Notice2023-20534
Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to U.S. Coast Guard Construction in Astoria, Oregon
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
September 27, 2023
Issuing agencies
Commerce DepartmentNational Oceanic and Atmospheric Administration
Abstract
NMFS has received a request from the United States Coast Guard (USCG) for authorization to take marine mammals incidental to the East Tongue Point (ETP) construction project in Astoria, Oregon. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to issue an incidental harassment authorization (IHA) to incidentally take marine mammals during the specified activities. NMFS is also requesting comments on a possible one-time, 1-year renewal that could be issued under certain circumstances and if all requirements are met, as described in Request for Public Comments at the end of this notice. NMFS will consider public comments prior to making any final decision on the issuance of the requested MMPA authorization and agency responses will be summarized in the final notice of our decision.
Full Text
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<title>Federal Register, Volume 88 Issue 186 (Wednesday, September 27, 2023)</title>
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[Federal Register Volume 88, Number 186 (Wednesday, September 27, 2023)]
[Notices]
[Pages 66393-66409]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2023-20534]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[RTID 0648-XC044]
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to U.S. Coast Guard Construction in
Astoria, Oregon
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; proposed incidental harassment authorization; request
for comments on proposed authorization and possible renewal.
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SUMMARY: NMFS has received a request from the United States Coast Guard
(USCG) for authorization to take marine mammals incidental to the East
Tongue Point (ETP) construction project in Astoria, Oregon. Pursuant to
the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on
its proposal to issue an incidental harassment authorization (IHA) to
incidentally take marine mammals during the specified activities. NMFS
is also requesting comments on a possible one-time, 1-year renewal that
could be issued under certain circumstances and if all requirements are
met, as described in Request for Public Comments at the end of this
notice. NMFS will consider public comments prior to making any final
decision on the issuance of the requested MMPA authorization and agency
responses will be summarized in the final notice of our decision.
DATES: Comments and information must be received no later than October
27, 2023.
ADDRESSES: Comments should be addressed to Jolie Harrison, Chief,
Permits and Conservation Division, Office of Protected Resources,
National Marine Fisheries Service and should be submitted via email to
<a href="/cdn-cgi/l/email-protection#501904007e3831223c3133383522103e3f31317e373f26"><span class="__cf_email__" data-cfemail="3f766b6f11575e4d535e5c575a4d7f51505e5e11585049">[email protected]</span></a>. Electronic copies of the application and
supporting documents, as well as a list of the references cited in this
document, may be obtained online at: <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities">https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities</a>. In case of problems accessing these documents,
please call the contact listed below.
Instructions: NMFS is not responsible for comments sent by any
other method, to any other address or individual, or received after the
end of the comment period. Comments, including all attachments, must
not exceed a 25-megabyte file size. All comments received are a part of
the public record and will generally be posted online at <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities">https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities</a> without change. All
personal identifying information (e.g., name, address) voluntarily
submitted by the commenter may be publicly accessible. Do not submit
confidential business information or otherwise sensitive or protected
information.
FOR FURTHER INFORMATION CONTACT: Jenna Harlacher, Office of Protected
Resources, NMFS, (301) 427-8401.
SUPPLEMENTARY INFORMATION:
Background
The MMPA prohibits the ``take'' of marine mammals, with certain
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to
allow, upon request, the incidental, but not intentional, taking of
small numbers of marine mammals by U.S. citizens who engage in a
specified activity (other than commercial fishing) within a specified
[[Page 66394]]
geographical region if certain findings are made and either regulations
are proposed or, if the taking is limited to harassment, a notice of a
proposed IHA is provided to the public for review.
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other ``means of effecting the least practicable adverse
impact'' on the affected species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of the species or stocks for
taking for certain subsistence uses (referred to in shorthand as
``mitigation''); and requirements pertaining to the mitigation,
monitoring and reporting of the takings are set forth. The definitions
of all applicable MMPA statutory terms cited above are included in the
relevant sections below.
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must review our proposed action (i.e., the issuance of an IHA)
with respect to potential impacts on the human environment.
This action is consistent with categories of activities identified
in Categorical Exclusion B4 (IHAs with no anticipated serious injury or
mortality) of the Companion Manual for NAO 216-6A, which do not
individually or cumulatively have the potential for significant impacts
on the quality of the human environment and for which we have not
identified any extraordinary circumstances that would preclude this
categorical exclusion. Accordingly, NMFS has preliminarily determined
that the issuance of the proposed IHA qualifies to be categorically
excluded from further NEPA review.
We will review all comments submitted in response to this notice
prior to concluding our NEPA process or making a final decision on the
IHA request.
Summary of Request
On April 22, 2022, NMFS received a request from the USCG for an IHA
to take marine mammals incidental to pile driving activity associated
with the ETP construction in Astoria, Oregon. Following NMFS' review of
the application, we received a revised version of the application on
June 27, 2022. After finalizing construction details, the USCG
submitted another revised version on May 26, 2023, followed by a final
revised version on July 24, 2023, which was deemed adequate and
complete on August 1, 2023. USCG's request is for take of harbor seal,
California sea lion, Steller sea lion and harbor porpoise by Level B
harassment and, for harbor seal and harbor porpoise, Level A
harassment. Neither USCG nor NMFS expect serious injury or mortality to
result from this activity and, therefore, an IHA is appropriate.
Description of Proposed Activity
Overview
The USCG requested an IHA to homeport multiple new Fast Response
Cutters (FRC) to support USCG District 13 at ETP in Astoria, OR (Figure
1). This three-phased project entails both onshore and in-water
construction activities to remove old piles, construct and improve
facilities necessary for the long-term support of the FRC's and USCG
mission. Phase 1 includes pile removal and demolition, dredging and
shoreline rock improvements, phase 2 includes all pile driving and in
water construction, and phase 3 includes all overwater and upland
construction. The USCG completed a Homeport feasibility study in 2015
to determine the best site for FRC and determined ETP was the most
suitable site due to favorable currents and low exposure to wave
action.
This overall project is needed to improve or construct waterside
and landslide facilities that will meet homeporting requirements of the
FRCs. This includes the availability of logistics and support amenities
for personnel, the ability of the new FRC docks/floats to accommodate
the FRCs with all necessary operations on the boat while it is
stationary at the dock, and the ability of the facility to provide for
a long-term USCG presence for the economic life of its assets.
Facilities at ETP are aged, outdated, and will require improvements to
meet homeporting requirements.
Of the stages of this project, the only part that may result in
Level A and Level B harassment, and further analyzed in this notice is
the in-water construction activities associated with impact pile
driving (Phase 2). The USCG proposes installation of 30-inch (in) and
36-in steel pipe piles for their new facilities with an estimated 52
total days of impact pile driving. Pile driving will only occur within
the Oregon Department of Fish and Wildlife (ODFW) approved in-water
working window, however the proposed IHA will have a 1-year period of
effectiveness. Phase 1 which includes dredging, pile removal and
shoreline improvements and phase 3 involving only landside or over-
water improvements, do not result in take based on the noise analysis
and implementation of mitigation measures by the USCG and therefore
will not be discussed further.
Dates and Duration
The ETP project is planned in a 3-phase approach with only phase 2
covered under this IHA. The IHA would be valid from November 1, 2023 to
October 31, 2024; however, pile driving would only occur in the ODFW
in-water work window from November 1, 2023 to February 29, 2024.
Specific Geographic Region
The project location is on the east side of the Tongue Point
peninsula protruding into the Columbia River at approximately river
mile 18. It lies in the northern portion of an industrial concrete pier
area, formerly associated with a World War II-era U.S. Navy
installation, just north of Highway 30 approximately 3 miles east of
Astoria (Figure 1). The proposed project area is located within the
Tongue Point Department of Labor Jobs Corps Center, which falls inside
the urban growth boundary for Astoria. Various industrial and
commercial uses, mostly for the marine industry, occur on the southern
portion of the ETP site. To the north-northeast of the developed
industrial area, the forested Tongue Point peninsula remains a
designated natural area.
The project area is bound by the main stem of the Columbia River to
the north and west and by Cathlamet Bay to the south and east. Mott
Island is located approximately 0.5 miles east of the project area and
Mill Creek flows into the Columbia River immediately south of the
capped landfill. Further south and east up the John Day channel, Lois
Island lies across from the John Day River mouth and a protected deep-
water anchorage area is found. Moss and Lois Islands are part of the
Lewis and Clark National Wildlife Refuge, which encompasses all islands
approximately 27 miles upstream from the mouth of the Columbia River
(USFWS 2020).
BILLING CODE 3510-22-P
[[Page 66395]]
[GRAPHIC] [TIFF OMITTED] TN27SE23.006
BILLING CODE 3510-22-C
Detailed Description of the Specified Activity
Equipment and most materials needed to perform pier demolition and
disposal, dredging, pile driving, pier, and floating dock construction
will be mobilized via barges. It is anticipated that multiple barges
may be present in the project or project staging areas at any time. The
selected design-build contractor will mobilize equipment and materials
based on the project phasing and task schedule to be determined once
the project has been contracted. The overall project includes landslide
improvements, waterside improvements, in-water construction, over-water
construction, and upland construction. However, as previously stated
this IHA only covers in-water construction associated with pile
installation activities that could result in take of marine mammals.
Piles will be installed during the in-water work window from
November 1, 2023, through February 29, 2024, using impact hammers, per
Table 1-1 and Table 1-2 in USCG's application. USCG estimates up to
three piles will be driven each 8 hour workday, and the actual driving
time for each pile could be as high as approximately 30 minutes. An
estimated 52 total days of pile driving (not all consecutive) will
occur during the in-water work window from November through February.
Impact pile driving associated with the project is the only
activity that could result in incidental take of marine mammals.
Underwater noise generated during pile driving is dependent upon the
impact energy produced by the pile driving hammer, the type and size of
pile, water depth, and the substrate into
[[Page 66396]]
which the pile is being driven. Modeled pile driving scenarios
accounted for the energy needed to drive the piles and utilized the two
largest diameter pile sizes for the model as determined from
engineering plans. A water depth of three meters was used, which is
representative of the project area depths (Table 1).
Table 1--Proposed Pile Driving
----------------------------------------------------------------------------------------------------------------
Estimated
Pile size and type Method Maximum piles Activity duration days of
per day work
----------------------------------------------------------------------------------------------------------------
36-inch steel pipe................ impact install...... 3 40-45 blows per minute 52
for 9 minutes.
30-inch steel pipe................ impact install...... 3 40-45 blows per minute ...........
for 9 minutes.
----------------------------------------------------------------------------------------------------------------
Proposed mitigation, monitoring, and reporting measures are
described in detail later in this document (please see Proposed
Mitigation and Proposed Monitoring and Reporting).
Description of Marine Mammals in the Area of Specified Activities
Sections 3 and 4 of the application summarize available information
regarding status and trends, distribution and habitat preferences, and
behavior and life history of the potentially affected species. NMFS
fully considered all of this information, and we refer the reader to
these descriptions, instead of reprinting the information. Additional
information regarding population trends and threats may be found in
NMFS' Stock Assessment Reports (SARs; <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments</a>) and
more general information about these species (e.g., physical and
behavioral descriptions) may be found on NMFS' website (<a href="https://www.fisheries.noaa.gov/find-species">https://www.fisheries.noaa.gov/find-species</a>).
Table 2 lists all species or stocks for which take is expected and
proposed to be authorized for this activity, and summarizes information
related to the population or stock, including regulatory status under
the MMPA and Endangered Species Act (ESA) and potential biological
removal (PBR), where known. PBR is defined by the MMPA as the maximum
number of animals, not including natural mortalities, that may be
removed from a marine mammal stock while allowing that stock to reach
or maintain its optimum sustainable population (as described in NMFS'
SARs). While no serious injury or mortality is anticipated or proposed
to be authorized here, PBR and annual serious injury and mortality from
anthropogenic sources are included here as gross indicators of the
status of the species or stocks and other threats.
Marine mammal abundance estimates presented in this document
represent the total number of individuals that make up a given stock or
the total number estimated within a particular study or survey area.
NMFS' stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprises that stock. For some species, this geographic area may extend
beyond U.S. waters. All managed stocks in this region are assessed in
NMFS' U.S. Pacific and Alaska SARs. All values presented in Table 2 are
the most recent available at the time of publication and are available
online at: <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments</a>.
Table 2--Species Likely Impacted by the Specified Activities
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ESA/ MMPA status; Stock abundance (CV,
Common name Scientific name Stock strategic (Y/N) Nmin, most recent PBR Annual M/
\1\ abundance survey) \2\ SI \3\
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Odontoceti (toothed whales, dolphins, and porpoises)
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Family Phocoenidae (porpoises):
Harbor Porpoise................. Phocoena phocoena...... Northern Oregon/ -,-,N 21,487 (0.44, 15,123, 151 >=3.0
Washington Coast. 2011).
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Order Carnivora--Superfamily Pinnipedia
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Family Otariidae (eared seals and
sea lions):
California Sea Lion............. Zalophus californianus. US..................... -,-,N 257,606 (N/A, 233,515, 14,011 >321
2014).
Steller Sea Lion................ Eumetopias jubatus..... Eastern................ -,-,N 43,201 (N/A, 43,201, 2,592 112
2017).
Family Phocidae (earless seals)
Harbor Seal..................... Phoca vitulina......... Oregon/Washington Coast -,-,N UNK................... UND 10.6
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\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: https:// <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports/">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports/</a>. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
associated with estimated mortality due to commercial fisheries is presented in some cases.
As indicated above, all four species in Table 2 temporally and
spatially co-occur with the activity to the degree that take is
reasonably likely to occur. While killer whales (Orcinus orca),
humpback whales (Megaptera novaeangliae), and
[[Page 66397]]
gray whales (Eschrichtius robustus) have been sighted off the Oregon
coast, the USCG's project is located 23 km into the mouth of the
Columbia River. Therefor the temporal and/or spatial occurrence of
these species is such that take is not expected to occur, and they are
not discussed further beyond the explanation provided here and in the
USCG's application.
Marine Mammal Hearing
Hearing is the most important sensory modality for marine mammals
underwater, and exposure to anthropogenic sound can have deleterious
effects. To appropriately assess the potential effects of exposure to
sound, it is necessary to understand the frequency ranges marine
mammals are able to hear. Not all marine mammal species have equal
hearing capabilities (e.g., Richardson et al., 1995; Wartzok and
Ketten, 1999; Au and Hastings, 2008). To reflect this, Southall et al.
(2007, 2019) recommended that marine mammals be divided into hearing
groups based on directly measured (behavioral or auditory evoked
potential techniques) or estimated hearing ranges (behavioral response
data, anatomical modeling, etc.). Note that no direct measurements of
hearing ability have been successfully completed for mysticetes (i.e.,
low-frequency cetaceans). Subsequently, NMFS (2018) described
generalized hearing ranges for these marine mammal hearing groups.
Generalized hearing ranges were chosen based on the approximately 65
decibel (dB) threshold from the normalized composite audiograms, with
the exception for lower limits for low-frequency cetaceans where the
lower bound was deemed to be biologically implausible and the lower
bound from Southall et al. (2007) retained. Marine mammal hearing
groups and their associated hearing ranges are provided in Table 3.
Table 3--Marine Mammal Hearing Groups
[NMFS, 2018]
------------------------------------------------------------------------
Hearing group Generalized hearing range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen 7 Hz to 35 kHz.
whales).
Mid-frequency (MF) cetaceans 150 Hz to 160 kHz.
(dolphins, toothed whales, beaked
whales, bottlenose whales).
High-frequency (HF) cetaceans (true 275 Hz to 160 kHz.
porpoises, Kogia, river dolphins,
Cephalorhynchid, Lagenorhynchus
cruciger & L. australis).
Phocid pinnipeds (PW) (underwater) 50 Hz to 86 kHz.
(true seals).
Otariid pinnipeds (OW) (underwater) 60 Hz to 39 kHz.
(sea lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
composite (i.e., all species within the group), where individual
species' hearing ranges are typically not as broad. Generalized
hearing range chosen based on ~65 dB threshold from normalized
composite audiogram, with the exception for lower limits for LF
cetaceans (Southall et al. 2007) and PW pinniped (approximation).
The pinniped functional hearing group was modified from Southall et
al. (2007) on the basis of data indicating that phocid species have
consistently demonstrated an extended frequency range of hearing
compared to otariids, especially in the higher frequency range
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt,
2013).
For more detail concerning these groups and associated frequency
ranges, please see NMFS (2018) for a review of available information.
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
This section provides a discussion of the ways in which components
of the specified activity may impact marine mammals and their habitat.
The Estimated Take of Marine Mammals section later in this document
includes a quantitative analysis of the number of individuals that are
expected to be taken by this activity. The Negligible Impact Analysis
and Determination section considers the content of this section, the
Estimated Take of Marine Mammals section, and the Proposed Mitigation
section, to draw conclusions regarding the likely impacts of these
activities on the reproductive success or survivorship of individuals
and whether those impacts are reasonably expected to, or reasonably
likely to, adversely affect the species or stock through effects on
annual rates of recruitment or survival.
Acoustic effects on marine mammals during the specified activity
can occur from impact pile driving. The effects of underwater noise
from USCG's proposed activities have the potential to result in Level A
or Level B harassment of marine mammals in the action area.
Description of Sound Source
The marine soundscape is comprised of both ambient and
anthropogenic sounds. Ambient sound is defined as the all-encompassing
sound in a given place and is usually a composite of sound from many
sources both near and far. The sound level of an area is defined by the
total acoustical energy being generated by known and unknown sources.
These sources may include physical (e.g., waves, wind, precipitation,
earthquakes, ice, atmospheric sound), biological (e.g., sounds produced
by marine mammals, fish, and invertebrates), and anthropogenic sound
(e.g., vessels, dredging, aircraft, construction).
The sum of the various natural and anthropogenic sound sources at
any given location and time--which comprise ``ambient'' or
``background'' sound--depends not only on the source levels (as
determined by current weather conditions and levels of biological and
shipping activity) but also on the ability of sound to propagate
through the environment. In turn, sound propagation is dependent on the
spatially and temporally varying properties of the water column and sea
floor, and is frequency-dependent. As a result of the dependence on a
large number of varying factors, ambient sound levels can be expected
to vary widely over both coarse and fine spatial and temporal scales.
Sound levels at a given frequency and location can vary by 10-20 dB
from day to day (Richardson et al., 1995). The result is that,
depending on the source type and its intensity, sound from the
specified activity may be a negligible addition to the local
environment or could form a distinctive signal that may affect marine
mammals.
In-water construction activities associated with the project would
include vibratory pile removal, and impact and vibratory pile driving.
The sounds produced by these activities fall into one of two general
sound types: impulsive and non-impulsive. Impulsive sounds (e.g.,
explosions, gunshots, sonic booms, impact pile driving) are typically
transient, brief (less than 1 second), broadband, and consist of high
peak sound pressure with rapid rise time and rapid decay
[[Page 66398]]
(ANSI, 1986; NIOSH, 1998; ANSI, 2005; NMFS, 2018a). Non-impulsive
sounds (e.g., aircraft, machinery operations such as drilling or
dredging, vibratory pile driving, and active sonar systems) can be
broadband, narrowband or tonal, brief or prolonged (continuous or
intermittent), and typically do not have the high peak sound pressure
with raid rise/decay time that impulsive sounds do (ANSI, 1995; NIOSH,
1998; NMFS, 2018a). The distinction between these two sound types is
important because they have differing potential to cause physical
effects, particularly with regard to hearing (e.g., Ward 1997 in
Southall et al., 2007).
USCG propose to use impact pile driving to install new steel pipe
piles associated with the ETP project. Impact hammers operate by
repeatedly dropping a heavy piston onto a pile to drive the pile into
the substrate. Sound generated by impact hammers is characterized by
rapid rise times and high peak levels, a potentially injurious
combination (Hastings and Popper, 2005). Peak sound pressure levels
(SPLs) may be 180 dB or greater, but are generally 10 to 20 dB lower
than SPLs generated during impact pile driving of the same-sized pile
(Oestman et al., 2009). Rise time is slower, reducing the probability
and severity of injury, and sound energy is distributed over a greater
amount of time (Nedwell and Edwards, 2002; Carlson et al., 2005).
The likely or possible impacts of USCG's proposed activity on
marine mammals could involve both non-acoustic and acoustic stressors.
Potential non-acoustic stressors could result from the physical
presence of equipment and personnel; however, any impacts to marine
mammals are expected to be primarily acoustic in nature. Acoustic
stressors include effects of heavy equipment operation during pile
driving.
Acoustic Impacts
The introduction of anthropogenic noise into the aquatic
environment from pile driving is the primary means by which marine
mammals may be harassed from the USCG's specified activity. In general,
animals exposed to natural or anthropogenic sound may experience
physical and psychological effects, ranging in magnitude from none to
severe (Southall et al., 2007). In general, exposure to pile driving
noise has the potential to result in auditory threshold shifts and
behavioral reactions (e.g., avoidance, temporary cessation of foraging
and vocalizing, changes in dive behavior). Exposure to anthropogenic
noise can also lead to non-observable physiological responses, such as
an increase in stress hormones. Additional noise in a marine mammal's
habitat can mask acoustic cues used by marine mammals to carry out
daily functions, such as communication and predator and prey detection.
The effects of pile driving noise on marine mammals are dependent on
several factors, including, but not limited to, sound type (e.g.,
impulsive vs. non-impulsive), the species, age and sex class (e.g.,
adult male vs. mom with calf), duration of exposure, the distance
between the pile and the animal, received levels, behavior at time of
exposure, and previous history with exposure (Wartzok et al., 2004;
Southall et al., 2007). Here we discuss physical auditory effects
(threshold shifts) followed by behavioral effects and potential impacts
on habitat.
NMFS defines a noise-induced threshold shift (TS) as a change,
usually an increase, in the threshold of audibility at a specified
frequency or portion of an individual's hearing range above a
previously established reference level (NMFS, 2018). The amount of TS
is customarily expressed in dB. TS can be permanent or temporary. As
described in NMFS (2018), there are numerous factors to consider when
examining the consequence of TS, including, but not limited to, the
signal temporal pattern (e.g., impulsive or non-impulsive), likelihood
an individual would be exposed for a long enough duration or to a high
enough level to induce a TS, the magnitude of the TS, time to recovery
(seconds to minutes or hours to days), the frequency range of the
exposure (i.e., spectral content), the hearing and vocalization
frequency range of the exposed species relative to the signal's
frequency spectrum (i.e., how an animal uses sound within the frequency
band of the signal; (e.g., Kastelein et al., 2014), and the overlap
between the animal and the source (e.g., spatial, temporal, and
spectral).
Permanent Threshold Shift (PTS)--NMFS defines PTS as a permanent,
irreversible increase in the threshold of audibility at a specified
frequency or portion of an individual's hearing range above a
previously established reference level (NMFS, 2018). Available data
from humans and other terrestrial mammals indicate that a 40 dB
threshold shift approximates PTS onset (see Ward et al., 1958, 1959;
Ward, 1960; Kryter et al., 1966; Miller, 1974; Ahroon et al., 1996;
Henderson et al., 2008). PTS levels for marine mammals are estimates,
as with the exception of a single study unintentionally inducing PTS in
a harbor seal (Kastak et al., 2008), there are no empirical data
measuring PTS in marine mammals largely due to the fact that, for
various ethical reasons, experiments involving anthropogenic noise
exposure at levels inducing PTS are not typically pursued or authorized
(NMFS, 2018).
Temporary Threshold Shift (TTS)--TTS is a temporary, reversible
increase in the threshold of audibility at a specified frequency or
portion of an individual's hearing range above a previously established
reference level (NMFS, 2018). Based on data from cetacean TTS
measurements (see Southall et al., 2007), a TTS of 6 dB is considered
the minimum threshold shift clearly larger than any day-to-day or
session-to-session variation in a subject's normal hearing ability
(Schlundt et al., 2000; Finneran et al., 2000, 2002). As described in
Finneran (2015), marine mammal studies have shown the amount of TTS
increases with cumulative sound exposure level (SELcum) in an
accelerating fashion: At low exposures with lower SELcum, the amount of
TTS is typically small and the growth curves have shallow slopes. At
exposures with higher SELcum, the growth curves become steeper and
approach linear relationships with the noise SEL.
Depending on the degree (elevation of threshold in dB), duration
(i.e., recovery time), and frequency range of TTS, and the context in
which it is experienced, TTS can have effects on marine mammals ranging
from discountable to serious (similar to those discussed in Masking,
below). For example, a marine mammal may be able to readily compensate
for a brief, relatively small amount of TTS in a non-critical frequency
range that takes place during a time when the animal is traveling
through the open ocean, where ambient noise is lower and there are not
as many competing sounds present. Alternatively, a larger amount and
longer duration of TTS sustained during a time when communication is
critical for successful mother/calf interactions could have more
serious impacts. We note that reduced hearing sensitivity as a simple
function of aging has been observed in marine mammals, as well as
humans and other taxa (Southall et al., 2007), so we can infer that
strategies exist for coping with this condition to some degree, though
likely not without cost.
Many studies have examined noise-induced hearing loss in marine
mammals (see Finneran (2015) and Southall et al. (2019) for summaries).
For cetaceans, published data on the onset of TTS are limited to the
captive bottlenose dolphin (Tursiops truncatus), beluga whale
(Delphinapterus leucas), harbor porpoise, and Yangtze finless
[[Page 66399]]
porpoise (Neophocoena asiaeorientalis), and for pinnipeds in water,
measurements of TTS are limited to harbor seals, elephant seals
(Mirounga angustirostris), and California sea lions. These studies
examine hearing thresholds measured in marine mammals before and after
exposure to intense sounds. The difference between the pre-exposure and
post-exposure thresholds can be used to determine the amount of
threshold shift at various post-exposure times. The amount and onset of
TTS depends on the exposure frequency. Sounds at low frequencies, well
below the region of best sensitivity, are less hazardous than those at
higher frequencies, near the region of best sensitivity (Finneran and
Schlundt, 2013). At low frequencies, onset-TTS exposure levels are
higher compared to those in the region of best sensitivity (i.e., a low
frequency noise would need to be louder to cause TTS onset when TTS
exposure level is higher), as shown for harbor porpoises and harbor
seals (Kastelein et al., 2019a, 2019b, 2020a, 2020b). In addition, TTS
can accumulate across multiple exposures, but the resulting TTS will be
less than the TTS from a single, continuous exposure with the same SEL
(Finneran et al., 2010; Kastelein et al., 2014; Kastelein et al.,
2015a; Mooney et al., 2009). This means that TTS predictions based on
the total, cumulative SEL will overestimate the amount of TTS from
intermittent exposures, such as sonars and impulsive sources.
Nachtigall et al. (2018) and Finneran (2018) describe the measurements
of hearing sensitivity of multiple odontocete species (bottlenose
dolphin, harbor porpoise, beluga, and false killer whale (Pseudorca
crassidens)) when a relatively loud sound was preceded by a warning
sound. These captive animals were shown to reduce hearing sensitivity
when warned of an impending intense sound. Based on these experimental
observations of captive animals, the authors suggest that wild animals
may dampen their hearing during prolonged exposures or if conditioned
to anticipate intense sounds. Another study showed that echolocating
animals (including odontocetes) might have anatomical specializations
that might allow for conditioned hearing reduction and filtering of
low-frequency ambient noise, including increased stiffness and control
of middle ear structures and placement of inner ear structures (Ketten
et al., 2021). Data available on noise-induced hearing loss for
mysticetes are currently lacking (NMFS, 2018).
Behavioral Harassment--Exposure to noise from pile driving and
removal also has the potential to behaviorally disturb marine mammals.
Available studies show wide variation in response to underwater sound;
therefore, it is difficult to predict specifically how any given sound
in a particular instance might affect marine mammals perceiving the
signal. If a marine mammal does react briefly to an underwater sound by
changing its behavior or moving a small distance, the impacts of the
change are unlikely to be significant to the individual, let alone the
stock or population. However, if a sound source displaces marine
mammals from an important feeding or breeding area for a prolonged
period, impacts on individuals and populations could be significant
(e.g., Lusseau and Bejder, 2007; Weilgart, 2007; NRC, 2005).
Disturbance may result in changing durations of surfacing and
dives, number of blows per surfacing, or moving direction and/or speed;
reduced/increased vocal activities; changing/cessation of certain
behavioral activities (such as socializing or feeding); visible startle
response or aggressive behavior (such as tail/fluke slapping or jaw
clapping); and, avoidance of areas where sound sources are located.
Pinnipeds may increase their haul out time, possibly to avoid in-water
disturbance (Thorson and Reyff, 2006). Behavioral responses to sound
are highly variable and context-specific and any reactions depend on
numerous intrinsic and extrinsic factors (e.g., species, state of
maturity, experience, current activity, reproductive state, auditory
sensitivity, time of day), as well as the interplay between factors
(e.g., Richardson et al., 1995; Wartzok et al., 2003; Southall et al.,
2007; Weilgart, 2007; Archer et al., 2010). Behavioral reactions can
vary not only among individuals but also within an individual,
depending on previous experience with a sound source, context, and
numerous other factors (Ellison et al., 2012), and can vary depending
on characteristics associated with the sound source (e.g., whether it
is moving or stationary, number of sources, distance from the source).
In general, pinnipeds seem more tolerant of, or at least habituate more
quickly to, potentially disturbing underwater sound than do cetaceans,
and generally seem to be less responsive to exposure to industrial
sound than most cetaceans. Please see Appendices B-C of Southall et
al., (2007) for a review of studies involving marine mammal behavioral
responses to sound.
Disruption of feeding behavior can be difficult to correlate with
anthropogenic sound exposure, so it is usually inferred by observed
displacement from known foraging areas, the appearance of secondary
indicators (e.g., bubble nets or sediment plumes), or changes in dive
behavior. As for other types of behavioral response, the frequency,
duration, and temporal pattern of signal presentation, as well as
differences in species sensitivity, are likely contributing factors to
differences in response in any given circumstance (e.g., Croll et al.,
2001; Nowacek et al., 2004; Madsen et al., 2006; Yazvenko et al.,
2007). A determination of whether foraging disruptions incur fitness
consequences would require information on or estimates of the energetic
requirements of the affected individuals and the relationship between
prey availability, foraging effort and success, and the life history
stage of the animal.
Stress responses--An animal's perception of a threat may be
sufficient to trigger stress responses consisting of some combination
of behavioral responses, autonomic nervous system responses,
neuroendocrine responses, or immune responses (e.g., Seyle, 1950;
Moberg, 2000). In many cases, an animal's first and sometimes most
economical (in terms of energetic costs) response is behavioral
avoidance of the potential stressor. Autonomic nervous system responses
to stress typically involve changes in heart rate, blood pressure, and
gastrointestinal activity. These responses have a relatively short
duration and may or may not have a significant long-term effect on an
animal's fitness.
Neuroendocrine stress responses often involve the hypothalamus-
pituitary-adrenal system. Virtually all neuroendocrine functions that
are affected by stress--including immune competence, reproduction,
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been
implicated in failed reproduction, altered metabolism, reduced immune
competence, and behavioral disturbance (e.g., Moberg, 1987; Blecha,
2000). Increases in the circulation of glucocorticoids are also equated
with stress (Romano et al., 2004).
The primary distinction between stress (which is adaptive and does
not normally place an animal at risk) and ``distress'' is the cost of
the response. During a stress response, an animal uses glycogen stores
that can be quickly replenished once the stress is alleviated. In such
circumstances, the cost of the stress response would not pose serious
[[Page 66400]]
fitness consequences. However, when an animal does not have sufficient
energy reserves to satisfy the energetic costs of a stress response,
energy resources must be diverted from other functions. This state of
distress will last until the animal replenishes its energetic reserves
sufficient to restore normal function.
Relationships between these physiological mechanisms, animal
behavior, and the costs of stress responses are well studied through
controlled experiments and for both laboratory and free-ranging animals
(e.g., Holberton et al., 1996; Hood et al., 1998; Jessop et al., 2003;
Krausman et al., 2004; Lankford et al., 2005). Stress responses due to
exposure to anthropogenic sounds or other stressors and their effects
on marine mammals have also been reviewed (Fair and Becker, 2000;
Romano et al., 2002b) and, more rarely, studied in wild populations
(e.g., Romano et al., 2002a). For example, Rolland et al., (2012) found
that noise reduction from reduced ship traffic in the Bay of Fundy was
associated with decreased stress in North Atlantic right whales. These
and other studies lead to a reasonable expectation that some marine
mammals will experience physiological stress responses upon exposure to
acoustic stressors and that it is possible that some of these would be
classified as ``distress.'' In addition, any animal experiencing TTS
would likely also experience stress responses (NRC, 2003), however
distress is an unlikely result of this project based on observations of
marine mammals during previous, similar projects in the area.
Masking--Sound can disrupt behavior through masking, or interfering
with, an animal's ability to detect, recognize, or discriminate between
acoustic signals of interest (e.g., those used for intraspecific
communication and social interactions, prey detection, predator
avoidance, navigation) (Richardson et al., 1995). Masking occurs when
the receipt of a sound is interfered with by another coincident sound
at similar frequencies and at similar or higher intensity, and may
occur whether the sound is natural (e.g., snapping shrimp, wind, waves,
precipitation) or anthropogenic (e.g., pile driving, shipping, sonar,
seismic exploration) in origin. The ability of a noise source to mask
biologically important sounds depends on the characteristics of both
the noise source and the signal of interest (e.g., signal-to-noise
ratio, temporal variability, direction), in relation to each other and
to an animal's hearing abilities (e.g., sensitivity, frequency range,
critical ratios, frequency discrimination, directional discrimination,
age or TTS hearing loss), and existing ambient noise and propagation
conditions. Masking of natural sounds can result when human activities
produce high levels of background sound at frequencies important to
marine mammals. Conversely, if the background level of underwater sound
is high (e.g., on a day with strong wind and high waves), an
anthropogenic sound source would not be detectable as far away as would
be possible under quieter conditions and would itself be masked.
Airborne Acoustic Effects--Although pinnipeds are known to haul out
regularly near Astoria, we believe that incidents of take resulting
solely from airborne sound are unlikely due to the sheltered proximity
between the proposed project area and these haul-out sites which are at
least 3 miles (4.8 kilometers) away and not in the acoustic zones that
could be directly affect by noise disturbance. There is a possibility
that an animal could surface in-water, but with head out, within the
area in which airborne sound exceeds relevant thresholds and thereby be
exposed to levels of airborne sound that we associate with harassment,
but any such occurrence would likely be accounted for in our estimation
of incidental take from underwater sound. Therefore, authorization of
incidental take resulting from airborne sound for pinnipeds is not
warranted, and airborne sound is not discussed further here. Cetaceans
are not expected to be exposed to airborne sounds that would result in
harassment as defined under the MMPA.
Marine Mammal Habitat Effects
The USCG's construction activities could have localized, temporary
impacts on marine mammal habitat and their prey by increasing in-water
sound pressure levels and slightly decreasing water quality. However,
the proposed location is not heavily used by marine mammals and is in
close proximity to a heavily trafficked industrial area. Construction
activities are of short duration and would likely have temporary
impacts on marine mammal habitat through increases in underwater and
airborne sound. Increased noise levels may affect acoustic habitat (see
Masking discussion above) and adversely affect marine mammal prey in
the vicinity of the project area (see discussion below). During impact
and vibratory pile driving, elevated levels of underwater noise would
ensonify the project area where both fish and mammals occur and could
affect foraging success.
Temporary and localized increase in turbidity near the seafloor
would occur in the immediate area surrounding the area where piles are
installed. In general, turbidity associated with pile installation is
localized to about a 25 feet (ft) (7.6 meter) radius around the pile
(Everitt et al., 1980). The sediments of the project site will settle
out rapidly when disturbed. Cetaceans are not expected to be close
enough to the pile driving areas to experience effects of turbidity,
and any pinnipeds could avoid localized areas of turbidity. Local
strong currents are anticipated to disburse any additional suspended
sediments produced by project activities at moderate to rapid rates
depending on tidal stage. Therefore, we expect the impact from
increased turbidity levels to be discountable to marine mammals and do
not discuss it further.
In-Water Construction Effects on Potential Foraging Habitat
The proposed activities would result in a minor loss of habitat and
potentially change underwater features for fish, but these changes are
insignificant and limited to the area of redevelopment. The total
seafloor area likely impacted by the project is relatively small
compared to the available habitat in the Columbia River Gorge and on
the Pacific Coast and does not include any Biologically Important Areas
(BIA) or other habitat of known importance. The area is highly
influenced by anthropogenic activities. Additionally, the total
seafloor area affected by pile installation and removal is a small area
compared to the vast foraging area available to marine mammals in the
area. At best, the impact area provides marginal foraging habitat for
marine mammals and fishes. Furthermore, pile driving at the project
site would not obstruct movements or migration of marine mammals.
Avoidance by potential prey (i.e., fish) of the immediate area due
to the temporary loss of this foraging habitat is also possible. The
duration of fish avoidance of this area after pile driving stops is
unknown, but a rapid return to normal recruitment, distribution and
behavior is anticipated. Any behavioral avoidance by fish of the
disturbed area would still leave significantly large areas of fish and
marine mammal foraging habitat in the nearby vicinity.
Effects on Potential Prey
Sound may affect marine mammals through impacts on the abundance,
behavior, or distribution of prey species (e.g., crustaceans,
cephalopods, fish, zooplankton, etc.). Marine mammal prey varies by
species, season, and location.
[[Page 66401]]
However, impacts to prey will be limited to the construction window of
November 1, 2023 through February 29, 2024 to reduce impacts to fish
species in the area. Here, we describe studies regarding the effects of
noise on known marine mammal prey.
Fish utilize the soundscape and components of sound in their
environment to perform important functions such as foraging, predator
avoidance, mating, and spawning (e.g., Zelick and Mann, 1999; Fay,
2009). Depending on their hearing anatomy and peripheral sensory
structures, which vary among species, fishes hear sounds using pressure
and particle motion sensitivity capabilities and detect the motion of
surrounding water (Fay et al., 2008). The potential effects of noise on
fishes depends on the overlapping frequency range, distance from the
sound source, water depth of exposure, and species-specific hearing
sensitivity, anatomy, and physiology. Key impacts to fishes may include
behavioral responses, hearing damage, barotrauma (pressure-related
injuries), and mortality.
Fish react to sounds that are especially strong and/or intermittent
low-frequency sounds, and behavioral responses, such as flight or
avoidance, are the most likely effects. Short duration, sharp sounds
can cause overt or subtle changes in fish behavior and local
distribution. The reaction of fish to noise depends on the
physiological state of the fish, past exposures, motivation (e.g.,
feeding, spawning, migration), and other environmental factors.
Hastings and Popper (2005) identified several studies that suggest fish
may relocate to avoid certain areas of sound energy. Additional studies
have documented effects of pile driving on fish, although several are
based on studies in support of large, multiyear bridge construction
projects (e.g., Scholik and Yan, 2001, 2002; Popper and Hastings,
2009). Several studies have demonstrated that impulse sounds might
affect the distribution and behavior of some fishes, potentially
impacting foraging opportunities or increasing energetic costs (e.g.,
Fewtrell and McCauley, 2012; Pearson et al., 1992; Skalski et al.,
1992; Santulli et al., 1999; Paxton et al., 2017). However, some
studies have shown no or slight reaction to impulse sounds (e.g., Pena
et al., 2013; Wardle et al., 2001; Jorgenson and Gyselman, 2009; Popper
et al., 2015).
SPLs of sufficient strength have been known to cause injury to fish
and fish mortality. However, in most fish species, hair cells in the
ear continuously regenerate and loss of auditory function likely is
restored when damaged cells are replaced with new cells. Halvorsen et
al., (2012a) showed that a TTS of 4-6 dB was recoverable within 24
hours for one species. Impacts would be most severe when the individual
fish is close to the source and when the duration of exposure is long.
Injury caused by barotrauma can range from slight to severe and can
cause death, and is most likely for fish with swim bladders. Barotrauma
injuries have been documented during controlled exposure to impact pile
driving (Halvorsen et al., 2012b; Casper et al., 2013).
The most likely impact to fish from pile driving activities at the
project areas would be temporary behavioral avoidance of the area. The
duration of fish avoidance of an area after pile driving stops is
unknown, but a rapid return to normal recruitment, distribution and
behavior is anticipated.
Construction activities, in the form of increased turbidity, have
the potential to adversely affect forage fish in the project area.
Forage fish form a significant prey base for many marine mammal species
that occur in the project area. Increased turbidity is expected to
occur in the immediate vicinity (on the order of 10 ft (3 meters (m))
or less) of construction activities. However, suspended sediments and
particulates are expected to dissipate quickly within a single tidal
cycle. Given the limited area affected and high tidal dilution rates,
any effects on forage fish are expected to be minor or negligible.
Finally, exposure to turbid waters from construction activities is not
expected to be different from the current exposure; fish and marine
mammals in the Columbia River are routinely exposed to substantial
levels of suspended sediment from natural and anthropogenic sources.
In summary, given the short-term and limited duration of sound
associated with pile driving events and the relatively small areas
being affected, pile driving activities associated with the proposed
action are not likely to have a permanent adverse effect on any fish
habitat, or populations of fish species. Any behavioral avoidance by
fish of the disturbed area would be temporary and would still leave
significantly large areas of fish and marine mammal foraging habitat in
the nearby vicinity. Additionally, all in-water work will occur during
the winter, when marine resident fish species are only present in
limited numbers. Thus, we conclude that impacts of the specified
activity are not likely to have more than short-term adverse effects on
any prey habitat or populations of prey species. Further, any impacts
to marine mammal habitat are not expected to result in significant or
long-term consequences for individual marine mammals, or to contribute
to adverse impacts on their populations.
Estimated Take of Marine Mammals
This section provides an estimate of the number of incidental takes
proposed for authorization through this IHA, which will inform both
NMFS' consideration of ``small numbers,'' and the negligible impact
determinations.
Harassment is the only type of take expected to result from these
activities. Except with respect to certain activities not pertinent
here, section 3(18) of the MMPA defines ``harassment'' as any act of
pursuit, torment, or annoyance, which (i) has the potential to injure a
marine mammal or marine mammal stock in the wild (Level A harassment);
or (ii) has the potential to disturb a marine mammal or marine mammal
stock in the wild by causing disruption of behavioral patterns,
including, but not limited to, migration, breathing, nursing, breeding,
feeding, or sheltering (Level B harassment).
Authorized takes would primarily be by Level B harassment, as use
of the acoustic sources (i.e., impact pile driving) has the potential
to result in disruption of behavioral patterns for individual marine
mammals. There is also some potential for auditory injury (Level A
harassment) to result. The proposed mitigation and monitoring measures
are expected to minimize the severity of the taking to the extent
practicable. As described previously, no serious injury or mortality is
anticipated or proposed to be authorized for this activity. Below we
describe how the proposed take numbers are estimated.
For acoustic impacts, generally speaking, we estimate take by
considering: (1) acoustic thresholds above which NMFS believes the best
available science indicates marine mammals will be behaviorally
harassed or incur some degree of permanent hearing impairment; (2) the
area or volume of water that will be ensonified above these levels in a
day; (3) the density or occurrence of marine mammals within these
ensonified areas; and, (4) the number of days of activities. We note
that while these factors can contribute to a basic calculation to
provide an initial prediction of potential takes, additional
information that can qualitatively inform take estimates is also
sometimes available (e.g., previous monitoring results or average group
size). Below, we describe the factors considered here in more detail
and present the proposed take estimates.
[[Page 66402]]
Acoustic Thresholds
NMFS recommends the use of acoustic thresholds that identify the
received level of underwater sound above which exposed marine mammals
would be reasonably expected to be behaviorally harassed (equated to
Level B harassment) or to incur PTS of some degree (equated to Level A
harassment).
Level B Harassment--Though significantly driven by received level,
the onset of behavioral disturbance from anthropogenic noise exposure
is also informed to varying degrees by other factors related to the
source or exposure context (e.g., frequency, predictability, duty
cycle, duration of the exposure, signal-to-noise ratio, distance to the
source), the environment (e.g., bathymetry, other noises in the area,
predators in the area), and the receiving animals (hearing, motivation,
experience, demography, life stage, depth) and can be difficult to
predict (e.g., Southall et al., 2007, 2021, Ellison et al., 2012).
Based on what the available science indicates and the practical need to
use a threshold based on a metric that is both predictable and
measurable for most activities, NMFS typically uses a generalized
acoustic threshold based on received level to estimate the onset of
behavioral harassment. NMFS generally predicts that marine mammals are
likely to be behaviorally harassed in a manner considered to be Level B
harassment when exposed to underwater anthropogenic noise above root-
mean-squared pressure received levels (RMS SPL) of 120 dB (referenced
to 1 micropascal (re 1 [mu]Pa)) for continuous (e.g., vibratory pile
driving, drilling) and above RMS SPL 160 dB re 1 [mu]Pa for non-
explosive impulsive (e.g., seismic airguns) or intermittent (e.g.,
scientific sonar) sources.
USCG's proposed activity includes the use impulsive (impact pile
driving) sources, and therefore the RMS SPL threshold of 160 dB re 1
[mu]Pa is applicable.
Level A harassment--NMFS' Technical Guidance for Assessing the
Effects of Anthropogenic Sound on Marine Mammal Hearing (Version 2.0)
(Technical Guidance, 2018) identifies dual criteria to assess auditory
injury (Level A harassment) to five different marine mammal groups
(based on hearing sensitivity) as a result of exposure to noise from
two different types of sources (impulsive or non-impulsive). USCG's
proposed activity includes the use of impulsive (impact pile driving)
sources.
These thresholds are provided in the table below. The references,
analysis, and methodology used in the development of the thresholds are
described in NMFS' 2018 Technical Guidance, which may be accessed at:
<a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance">https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance</a>.
Table 4--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
PTS onset acoustic thresholds \*\ (received level)
Hearing group ------------------------------------------------------------------------
Impulsive Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans........... Cell 1: Lpk,flat: 219 dB; Cell 2: LE,LF,24h: 199 dB.
LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans........... Cell 3: Lpk,flat: 230 dB; Cell 4: LE,MF,24h: 198 dB.
LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans.......... Cell 5: Lpk,flat: 202 dB; Cell 6: LE,HF,24h: 173 dB.
LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater)..... Cell 7: Lpk,flat: 218 dB; Cell 8: LE,PW,24h: 201 dB.
LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater).... Cell 9: Lpk,flat: 232 dB; Cell 10: LE,OW,24h: 219 dB.
LEOW,24h: 203 dB.
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa, and cumulative sound exposure level (LE)
has a reference value of 1[micro]Pa\2\s. In this Table, thresholds are abbreviated to reflect American
National Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as
incorporating frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript
``flat'' is being included to indicate peak sound pressure should be flat weighted or unweighted within the
generalized hearing range. The subscript associated with cumulative sound exposure level thresholds indicates
the designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
and that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could
be exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible,
it is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
exceeded.
Ensonified Area
Here, we describe operational and environmental parameters of the
activity that are used in estimating the area ensonified above the
acoustic thresholds, including source levels and transmission loss
coefficient.
Underwater sound propagation modeling was completed by USCG using
dBSea, a software developed by Marshall Day Acoustics for the modeling
of underwater sound propagation in a variety of environments. The model
was built by importing bathymetry data and placing noise sources in the
environment. Each source can consist of equipment chosen from either
the standard or the user-defined databases. Noise mitigation methods
may also be included. The user has control over the seabed and water
properties including sound speed profile, temperature, salinity, and
current. Noise levels were calculated to the extent of the bathymetry
area. To examine results in more detail, levels may be plotted in cross
sections, or a detailed spectrum may be extracted at any point in the
calculation area. Levels were calculated in third octave bands from
12.5 (hertz) Hz to 20 kHz. Please refer to Acoustic Assessment included
in USCG's application for additional details on the modeling principles
and assumptions.
The representative acoustic modeling scenarios were derived from
descriptions of the expected construction activities through
consultations between the USCG project design and engineering teams.
The scenarios modeled were ones where potential underwater noise
impacts of marine species were anticipated and included impact pile
driving associated with pier installation. All modeling scenarios occur
at a representative location. This location was selected so that the
effects of sound propagation at the range of water column depths
occurring within the project area could be evaluated.
The USCG opted to perform their own acoustic modeling for the Level
A and Level B harassment isopleths as they had site specific
information to input into the model, which may assist in
[[Page 66403]]
providing more accurate results Than, for example, use of NMFS' User
Spreadsheet tool, which is a relatively simple tool that cannot
incorporate site-specific environmental information. The modeling used
by USCG takes into account bathymetry, geo-acoustic properties of sub-
bottom sediments, and sound speed profile. NMFS has reviewed USCG's
modeling and determined that it is acceptable for use here.
A summary of construction and operational scenarios included in the
underwater acoustic modeling analysis is provided in the Acoustic
Assessment and summarized in Table 5 below. The pile diameters selected
for the impact pile driving modeling scenarios were based on maximum
project design considerations approximated by USCG. The Level A and
Level B harassment isopleths for the proposed activities are shown in
Table 6.
Table 5--Source Levels for Impact Pile Installation
----------------------------------------------------------------------------------------------------------------
Pile size Peak SPLs (dB) RMS SPLs (dB) SELss (dB) Source
----------------------------------------------------------------------------------------------------------------
36-in pile....................... 208 190 180 Caltrans 2020.
30-in pile....................... 210 190 177 Caltrans 2020.
----------------------------------------------------------------------------------------------------------------
Table 6--Level A and Level B Harassment Isopleths for Impact Pile Driving
----------------------------------------------------------------------------------------------------------------
Level A harassment zones (m)
------------------------------------------------ Level B
Activity Phocid Otariid harassment
HF cetaceans pinnipeds pinnipeds zone (m)
----------------------------------------------------------------------------------------------------------------
36-in pile...................................... 287 197 0 602
30-in pile...................................... 213 130 0 602
----------------------------------------------------------------------------------------------------------------
Marine Mammal Occurrence and Take Calculation and Estimation
In this section, we provide information about the occurrence of
marine mammals, including density or other relevant information which
will inform the take calculations and describe how the information
provided is synthesized to produce a quantitative estimate of the take
that is reasonably likely to occur and proposed for authorization. The
USCG proposed using marine mammal species densities from the Pacific
Navy Marine Species Density Database to estimate take for marine
mammals. This database incorporates analyzed literature and research
for marine mammal density estimates per season for regions throughout
the U.S. and the USCG based their take estimates on regionally
available population density estimates and site-specific knowledge.
Although this database provides densities for all species present in
the action area, the densities are based on offshore abundance and not
directly relevant to occurrence within in the Columbia River. Following
careful review of the analysis presented by the USCG in its
application, including marine mammal occurrence data, NMFS has
determined that different information inputs than those selected by the
USCG represent the best available scientific information for marine
mammal abundance in the action area. These selections are discussed in
greater detail below.
Steller Sea Lion, California Sea Lion and Harbor Seal
For Steller sea lions, California sea lions, and harbor seals, the
numbers of individuals were referenced from Washington Department of
Fish and Wildlife's (WDFW) surveys from 2000-2014 at the South Jetty
for the months of in water work (November through February) and
averaged to get an estimated daily count (Table 7). While animals were
surveyed at the prominent haul out site along the South Jetty, since
the ETP site is close to the mouth of the river and the South Jetty, we
assumed each of these estimates represents a good proxy for the total
number of individuals that could be present in the project vicinity. We
derived potential take estimates from the average abundance recorded
over the specified period.
Table 7--Pinniped Counts From the South Jetty From 2000-2014
[WDFW 2014]
----------------------------------------------------------------------------------------------------------------
California California
Steller sea Steller sea Sea lion sea lion Harbor seal Harbor seal
lion (monthly) lion (daily) (monthly) (daily) (monthly) (daily)
----------------------------------------------------------------------------------------------------------------
November.................... 1,663 55 1,214 40 0 0
December.................... 1,112 36 725 23 57 2
January..................... 249 8 10 0.3 0 0
February.................... 259 9 28 1 1 0.04
Average (all months)........ 821 27 494 16 15 0.5
----------------------------------------------------------------------------------------------------------------
To calculate the total estimated takes, we multiplied the estimated
days of activity by the associated average daily pinniped counts
(monthly count/days of the month and averaged across all months) for
each species (Table 8).
[[Page 66404]]
Table 8--Estimated Take of Steller Sea Lions, California Sea Lions, and Harbor Seals
--------------------------------------------------------------------------------------------------------------------------------------------------------
Steller sea Steller sea California California
Days of lion lion sea lion sea lion Harbor seal Harbor seal
Pile type and method activity average calculated average calculated average calculate
count take count take count take
--------------------------------------------------------------------------------------------------------------------------------------------------------
36-in Steel Pile Impact Installation......................... 52 27 1,404 16 832 0.5 26
30-in Steel Pile Impact Installation
--------------------------------------------------------------------------------------------------------------------------------------------------------
There is some potential for take by Level A harassment of harbor
seals due to the largest zone being approximately 200 m and because of
the cryptic nature and assumed lower detectability of harbor seals at
this distance. Based on the relative proportion of the area expected to
be ensonified above the Level A harassment threshold for phocid
pinnipeds from impact pile driving (approximately 0.36 square
kilometers (km\2\)) to the area ensonified above the Level B harassment
threshold (1.1 km\2\ for impact pile driving), we estimated that of the
total number of harbor seals that may be located within the greater
Level B harassment zone, approximately 33 percent would approach the
pile driving activities closer and enter the smaller Level A harassment
zone (197 m). Thus, we assume that 33 percent of the total estimated
takes of harbor seals (26 individuals; see Table 9) would be by Level A
harassment. Therefore, we are proposing to authorize 9 takes of harbor
seals by Level A harassment and 17 takes by Level B harassment (Table
10).
The Level A harassment zone for otariid pinnipeds is 0 m. The USCG
would be required to enforce a minimum shutdown zone of 10 m for these
species. At that close range, the USCG would be able to detect
California sea lions and Steller sea lions and implement the required
shutdown measures before any sea lions could enter the Level A
harassment zone. Therefore, no takes of California sea lions or Steller
sea lions by Level A harassment are requested or proposed to be
authorized.
Harbor Porpoise
Harbor porpoises are regularly observed in the coastal waters near
the mouth of the Columbia River and are known to occur year-round,
although this project occurs farther upstream in the Columbia River.
Their nearshore abundance peaks with anchovy presence, which is
generally June through October. However, there was one recorded
sighting of a harbor porpoise in the project area east of the jetties
in the September-November timeframe (OBIS-SEAMAP 2019). During
monitoring for pile driving at the Columbia River Jetty System which is
at the mouth of the Columbia River approximately 23 km from the USCG's
proposed action area, over the course of a 5 day monitoring period,
observers detected 5 harbor porpoises (Grette Associates 2016).
Additionally we reviewed monitoring reports from four recent projects
in the nearby area (Army Corps of Engineers King Pile Markers and Sand
Island Pile Dike Test Piles, and Phase 1 and 2 of the City of Astoria
Bridge Replacement which can be found at: <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities#active-authorizations">https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities#active-authorizations</a>).
Only one project with activities occurring over 15 days had eight
sightings of harbor porpoise at Sand Island Dike.
Given that, there is some potential for harbor porpoise to be
present near the project area, and based on the previously mentioned
monitoring reports sighting data, we calculated that harbor porpoise
could enter the Level B harassment zone every other day of pile driving
(or 0.5/day). To calculate the total estimated takes by Level B
harassment, we multiplied the estimated days of activity by the
associated daily harbor porpoise rate (Table 10).
There is also some potential for take by Level A harassment of
harbor porpoise due to the largest zone being approximately 300 m and
because of the cryptic nature and assumed lower detectability of harbor
porpoise at this distance. The USCG anticipates that 12 harbor
porpoises during impact driving could be taken by Level A harassment.
Take by Level A harassment for harbor porpoise was calculated in the
same way it was for harbor seals. In total, we are proposing to
authorize take of 26 harbor porpoises (Table 10).
Table 10--Proposed Take of Marine Mammals by Level A and Level B Harassment by Species, Stock and Percent of Take by Stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Proposed take Proposed take Total
Species Stock by Level A by Level B proposed Stock Percent of
harassment harassment take abundance stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor Porpoise............................... Northern Oregon/Washington Coast. 12 14 26 21,487 0.1
California sea lion........................... U.S.............................. 0 832 832 257,606 0.3
Steller sea lion.............................. Eastern.......................... 0 1,404 1,404 43,201 3.2
Harbor seal................................... Oregon/Washington Coast.......... 9 17 26 24,732 0.1
--------------------------------------------------------------------------------------------------------------------------------------------------------
Proposed Mitigation
In order to issue an IHA under section 101(a)(5)(D) of the MMPA,
NMFS must set forth the permissible methods of taking pursuant to the
activity, and other means of effecting the least practicable impact on
the species or stock and its habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance, and on
the availability of the species or stock for taking for certain
subsistence uses (latter not applicable for this action). NMFS
regulations require applicants for incidental take authorizations to
include information about the availability and feasibility (economic
and technological) of equipment, methods, and manner of conducting the
activity or other means of effecting the least practicable adverse
impact upon the affected species or stocks, and their habitat (50 CFR
216.104(a)(11)).
[[Page 66405]]
In evaluating how mitigation may or may not be appropriate to
ensure the least practicable adverse impact on species or stocks and
their habitat, as well as subsistence uses where applicable, NMFS
considers two primary factors:
(1) The manner in which, and the degree to which, the successful
implementation of the measure(s) is expected to reduce impacts to
marine mammals, marine mammal species or stocks, and their habitat.
This considers the nature of the potential adverse impact being
mitigated (likelihood, scope, range). It further considers the
likelihood that the measure will be effective if implemented
(probability of accomplishing the mitigating result if implemented as
planned), the likelihood of effective implementation (probability
implemented as planned), and;
(2) The practicability of the measures for applicant
implementation, which may consider such things as cost, and impact on
operations.
Time Restrictions
The USCG has proposed in its description of the project that pile
driving would occur only during daylight hours (no sooner than 30
minutes after sunrise through no later than 30 minutes before sunset),
when visual monitoring of marine mammals can be conducted. In addition,
ODFW requires all in-water construction be limited to the months of
November through February to minimize impacts to ESA listed fish
species.
Mitigation Measures
USCG must follow mitigation measures as specified below:
<bullet> Ensure that construction supervisors and crews, the
monitoring team, and relevant USCG staff are trained prior to the start
of all pile driving activity, so that responsibilities, communication
procedures, monitoring protocols, and operational procedures are
clearly understood. New personnel joining during the project must be
trained prior to commencing work;
<bullet> Employ Protected Species Observers (PSOs) and establish
monitoring locations as described in the application and the IHA. USCG
must monitor the project area to the maximum extent possible based on
the required number of PSOs, required monitoring locations, and
environmental conditions. For all pile driving, at least one PSO must
be used. The PSO will be stationed as close to the activity as
possible;
<bullet> The placement of the PSOs during all pile driving activity
will ensure that the entire shutdown zone, see Table 11, is visible
during pile driving activities. Should environmental conditions
deteriorate such that marine mammals within the entire shutdown zone
will not be visible (e.g., fog, heavy rain), pile driving and removal
must be delayed until the PSO is confident marine mammals within the
shutdown zone could be detected;
<bullet> Monitoring must take place from 30 minutes prior to
initiation of pile driving activity (i.e., pre-clearance monitoring)
through 30 minutes post-completion of pile driving activity;
<bullet> Pre-start clearance monitoring must be conducted during
periods of visibility sufficient for the lead PSO to determine that the
shutdown zones indicated in Table 11 are clear of marine mammals. Pile
driving may commence following 30 minutes of observation when the
determination is made that the shutdown zones are clear of marine
mammals;
<bullet> USCG must use soft start techniques when impact pile
driving. Soft start requires contractors to provide an initial set of
three strikes at reduced energy, followed by a 30 second waiting
period, then two subsequent reduced-energy strike sets. A soft start
must be implemented at the start of each day's impact pile driving and
at any time following cessation of impact pile driving for a period of
30 minutes or longer; and
<bullet> If a marine mammal is observed entering or within the
shutdown zones indicated in Table 11, pile driving must be delayed or
halted. If pile driving is delayed or halted due to the presence of a
marine mammal, the activity may not commence or resume until either the
animal has voluntarily exited and been visually confirmed beyond the
shutdown zone (Table 11) or 15 minutes have passed without re-detection
of the animal.
Shutdown Zones
USCG will establish shutdown zones for all pile driving activities.
The purpose of a shutdown zone is generally to define an area within
which shutdown of the activity would occur upon sighting of a marine
mammal (or in anticipation of an animal entering the defined area).
Shutdown zones would be based upon the Level A harassment zone for each
pile size/type where applicable, as shown in Table 11.
For in-water heavy machinery activities other than pile driving, if
a marine mammal comes within 10 m, work will stop and vessels will
reduce speed to the minimum level required to maintain steerage and
safe working conditions. A 10 m shutdown zone would also serve to
protect marine mammals from physical interactions with project vessels
during pile driving and other construction activities, such as barge
positioning or drilling. If an activity is delayed or halted due to the
presence of a marine mammal, the activity may not commence or resume
until either the animal has voluntarily exited and been visually
confirmed beyond the shutdown zone indicated in Table 11 or 15 minutes
have passed without re-detection of the animal. Construction activities
must be halted upon observation of a species for which incidental take
is not authorized or a species for which incidental take has been
authorized but the authorized number of takes has been met entering or
within the harassment zone.
All marine mammals will be monitored in the Level B harassment
zones and throughout the area as far as visual monitoring can take
place. If a marine mammal enters the Level B harassment zone, in-water
activities will continue and the animal's presence within the estimated
harassment zone will be documented.
USCG will also establish shutdown zones for all marine mammals for
which take has not been authorized or for which incidental take has
been authorized but the authorized number of takes has been met. These
zones are equivalent to the Level B harassment zones for each activity.
If a marine mammal species not covered under this IHA enters the
shutdown zone, all in-water activities will cease until the animal
leaves the zone or has not been observed for at least 15 minutes, and
NMFS will be notified about species and precautions taken. Pile driving
will proceed if the non-IHA species is observed to leave the Level B
harassment zone or if 15 minutes have passed since the last
observation.
If shutdown and/or clearance procedures would result in an imminent
safety concern, as determined by USCG or its designated officials, the
in-water activity will be allowed to continue until the safety concern
has been addressed, and the animal will be continuously monitored.
[[Page 66406]]
Table 11--Shutdown Zones and Monitoring Zones
----------------------------------------------------------------------------------------------------------------
Minimum shutdown zone (m)
Activity ------------------------------------------- Harassment
HF cetaceans Phocid Otariid zone (m)
----------------------------------------------------------------------------------------------------------------
36-in Impact Installation............................ 300 50 10 610
30-in Impact Installation............................ 220 50 10 610
----------------------------------------------------------------------------------------------------------------
Protected Species Observers
The placement of PSOs during all construction activities (described
in the Monitoring and Reporting section) will ensure that the entire
shutdown zone is visible. Should environmental conditions deteriorate
such that the entire shutdown zone would not be visible (e.g., fog,
heavy rain), pile driving would be delayed until the PSO is confident
marine mammals within the shutdown zone could be detected.
PSOs will monitor the full shutdown zones and the Level B
harassment zones to the extent practicable. Monitoring zones provide
utility for observing by establishing monitoring protocols for areas
adjacent to the shutdown zones. Monitoring zones enable observers to be
aware of and communicate the presence of marine mammals in the project
areas outside the shutdown zones and thus prepare for a potential
cessation of activity should the animal enter the shutdown zone.
Based on our evaluation of USCG's planned measures, as well as
other measures considered by NMFS, NMFS has preliminarily determined
that the mitigation measures provide the means effecting the least
practicable impact on the affected species or stocks and their habitat,
paying particular attention to rookeries, mating grounds, and areas of
similar significance.
Proposed Monitoring and Reporting
In order to issue an IHA for an activity, section 101(a)(5)(D) of
the MMPA states that NMFS must set forth requirements pertaining to the
monitoring and reporting of such taking. The MMPA implementing
regulations at 50 CFR 216.104(a)(13) indicate that requests for
authorizations must include the suggested means of accomplishing the
necessary monitoring and reporting that will result in increased
knowledge of the species and of the level of taking or impacts on
populations of marine mammals that are expected to be present while
conducting the activities. Effective reporting is critical both to
compliance as well as ensuring that the most value is obtained from the
required monitoring.
Monitoring and reporting requirements prescribed by NMFS should
contribute to improved understanding of one or more of the following:
<bullet> Occurrence of marine mammal species or stocks in the area
in which take is anticipated (e.g., presence, abundance, distribution,
density);
<bullet> Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) action or environment
(e.g., source characterization, propagation, ambient noise); (2)
affected species (e.g., life history, dive patterns); (3) co-occurrence
of marine mammal species with the activity; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
<bullet> Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors;
<bullet> How anticipated responses to stressors impact either: (1)
long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks;
<bullet> Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important physical components of
marine mammal habitat); and,
<bullet> Mitigation and monitoring effectiveness.
Visual Monitoring
Marine mammal monitoring must be conducted in accordance with the
conditions in this section and the IHA. Marine mammal monitoring during
pile driving activities will be conducted by PSOs meeting the following
requirements:
<bullet> PSOs must be independent of the activity contractor (for
example, employed by a subcontractor) and have no other assigned tasks
during monitoring periods;
<bullet> At least one PSO will have prior experience performing the
duties of a PSO during construction activity pursuant to a NMFS-issued
incidental take authorization;
<bullet> Other PSOs may substitute education (degree in biological
science or related field) or training for experience; and
<bullet> Where a team of three or more PSOs is required, a lead
observer or monitoring coordinator will be designated. The lead
observer will be required to have prior experience working as a marine
mammal observer during construction.
PSOs must have the following additional qualifications:
<bullet> Ability to conduct field observations and collect data
according to assigned protocols;
<bullet> Experience or training in the field identification of
marine mammals, including the identification of behaviors;
<bullet> Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
<bullet> Writing skills sufficient to prepare a report of
observations including but not limited to the number and species of
marine mammals observed; dates and times when in-water construction
activities were conducted; dates, times and reason for implementation
of mitigation (or why mitigation was not implemented when required);
and marine mammal behavior; and
<bullet> Ability to communicate orally, by radio or in person, with
project personnel to provide real-time information on marine mammals
observed in the area as necessary.
<bullet> USCG must employ three PSOs during all pile driving
activities depending on the size of the monitoring and shutdown zones.
A minimum of one PSO must be assigned to monitor waters surrounding the
active pile driving location.
<bullet> USCG must establish the following monitoring locations
with the best views of monitoring zones as described below, in the IHA,
and USCG's application.
<bullet> PSOs would be deployed in strategic locations around the
harassment zone at all times during in-water pile driving. PSOs will be
positioned at locations that provide full views of the impact hammering
monitoring zones and the shutdown zones. PSOs will be stationed on the
staging barges, on shore at the project site, and at the entrance to
the commercial dock area at ETP. All PSOs will have access to high-
quality
[[Page 66407]]
binoculars, range finders to monitor distances, and a compass to record
bearing to animals as well as radios or cells phones for maintaining
contact with work crews.
Monitoring will be conducted 30 minutes before, during, and 30
minutes after all in water construction activities. In addition, PSOs
will record all incidents of marine mammal occurrence, regardless of
distance from activity, and will document any behavioral reactions in
concert with distance from piles being driven or removed. Pile driving
activities include the time to install or remove a single pile or
series of piles, as long as the time elapsed between uses of the pile
driving equipment is no more than 30 minutes.
USCG shall conduct briefings between construction supervisors and
crews, PSOs, USCG staff prior to the start of all pile driving
activities and when new personnel join the work. These briefings will
explain responsibilities, communication procedures, marine mammal
monitoring protocol, and operational procedures.
Reporting
A draft marine mammal monitoring report will be submitted to NMFS
within 90 days after the completion of pile driving and removal
activities, or 60 days prior to a requested date of issuance from any
future IHAs for projects at the same location, whichever comes first.
The report will include an overall description of work completed, a
narrative regarding marine mammal sightings, and associated PSO data
sheets. Specifically, the report must include:
<bullet> Dates and times (begin and end) of all marine mammal
monitoring;
<bullet> Construction activities occurring during each daily
observation period, including the number and type of piles driven or
removed and by what method (i.e., impact) and the total equipment
duration for vibratory removal for each pile or total number of strikes
for each pile (impact driving);
<bullet> PSO locations during marine mammal monitoring;
<bullet> Environmental conditions during monitoring periods (at
beginning and end of PSO shift and whenever conditions change
significantly), including Beaufort sea state and any other relevant
weather conditions including cloud cover, fog, sun glare, and overall
visibility to the horizon, and estimated observable distance;
<bullet> Upon observation of a marine mammal, the following
information:
<bullet> Name of PSO who sighted the animal(s) and PSO location and
activity at the time of sighting;
<bullet> Time of sighting;
<bullet> Identification of the animal(s) (e.g., genus/species,
lowest possible taxonomic level, or unidentifiable), PSO confidence in
identification, and the composition of the group if there is a mix of
species;
<bullet> Distance and bearing of each marine mammal observed
relative to the pile being driven for each sightings (if pile driving
was occurring at time of sighting);
<bullet> Estimated number of animals (min/max/best estimate);
<bullet> Estimated number of animals by cohort (adults, juveniles,
neonates, group composition, sex class, etc.);
<bullet> Animal's closest point of approach and estimated time
spent within the harassment zone;
<bullet> Description of any marine mammal behavioral observations
(e.g., observed behaviors such as feeding or traveling), including an
assessment of behavioral responses thought to have resulted from the
activity (e.g., no response or changes in behavioral state such as
ceasing feeding, changing direction, flushing, or breaching);
<bullet> Number of marine mammals detected within the harassment
zones and shutdown zones; by species;
<bullet> Detailed information about any implementation of any
mitigation triggered (e.g., shutdowns and delays), a description of
specific actions that ensured, and resulting changes in behavior of the
animal(s), if any; and
If no comments are received from NMFS within 30 days, the draft
final report will constitute the final report. If comments are
received, a final report addressing NMFS comments must be submitted
within 30 days after receipt of comments.
Reporting Injured or Dead Marine Mammals
In the event that personnel involved in the construction activities
discover an injured or dead marine mammal, the USCG must immediately
cease the specified activities and report the incident to the Office of
Protected Resources (OPR) (<a href="/cdn-cgi/l/email-protection#c49496ea8d9094ea89abaaadb0abb6adaaa396a1b4abb6b0b784aaaba5a5eaa3abb2"><span class="__cf_email__" data-cfemail="7f2f2d51362b2f51321011160b100d1611182d1a0f100d0b0c3f11101e1e51181009">[email protected]</span></a>), NMFS and
to the West Coast Regional Stranding Coordinator as soon as feasible.
If the death or injury was clearly caused by the specified activity,
USCG must immediately cease the specified activities until NMFS is able
to review the circumstances of the incident and determine what, if any,
additional measures are appropriate to ensure compliance with the terms
of the IHA. The USCG must not resume their activities until notified by
NMFS. The report must include the following information:
<bullet> Time, date, and location (latitude/longitude) of the first
discovery (and updated location information if known and applicable);
<bullet> Species identification (if known) or description of the
animal(s) involved;
<bullet> Condition of the animal(s) (including carcass condition if
the animal is dead);
<bullet> Observed behaviors of the animal(s), if alive;
<bullet> If available, photographs or video footage of the
animal(s); and
<bullet> General circumstances under which the animal was
discovered.
Negligible Impact Analysis and Determination
NMFS has defined negligible impact as an impact resulting from the
specified activity that cannot be reasonably expected to, and is not
reasonably likely to, adversely affect the species or stock through
effects on annual rates of recruitment or survival (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough
information on which to base an impact determination. In addition to
considering estimates of the number of marine mammals that might be
``taken'' through harassment, NMFS considers other factors, such as the
likely nature of any impacts or responses (e.g., intensity, duration),
the context of any impacts or responses (e.g., critical reproductive
time or location, foraging impacts affecting energetics), as well as
effects on habitat, and the likely effectiveness of the mitigation. We
also assess the number, intensity, and context of estimated takes by
evaluating this information relative to population status. Consistent
with the 1989 preamble for NMFS' implementing regulations (54 FR 40338,
September 29, 1989), the impacts from other past and ongoing
anthropogenic activities are incorporated into this analysis via their
impacts on the baseline (e.g., as reflected in the regulatory status of
the species, population size and growth rate where known, ongoing
sources of human-caused mortality, or ambient noise levels).
To avoid repetition, our analysis applies to all species listed in
Table 2 for which take could occur, given that NMFS expects the
anticipated effects of the proposed pile driving/removal on different
marine mammal stocks to be similar in nature. Where there are
meaningful differences between species
[[Page 66408]]
or stocks, or groups of species, in anticipated individual responses to
activities, impact of expected take on the population due to
differences in population status, or impacts on habitat, NMFS has
identified species-specific factors to inform the analysis.
Pile driving activities associated with the USCG construction
project have the potential to disturb or displace marine mammals.
Specifically, the project activities may result in take, in the form of
Level A and Level B harassment, from underwater sounds generated from
pile driving. Potential takes could occur if individuals are present in
the ensonified zone when these activities are underway.
No serious injury or mortality would be expected, even in the
absence of required mitigation measures, given the nature of the
activities. Further, limited take by Level A harassment is proposed for
two species, but the potential for harassment would be minimized
through the construction method and the implementation of the planned
mitigation measures (see Proposed Mitigation section).
Take by Level A harassment is proposed for harbor seals and harbor
porpoise to account for the possibility that an animal could enter a
Level A harassment zone prior to detection, and remain within that zone
for a duration long enough to incur PTS before being observed and the
USCG shutting down pile driving activity. Any take by Level A
harassment is expected to arise from, at most, a small degree of PTS,
i.e., minor degradation of hearing capabilities within regions of
hearing that align most completely with the energy produced by impact
pile driving (i.e., the low-frequency region below 2 kHz), not severe
hearing impairment or impairment within the ranges of greatest hearing
sensitivity. Animals would need to be exposed to higher levels and/or
longer duration than are expected to occur here in order to incur any
more than a small degree of PTS.
Further, the amount of authorized take by Level A harassment is
very low for both marine mammal species. If hearing impairment occurs,
it is most likely that the affected animal would lose only a few
decibels in its hearing sensitivity. Due to the small degree
anticipated, any PTS potential incurred would not be expected to affect
the reproductive success or survival of any individuals, much less
result in adverse impacts on the species or stock.
Additionally, some subset of the individuals that are behaviorally
harassed could also simultaneously incur some small degree of TTS for a
short duration of time. However, since the hearing sensitivity of
individuals that incur TTS is expected to recover completely within
minutes to hours, it is unlikely that the brief hearing impairment
would affect the individual's long-term ability to forage and
communicate with conspecifics, and would therefore not likely impact
reproduction or survival of any individual marine mammal, let alone
adversely affect rates of recruitment or survival of the species or
stock.
The Level A harassment zones identified in Table 5 are based upon
an animal's exposure to pile driving of up to three steel piles per
day. Given the short duration to impact drive each pile and break
between pile installations (to reset equipment and move piles into
place), an animal would have to remain within the area estimated to be
ensonified above the Level A harassment threshold for multiple hours.
This is highly unlikely given marine mammal movement in the area. If an
animal was exposed to accumulated sound energy, the resulting PTS would
likely be small (e.g., PTS onset) at lower frequencies where pile
driving energy is concentrated, and unlikely to result in impacts to
individual fitness, reproduction, or survival.
The nature of the pile driving project precludes the likelihood of
serious injury or mortality. For all species and stocks, take would
occur within a limited, confined area (adjacent to the project site) of
the stock's range. Level A and Level B harassment will be reduced to
the level of least practicable adverse impact through use of mitigation
measures described herein. Further, the amount of take proposed to be
authorized is small when compared to stock abundance.
Behavioral responses of marine mammals to pile driving in the
Columbia River are expected to be mild, short term, and temporary.
Marine mammals within the Level B harassment zones may not show any
visual cues they are disturbed by activities or they could become
alert, avoid the area, leave the area, or display other mild responses
that are not observable, such as changes in vocalization patterns.
Given that pile driving would occur for only a portion of the project's
duration, any harassment occurring would be temporary. Additionally,
many of the species present in region would only be present temporarily
based on seasonal patterns or during transit between other habitats.
These temporarily present species would be exposed to even smaller
periods of noise-generating activity, further decreasing the impacts.
For all species, there are no known BIA near the project area that
would be impacted by USCG's planned activities. While California sea
lions and harbor seals are the species most likely to occur within the
immediate project area the nearest haul out for both species is
approximately 3 miles (4.8 km) away. There are three known haul out
sites for both species near the project area including Tongue Point
Sands, Taylor Sands, and Green Island/Sanborn Slough, the closest being
Tongue Point Sands 3 miles (4.8 km) from the project area.
Additionally, there is a Steller sea lion haul out in the Columbia
River; it is approximately 15 miles (24.1 km) away from the project
site at the south jetty off the western shoreline of Fort Stevens State
Park. None of these haul outs are in the immediate project vicinity.
In addition, it is unlikely that minor noise effects in a small,
localized area of habitat would have any effect on each stock's
continued survival. In combination, we believe that these factors, as
well as the available body of evidence from other similar activities,
demonstrate that the potential effects of the specified activities will
have only minor, short-term effects on individuals. The specified
activities are not expected to impact rates of recruitment or survival
and will therefore not result in population-level impacts.
In summary and as described above, the following factors primarily
support our preliminary determination that the impacts resulting from
this activity are not expected to adversely affect any of the species
or stocks through effects on annual rates of recruitment or survival:
<bullet> No serious injury or mortality is anticipated or proposed
to be authorized;
<bullet> Authorized Level A harassment would be very small amounts
and of low degree;
<bullet> For all species, the mouth of the Columbia River is a very
small and peripheral part of their range;
<bullet> The intensity of anticipated takes by Level B harassment
is relatively low for all stocks. Level B harassment would be primarily
in the form of behavioral disturbance, resulting in avoidance of the
project areas around where impact or vibratory pile driving is
occurring, with some low-level TTS that may limit the detection of
acoustic cues for relatively brief amounts of time in relatively
confined footprints of the activities;
<bullet> Effects on species that serve as prey for marine mammals
from the activities are expected to be short-term and, therefore, any
associated impacts on marine mammal feeding are not
[[Page 66409]]
expected to result in significant or long-term consequences for
individuals, or to accrue to adverse impacts on their populations;
<bullet> The ensonified areas are very small relative to the
overall habitat ranges of all species and stocks;
<bullet> The lack of anticipated significant or long-term negative
effects to marine mammal habitat; and
<bullet> USCG would implement mitigation measures including soft
starts and shutdown zones to minimize the numbers of marine mammals
exposed to injurious levels of sound, and to ensure that take by Level
A harassment is, at most, a small degree of PTS.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the proposed monitoring and
mitigation measures, NMFS preliminarily finds that the total marine
mammal take from the proposed activities will have a negligible impact
on all affected marine mammal species or stocks.
Small Numbers
As noted previously, only take of small numbers of marine mammals
may be authorized under sections 101(a)(5)(A) and (D) of the MMPA for
specified activities other than military readiness activities. The MMPA
does not define small numbers and so, in practice, where estimated
numbers are available, NMFS compares the number of individuals taken to
the most appropriate estimation of abundance of the relevant species or
stock in our determination of whether an authorization is limited to
small numbers of marine mammals. When the predicted number of
individuals to be taken is fewer than one-third of the species or stock
abundance, the take is considered to be of small numbers. Additionally,
other qualitative factors may be considered in the analysis, such as
the temporal or spatial scale of the activities. For all species, the
proposed take is below one third of the population for all marine
mammal stocks (Table 10).
Based on the analysis contained herein of the proposed activity
(including the proposed mitigation and monitoring measures) and the
anticipated take of marine mammals, NMFS preliminarily finds that small
numbers of marine mammals would be taken relative to the population
size of the affected species or stocks.
Unmitigable Adverse Impact Analysis and Determination
There are no relevant subsistence uses of the affected marine
mammal stocks or species implicated by this action. Therefore, NMFS has
determined that the total taking of affected species or stocks would
not have an unmitigable adverse impact on the availability of such
species or stocks for taking for subsistence purposes.
Endangered Species Act
Section 7(a)(2) of the Endangered Species Act of 1973 (ESA; 16
U.S.C. 1531 et seq.) requires that each Federal agency insure that any
action it authorizes, funds, or carries out is not likely to jeopardize
the continued existence of any endangered or threatened species or
result in the destruction or adverse modification of designated
critical habitat. To ensure ESA compliance for the issuance of IHAs,
NMFS consults internally whenever we propose to authorize take for
endangered or threatened species.
No incidental take of ESA-listed species is proposed for
authorization or expected to result from this activity. Therefore, NMFS
has determined that formal consultation under section 7 of the ESA is
not required for this action.
Proposed Authorization
As a result of these preliminary determinations, NMFS proposes to
issue an IHA to the USCG for conducting impact pile driving associated
with the ETP project in Astoria, Oregon, provided the previously
mentioned mitigation, monitoring, and reporting requirements are
incorporated. A draft of the proposed IHA can be found at: <a href="https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities">https://www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-construction-activities</a>.
Request for Public Comments
We request comment on our analyses, the proposed authorization, and
any other aspect of this notice of proposed IHA for the proposed
construction project. We also request comment on the potential renewal
of this proposed IHA as described in the paragraph below. Please
include with your comments any supporting data or literature citations
to help inform decisions on the request for this IHA or a subsequent
renewal IHA.
On a case-by-case basis, NMFS may issue a one-time, 1 year renewal
IHA following notice to the public providing an additional 15 days for
public comments when (1) up to another year of identical or nearly
identical activities as described in the Description of Proposed
Activity section of this notice is planned or (2) the activities as
described in the Description of Proposed Activity section of this
notice would not be completed by the time the IHA expires and a renewal
would allow for completion of the activities beyond that described in
the Dates and Duration section of this notice, provided all of the
following conditions are met:
<bullet> A request for renewal is received no later than 60 days
prior to the needed renewal IHA effective date (recognizing that the
renewal IHA expiration date cannot extend beyond 1 year from expiration
of the initial IHA).
<bullet> The request for renewal must include the following:
(1) An explanation that the activities to be conducted under the
requested renewal IHA are identical to the activities analyzed under
the initial IHA, are a subset of the activities, or include changes so
minor (e.g., reduction in pile size) that the changes do not affect the
previous analyses, mitigation and monitoring requirements, or take
estimates (with the exception of reducing the type or amount of take).
(2) A preliminary monitoring report showing the results of the
required monitoring to date and an explanation showing that the
monitoring results do not indicate impacts of a scale or nature not
previously analyzed or authorized.
Upon review of the request for renewal, the status of the affected
species or stocks, and any other pertinent information, NMFS determines
that there are no more than minor changes in the activities, the
mitigation and monitoring measures will remain the same and
appropriate, and the findings in the initial IHA remain valid.
Dated: September 18, 2023.
Catherine Marzin,
Acting Director, Office of Protected Resources, National Marine
Fisheries Service.
[FR Doc. 2023-20534 Filed 9-26-23; 8:45 am]
BILLING CODE 3510-22-P
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This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.