shore showing an increase of 10 dB in the 100 to 700 Hz band
during heavy surf conditions.
Precipitation: Sound from rain and hail impacting the
water surface can become an important component of total noise at
frequencies above 500 Hz, and possibly down to 100 Hz during quiet
times.
Biological: Marine mammals can contribute significantly to
ambient noise levels, as can some fish and shrimp. The frequency band
for biological contributions is from approximately 12 Hz to over 100
kHz.
Anthropogenic: Sources of ambient noise related to human
activity include transportation (surface vessels and aircraft),
dredging and construction, oil and gas drilling and production, seismic
surveys, sonar, explosions, and ocean acoustic studies. Shipping noise
typically dominates the total ambient noise for frequencies between 20
and 300 Hz. In general, the frequencies of anthropogenic sounds are
below 1 kHz and, if higher frequency sound levels are created, they
attenuate rapidly (Richardson et al., 1995). Sound from identifiable
anthropogenic sources other than the activity of interest (e.g., a
passing vessel) is sometimes termed background sound, as opposed to
ambient sound.
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.
The only known available in-water background noise data in the San
Juan Islands area was collected on the west side of San Juan Island
(approximately 10 km west of Friday Harbor), as part of the Orcasound
in-water monitoring study. Data were collected between April 2004 and
November 2005, with average daytime in-water noise levels during the
summer (July-Aug) and non-summer (Oct-Apr) measured at 118 and 116 dB
rms, respectively (Veirs and Veirs, 2005). Known sound levels and
frequency ranges associated with anthropogenic sources similar to those
that would be used for this project are summarized in Table 2. Details
of the source types are described in the following text.
[[Page 43410]]
Table 2--Representative Sound Levels of Anthropogenic Sources
----------------------------------------------------------------------------------------------------------------
Frequency
Sound source range (Hz) Underwater sound level Reference
----------------------------------------------------------------------------------------------------------------
Small vessels........................... 250-1,000 151 dB rms at 1 m......... Richardson et al., 1995.
Tug docking gravel barge................ 200-1,000 149 dB rms at 100 m....... Blackwell and Greene,
2002.
Vibratory driving of 72-in steel pipe 10-1,500 180 dB rms at 10 m........ Reyff, 2007.
pile.
Impact driving of 36-in steel pipe pile. 10-1,500 195 dB rms at 10 m........ Laughlin, 2007.
Impact driving of 66-in cast-in-steel- 10-1,500 195 dB rms at 10 m........ Reviewed in Hastings and
shell (CISS) pile. Popper, 2005.
----------------------------------------------------------------------------------------------------------------
In-water construction activities associated with the project would
include vibratory pile driving and removal. The sounds produced by
these activities fall into the latter of two general sound types:
Impulse and continuous (defined in the following). 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). Please see
Southall et al., (2007) for an in-depth discussion of these concepts.
Pulsed sound sources (e.g., explosions, gunshots, sonic booms,
impact pile driving) produce signals that are brief (typically
considered to be less than one second), broadband, atonal transients
(ANSI, 1986; Harris, 1998; NIOSH, 1998; ISO, 2003; ANSI, 2005) and
occur either as isolated events or repeated in some succession. Pulsed
sounds are all characterized by a relatively rapid rise from ambient
pressure to a maximal pressure value followed by a rapid decay period
that may include a period of diminishing, oscillating maximal and
minimal pressures, and generally have an increased capacity to induce
physical injury as compared with sounds that lack these features.
Non-pulsed sounds can be tonal, narrowband, or broadband, brief or
prolonged, and may be either continuous or non-continuous (ANSI, 1995;
NIOSH, 1998). Some of these non-pulsed sounds can be transient signals
of short duration but without the essential properties of pulses (e.g.,
rapid rise time). Examples of non-pulsed sounds include those produced
by vessels, aircraft, machinery operations such as drilling or
dredging, vibratory pile driving, and active sonar systems (such as
those used by the U.S. Navy). The duration of such sounds, as received
at a distance, can be greatly extended in a highly reverberant
environment.
Vibratory hammers install piles by vibrating them and allowing the
weight of the hammer to push them into the sediment. Vibratory hammers
produce significantly less sound than impact hammers. Peak SPLs may be
180 dB or greater, but are generally 10 to 20 dB lower than SPLs
generated during impact pile driving of the same-sized pile (Oestman et
al., 2009). Rise time is slower, reducing the probability and severity
of injury, and sound energy is distributed over a greater amount of
time (Nedwell and Edwards, 2002; Carlson et al., 2005).
Marine Mammal Hearing
Hearing is the most important sensory modality for marine mammals.
To appropriately assess potential effects, 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 measured or estimated hearing ranges on the
basis of available behavioral data, audiograms derived using auditory
evoked potential techniques, anatomical modeling, and other data. The
lower and/or upper frequencies for some of these functional hearing
groups have been modified from those designated by Southall et al.
(2007). The functional groups and the associated frequencies are
indicated below (note that these frequency ranges do not necessarily
correspond to the range of best hearing, which varies by species):
Low-frequency cetaceans (mysticetes): Functional hearing
is estimated to occur between approximately 7 Hz and 30 kHz (extended
from 22 kHz; Watkins, 1986; Au et al., 2006; Lucifredi and Stein, 2007;
Ketten and Mountain, 2009; Tubelli et al., 2012);
Mid-frequency cetaceans (larger toothed whales, beaked
whales, and most delphinids): Functional hearing is estimated to occur
between approximately 150 Hz and 160 kHz;
High-frequency cetaceans (porpoises, river dolphins, and
members of the genera Kogia and Cephalorhynchus; now considered to
include two members of the genus Lagenorhynchus on the basis of recent
echolocation data and genetic data [May-Collado and Agnarsson, 2006;
Kyhn et al. 2009, 2010; Tougaard et al. 2010]): Functional hearing is
estimated to occur between approximately 200 Hz and 180 kHz; and
Pinnipeds in water: functional hearing is estimated to
occur between approximately 75 Hz to 100 kHz for Phocidae (true seals)
and between 100 Hz and 40 kHz for Otariidae (eared seals), with the
greatest sensitivity between approximately 700 Hz and 20 kHz. The
pinniped functional hearing group was modified from Southall et al.
(2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth et al.,
2013).
There are five marine mammal species (two cetacean and three
pinniped [two otariid and one phocid] species) with expected potential
to co-occur with Port construction activities. Please refer to Table 1.
The two cetacean species that may be present are classified as high-
frequency.
Acoustic Effects, Underwater
Potential Effects of Pile Driving Sound--The effects of sounds from
pile driving might result in one or more of the following: temporary or
permanent hearing impairment, non-auditory physical or physiological
effects, behavioral disturbance, and masking (Richardson et al., 1995;
Gordon et al., 2004; Nowacek et al., 2007; Southall et al., 2007). The
effects of pile driving on marine mammals are dependent on several
factors, including the size, type, and depth of the animal; the depth,
intensity, and duration of the pile driving sound; the depth of the
water column; the substrate of the habitat; the standoff distance
between the pile and
[[Page 43411]]
the animal; and the sound propagation properties of the environment.
Impacts to marine mammals from pile driving activities are expected to
result primarily from acoustic pathways. As such, the degree of effect
is intrinsically related to the received level and duration of the
sound exposure, which are in turn influenced by the distance between
the animal and the source. The further away from the source, the less
intense the exposure should be. The substrate and depth of the habitat
affect the sound propagation properties of the environment. Shallow
environments are typically more structurally complex, which leads to
rapid sound attenuation. In addition, substrates that are soft (e.g.,
sand) would absorb or attenuate the sound more readily than hard
substrates (e.g., rock) which may reflect the acoustic wave. Soft
porous substrates would also likely require less time to drive the
pile, and possibly less forceful equipment, which would ultimately
decrease the intensity of the acoustic source.
In the absence of mitigation, impacts to marine species would be
expected to result from physiological and behavioral responses to both
the type and strength of the acoustic signature (Viada et al., 2008).
The type and severity of behavioral impacts are more difficult to
define due to limited studies addressing the behavioral effects of
impulsive sounds on marine mammals. Potential effects from impulsive
sound sources can range in severity from effects such as behavioral
disturbance or tactile perception to physical discomfort, slight injury
of the internal organs and the auditory system, or mortality (Yelverton
et al., 1973).
Hearing Impairment and Other Physical Effects--Marine mammals
exposed to high intensity sound repeatedly or for prolonged periods can
experience hearing threshold shift (TS), which is the loss of hearing
sensitivity at certain frequency ranges (Kastak et al., 1999; Schlundt
et al., 2000; Finneran et al., 2002, 2005). TS can be permanent (PTS),
in which case the loss of hearing sensitivity is not recoverable, or
temporary (TTS), in which case the animal's hearing threshold would
recover over time (Southall et al., 2007). Marine mammals depend on
acoustic cues for vital biological functions, (e.g., orientation,
communication, finding prey, avoiding predators); thus, TTS may result
in reduced fitness in survival and reproduction. However, this depends
on the frequency and duration of TTS, as well as the biological context
in which it occurs. TTS of limited duration, occurring in a frequency
range that does not coincide with that used for recognition of
important acoustic cues, would have little to no effect on an animal's
fitness. Repeated sound exposure that leads to TTS could cause PTS. PTS
constitutes injury, but TTS does not (Southall et al., 2007). The
following subsections discuss in somewhat more detail the possibilities
of TTS, PTS, and non-auditory physical effects.
Temporary Threshold Shift--TTS is the mildest form of hearing
impairment that can occur during exposure to a strong sound (Kryter,
1985). While experiencing TTS, the hearing threshold rises, and a sound
must be stronger in order to be heard. In terrestrial mammals, TTS can
last from minutes or hours to days (in cases of strong TTS). For sound
exposures at or somewhat above the TTS threshold, hearing sensitivity
in both terrestrial and marine mammals recovers rapidly after exposure
to the sound ends. Few data on sound levels and durations necessary to
elicit mild TTS have been obtained for marine mammals, and none of the
published data concern TTS elicited by exposure to multiple pulses of
sound. Available data on TTS in marine mammals are summarized in
Southall et al. (2007).
Given the available data, the received level of a single pulse
(with no frequency weighting) might need to be approximately 186 dB re
1 [mu]Pa\2\-s (i.e., 186 dB sound exposure level [SEL] or approximately
221-226 dB p-p [peak]) in order to produce brief, mild TTS. Exposure to
several strong pulses that each have received levels near 190 dB rms
(175-180 dB SEL) might result in cumulative exposure of approximately
186 dB SEL and thus slight TTS in a small odontocete, assuming the TTS
threshold is (to a first approximation) a function of the total
received pulse energy.
The above TTS information for odontocetes is derived from studies
on the bottlenose dolphin (Tursiops truncatus) and beluga whale
(Delphinapterus leucas). There is no published TTS information for
other species of cetaceans. However, preliminary evidence from a harbor
porpoise exposed to pulsed sound suggests that its TTS threshold may
have been lower (Lucke et al., 2009). As summarized above, data that
are now available imply that TTS is unlikely to occur unless
odontocetes are exposed to pile driving pulses stronger than 180 dB re
1 [mu]Pa rms.
Permanent Threshold Shift--When PTS occurs, there is physical
damage to the sound receptors in the ear. In severe cases, there can be
total or partial deafness, while in other cases the animal has an
impaired ability to hear sounds in specific frequency ranges (Kryter,
1985). There is no specific evidence that exposure to pulses of sound
can cause PTS in any marine mammal. However, given the possibility that
mammals close to a sound source can incur TTS, it is possible that some
individuals might incur PTS. Single or occasional occurrences of mild
TTS are not indicative of permanent auditory damage, but repeated or
(in some cases) single exposures to a level well above that causing TTS
onset might elicit PTS.
Relationships between TTS and PTS thresholds have not been studied
in marine mammals but are assumed to be similar to those in humans and
other terrestrial mammals, based on anatomical similarities. PTS might
occur at a received sound level at least several decibels above that
inducing mild TTS if the animal were exposed to strong sound pulses
with rapid rise time. Based on data from terrestrial mammals, a
precautionary assumption is that the PTS threshold for impulse sounds
(such as pile driving pulses as received close to the source) is at
least 6 dB higher than the TTS threshold on a peak-pressure basis and
probably greater than 6 dB (Southall et al., 2007). On an SEL basis,
Southall et al. (2007) estimated that received levels would need to
exceed the TTS threshold by at least 15 dB for there to be risk of PTS.
Thus, for cetaceans, Southall et al. (2007) estimate that the PTS
threshold might be an M-weighted SEL (for the sequence of received
pulses) of approximately 198 dB re 1 [mu]Pa\2\-s (15 dB higher than the
TTS threshold for an impulse). Given the higher level of sound
necessary to cause PTS as compared with TTS, it is considerably less
likely that PTS could occur.
Measured source levels from impact pile driving can be as high as
214 dB rms. Although no marine mammals have been shown to experience
TTS or PTS as a result of being exposed to pile driving activities,
captive bottlenose dolphins and beluga whales exhibited changes in
behavior when exposed to strong pulsed sounds (Finneran et al., 2000,
2002, 2005). The animals tolerated high received levels of sound before
exhibiting aversive behaviors. Experiments on a beluga whale showed
that exposure to a single watergun impulse at a received level of 207
kPa (30 psi) p-p, which is equivalent to 228 dB p-p, resulted in a 7
and 6 dB TTS in the beluga whale at 0.4 and 30 kHz, respectively.
Thresholds returned to within 2 dB of the pre-exposure level within
four minutes of the exposure (Finneran et al., 2002). Although the
source level of pile driving from one
[[Page 43412]]
hammer strike is expected to be much lower than the single watergun
impulse cited here, animals being exposed for a prolonged period to
repeated hammer strikes could receive more sound exposure in terms of
SEL than from the single watergun impulse (estimated at 188 dB re 1
[mu]Pa\2\-s) in the aforementioned experiment (Finneran et al., 2002).
However, in order for marine mammals to experience TTS or PTS, the
animals have to be close enough to be exposed to high intensity sound
levels for a prolonged period of time. Based on the best scientific
information available, these SPLs are far below the thresholds that
could cause TTS or the onset of PTS.
Non-auditory Physiological Effects--Non-auditory physiological
effects or injuries that theoretically might occur in marine mammals
exposed to strong underwater sound include stress, neurological
effects, bubble formation, resonance effects, and other types of organ
or tissue damage (Cox et al., 2006; Southall et al., 2007). Studies
examining such effects are limited. In general, little is known about
the potential for pile driving to cause auditory impairment or other
physical effects in marine mammals. Available data suggest that such
effects, if they occur at all, would presumably be limited to short
distances from the sound source and to activities that extend over a
prolonged period. The available data do not allow identification of a
specific exposure level above which non-auditory effects can be
expected (Southall et al., 2007) or any meaningful quantitative
predictions of the numbers (if any) of marine mammals that might be
affected in those ways. Marine mammals that show behavioral avoidance
of pile driving, including some odontocetes and some pinnipeds, are
especially unlikely to incur auditory impairment or non-auditory
physical effects.
Disturbance Reactions
Disturbance includes a variety of effects, including subtle changes
in behavior, more conspicuous changes in activities, and displacement.
Behavioral responses to sound are highly variable and context-specific
and reactions, if any, depend on species, state of maturity,
experience, current activity, reproductive state, auditory sensitivity,
time of day, and many other factors (Richardson et al., 1995; Wartzok
et al., 2003; Southall et al., 2007).
Habituation can occur when an animal's response to a stimulus wanes
with repeated exposure, usually in the absence of unpleasant associated
events (Wartzok et al., 2003). Animals are most likely to habituate to
sounds that are predictable and unvarying. The opposite process is
sensitization, when an unpleasant experience leads to subsequent
responses, often in the form of avoidance, at a lower level of
exposure. Behavioral state may affect the type of response as well. For
example, animals that are resting may show greater behavioral change in
response to disturbing sound levels than animals that are highly
motivated to remain in an area for feeding (Richardson et al., 1995;
NRC, 2003; Wartzok et al., 2003).
Controlled experiments with captive marine mammals showed
pronounced behavioral reactions, including avoidance of loud sound
sources (Ridgway et al., 1997; Finneran et al., 2003). Observed
responses of wild marine mammals to loud pulsed sound sources
(typically seismic guns or acoustic harassment devices, but also
including pile driving) have been varied but often consist of avoidance
behavior or other behavioral changes suggesting discomfort (Morton and
Symonds, 2002; Thorson and Reyff, 2006; see also Gordon et al., 2004;
Wartzok et al., 2003; Nowacek et al., 2007). Responses to continuous
sound, such as vibratory pile installation, have not been documented as
well as responses to pulsed sounds.
With both types of pile driving, it is likely that the onset of
pile driving could result in temporary, short term changes in an
animal's typical behavior and/or avoidance of the affected area. These
behavioral changes may include (Richardson et al., 1995): 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; and/or flight responses (e.g.,
pinnipeds flushing into water from haul-outs or rookeries). Pinnipeds
may increase their haul-out time, possibly to avoid in-water
disturbance (Thorson and Reyff, 2006).
The biological significance of many of these behavioral
disturbances is difficult to predict, especially if the detected
disturbances appear minor. However, the consequences of behavioral
modification could be expected to be biologically significant if the
change affects growth, survival, or reproduction. Significant
behavioral modifications that could potentially lead to effects on
growth, survival, or reproduction include:
Drastic changes in diving/surfacing patterns (such as
those thought to cause beaked whale stranding due to exposure to
military mid-frequency tactical sonar);
Habitat abandonment due to loss of desirable acoustic
environment; and
Cessation of feeding or social interaction.
The onset of behavioral disturbance from anthropogenic sound
depends on both external factors (characteristics of sound sources and
their paths) and the specific characteristics of the receiving animals
(hearing, motivation, experience, demography) and is difficult to
predict (Southall et al., 2007).
Auditory Masking
Natural and artificial sounds can disrupt behavior by masking, or
interfering with, a marine mammal's ability to hear other sounds.
Masking occurs when the receipt of a sound is interfered with by
another coincident sound at similar frequencies and at similar or
higher levels. Chronic exposure to excessive, though not high-
intensity, sound could cause masking at particular frequencies for
marine mammals that utilize sound for vital biological functions.
Masking can interfere with detection of acoustic signals such as
communication calls, echolocation sounds, and environmental sounds
important to marine mammals. Therefore, under certain circumstances,
marine mammals whose acoustical sensors or environment are being
severely masked could also be impaired from maximizing their
performance fitness in survival and reproduction. If the coincident
(masking) sound were anthropogenic, it could be potentially harassing
if it disrupted hearing-related behavior. It is important to
distinguish TTS and PTS, which persist after the sound exposure, from
masking, which occurs only during the sound exposure. Because masking
(without resulting in TS) is not associated with abnormal physiological
function, it is not considered a physiological effect, but rather a
potential behavioral effect.
The frequency range of the potentially masking sound is important
in determining any potential behavioral impacts. Because sound
generated from in-water pile driving is mostly concentrated at low
frequency ranges, it may have less effect on high frequency
echolocation sounds made by porpoises. However, lower frequency man-
made sounds are more likely to affect detection of communication calls
and other potentially important natural sounds such as surf and prey
sound. It may also affect communication signals
[[Page 43413]]
when they occur near the sound band and thus reduce the communication
space of animals (e.g., Clark et al., 2009) and cause increased stress
levels (e.g., Foote et al., 2004; Holt et al., 2009).
Masking has the potential to impact species at the population or
community levels as well as at individual levels. Masking affects both
senders and receivers of the signals and can potentially have long-term
chronic effects on marine mammal species and populations. Recent
research suggests that low frequency ambient sound levels have
increased by as much as 20 dB (more than three times in terms of SPL)
in the world's ocean from pre-industrial periods, and that most of
these increases are from distant shipping (Hildebrand, 2009). All
anthropogenic sound sources, such as those from vessel traffic, pile
driving, and dredging activities, contribute to the elevated ambient
sound levels, thus intensifying masking.
Vibratory pile driving is relatively short-term, with rapid
oscillations occurring for approximately sixty minutes per installed
pile. It is possible that vibratory pile driving resulting from this
proposed action may mask acoustic signals important to the behavior and
survival of marine mammal species, but the short-term duration and
limited affected area would result in insignificant impacts from
masking. Any masking event that could possibly rise to Level B
harassment under the MMPA would occur concurrently within the zones of
behavioral harassment already estimated for vibratory pile driving, and
which have already been taken into account in the exposure analysis.
Acoustic Effects, Airborne
Marine mammals that occur in the project area could be exposed to
airborne sounds associated with pile driving that have the potential to
cause harassment, depending on their distance from pile driving
activities. Airborne pile driving sound would have less impact on
cetaceans than pinnipeds because sound from atmospheric sources does
not transmit well underwater (Richardson et al., 1995); thus, airborne
sound would only be an issue for pinnipeds either hauled-out or looking
with heads above water in the project area. 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 their habitat and move further from the source. Studies by
Blackwell et al. (2004) and Moulton et al. (2005) indicate a tolerance
or lack of response to unweighted airborne sounds as high as 112 dB
peak and 96 dB rms.
Anticipated Effects on Habitat
The proposed activities at Friday Harbor would not result in
permanent impacts to habitats used directly by marine mammals, such as
haul-out sites, and is unlikely to have even short-term impacts to food
sources such as forage fish as impact driving is not proposed for this
project. There are no rookeries or major haul-out sites nearby (there
are rocks used by harbor seals as haul-outs within the acoustic zone of
influence, approximately 5 km from the project site) or ocean bottom
structure of significant biological importance to marine mammals that
may be present in the marine waters in the vicinity of the project
area. Therefore, the main impact associated with the proposed activity
would be temporarily elevated sound levels and the associated direct
effects on marine mammals, as discussed previously in this document.
The most likely impact to marine mammal habitat occurs from minor
impacts to the immediate substrate during installation and removal of
piles during the project.
Potential Pile Driving Effects on Prey
Construction activities would produce continuous (i.e., vibratory
pile driving) sounds. Fish react to sounds which are especially strong
and/or intermittent low-frequency sounds. Short duration, sharp sounds
can cause overt or subtle changes in fish behavior and local
distribution. Hastings and Popper (2005) identified several studies
that suggest fish may relocate to avoid certain areas of sound energy.
Additional studies have documented effects of pile driving on fish,
although several are based on studies in support of large, multiyear
bridge construction projects (e.g., Scholik and Yan, 2001, 2002; Popper
and Hastings, 2009). Sound pulses at received levels of 160 dB may
cause subtle changes in fish behavior. SPLs of 180 dB may cause
noticeable changes in behavior (Pearson et al., 1992; Skalski et al.,
1992). SPLs of sufficient strength have been known to cause injury to
fish and fish mortality. The most likely impact to fish from pile
driving activities at the project area would be temporary behavioral
avoidance of the area. The duration of fish avoidance of this area
after pile driving stops is unknown, but a rapid return to normal
recruitment, distribution and behavior is anticipated. In general,
impacts to marine mammal prey species are expected to be minor and
temporary due to the short timeframe for the project and lack of impact
pile driving.
Pile Driving Effects on Potential Foraging Habitat
The area likely impacted by the project is relatively small
compared to the available habitat in the San Juan Islands. Avoidance by
potential prey (i.e., fish) of the immediate area due to the temporary
loss of this foraging habitat is also possible. The duration of fish
avoidance of this area after pile driving stops is unknown, but a rapid
return to normal recruitment, distribution and behavior is anticipated.
Any behavioral avoidance by fish of the disturbed area would still
leave significantly large areas of fish and marine mammal foraging
habitat in the nearby vicinity.
In summary, given the short daily duration of sound associated with
individual pile driving events, the relatively small areas being
affected, and the absence of impact pile driving, pile driving
activities associated with the proposed action are not likely to have a
permanent, adverse effect on any fish habitat, or populations of fish
species. Thus, any impacts to marine mammal habitat are not expected to
cause significant or long-term consequences for individual marine
mammals or their populations.
Proposed Mitigation
In order to issue an IHA under Section 101(a)(5)(D) of the MMPA,
NMFS must set forth the permissible methods of taking pursuant to such
activity, ``and other means of effecting the least practicable impact
on such species or stock and its habitat, paying particular attention
to rookeries, mating grounds, and areas of similar significance, and on
the availability of such species or stock for taking'' for certain
subsistence uses.
Measurements from similar pile driving events were coupled with
practical spreading loss to estimate zones of influence (ZOI; see
``Estimated Take by Incidental Harassment''). ZOIs are often used to
establish a mitigation zone around each pile to prevent Level A
harassment to marine mammals, and also provide estimates of the areas
within which Level B harassment might occur. ZOIs may vary between
different diameter piles and types of installation methods. In addition
to the measures described later in this section, the Port would employ
the following standard mitigation measures:
(a) Conduct briefings between construction supervisors and crews,
marine mammal monitoring team, and Port staff prior to the start of all
pile
[[Page 43414]]
driving activity, and when new personnel join the work, in order to
explain responsibilities, communication procedures, marine mammal
monitoring protocol, and operational procedures.
(b) For in-water heavy machinery work other than pile driving
(using, e.g., standard barges, tug boats, barge-mounted excavators, or
clamshell equipment used to place or remove material), if a marine
mammal comes within 10 m, operations shall cease and vessels shall
reduce speed to the minimum level required to maintain steerage and
safe working conditions. This type of work could include the following
activities: (1) Movement of the barge to the pile location; (2)
positioning of the pile on the substrate via a crane (i.e., stabbing
the pile); or (3) removal of the pile from the water column/substrate
via a crane (i.e., deadpull). For these activities, monitoring would
take place from 15 minutes prior to initiation until the action is
complete.
Monitoring and Shutdown for Pile Driving
The following measures would apply to the Port's mitigation through
shutdown and disturbance zones:
Shutdown Zone--For all pile driving activities, the Port will
establish a shutdown zone. Shutdown zones are intended to contain the
area in which SPLs equal or exceed the 180/190 dB rms acoustic injury
criteria, with the purpose being to define an area within which
shutdown of activity would occur upon sighting of a marine mammal (or
in anticipation of an animal entering the defined area), thus
preventing injury of marine mammals. However, the Port's activities are
not expected to produce sound at or above the 180 dB rms injury
criterion (see ``Estimated Take by Incidental Harassment''). The Port
would, however, implement a minimum shutdown zone of 10 m radius for
all marine mammals around all pile driving and removal activity. These
precautionary measures are intended to further reduce the unlikely
possibility of injury from direct physical interaction with
construction operations.
Disturbance Zone--Disturbance zones are the areas in which SPLs
equal or exceed 120 dB rms (for continuous sound) for pile driving
installation and removal. Disturbance zones provide utility for
monitoring conducted for mitigation purposes (i.e., shutdown zone
monitoring) by establishing monitoring protocols for areas adjacent to
the shutdown zones. Monitoring of disturbance zones enables observers
to be aware of and communicate the presence of marine mammals in the
project area but outside the shutdown zone and thus prepare for
potential shutdowns of activity. However, the primary purpose of
disturbance zone monitoring is for documenting incidents of Level B
harassment; disturbance zone monitoring is discussed in greater detail
later (see ``Proposed Monitoring and Reporting''). Nominal radial
distances for disturbance zones are shown in Table 3. Given the size of
the disturbance zone for vibratory pile driving, it is impossible to
guarantee that all animals would be observed or to make comprehensive
observations of fine-scale behavioral reactions to sound. We discuss
monitoring objectives and protocols in greater depth in ``Proposed
Monitoring and Reporting.''
In order to document observed incidents of harassment, monitors
record all marine mammal observations, regardless of location. The
observer's location, as well as the location of the pile being driven,
is known from a GPS. The location of the animal is estimated as a
distance from the observer, which is then compared to the location from
the pile and the estimated ZOIs for relevant activities (i.e., pile
installation and removal). This information may then be used to
extrapolate observed takes to reach an approximate understanding of
actual total takes.
Monitoring Protocols--Monitoring would be conducted before, during,
and after pile driving and 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. Observations made
outside the shutdown zone will not result in shutdown; that pile
segment would be completed without cessation, unless the animal
approaches or enters the shutdown zone, at which point all pile driving
activities would be halted. Monitoring will take place from fifteen
minutes prior to initiation through thirty minutes post-completion of
pile driving activities. Pile driving activities include the time to
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 thirty
minutes. Please see the Marine Mammal Monitoring Plan (available at
www.nmfs.noaa.gov/pr/permits/incidental.htm), developed by the Port
with our approval, for full details of the monitoring protocols.
The following additional measures apply to visual monitoring:
(1) Monitoring will be conducted by qualified observers, who will
be placed at the best vantage point(s) practicable to monitor for
marine mammals and implement shutdown/delay procedures when applicable
by calling for the shutdown to the hammer operator. Qualified observers
are trained biologists, with the following minimum qualifications:
Visual acuity in both eyes (correction is permissible)
sufficient for discernment of moving targets at the water's surface
with ability to estimate target size and distance; use of binoculars
may be necessary to correctly identify the target;
Advanced education in biological science or related field
(undergraduate degree or higher required);
Experience and ability to conduct field observations and
collect data according to assigned protocols (this may include academic
experience);
Experience or training in the field identification of
marine mammals, including the identification of behaviors;
Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
Writing skills sufficient to prepare a report of
observations including but not limited to the number and species of
marine mammals observed; dates and times when in-water construction
activities were conducted; dates and times when in-water construction
activities were suspended to avoid potential incidental injury from
construction sound of marine mammals observed within a defined shutdown
zone; and marine mammal behavior; and
Ability to communicate orally, by radio or in person, with
project personnel to provide real-time information on marine mammals
observed in the area as necessary.
(2) Prior to the start of pile driving activity, the shutdown zone
will be monitored for fifteen minutes to ensure that it is clear of
marine mammals. Pile driving will only commence once observers have
declared the shutdown zone clear of marine mammals; animals will be
allowed to remain in the shutdown zone (i.e., must leave of their own
volition) and their behavior will be monitored and documented. The
shutdown zone may only be declared clear, and pile driving started,
when the entire shutdown zone is visible (i.e., when not obscured by
dark, rain, fog, etc.). In addition, if such conditions should arise
during impact pile driving that is already underway, the activity would
be halted.
(3) If a marine mammal approaches or enters the shutdown zone
during the course of pile driving operations,
[[Page 43415]]
activity will be halted and delayed until either the animal has
voluntarily left and been visually confirmed beyond the shutdown zone
or fifteen minutes have passed without re-detection of the animal.
Monitoring will be conducted throughout the time required to drive a
pile.
Timing Restrictions
In the San Juan Islands, designated timing restrictions exist for
pile driving activities to avoid in-water work when salmonids are
likely to be present. The in-water work window is July 16-February 15,
although work will not begin prior to September 1. In-water
construction activities will occur during daylight hours (sunrise to
sunset).
Soft Start
The use of a soft-start procedure is believed to provide additional
protection to marine mammals by warning or providing a chance to leave
the area prior to the hammer operating at full capacity, and typically
involves a requirement to initiate sound from vibratory hammers for
fifteen seconds at reduced energy followed by a thirty-second waiting
period. This procedure is repeated two additional times.
We have carefully evaluated the Port's proposed mitigation measures
and considered their effectiveness in past implementation to
preliminarily determine whether they are likely to effect the least
practicable impact on the affected marine mammal species and stocks and
their habitat. Our evaluation of potential measures included
consideration of the following factors in relation to one another: (1)
The manner in which, and the degree to which, the successful
implementation of the measure is expected to minimize adverse impacts
to marine mammals, (2) the proven or likely efficacy of the specific
measure to minimize adverse impacts as planned; and (3) the
practicability of the measure for applicant implementation.
Any mitigation measure(s) we prescribe should be able to
accomplish, have a reasonable likelihood of accomplishing (based on
current science), or contribute to the accomplishment of one or more of
the general goals listed below:
(1) Avoidance or minimization of injury or death of marine mammals
wherever possible (goals 2, 3, and 4 may contribute to this goal).
(2) A reduction in the number (total number or number at
biologically important time or location) of individual marine mammals
exposed to stimuli expected to result in incidental take (this goal may
contribute to 1, above, or to reducing takes by behavioral harassment
only).
(3) A reduction in the number (total number or number at
biologically important time or location) of times any individual marine
mammal would be exposed to stimuli expected to result in incidental
take (this goal may contribute to 1, above, or to reducing takes by
behavioral harassment only).
(4) A reduction in the intensity of exposure to stimuli expected to
result in incidental take (this goal may contribute to 1, above, or to
reducing the severity of behavioral harassment only).
(5) Avoidance or minimization of adverse effects to marine mammal
habitat, paying particular attention to the prey base, blockage or
limitation of passage to or from biologically important areas,
permanent destruction of habitat, or temporary disturbance of habitat
during a biologically important time.
(6) For monitoring directly related to mitigation, an increase in
the probability of detecting marine mammals, thus allowing for more
effective implementation of the mitigation.
Based on our evaluation of the Port's proposed measures, including
information from monitoring of implementation of mitigation measures
very similar to those described here under previous IHAs for other
similar projects in Washington inland waters, including work conducted
at Friday Harbor by the Washington State Department of Transportation,
we have preliminarily determined that the proposed mitigation measures
provide the means of effecting the least practicable impact on marine
mammal 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
incidental take 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.
Any monitoring requirement we prescribe should improve our
understanding of one or more of the following:
Occurrence of marine mammal species in action area (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 responses to acute stressors, or impacts of
chronic exposures (behavioral or physiological).
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of an individual; or (2) Population,
species, or stock.
Effects on marine mammal habitat and resultant impacts to
marine mammals.
Mitigation and monitoring effectiveness.
The Port submitted a marine mammal monitoring plan as part of the
IHA application for this project, which can be found on the Internet at
www.nmfs.noaa.gov/pr/permits/incidental.htm. Although this plan was
initially developed as part of the ESA consultation process (with NMFS'
West Coast Regional Office) to enable the Port to cease activities in
the event that ESA-listed species occur in the project vicinity, the
plan is applicable to all marine mammals that may occur in the action
area. The plan may be modified or supplemented based on comments or new
information received from the public during the public comment period.
Visual Marine Mammal Observations
The Port will collect sighting data and behavioral responses to
construction for marine mammal species observed in the region of
activity during the period of activity. All observers will be trained
in marine mammal identification and behaviors and are required to have
no other construction-related tasks while conducting monitoring. The
Port will monitor the shutdown zone and disturbance zone before,
during, and after pile driving and removal, with observers located at
the best practicable vantage points. Based on our requirements, the
Marine Mammal Monitoring Plan would implement the following procedures
for pile driving:
MMOs would be located at the best vantage point(s) in
order to properly see
[[Page 43416]]
the entire shutdown zone and as much of the disturbance zone as
possible. During vibratory driving, a minimum of four MMOs will be
deployed, including two shore-based (with one of these located
appropriately to focus on the shutdown zone) and two vessel-based.
Please see Figure 2 of the Port's plan. During vibratory removal, a
minimum of three observers shall be deployed at the best vantage points
to observe the shutdown and disturbance zones.
During all observation periods, observers will use
binoculars and the naked eye to search continuously for marine mammals.
If the shutdown zones are obscured by fog or poor lighting
conditions, pile driving at that location will not be initiated until
that zone is visible.
The shutdown and disturbance zones around the pile will be
monitored for the presence of marine mammals before, during, and after
any pile driving or removal activity.
Individuals implementing the monitoring protocol will assess its
effectiveness using an adaptive approach. Monitoring biologists will
use their best professional judgment throughout implementation and seek
improvements to these methods when deemed appropriate. Any
modifications to protocol will be coordinated between NMFS and the
Port.
Although we have determined that incidental take of multiple
species with recorded occurrence in the action area (e.g., killer
whales, humpback whales) is unlikely (see ``Estimated Take by
Incidental Harassment''), the Port's monitoring plan will provide
additional protections against the unauthorized take of these species.
While it is difficult to say with certainty that smaller cetaceans or
pinnipeds would always be detected in an area as large as the typical
ZOI for vibratory driving (in this case estimated at 6.7 km\2\), we do
believe that there is a high degree of certainty that large whales
would be detected. Therefore, in the event that humpback whales, gray
whales, minke whales, or killer whales occurred in the project area,
the Port would be able to detect those animals and cease construction
activity as necessary to avoid unauthorized take. The Port will also
consult available sighting networks (e.g., Orca Network) on a daily
basis while pile installation and removal is occurring for situational
awareness of large whale occurrence in the general vicinity of Friday
Harbor, such that MMOs know when there is the increased possibility for
such species to be present.
Data Collection
We require that observers use approved data forms. Among other
pieces of information, the Port will record detailed information about
any implementation of shutdowns, including the distance of animals to
the pile and description of specific actions that ensued and resulting
behavior of the animal, if any. In addition, the Port will attempt to
distinguish between the number of individual animals taken and the
number of incidents of take. We require that, at a minimum, the
following information be collected on the sighting forms:
Date and time that monitored activity begins or ends;
Construction activities occurring during each observation
period;
Weather parameters (e.g., percent cover, visibility);
Water conditions (e.g., sea state, tide state);
Species, numbers, and, if possible, sex and age class of
marine mammals;
Description of any observable marine mammal behavior
patterns, including bearing and direction of travel and distance from
pile driving activity;
Distance from pile driving activities to marine mammals
and distance from the marine mammals to the observation point;
Locations of all marine mammal observations; and
Other human activity in the area.
Reporting
A draft report would be submitted within ninety calendar days of
the completion of the in-water work window. The report will include
marine mammal observations pre-activity, during-activity, and post-
activity during pile driving days, and will also provide descriptions
of any problems encountered in deploying sound attenuating devices, any
behavioral responses to construction activities by marine mammals and a
complete description of all mitigation shutdowns and the results of
those actions and an extrapolated total take estimate based on the
number of marine mammals observed during the course of construction. A
final report must be submitted within thirty days following resolution
of comments on the draft report.
Estimated Take by Incidental Harassment
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].''
All anticipated takes would be by Level B harassment resulting from
vibratory pile driving/removal and involving temporary changes in
behavior. Injurious or lethal takes are not expected due to the
expected source levels and sound source characteristics associated with
the activity, and the proposed mitigation and monitoring measures are
expected to further minimize the possibility of such take.
If a marine mammal responds to a stimulus by changing its behavior
(e.g., through relatively minor changes in locomotion direction/speed
or vocalization behavior), the response may or may not constitute
taking at the individual level, and is unlikely to affect the stock or
the species as a whole. However, if a sound source displaces marine
mammals from an important feeding or breeding area for a prolonged
period, impacts on animals or on the stock or species could potentially
be significant (e.g., Lusseau and Bejder, 2007; Weilgart, 2007). Given
the many uncertainties in predicting the quantity and types of impacts
of sound on marine mammals, it is common practice to estimate how many
animals are likely to be present within a particular distance of a
given activity, or exposed to a particular level of sound.
This practice potentially overestimates the numbers of marine
mammals taken because it is often difficult to distinguish between the
individuals harassed and incidences of harassment. In particular, for
stationary activities, it is more likely that some smaller number of
individuals may accrue a number of incidences of harassment per
individual than for each incidence to accrue to a new individual,
especially if those individuals display some degree of residency or
site fidelity and the impetus to use the site (e.g., because of
foraging opportunities) is stronger than the deterrence presented by
the harassing activity.
The project area is not believed to be particularly important
habitat for marine mammals, nor is it considered an area frequented by
marine mammals. Therefore, behavioral disturbances that could result
from anthropogenic sound associated with these activities are expected
to affect only a relatively small number of individual marine mammals,
[[Page 43417]]
although those effects could be recurring over the life of the project
if the same individuals remain in the project vicinity. Specifically,
at Friday Harbor marina there is a known individual harbor seal that
the Port believes is unlikely to respond to harassing stimuli in
aversive manner, meaning the seal is believed likely to simply remain
in the immediate vicinity of the marina and be exposed to sound (either
airborne or underwater) at or above levels that we consider to incur
incidental take. This is accounted for in estimating incidental take
for harbor seals below.
The Port has requested authorization for the incidental taking of
small numbers of Steller sea lions, California sea lions, harbor seals,
Dall's porpoises, and harbor porpoises near Friday Harbor that may
result from pile driving during construction activities associated with
the marina reconstruction project described previously in this
document. In order to estimate the potential incidents of take that may
occur incidental to the specified activity, we must first estimate the
extent of the sound field that may be produced by the activity and then
consider in combination with information about marine mammal density or
abundance in the project area. We first provide information on
applicable sound thresholds for determining effects to marine mammals
before describing the information used in estimating the sound fields,
the available marine mammal density or abundance information, and the
method of estimating potential incidences of take.
Sound Thresholds
We use generic sound exposure thresholds to determine when an
activity that produces sound might result in impacts to a marine mammal
such that a take by harassment might occur. To date, no studies have
been conducted that explicitly examine impacts to marine mammals from
pile driving sounds or from which empirical sound thresholds have been
established. These thresholds (Table 3) are used to estimate when
harassment may occur (i.e., when an animal is exposed to levels equal
to or exceeding the relevant criterion) in specific contexts; however,
useful contextual information that may inform our assessment of effects
is typically lacking and we consider these thresholds as step
functions. NMFS is working to revise these acoustic guidelines; for
more information on that process, please visit www.nmfs.noaa.gov/pr/acoustics/guidelines.htm.
Table 3--Current Acoustic Exposure Criteria
------------------------------------------------------------------------
Criterion Definition Threshold
------------------------------------------------------------------------
Level A harassment (underwater). Injury (PTS--any 180 dB (cetaceans)/
level above that 190 dB
which is known to (pinnipeds)
cause TTS). (rms).
Level B harassment (underwater). Behavioral 160 dB (impulsive
disruption. source)/120 dB
(continuous
source) (rms).
Level B harassment (airborne)*.. Behavioral 90 dB (harbor
disruption. seals)/100 dB
(other pinnipeds)
(unweighted).
------------------------------------------------------------------------
* NMFS has not established any formal criteria for harassment resulting
from exposure to airborne sound. However, these thresholds represent
the best available information regarding the effects of pinniped
exposure to such sound and NMFS' practice is to associate exposure at
these levels with Level B harassment.
Distance to Sound Thresholds
Underwater Sound Propagation Formula--Pile driving generates
underwater noise that can potentially result in disturbance to marine
mammals in the project area. 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
R1 = the distance of the modeled SPL from the driven
pile, and
R2 = the distance from the driven pile of the initial
measurement.
This formula neglects loss due to scattering and absorption, which is
assumed to be zero here. The degree to which underwater sound
propagates away from a sound source is dependent on a variety of
factors, most notably the water bathymetry and presence or absence of
reflective or absorptive conditions including in-water structures and
sediments. Spherical spreading occurs in a perfectly unobstructed
(free-field) environment not limited by depth or water surface,
resulting in a 6 dB reduction in sound level for each doubling of
distance from the source (20*log[range]). Cylindrical spreading occurs
in an environment in which sound propagation is bounded by the water
surface and sea bottom, resulting in a reduction of 3 dB in sound level
for each doubling of distance from the source (10*log[range]). A
practical spreading value of fifteen is often used under conditions,
such as Friday Harbor, where water increases with depth as the receiver
moves away from the shoreline, resulting in an expected propagation
environment that would lie between spherical and cylindrical spreading
loss conditions. Practical spreading loss (4.5 dB reduction in sound
level for each doubling of distance) is assumed here.
Underwater Sound--The intensity of pile driving sounds is greatly
influenced by factors such as the type of piles, hammers, and the
physical environment in which the activity takes place. A large
quantity of literature regarding SPLs recorded from pile driving
projects is available for consideration. In order to determine
reasonable SPLs and their associated effects on marine mammals that are
likely to result from pile driving at Friday Harbor, studies with
similar properties to the specified activity were evaluated. The Port
plans to install 16- and 24-in steel pipe piles via vibratory driver
and to remove 12- and 20-in timber piles, as well as several 12-in
steel pipe piles, via vibratory methods. We rely on measurement
conducted previously by WSDOT for similar activities in similar
locations for proxy source levels. Data were collected during vibratory
pile driving of 24-in diameter steel piles at the Friday Harbor Ferry
Terminal (immediately adjacent to the Friday Harbor marina) facility
during January 2005 (Laughlin, 2010). The average SPL was measured as
162 dB rms at 10 m from the pile. For comparison, Caltrans (2012)
reports summary values of 155 dB rms and 170 dB rms (at 10 m distance
from source) for 12- and 36-in steel pipe piles, respectively. They do
not report a value for 24-in diameter steel pipe piles. The vibratory
removal of 12-in timber piles was measured at the Port Townsend
[[Page 43418]]
Ferry Terminal during December 2010, with an average SPL of 150 dB rms
recorded at 16 m from the source (Laughlin, 2011). This is the only
measurement we are aware of for vibratory pile removal and, although
the 20-in diameter piles to be removed by the Port are larger, it is
not expected that a slightly larger pile size would result in
meaningfully greater SPLs for vibratory pile removal. Vibratory pile
removal involves only very brief vibration of the pile to be removed
such that liquefaction of the surrounding substrate is achieved. Pile
size is not a critical factor here.
All calculated distances to and the total area encompassed by the
120-dB marine mammal sound threshold for the two activities are
provided in Table 4. The Port used source values of 177 dB rms for
vibratory driving and 168 dB rms for vibratory removal. Because these
values are below the 180/190 dB rms injury criteria, there are no zones
within which injury would be expected to occur as a result of exposure
to underwater sound. Please see also Figure 1-3 of the Port's
application for a spatial representation of these zones in relation to
local topography, which constrains the actual sound field from reaching
the estimated radial distance to threshold for vibratory driving, and
in certain directions for vibratory removal. The maximum line of sight
distance that may be reached from the Friday Harbor marina before
encountering land is approximately 4 km.
Table 4--Calculated Distance(s) to and Area Encompassed by Underwater
Marine Mammal Sound Thresholds During Pile Installation
------------------------------------------------------------------------
Distance
Threshold \1\ Area
------------------------------------------------------------------------
Vibratory driving, disturbance (120 dB)......... 6.3 km \2\ 6.7 km
Vibratory removal, disturbance (120 dB)......... 1.6 km \2\ 1.8 km
------------------------------------------------------------------------
\1\ Radial distances presented for reference only. Maximum line of sight
distance from Friday Harbor before encountering land is approximately
4 km. Please refer to Figure 1-3 in the Port's application.
Airborne Sound--Pile driving can generate airborne sound that could
potentially result in disturbance to marine mammals (specifically,
pinnipeds) that are hauled out or at the water's surface with heads
above the water (see Table 3). The Port has estimated that airborne
noise produced by vibratory pile driving might attenuate to 90 dB rms
(unweighted) within approximately 30 m. However, because there are no
regular haul-outs within such a small area around the site of proposed
pile driving activity, we believe that incidents of incidental take
resulting solely from airborne sound are unlikely. It is possible that
a pinniped could occur within that zone, either in water or hauled out
on some structure, and thereby be exposed to levels of airborne sound
that we associate with harassment, but any such happenstance occurrence
would likely be accounted for in our estimation of incidental take from
underwater sound. The one exception is the known individual harbor seal
that tends to remain at the marina. There is the potential for this
individual animal to remain hauled out during construction activity,
and therefore be exposed solely to airborne sound. We have accounted
specifically for this individual, but do not propose to authorize any
take of marine mammals due solely to airborne sound, while recognizing
that pinnipeds occurring within this estimated 30-m radius zone could
experience harassment as a result of either airborne or underwater
sound. See the following discussion on harbor seals for more detail.
In summary, we recognize that pinnipeds within the estimated
airborne harassment zone, whether in the water or hauled out, could be
exposed to airborne sound that may result in behavioral harassment.
However, any animal exposed to airborne sound above the behavioral
harassment threshold is likely to also be exposed to underwater sound
above relevant thresholds (which are in all cases larger zones than
those associated with airborne sound). Thus, the behavioral harassment
of these animals is already accounted for in these estimates of
potential take. Multiple incidents of exposure to sound above NMFS'
thresholds for behavioral harassment are not believed to result in
increased behavioral disturbance, in either nature or intensity of
disturbance reaction. Therefore, we do not believe that authorization
of incidental take resulting from airborne sound for pinnipeds is
warranted, and airborne sound is not discussed further here.
Marine Mammal Densities
The Navy has developed, with input from regional marine mammal
experts, estimates of marine mammal densities in Washington inland
waters for the Navy Marine Species Density Database (NMSDD). A
technical report (Hanser et al., 2014) describes methodologies and
available information used to derive these densities, which are
generally considered the best available information for Washington
inland waters, except where specific local abundance information is
available. Here, we have determined that for all species with potential
occurrence at Friday Harbor, the Navy NMSDD information represents the
best available information for the take estimation described here. We
briefly describe the information used, but see Hanser et al. (2014) for
more detail. That document is publicly available on the Internet at
http://nwtteis.com/DocumentsandReferences/NWTTDocuments/SupportingTechnicalDocuments.aspx (accessed June 20, 2014). These
density estimates are primarily derived from available literature,
except as described below.
Description of Take Calculation
The take calculations presented here rely on the best data
currently available for marine mammal populations in the San Juan
Islands. The formula is founded on the following assumptions:
An individual can only be taken once during a 24-hour
period;
There were will be 26 total days of vibratory pile driving
with a ZOI of 6.7 km\2\ and three total days of vibratory pile removal
with a ZOI of 1.8 km\2\; and,
Exposures to sound levels above the relevant thresholds
equate to take, as defined by the MMPA.
The calculation for marine mammal takes is estimated by:
Exposure estimate = (n * ZOI) * days of total activity
Where:
n = density estimate used for each species/season
ZOI = sound threshold ZOI area; the area encompassed by all
locations where the SPLs equal or exceed the threshold being
evaluated
n * ZOI produces an estimate of the abundance of animals that could
be present in the area for exposure, and is rounded to the nearest
whole number before multiplying by days of total activity.
The ZOI impact area is estimated using the relevant distances in
Table 4, taking into consideration the possible affected area due to
topographical constraints of the action area (i.e., radial distances to
thresholds are not always reached). There are a number of reasons why
estimates of potential incidents of take may be conservative, assuming
that available density or abundance estimates and estimated ZOI areas
are accurate. We assume, in the absence of information supporting a
more refined conclusion, that the output of the calculation represents
the number of individuals that may be taken by the
[[Page 43419]]
specified activity. In fact, in the context of stationary activities
such as pile driving and in areas where resident animals may be
present, this number more realistically represents the number of
incidents of take that may accrue to a smaller number of individuals.
While pile driving can occur any day throughout the in-water work
window, and the analysis is conducted on a per day basis, only a
fraction of that time (typically a matter of hours on any given day) is
actually spent pile driving. The potential effectiveness of mitigation
measures in reducing the number of takes is typically not quantified in
the take estimation process. For these reasons, these take estimates
may be conservative. See Table 5 for total estimated incidents of take.
Note that we also provide information below for those species with
recorded occurrence in the vicinity, but for which we do not propose to
authorize take (e.g., minke whale), in order to show the basis for our
determination.
California Sea Lion--Jeffries et al. (2003) split the inland waters
geographic area into seven regions, including the San Juan Islands. The
Navy used this regional stratification as the basis for deriving
density estimates for pinnipeds occurring in inland waters. For
California sea lions, the Navy merged two regions (San Juan Islands and
Strait of Juan de Fuca) and determined the number of animals known to
use haul-outs in the combined stratum. The total number of expected
California sea lions was then divided by the area of the stratum give a
total, non-seasonal density. California sea lions are not generally
present in July (outside the work period for this proposed action).
Steller Sea Lion--Similarly, a combined San Juan Islands/Strait of
Juan de Fuca stratum was defined for Steller sea lions. The number of
animals known to use haul-outs in the stratum was then determined and
divided by the area to derive a non-seasonal density. However, Steller
sea lions are not generally present from June-September (only September
is within the work period for this proposed action).
Harbor Seal--The Navy's methodology for harbor seals follows that
described in Jeffries et al. (2003). The authors conducted aerial
surveys of harbor seals in 1999 for the Washington Department of Fish
and Wildlife, dividing the survey areas into seven strata (including
five in inland waters and two in coastal waters). To account for
animals in the water and not observed during survey counts, a
correction factor of 1.53 was applied (Huber et al., 2001) to derive a
total population for each stratum (including the San Juan Islands). The
correction factor (1.53) was based on the proportion of time seals
spend on land versus in the water over the course of a day, and was
derived by dividing one by the percentage of time harbor seals spent on
land. These data came from tags (VHF transmitters) applied to harbor
seals at six areas (Grays Harbor, Tillamook Bay, Umpqua River, Gertrude
Island, Protection/Smith Islands, and Boundary Bay, BC) within two
different harbor seal stocks (the coastal stock and the Washington
inland waters stock) over four survey years. Although the sampling
areas included both coastal and inland waters, with pooled correction
factors of 1.50 and 1.57, respectively, Huber et al. (2001) found no
significant difference in the proportion of seals ashore among the six
sites and no interannual variation at one site studied across years.
Therefore, we retain the total pooled correction factor of 1.53 here in
determining a non-seasonal density estimate for the San Juan Islands
stratum.
However, to determine an instantaneous in-water density estimate, a
secondary correction may be applied to account for harbor seals that
are hauled out at any given moment. The tagging research in 1991 and
1992 conducted by Huber et al. (2001) was repeated for two sites by
Jeffries et al. (2003), using the same methods for the 1999 and 2000
survey years. These surveys indicated that approximately 35 percent of
harbor seals are in the water versus hauled out on a daily basis (Huber
et al., 2001; Jeffries et al., 2003). A corrected density can then be
derived from the number of harbor seals that are present in the water
at any one time. In this instance, we have chosen (in consultation with
the Port) to retain the larger, uncorrected density as a precautionary
measure.
Harbor Porpoise--NMFS conducted aerial line-transect surveys in
2002 and 2003 for the purpose of estimating harbor porpoise abundance
off the coasts of Oregon, Washington, and southern British Columbia, as
well as portions of the inland waters. Survey effort was limited to sea
state conditions of Beaufort 0-2 and cloud cover less than 25 percent.
In the inland waters, the surveys covered Washington and British
Columbian waters in the Strait of Juan de Fuca, San Juan Islands, Gulf
Islands, and Strait of Georgia. To estimate the total average number of
animals sighted in each region, the number of sightings of each species
was multiplied by the average group size. For harbor porpoise,
estimates of mean group size were available on a region-specific basis
for each year. Based on the average density estimates, weighted
averages were derived to provide separate density estimates for the
eastern portion of the Strait of Juan de Fuca and San Juan Islands
region.
Dall's Porpoise--The same aerial surveys described above for harbor
porpoise were used to determine density estimates for other cetacean
species, including Dall's porpoise. For these other species, data from
the 2002-2003 surveys were prorated relative to harbor porpoise. The
number of Dall's porpoise sightings from these surveys was sufficient
to derive separate density estimates for the eastern portion of the
Strait of Juan de Fuca and San Juan Islands region.
Killer Whale--Both southern resident and west coast transient
killer whales are known to occur in the San Juan Islands. For resident
whales, photo-identification of individual whales has yielded a robust
understanding of stock structure, behavior, and movement in inland
waters. The Navy used average pod-specific seasonal residency patterns
in concert with sightings data to produce density estimates for each of
four seasons. For transient whales, monthly occurrence data were used
in concert with an estimate of average group size to produce seasonal
density estimates. For more detail on these density estimates, please
see Hanser et al. (2014). All density estimates for Washington inland
waters are presented as the results of spatial models with various
values throughout the spatial range. The numbers presented here are the
season- and range-specific maxima. For resident whales, density in the
San Juan Islands ranges from 0.0007 (winter) to 0.02 whales/km\2\
(spring through fall). For transient whales, density in the San Juan
Islands varies from 0.0006 whales/km\2\ in winter to 0.006 in summer
and 0.003 whales/km\2\ in spring/fall. For purposes of estimating the
potential for incidental take, we have used the largest density values,
which have led us to conclude that incidental take of killer whales is
unlikely. However, it is important to note the even lower potential for
occurrence in winter, when approximately half of the project would
occur.
Minke whale--Although minke whales are known to establish home
ranges in inland waters of Washington (Dorsey, 1983; Dorsey et al.,
1990), there are no published density estimates for inland waters. The
same aerial surveys described above for harbor and Dall's porpoises did
not produce sufficient sightings to derive regionally-stratified
estimates of abundance, so a single year-round density estimate was
calculated
[[Page 43420]]
for the Strait of Juan de Fuca and San Juan Islands region. This
estimate (0.02 whales/km\2\) is similar to that derived by Williams and
Thomas (2007) for other inshore waters (Strait of Georgia; 0.01 whales/
km\2\).
Gray whale--Carretta et al. (2000) provided an overall west coast
density estimate for migrating gray whales (January-April) of 0.051
whales/km\2\. The Navy then further assumes that, on the basis of
sightings data available from Orca Network (www.orcanetwork.org),
during the winter-spring migration period approximately ten percent of
migrating whales may enter the Strait of Juan de Fuca and San Juan
Islands (0.0051 whales/km\2\). During the summer/fall, when migratory
gray whales are not present, the Navy assumes that thirty percent of
the Pacific Coast Feeding Group (not discussed here but please see
Carretta et al. [2013a]) may occur within the Strait of Juan de Fuca
and San Juan Islands, also on the basis of information available
through Orca Network (0.00014 whales/km\2\). As for killer whales, we
use the higher density to estimate the potential for incidental take,
but note the lower likelihood of occurrence during a large portion of
the work period.
Humpback whale--No published density estimates are available for
humpback whales in Washington inland waters although opportunistic
sightings have increased over the last decade (as reported through Orca
Network). Based on line-transect abundance estimates for offshore
waters of Oregon and Washington (Barlow and Forney, 2007), and
consideration of opportunistic sightings recorded by the Orca Network,
the Navy assumed that the abundance estimate of humpback whales
occurring within the Strait of Juan de Fuca and the San Juan Islands
area would be twenty percent of the offshore estimates. This assumption
results in values of 0.00014 whales/km\2\ (spring through fall) and
0.00002 whales/km\2\ (winter). We note that although the higher
estimate was used to estimate the potential for incidental take, there
is a lower likelihood of occurrence during half of the work period.
Pacific white-sided dolphin--Pacific white-sided dolphins are known
to enter the inshore passes of British Columbia and Washington (Norman
et al., 2004; Stacey and Baird, 1991) and small groups have also been
seen in Haro Strait off San Juan Island, but published density
estimates are not available for these inland waters. Based on line-
transect abundance estimates for offshore waters of Oregon and
Washington (Barlow and Forney, 2007), and consideration of
opportunistic sightings recorded by the Orca Network, the Navy assumed
that the abundance estimate of Pacific white-sided dolphins occurring
within the Strait of Juan de Fuca and the San Juan Islands area during
summer/fall would be ten percent of that produced for offshore waters
(0.00248 animals/km\2\). Abundance is expected to decrease in winter/
spring, and density estimates were reduced by an order of magnitude for
this period (i.e., 0.00025 dolphins/km\2\). We note that although the
higher estimate was used to estimate the potential for incidental take,
there is a lower likelihood of occurrence during half of the work
period.
Northern elephant seal--The Navy used a combined Strait of Juan de
Fuca and San Juan Islands regional stratum and the number of animals
known to use haul-outs in that region to derive a non-seasonal density
estimate for elephant seals.
As described in the introduction to this section, we evaluate the
potential for incidental take to occur by first multiplying the most
appropriate species- and season-specific density estimate by the
relevant area of effect (ZOI). Those areas are estimated as 1.8 and 6.7
km\2\ for vibratory pile removal and vibratory pile installation,
respectively. The product of that calculation is then rounded to the
nearest whole number to estimate an instantaneous abundance within the
relevant ZOI, which is then multiplied by the number of days of the
relevant activity (three and 26 for pile removal and installation,
respectively) to arrive at an activity-specific estimate of potential
incidents of incidental take. For all species, we have used the highest
available density estimate (for either fall or winter when seasonal
estimates are available) to evaluate the potential for incidental take.
Table 5 summarizes the density estimates described above, the interim
products of the calculation, and sums to the total proposed take
authorization for each species. We have provided information for all
species that may occur in the San Juan islands, but take authorization
is proposed for only a subset of these (i.e., California and Steller
sea lions, harbor seal, and harbor and Dall's porpoises). For the
remaining species, the take estimation process indicates that
incidental take is unlikely. While we recognize that these species may
nevertheless occur in the project area, we believe that the Port's
monitoring plan further reduces the potential for any of these species
(especially the large whales, which are relatively easy to detect and
whose occurrence in the region may be noted on a daily basis through
consultation with sighting networks such as Orca Network). Finally, we
note that there is a single, known individual harbor seal that is not
expected to react to stimuli with avoidance behavior. Therefore, we
expect that there is the potential for this individual animal to remain
present through each day of construction and have added 29 takes (one
for each anticipated day of construction) to the total estimate for
harbor seals. For reasons described previously in this document, no
Level A takes would be expected (nor indicated through the take
estimation process) and no takes occurring solely via exposure to
airborne sound (with the potential exception of the known individual
described here and previously). No take authorization is proposed for
those species with a zero value in the right-hand column of Table 5,
and no Level A takes or takes solely via airborne sound are proposed
for authorization.
Table 5--Calculations for Incidental Take Estimation
--------------------------------------------------------------------------------------------------------------------------------------------------------
Estimated n * ZOI Estimated Total proposed
n * ZOI Level B takes; (vibratory Level B takes; authorized
Species n (animals/km\2\) \1\ (vibratory vibratory pile vibratory takes (% of
pile removal) removal installation) installation total stock)
--------------------------------------------------------------------------------------------------------------------------------------------------------
California sea lion....................... 0.676....................... 1.2 3 4.5 130 133 (0.04)
Steller sea lion.......................... 0.935....................... 1.7 6 6.2 156 162 (0.3)
Harbor seal............................... 3.1799...................... 5.8 18 21.2 546 \2\ 593 (4.1)
Harbor porpoise........................... 2.11226..................... 3.9 12 14.1 364 376 (3.5)
Dall's porpoise........................... 0.39........................ 0.7 3 2.6 78 81 (0.2)
Killer whale (transient).................. 0.00306 (fall).............. 0.01 0 0.02 0 0
[[Page 43421]]
Killer whale (resident)................... 0.02024 (fall).............. 0.04 0 0.1 0 0
Minke whale............................... 0.02........................ 0.04 0 0.1 0 0
Humpback whale............................ 0.00014 (fall).............. 0.0003 0 0.001 0 0
Gray whale................................ 0.0051 (winter)............. 0.01 0 0.03 0 0
Pacific white-sided dolphin............... 0.00248 (fall).............. 0.005 0 0.02 0 0
Northern elephant seal.................... 0.0063...................... 0.01 0 0.04 0 0
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\1\ Best available species- and season-specific density estimate, with season noted in parentheses where applicable.
\2\ This value includes 29 additional incidents of take to account for the known individual seal expected to remain present at Friday Harbor during
construction. See explanation above.
Analyses and Preliminary Determinations
Negligible Impact Analysis
NMFS has defined ``negligible impact'' in 50 CFR 216.103 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.'' 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
Level B harassment 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 behavioral
harassment, we consider 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
the number and nature of estimated Level A harassment takes, the number
of estimated mortalities, and effects on habitat.
Pile driving activities associated with the marina reconstruction
project, as outlined previously, have the potential to disturb or
displace marine mammals. Specifically, the specified activities may
result in take, in the form of Level B harassment (behavioral
disturbance) only, from underwater sounds generated from pile driving.
Potential takes could occur if individuals of these species are present
in the ensonified zone when pile driving is happening.
No injury, serious injury, or mortality is anticipated given the
methods of construction. Measures designed to minimize the possibility
of injury to marine mammals (e.g., exclusion zones) further reduce any
possibility of injury. Specifically, vibratory hammers are the sole
method of installation, and this activity does not have significant
potential to cause injury to marine mammals due to the relatively low
source levels produced (expected to be less than 180 dB rms) and the
lack of potentially injurious source characteristics. Impact pile
driving produces short, sharp pulses with higher peak levels and much
sharper rise time to reach those peaks than does vibratory driving or
removal. The likelihood that marine mammal detection ability by trained
observers is high under the general environmental conditions expected
for Friday Harbor, in concert with the very small shutdown zones--which
are defined as a precautionary measure only, as expected source levels
are below the relevant injury criteria--further enables the
implementation of shutdowns to avoid any potential for injury.
Effects on individuals that are taken by Level B harassment, on the
basis of reports in the literature as well as monitoring from similar
past projects, will likely be limited to reactions such as increased
swimming speeds, increased surfacing time, or decreased foraging (if
such activity were occurring). Most likely, individuals will simply
move away from the sound source and be temporarily displaced from the
areas of pile driving, although even this reaction has been observed
primarily only in association with impact pile driving. In response to
vibratory driving, harbor seals (which may be somewhat habituated to
human activity along the Friday Harbor waterfront) have been observed
to orient towards and sometimes move towards the sound. Repeated
exposures of individuals to levels of sound that may cause Level B
harassment are unlikely to result in hearing impairment or to
significantly disrupt foraging behavior. Thus, even repeated Level B
harassment of some small subset of an overall stock is unlikely to
result in any significant realized decrease in fitness to those
individuals, and thus would not result in any adverse impact to the
stock as a whole. Level B harassment will be reduced to the level of
least practicable 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 project area while
the activity is occurring.
For pinnipeds, no rookeries are present in the project area, and
there are few haul-outs other than rocks used by harbor seals at the
distant edge of the Level B ZOI for pile installation and opportunistic
haul-outs provided by man-made objects. The project area is not known
to provide foraging habitat of any special importance. The pile driving
activities analyzed here are similar to other nearby construction
activities In Washington inland waters, including recent projects
conducted by WSDOT at the same location (Friday Harbor and Orcas Island
Ferry Terminals), which have taken place with no reported injuries or
mortality to marine mammals, and no known long-term adverse
consequences from behavioral harassment.
In summary, this negligible impact analysis is founded on the
following factors: (1) The possibility of injury, serious injury, or
mortality may reasonably be considered discountable; (2) the
anticipated incidences of Level B harassment consist of, at worst,
temporary modifications in behavior; (3) the absence of any major
rookeries and only a few isolated and opportunistic haul-out areas near
or adjacent to the project site; (4) the absence of any other known
areas or features of special significance for foraging or reproduction
within the project area; and (6) the presumed efficacy of the planned
mitigation measures in reducing the effects of the specified activity
to the level of least practicable impact. In addition, none of the
stocks for which take authorization is proposed are listed
[[Page 43422]]
under the ESA or designated as depleted under the MMPA. All of the
stocks for which take is authorized are thought to be increasing or to
be within OSP size. In combination, we believe that these factors, as
well as the available body of evidence from other similar activities,
including those conducted at the same time of year and in the same
location, demonstrate that the potential effects of the specified
activity will have only short-term effects on individuals. The
specified activity is not expected to impact rates of recruitment or
survival and will therefore not result in population-level impacts.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the proposed monitoring and
mitigation measures, we preliminarily find that the total marine mammal
take from the Port's marina reconstruction activities will have a
negligible impact on the affected marine mammal species or stocks.
Small Numbers Analysis
The numbers of animals authorized to be taken for all species would
be considered small relative to the relevant stocks or populations
(ranging from less than one percent for sea lions and Dall's porpoise
to 4.1 percent for harbor seals) even if each estimated taking occurred
to a new individual--an extremely unlikely scenario. For pinnipeds
occurring in the vicinity of the Friday Harbor waterfront, there will
almost certainly be some overlap in individuals present day-to-day, and
these takes are likely to occur only within some small portion of the
overall regional stock, such as the number of harbor seals that
regularly use nearby haul-out rocks. For migratory species, the segment
of the overall stock to which take would accrue is likely much smaller.
For example, of the estimated 296,500 California sea lions, only
certain adult and subadult males--believed to number approximately
3,000-5,000 by Jeffries et al. (2000)--travel north during the non-
breeding season. That number has almost certainly increased with the
population of California sea lions--the 2000 SAR for California sea
lions reported an estimated population size of 204,000-214,000
animals--but likely remains a relatively small portion of the overall
population.
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 mitigation and monitoring
measures, we preliminarily find that small numbers of marine mammals
will be taken relative to the populations of the affected species or
stocks.
Impact on Availability of Affected Species for Taking for Subsistence
Uses
There are no relevant subsistence uses of marine mammals implicated
by this action. Therefore, we have 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 (ESA)
No marine mammal species listed under the ESA are expected to be
affected by these activities. Therefore, we have determined that a
section 7 consultation under the ESA is not required.
National Environmental Policy Act (NEPA)
We are currently conducting an analysis, pursuant to NEPA of 1969
(42 U.S.C. 4321 et seq.), as implemented by the regulations published
by the Council on Environmental Quality (CEQ; 40 CFR parts 1500-1508),
to determine whether or not this proposed activity may have a
significant effect on the human environment. This analysis will be
completed prior to the issuance or denial of this proposed IHA.
Proposed Authorization
As a result of these preliminary determinations, we propose to
issue an IHA to the Port for conducting the described construction
activities at Friday Harbor, from September 1, 2014 through February
15, 2015, provided the previously mentioned mitigation, monitoring, and
reporting requirements are incorporated. The proposed IHA language is
provided next.
This section contains a draft of the IHA itself. The wording
contained in this section is proposed for inclusion in the IHA (if
issued).
1. This Incidental Harassment Authorization (IHA) is valid from
September 1, 2014 through February 15, 2015.
2. This IHA is valid only for pile driving and removal activities
associated with reconstruction of the Friday Harbor Marina. Any
reference to pile driving in this document is intended to refer to both
pile driving and removal.
3. General Conditions.
(a) A copy of this IHA must be in the possession of the Port, its
designees, and work crew personnel operating under the authority of
this IHA.
(b) The species authorized for taking are the harbor seal (Phoca
vitulina), California sea lion (Zalophus californianus), Steller sea
lion (Eumetopias jubatus), Dall's porpoise (Phocoenoides dalli), and
the harbor porpoise (Phocoena phocoena).
(c) The taking, by Level B harassment only, is limited to the
species listed in condition 3(b). See Table 1 (attached) for numbers of
take authorized.
(d) The taking by injury (Level A harassment), serious injury, or
death of any of the species listed in condition 3(b) of the
Authorization or any taking of any other species of marine mammal is
prohibited and may result in the modification, suspension, or
revocation of this IHA.
(e) The Port shall conduct briefings between construction
supervisors and crews, marine mammal monitoring team, and Port staff
prior to the start of all pile driving activity, and when new personnel
join the work, in order to explain responsibilities, communication
procedures, marine mammal monitoring protocol, and operational
procedures.
4. Mitigation Measures.
The holder of this Authorization is required to implement the
following mitigation measures:
(a) During all pile driving, the Port shall implement a minimum
shutdown zone of 10 m radius around the pile for marine mammals. If a
marine mammal comes within this zone, such operations shall cease. No
marine mammal shall be exposed to sound pressure levels equaling or
exceeding 180/190 dB rms (re 1 [micro]Pa) for cetaceans and pinnipeds,
respectively, in order to prevent unauthorized Level A harassment.
(b) The Port shall similarly avoid direct interaction with marine
mammals during in-water heavy machinery work other than pile driving
that may occur in association with the construction project. If a
marine mammal comes within 10 m of such activity, operations shall
cease and vessels shall reduce speed to the minimum level required to
maintain steerage and safe working conditions, as appropriate.
(c) The Navy shall establish monitoring locations as described in
the Marine Mammal Monitoring Plan (Monitoring Plan; attached). For pile
installation activities, a minimum of one observer shall be assigned to
the active pile driving rig in order to monitor the shutdown zone,
while at least three additional observers shall be positioned for
optimal monitoring of the surrounding waters within the Level B
harassment zone. At least two of these shall be vessel-based. During
pile removal, a minimum of three observers shall be deployed at the
best vantage
[[Page 43423]]
points to observe the shutdown and disturbance zones. The zone to be
monitored is as depicted in Figure 2 of the attached Plan. These
observers shall record all observations of marine mammals, as well as
behavior and potential behavioral reactions of the animals.
(d) Monitoring shall take place from 15 minutes prior to initiation
of pile driving activity through 30 minutes post-completion of pile
driving activity. Pre-activity monitoring shall be conducted for 15
minutes to ensure that the shutdown zone is clear of marine mammals,
and pile driving may commence when observers have declared the shutdown
zone clear of marine mammals. In the event of a delay or shutdown of
activity resulting from marine mammals in the shutdown zone, animals
shall be allowed to remain in the shutdown zone (i.e., must leave of
their own volition) and their behavior shall be monitored and
documented. Monitoring shall occur throughout the time required to
drive a pile. The shutdown zone must be determined to be clear during
periods of good visibility (i.e., the entire shutdown zone and
surrounding waters must be visible to the naked eye).
(e) If a marine mammal approaches or enters the shutdown zone, all
pile driving activities shall be halted. If pile driving is halted or
delayed due to the presence of a marine mammal, the activity may not
commence or resume until either the animal has voluntarily left and
been visually confirmed beyond the shutdown zone or 15 minutes have
passed without re-detection of the animal.
(f) Monitoring shall be conducted by qualified observers, as
described in the Monitoring Plan. Trained observers shall be placed
from the best vantage point(s) practicable to monitor for marine
mammals and implement shutdown or delay procedures when applicable
through communication with the equipment operator.
(g) The Port shall use soft start techniques recommended by NMFS
for vibratory pile driving. The soft start requires contractors to
initiate sound from vibratory hammers for fifteen seconds at reduced
energy followed by a thirty-second waiting period. This procedure is
repeated two additional times. Soft start shall be implemented at the
start of each day's vibratory pile driving and at any time following
cessation of pile driving for a period of 30 minutes or longer.
(h) Pile driving shall only be conducted during daylight hours.
5. Monitoring.
The holder of this Authorization is required to conduct marine
mammal monitoring during pile driving activity. Marine mammal
monitoring and reporting shall be conducted in accordance with the
Monitoring Plan.
(a) The Port shall collect sighting data and behavioral responses
to pile driving for marine mammal species observed in the region of
activity during the period of activity. All observers shall be trained
in marine mammal identification and behaviors, and shall have no other
construction-related tasks while conducting monitoring.
(b) For all marine mammal monitoring, the information shall be
recorded as described in the Monitoring Plan, to include at minimum:
(i) Date and time that monitored activity begins or ends;
(ii) Construction activities occurring during each observation
period;
(iii) Weather parameters (e.g., percent cover, visibility);
(iv) Water conditions (e.g., sea state, tide state);
(v) Species, numbers, and, if possible, sex and age class of marine
mammals;
(vi) Description of any observable marine mammal behavior patterns,
including bearing and direction of travel and distance from pile
driving activity;
(vii) Distance from pile driving activities to marine mammals and
distance from the marine mammals to the observation point;
(viii) Locations of all marine mammal observations; and
(ix) Other human activity in the area.
6. Reporting.
The holder of this Authorization is required to:
(a) Submit a draft report on all marine mammal monitoring conducted
under the IHA within 90 calendar days of the end of the in-water work
period. A final report shall be prepared and submitted within 30 days
following resolution of comments on the draft report from NMFS. This
report must contain the informational elements described under 5(b), at
minimum.
(b) Reporting injured or dead marine mammals:
i. In the unanticipated event that the specified activity clearly
causes the take of a marine mammal in a manner prohibited by this IHA,
such as an injury (Level A harassment), serious injury, or mortality,
Port shall immediately cease the specified activities and report the
incident to the Office of Protected Resources (301-427-8425), NMFS, and
the West Coast Regional Stranding Coordinator (206-526-6550), NMFS. The
report must include the following information:
A. Time and date of the incident;
B. Description of the incident;
C. Environmental conditions (e.g., wind speed and direction,
Beaufort sea state, cloud cover, and visibility);
D. Description of all marine mammal observations in the 24 hours
preceding the incident;
E. Species identification or description of the animal(s) involved;
F. Fate of the animal(s); and
G. Photographs or video footage of the animal(s).
Activities shall not resume until NMFS is able to review the
circumstances of the prohibited take. NMFS will work with Port to
determine what measures are necessary to minimize the likelihood of
further prohibited take and ensure MMPA compliance. Port may not resume
their activities until notified by NMFS.
(i) In the event that Port discovers an injured or dead marine
mammal, and the lead observer determines that the cause of the injury
or death is unknown and the death is relatively recent (e.g., in less
than a moderate state of decomposition), Port shall immediately report
the incident to the Office of Protected Resources, NMFS, and the West
Coast Regional Stranding Coordinator, NMFS.
The report must include the same information identified in 6(b)(i)
of this IHA. Activities may continue while NMFS reviews the
circumstances of the incident. NMFS will work with Port to determine
whether additional mitigation measures or modifications to the
activities are appropriate.
(ii) In the event that Port discovers an injured or dead marine
mammal, and the lead observer determines that the injury or death is
not associated with or related to the activities authorized in the IHA
(e.g., previously wounded animal, carcass with moderate to advanced
decomposition, scavenger damage), Port shall report the incident to the
Office of Protected Resources, NMFS, and the West Coast Regional
Stranding Coordinator, NMFS, within 24 hours of the discovery. Port
shall provide photographs or video footage or other documentation of
the stranded animal sighting to NMFS.
7. This Authorization may be modified, suspended or withdrawn if
the holder fails to abide by the conditions prescribed herein, or if
the authorized taking is having more than a negligible impact on the
species or stock of affected marine mammals.
Request for Public Comments
We request comment on our analysis, the draft authorization, and
any other aspect of this Notice of Proposed IHA for the Port's
construction activities.
[[Page 43424]]
Please include with your comments any supporting data or literature
citations to help inform our final decision on the Port's request for
an MMPA authorization.
Dated: July 21, 2014.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2014-17446 Filed 7-24-14; 8:45 am]
BILLING CODE 3510-22-P