Notice2026-05744
Marine Mammals; Incidental Take During Specified Activities; Proposed Incidental Harassment Authorization for Southeast Alaska Stock of Northern Sea Otters in Angoon, Alaska
Primary source
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Published
March 25, 2026
Issuing agencies
Interior DepartmentFish and Wildlife Service
Abstract
We, the U.S. Fish and Wildlife Service (FWS), in response to a request under the Marine Mammal Protection Act of 1972, as amended, from Alaska Department of Transportation and Public Facilities, propose to authorize nonlethal, incidental take by harassment of small numbers of Southeast Alaska stock northern sea otters (Enhydra lutris kenyoni) from May 1, 2026, to April 30, 2027. The applicant has requested this authorization for take by harassment that may result from activities associated with pile driving and marine construction within Killisnoo Harbor in Angoon, Alaska. We estimate that this project may result in, and propose to authorize, the nonlethal incidental take by harassment of up to 34 northern sea otters from the Southeast Alaska stock. Neither the applicant nor the FWS anticipate any lethal take, and the FWS does not propose to authorize any lethal take. We invite comments on the proposed incidental harassment authorization and the accompanying draft environmental assessment from the public, Tribes, and local, State, and Federal agencies.
Full Text
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<title>Federal Register, Volume 91 Issue 57 (Wednesday, March 25, 2026)</title>
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[Federal Register Volume 91, Number 57 (Wednesday, March 25, 2026)]
[Notices]
[Pages 14568-14583]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2026-05744]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
[Docket No. FWS-R7-ES-2025-1232; FXES111607MRG01-267-FF07CAMM00]
Marine Mammals; Incidental Take During Specified Activities;
Proposed Incidental Harassment Authorization for Southeast Alaska Stock
of Northern Sea Otters in Angoon, Alaska
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Notice of receipt of application; proposed incidental
harassment
[[Page 14569]]
authorization; draft environmental assessment; request for comments.
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SUMMARY: We, the U.S. Fish and Wildlife Service (FWS), in response to a
request under the Marine Mammal Protection Act of 1972, as amended,
from Alaska Department of Transportation and Public Facilities, propose
to authorize nonlethal, incidental take by harassment of small numbers
of Southeast Alaska stock northern sea otters (Enhydra lutris kenyoni)
from May 1, 2026, to April 30, 2027. The applicant has requested this
authorization for take by harassment that may result from activities
associated with pile driving and marine construction within Killisnoo
Harbor in Angoon, Alaska. We estimate that this project may result in,
and propose to authorize, the nonlethal incidental take by harassment
of up to 34 northern sea otters from the Southeast Alaska stock.
Neither the applicant nor the FWS anticipate any lethal take, and the
FWS does not propose to authorize any lethal take. We invite comments
on the proposed incidental harassment authorization and the
accompanying draft environmental assessment from the public, Tribes,
and local, State, and Federal agencies.
DATES: Comments must be received by April 24, 2026.
ADDRESSES:
Document availability: You may view the application package, the
draft environmental assessment, and other supporting material at
<a href="https://www.regulations.gov">https://www.regulations.gov</a> under Docket No. FWS-R7-ES-2025-1232, or
you may request these documents from the person listed under FOR
FURTHER INFORMATION CONTACT.
Comment submission: You may submit comments on the proposed
authorization by one of the following methods:
<bullet> Electronic submission: Go to the Federal eRulemaking
Portal: <a href="https://www.regulations.gov">https://www.regulations.gov</a>. In the Search box, enter FWS-R7-
ES-2025-1232, which is the docket number for this rulemaking action.
Then, click on the ``Search'' button. On the resulting page, in the
panel on the left side of the screen under the ``Document Type''
heading, check the Notice box to locate this document. You may submit a
comment by clicking on ``Comment.'' Comments must be submitted to
<a href="https://www.regulations.gov">https://www.regulations.gov</a> before 11:59 p.m. (Eastern Time) on the
date specified in DATES.
<bullet> U.S. mail: Public Comments Processing, Attn: Docket No.
FWS-R7-ES-2025-1232, U.S. Fish and Wildlife Service, MS: PRB (JAO/3W),
5275 Leesburg Pike, Falls Church, VA 22041-3803.
We request that you send comments only by the methods described
above. We will post all comments at <a href="https://www.regulations.gov">https://www.regulations.gov</a>. You
may request that we withhold personal identifying information from
public review; however, we cannot guarantee that we will be able to do
so. See Request for Public Comments for more information.
FOR FURTHER INFORMATION CONTACT: Stephanie Burgess, by email at
<a href="/cdn-cgi/l/email-protection#582a6f3535352a3d3f2d34392c372a21183e2f2b763f372e"><span class="__cf_email__" data-cfemail="7301441e1e1e011614061f12071c010a331504005d141c05">[email protected]</span></a>, by telephone at 907-786-3800, or by U.S. mail
at U.S. Fish and Wildlife Service, MS 341, 1011 East Tudor Road,
Anchorage, AK 99503. Individuals in the United States who are deaf,
deafblind, hard of hearing, or have a speech disability may dial 711
(TTY, TDD, or TeleBraille) to access telecommunications relay services.
Individuals outside the United States should use the relay services
offered within their country to make international calls to the point-
of-contact in the United States.
SUPPLEMENTARY INFORMATION:
Background
Section 101(a)(5)(D) of the Marine Mammal Protection Act of 1972
(MMPA; 16 U.S.C. 1361, et seq.) authorizes the Secretary of the
Interior (Secretary) to allow, upon request, the incidental, but not
intentional, taking by harassment of small numbers of certain marine
mammals in response to requests by U.S. citizens (as defined in title
50 of the Code of Federal Regulations (CFR) in part 18, at 50 CFR
18.27(c)) engaged in a specified activity (other than commercial
fishing) within a specified geographic region during a period of not
more than 1 year. The Secretary has delegated authority for
implementation of the MMPA to the U.S. Fish and Wildlife Service (FWS,
or we). According to the MMPA, the FWS shall allow this incidental
taking by harassment if we find that the total of such taking for the
1-year period:
1. Will affect only small numbers of individuals of the species or
stock;
2. Will have no more than a negligible impact on the species or
stock; and
3. Will not have an unmitigable adverse impact on the availability
of these species or stock for taking for subsistence use by Alaska
Natives.
If the requisite findings are made, we issue an authorization that
sets forth the following, where applicable:
1. Permissible methods of taking;
2. Means of effecting the least practicable adverse impact on the
species or stock and its habitat and the availability of the species or
stock for subsistence uses; and
3. Requirements for monitoring and reporting of such taking by
harassment, including, in certain circumstances, requirements for the
independent peer review of proposed monitoring plans or other research
proposals.
The term ``take'' means to ``harass, hunt, capture, or kill, or to
attempt to harass, hunt, capture, or kill any marine mammal'' (16
U.S.C. 1362(13)). Harassment for activities other than military
readiness activities or scientific research conducted by or on behalf
of the Federal Government means any act of pursuit, torment, or
annoyance that has the potential to injure a marine mammal or marine
mammal stock in the wild (the MMPA defines this as ``Level A
harassment''), or 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 (the MMPA defines this as ``Level B
harassment'') (16 U.S.C. 1362(18)).
The terms ``negligible impact'' and ``unmitigable adverse impact''
are defined in 50 CFR 18.27(c) (i.e., regulations governing small takes
of marine mammals incidental to specified activities) as follows:
``Negligible impact'' is 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. ``Unmitigable adverse impact''
means an impact resulting from the specified activity: (1) that is
likely to reduce the availability of the species to a level
insufficient for a harvest to meet subsistence needs by (i) causing the
marine mammals to abandon or avoid hunting areas, (ii) directly
displacing subsistence users, or (iii) placing physical barriers
between the marine mammals and the subsistence hunters; and (2) that
cannot be sufficiently mitigated by other measures to increase the
availability of marine mammals to allow subsistence needs to be met.
The term ``small numbers'' is also defined in 50 CFR 18.27(c).
However, we do not rely on that definition here as it conflates ``small
numbers'' with ``negligible impacts.'' We recognize ``small numbers''
and ``negligible impacts'' as two separate and distinct considerations
when reviewing requests for incidental harassment authorizations (IHA)
under the MMPA (see Natural Res. Def. Council, Inc. v. Evans, 232 F.
Supp. 2d 1003, 1025 (N.D. Cal. 2003)). Instead, for our small numbers
[[Page 14570]]
determination, we estimate the likely number of marine mammals to be
taken and evaluate if that take is small relative to the size of the
species or stock.
The term ``least practicable adverse impact'' is not defined in the
MMPA or its enacting regulations. In processing requests for IHAs, we
ensure the least practicable adverse impact by requiring mitigation
measures that are effective in reducing the impact of specified
activities, but they are not so restrictive as to make specified
activities unduly burdensome or impossible to undertake and complete.
Summary of Request
On November 13, 2024, the FWS received a request prepared by
Solstice Alaska Consulting, Inc. on behalf of Alaska Department of
Transportation and Public Facilities (hereafter, DOT&PF or the
applicant) for an authorization to take by harassment a small number of
northern sea otters (Enhydra lutris kenyoni) (hereafter, sea otters
unless another sea otter subspecies is specified) from the Southeast
Alaska stock. The applicant expects take by harassment may occur during
their construction modifications to the existing Angoon Ferry Terminal
within Killisnoo Harbor in Angoon, Alaska. The FWS requested additional
information on project activities, geospatial files of the project
impact area, and mitigation measures, and the DOT&PF provided the
requested information. We received a revised request on May 8, 2025.
The FWS determined the May 8, 2025, application to be adequate and
complete.
Description of Specified Geographic Region and Specified Activities
The specified geographic region is the nearshore waters surrounding
the Angoon Ferry Terminal located within Killisnoo Harbor in Angoon,
Alaska (figure 1 below).
[GRAPHIC] [TIFF OMITTED] TN25MR26.005
The specified activity (hereafter project) will include installing
three new floating fender dolphins, modifying an existing floating
donut fender pile, relocating one of the mooring dolphins, upgrading
the actuated bridge and apron lift system, and improving the dock's
transfer bridge at the Angoon Ferry Terminal within Killisnoo Harbor in
Angoon, Alaska. The applicant, DOT&PF, plans to remove a total of 3
steel piles that are no greater than 61.0 centimeters (cm) (24 inches
[in]) in diameter using direct-pull and vibratory pile driving methods
and cutting the steel cable anchors for each of these piles at the
mudline using an exothermic cutting torch. A total of 16 temporary
steel piles, each 61.0 cm (24 in) in diameter, will be installed and
removed using vibratory pile driving to guide permanent piles into
place. The applicant plans to install a total of 18 permanent steel
piles no greater than
[[Page 14571]]
76.2 cm (30 in) in diameter using a combination of vibratory pile
driving, impact pile driving, and down-the-hole (DTH) drilling of rock
sockets and tension anchors, which are 20.3 cm (8 in) in diameter.
Hereafter (unless otherwise specified), the terms ``pile driving'' and
``pile-driving activities'' are used to refer to both pile installation
and pile removal. In-water project activities are summarized in table 1
below.
Table 1--DOT&PF Angoon Ferry Terminal Project Activities, Piles Installed or Removed, and Days of Activity
----------------------------------------------------------------------------------------------------------------
Maximum number Maximum number
Project component Pile size and Activity Total number of piles per of days of
material of piles day activity
----------------------------------------------------------------------------------------------------------------
Demolition................... 50.8-cm (20-in) Removal--vibrat 2 2 2
steel. ory.
61.0-cm (24-in) Removal--vibrat 1 1 1
steel. ory.
Construction................. 61.0-cm (24-in) Temporary 16 4 16
steel. installation--
vibratory.
Temporary 4 16
removal--vibra
tory.
50.8-cm (20-in) Installation--v 2 2 2
steel. ibratory.
Installation--i 2 4
mpact.
Installation--t 2 7
ension anchor
DTH.
61.0-cm (24-in) Installation--v 5 4 5
steel. ibratory.
Installation--i 4 10
mpact.
Installation--t 2 16
ension anchor
DTH.
76.2-cm (30-in) Installation--v 11 4 11
steel. ibratory.
Installation--i 4 22
mpact.
Installation--t 8 2 25
ension anchor
DTH.
Installation--r 3 1 10
ock socket DTH.
----------------------------------------------------------------------------------------------------------------
Pile-driving activities will occur over 147 non-consecutive days
for approximately 106 hours between May 1, 2026, and April 30, 2027.
Materials and equipment will be transported via barges to the project
location. The applicant will also use a construction barge to support
construction operations. A small skiff may also be used to support
construction operations and transport personnel to and from the
construction barge. Additional project details may be reviewed in the
application materials available as described under ADDRESSES or may
also be requested as described under FOR FURTHER INFORMATION CONTACT.
Description of Marine Mammals in the Specified Geographic Region
The northern sea otter is the only marine mammal species under the
FWS's jurisdiction likely to be found within the specified geographic
region. Information on the range, stocks, and biology of sea otters is
included in supplemental information, which can be found as described
above in ADDRESSES.
Potential Impacts of the Specified Activities on Marine Mammals
Effects of Noise on Sea Otters
We characterize ``noise'' as sound released into the environment
from human activities that exceeds ambient levels or interferes with
normal sound production or reception by sea otters. The terms
``acoustic disturbance'' and ``acoustic harassment'' are disturbances
or harassment events resulting from noise exposure. Potential effects
of noise exposure are likely to depend on the sea otter's distance from
the sound source, the sound level and intensity the sea otter receives,
background noise levels, noise frequency, noise duration, and whether
the noise is pulsed or continuous. The actual noise level perceived by
individual sea otters will also depend on whether the sea otter is
above or below water and atmospheric and environmental conditions.
Temporary disturbance of sea otters or localized displacement reactions
are the most likely effects to occur from noise exposure.
Sea Otter Hearing
Pile driving and marine construction activities produce sound
within sea otters' hearing range. Controlled sound exposure trials on
southern sea otters (Enhydra lutris nereis) indicate that sea otters
can hear frequencies between 125 hertz (Hz) and 38 kilohertz (kHz),
with best sensitivity between 1.2 and 27 kHz (Ghoul and Reichmuth
2014). Sea otters are more adept at aerial hearing and their
sensitivity is similar to that of terrestrial carnivores (Reichmuth and
Ghoul 2012; Ghoul and Reichmuth 2016; Zellmer et al. 2021). Aerial and
underwater audiograms for a captive adult male southern sea otter in
the presence of ambient noise suggest the sea otter's hearing was less
sensitive to high-frequency (greater than 22 kHz) and low-frequency
(less than 2 kHz) sound than that of terrestrial mustelids but was
similar to that of a California sea lion (Zalophus californianus).
However, the sea otter was still able to hear low-frequency sounds, and
the detection thresholds for sounds between 0.125 and 1 kHz were
between 116 and 101 decibels (dB), respectively. Dominant frequencies
of southern sea otter vocalizations are between 3 and 8 kHz, with some
energy extending above 60 kHz (McShane et al. 1995; Ghoul and Reichmuth
2012).
Exposure to high levels of sound may cause changes in behavior,
masking of communications, temporary or permanent changes in hearing
sensitivity, discomfort, and injury to marine mammals. Sea otters do
not rely on sound to orient themselves, locate prey, or communicate
under water; therefore, masking of communications by anthropogenic
noise is less of a concern than for other marine mammals. However, sea
otters, especially mothers and pups, do use sound for communication in
air (McShane et al. 1995), and sea otters may monitor underwater sound
to avoid predators (Davis et al. 1987).
Exposure Thresholds
Underwater Sounds
Noise exposure criteria for identifying underwater noise levels
capable of causing Level A harassment (injury) to marine mammal
species, including sea otters, have been established using the same
methods as those used by the National Marine Fisheries Service (NMFS)
(Southall et al. 2019). These criteria are based on estimated levels of
sound exposure capable of causing a permanent shift in hearing
sensitivity (i.e., a permanent threshold shift (PTS) (NMFS 2018)). A
PTS occurs when noise exposure causes damage to hair cells within the
inner ear system (Ketten
[[Page 14572]]
2012). A sea otter that experiences PTS would be permanently unable to
hear certain sounds at frequencies similar to those that caused the
initial injury. Although the effects of PTS are, by definition,
permanent, PTS does not equate to total hearing loss.
Sound exposure thresholds incorporate two metrics of exposure: the
peak level of instantaneous exposure likely to cause PTS, and the
cumulative sound exposure level (SEL<INF>CUM</INF>) during a 24-hour
period. They also include weighting adjustments for the sensitivity of
different species to varying frequencies. The PTS-based injury criteria
were developed from theoretical extrapolation of observations of
temporary threshold shifts (TTS) detected in lab settings during sound
exposure trials (Finneran 2015). A TTS is a noise-induced threshold
shift in hearing sensitivity that fully recovers over time (Finneran
2015). Southall et al. (2019) developed TTS thresholds for sea otters,
which are included in the ``other marine carnivores'' category, of 188
dB SEL<INF>CUM</INF> for impulsive sounds and 199 dB SEL<INF>CUM</INF>
for nonimpulsive sounds. Based on these analyses, Southall et al.
(2019) predict that PTS for sea otters will occur at 232 dB peak sound
pressure level (SPL) or 203 dB SEL<INF>CUM</INF> for impulsive
underwater sound and 219 dB SEL<INF>CUM</INF> for nonimpulsive
underwater sound.
The NMFS (2018) criteria do not identify thresholds for avoidance
of Level B harassment. For pinnipeds (seals and sea lions), NMFS has
adopted a 160-dB threshold for Level B harassment from exposure to
impulsive noise and a 120-dB threshold for nonimpulsive noise (High
Energy Seismic Survey Team 1999; NMFS 2018). These thresholds were
developed from observations of mysticete (baleen) whales responding to
airgun operations (e.g., Malme et al. 1983; Malme and Miles 1983;
Richardson et al. 1986, 1995). Southall et al. (2007, 2019) assessed
behavioral response studies and found considerable variability among
pinnipeds. The authors determined that exposures between approximately
90 to 140 dB generally do not appear to induce strong behavioral
responses from pinnipeds in water. However, they found behavioral
effects, including avoidance, become more likely in the range between
120 and 160 dB, and most marine mammals showed some, albeit variable,
responses to sound between 140 and 180 dB. Wood et al. (2012) adapted
the approach identified in Southall et al. (2007) to develop a
probabilistic scale for marine mammal taxa at which 10 percent, 50
percent, and 90 percent of individuals exposed are assumed to produce a
behavioral response. For many marine mammals, including pinnipeds,
these response rates were set at SPLs of 140, 160, and 180 dB,
respectively.
We have evaluated these thresholds and determined that the Level B
harassment threshold of 120 dB for nonimpulsive noise is not applicable
to sea otters. The 120-dB threshold is based on studies in which gray
whales (Eschrichtius robustus) were exposed to experimental playbacks
of industrial noise (Malme et al. 1983; Malme and Miles 1983). During
these playback studies, southern sea otter responses to industrial
noise were also monitored (Riedman 1983, 1984). While gray whales
exhibited avoidance to industrial noise at the 120-dB threshold, there
was no evidence of disturbance reactions or avoidance in southern sea
otters. Thus, given the differences in hearing and behavior between sea
otters and gray whales, the NMFS 120-dB threshold based on gray whale
behavior is not appropriate for predicting sea otter behavioral
responses.
Based on the lack of sea otter disturbance response or any other
reaction to the playback studies from the 1980s, as well as the absence
of a clear pattern of disturbance or avoidance behaviors attributable
to underwater sound levels up to about 160 dB resulting from low-
frequency broadband noise, we assume 120 dB is not an appropriate
behavioral response threshold for sea otters exposed to nonimpulsive
underwater noise.
Based on the best available scientific information about sea otters
and closely related marine mammals where sea otter data are limited,
the FWS has set 160 dB of received underwater sound as a threshold for
take by Level B harassment of sea otters in this proposed IHA. Exposure
to in-water noise levels between 125 Hz and 38 kHz that are greater
than 160 dB--for both impulsive and nonimpulsive sound sources--will be
considered by the FWS as Level B harassment. Thresholds for Level A
harassment (which entails the potential for injury) for in-water noise
levels between 125 Hz and 38 kHz are 232 dB peak SPL or 203 dB
SEL<INF>CUM</INF> for impulsive sounds and 219 dB SEL<INF>CUM</INF> for
nonimpulsive sounds (table 2 below).
Airborne Sounds
The NMFS (2018) guidance neither addresses thresholds for
preventing injury or disturbance from airborne noise, nor provides
thresholds for avoidance of Level B harassment. Conveyance of
underwater noise into the air is of little concern since the effects of
pressure release and interference at the water's surface reduce
underwater noise transmission into the air. For activities that create
both in-air and underwater noise, we will estimate take based on
parameters for underwater noise transmission. Considering sound energy
travels more efficiently through water than through air, this
estimation will also account for exposures to sea otters at the
surface.
Table 2--Temporary Threshold Shift (TTS) and Permanent Threshold Shift (PTS) Thresholds
[Established by Southall et al. (2019) through modeling and extrapolation for ``Other Marine Carnivores'', which include sea otters.*]
--------------------------------------------------------------------------------------------------------------------------------------------------------
TTS PTS
------------------------------------------------------------------------------------------------
nonimpulsive impulsive nonimpulsive impulsive
------------------------------------------------------------------------------------------------
SELCUM SELCUM Peak SPL SELCUM SELCUM Peak SPL
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air.................................................... 157 146 170 177 161 176
Water.................................................. 199 188 226 219 203 232
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Values are weighted for other marine carnivores' hearing thresholds and given in cumulative sound exposure level (SELCUM dB re (20 micropascal
[[micro]Pa] in air and SELCUM dB re 1 [micro]Pa in water) for impulsive and nonimpulsive sounds, and unweighted peak sound pressure level (SPL) in air
(dB re 20[micro]Pa) and water (dB 1[micro]Pa) (impulsive sounds only).
[[Page 14573]]
Evidence From Sea Otter Studies
Individual sea otters near the Angoon Ferry Terminal project
location would likely show a range of responses to noise from pile-
driving activities. Some sea otters would likely dive, show startle
responses, change direction of travel, or prematurely surface. Sea
otters reacting to pile-driving activities may divert time and
attention from biologically important behaviors, such as feeding and
nursing pups. Sea otter responses to disturbance can result in
energetic costs. For example, sea otters spend more time traveling in
areas with high levels of disturbance (Curland 1997). Higher energetic
costs require increased amounts of prey consumption (Barrett 2019).
This increased prey consumption may impact sea otter prey availability
and cause sea otters to spend more time foraging and less time resting
(Barrett 2019). Some sea otters may abandon the project area and return
when the disturbance has ceased. Based on the observed movement
patterns of sea otters (Lensink 1962; Kenyon 1969, 1981; Garshelis and
Garshelis 1984; Riedman and Estes 1990), we expect some sea otters
would respond to pile-driving activities by dispersing to nearby areas
of suitable habitat; however, other sea otters, especially territorial
adult males, would not be displaced.
Additional information on the evidence from studies about how sea
otters may be affected by noise can be found in the supplemental
information to this document (available as described above in
ADDRESSES).
Consequences of Permanent Threshold Shift
Sea otters exposed to noise levels above Level A harassment
threshold criteria may experience a permanent shift in the sensitivity
of their hearing. Information on the consequences of a permanent
threshold shift in sea otter hearing due to noise exposure can be found
in the supplemental information to this document (available as
described above in ADDRESSES).
Consequences of Disturbance
Information on the consequences of disturbance to sea otters can be
found in the supplemental information to this document (available as
described above in ADDRESSES).
Vessel Activities
Vessel activity during the project includes the use of barges to
transport and stage equipment and materials to support construction
operations. A skiff may also be used to support construction
operations. Vessels will not be used extensively or over a long
duration during project activities. We do not anticipate that sea
otters would experience changes in behavior indicative of harassment
during vessel operations. Additionally, vessel operators would take
every precaution to avoid harassment of sea otters when operating a
vessel near sea otters and implement mitigation measures described in
the DOT&PF's request and below in this proposed IHA, which include
maintaining a minimum distance of 100 m (328 ft) from all sea otters.
Additional information on vessel activities can be found in the
supplemental information to this document (available as described above
in ADDRESSES).
Effects on Sea Otter Habitat and Prey
Information on the potential impacts of the specified activities on
sea otter habitat and prey species can be found in the supplemental
information to this document (available as described above in
ADDRESSES). Based on this information, we do not anticipate any
harassment to sea otters due to effects on sea otter habitat or prey
from the specified activities.
Potential Impacts of the Specified Activities on Subsistence Uses
The specified activities will occur near marine subsistence harvest
areas used by Alaska Natives from Angoon and the surrounding areas. The
majority of sea otter harvest in this area occurs more than 51
kilometers (km) (31 miles [mi]) outside of Angoon. Since 2015, there
have been 6 sea otters harvested in the Angoon area, and all 6 sea
otters were harvested in 2018. From 2019 through 2024, there have been
no sea otters harvested from the Angoon area.
The planned project will occur within the Angoon city limits, where
firearm use is prohibited. The area potentially affected by the planned
project does not significantly overlap with current subsistence harvest
areas. Construction activities will not preclude access to hunting
areas or interfere in any way with individuals wishing to hunt. Despite
no conflict with subsistence use being anticipated, the FWS will
conduct outreach with potentially affected communities to see whether
there are any questions, concerns, or potential conflicts regarding
subsistence use in those areas. If any conflicts are identified in the
future, the DOT&PF will develop a plan of cooperation (POC) specifying
the steps necessary to minimize any effects the project may have on
subsistence harvest.
Estimated Take
Definitions of Incidental Take Under the MMPA
Under the MMPA, ``take'' means ``to harass, hunt, capture, or kill,
or attempt to harass, hunt, capture, or kill any marine mammal'' (16
U.S.C. 1362(13)). Below we provide definitions of three types of take
of sea otters. The FWS does not anticipate and is not proposing to
authorize lethal take as a part of this proposed IHA; however, the
definitions of these take types are provided for context and
background.
Lethal Take
In the most serious interactions, human actions can result in the
mortality of sea otters, which we define here as lethal take.
Level A Harassment
The MMPA defines Level A harassment, for nonmilitary readiness
activities, as ``any act of pursuit, torment, or annoyance which . . .
has the potential to injure a marine mammal or marine mammal stock in
the wild'' (16 U.S.C. 1362(18)(A)(i), (C)). We interpret this
definition to include human activity that may result in injury to sea
otters.
Level B Harassment
The MMPA defines Level B harassment for nonmilitary readiness
activities as ``any act of pursuit, torment, or annoyance which . . .
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, feeding, or sheltering''
(16 U.S.C. 1362(18)(A)(ii), (D)). We interpret this definition to
include human-caused reactions that disrupt biologically significant
behaviors or activities for the affected animal. Such reactions
include, but are not limited to, the following:
<bullet> Swimming away at a fast pace on belly (i.e., porpoising);
<bullet> Repeatedly raising the head vertically above the water to
get a better view (spyhopping) while apparently agitated or while
swimming away;
<bullet> In the case of a pup, repeatedly spyhopping while hiding
behind and holding onto its mother's head;
<bullet> Abandoning prey or feeding area;
<bullet> Ceasing to nurse and/or rest (applies to dependent pups);
<bullet> Ceasing to rest (applies to independent animals);
<bullet> Ceasing to use movement corridors;
<bullet> Ceasing mating behaviors;
<bullet> Shifting/jostling/agitation in a raft (i.e., group of 10
or more sea otters) so that the raft disperses;
[[Page 14574]]
<bullet> Sudden diving of an entire raft; or
<bullet> Flushing animals off a haulout.
This list does not encompass all possible behaviors that indicate
Level B harassment; other behavioral responses may be indicative of
take by Level B harassment. In some circumstances, eliciting behavioral
responses that equate to take by Level B harassment repeatedly may
result in Level A harassment. Relatively minor changes in behavior such
as the animal raising its head or temporarily changing its direction of
travel are not likely to disrupt biologically important behavioral
patterns, and the FWS does not view such minor changes in behavior as
indicative of a take by Level B harassment.
Calculating Take
Sea Otter Density
We assumed all sea otters exposed to underwater sound levels that
meet the acoustic exposure criteria defined above in Exposure
Thresholds would experience take by Level A harassment or Level B
harassment. We refer to the area in which sound levels meet or exceed
the acoustic exposure criteria defined for either Level A harassment or
Level B harassment as the ensonification area. Spatially explicit
ensonification areas were established around the planned construction
location to estimate the number of sea otters that may be exposed to
these sound levels.
Recent estimates of the number of sea otters in the project area
are less than 1 sea otter/square kilometer (km\2\). Tinker et al.
(2019) estimated an average of 0.237 sea otters/km\2\ in the subregion
N10, which is closest to the project area. Ecological diffusion models
have also been used to examine sea otter distribution in the region at
a finer scale, and these models have estimated the posterior mean and
95 percent posterior quantiles for sea otter density within the project
area (Eisaguirre et al. 2021, 2023; Schuette et al. 2023). The upper 95
percent posterior quantile for sea otter density, which is a
conservative density estimate, ranged from 0.025 to 0.213 sea otters/
km\2\ inside the project's largest ensonification area within Killisnoo
Harbor (Eisaguirre et al. 2021, 2023; Schuette et al. 2023). We used
the greatest estimated sea otter density of 0.213 sea otters/km\2\ in
our analysis to estimate the number of sea otters potentially affected
by the project activities.
Sound Levels for the Specified Activities
The project activities consist of multiple possible methods of pile
removal (vibratory pile extraction, direct-pull methods, and use of an
exothermic cutting torch to cut steel cable anchors) and multiple pile
installation methods (vibratory pile driving, impact pile driving, and
DTH drilling of rock sockets and tension anchors). Each method
generates a different type of in-water noise. Vibratory pile extraction
and installation will produce nonimpulsive noise; impact pile
installation will produce impulsive noise; and DTH drilling of rock
sockets and tension anchors is considered to produce both impulsive and
nonimpulsive noise (NMFS 2020).
The level of sound anticipated from each project component was
established using recorded data from several sources in addition to
guidance from NMFS. We used the empirical data from those proxy
projects and sound levels provided by NMFS with the NMFS Technical
Guidance and User Spreadsheet (NMFS 2018, 2020) to determine the
distance at which sound levels would attenuate to Level A harassment
thresholds (table 2 above). To estimate the distances at which sounds
would attenuate to Level B harassment thresholds (table 2 above), we
used the data from the proxy projects and the sound levels provided by
NMFS with the NMFS-recommended transmission loss coefficient of 15 for
coastal pile-driving activities in a practical spreading loss model
(NMFS 2020) to determine the distance at which sound levels attenuate
to 160 dB re 1 micropascal ([mu]Pa). The weighting factor adjustment
included in the NMFS user spreadsheet accounts for sounds experienced
in less sensitive portions of an animal's hearing range. We used the
weighting factor adjustment for otariid pinnipeds as they are the
closest available physiological and anatomical proxy for sea otters. We
acknowledge that NMFS has revised their user spreadsheet to include
thresholds for auditory injury (NMFS 2024). We are evaluating the
auditory injury criteria to determine whether they are appropriate for
FWS trust species, as sea otters in particular are not exposed to in-
water noise for an entire 24-hour period. We will continue to use the
previous version of the user spreadsheet (NMFS 2018) to estimate
harassment of sea otters from in-water noise exposure during our
evaluation of the auditory injury criteria.
Sound levels for all sources are unweighted and given in dB re 1
[mu]Pa. For nonimpulsive sound sources, sound levels are shown in the
form of mean maximum root mean square (RMS) SPL. For impulsive sound
sources, sound levels are shown in the forms of peak sound level and
sound exposure level for a single strike (SELss). Sound levels for
project activities are listed in table 3 below.
Table 3--DOT&PF Angoon Ferry Terminal Sound Types, Levels, and Timing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Timing per pile
(nonimpulsive
Pile size and sound sources) or
Project component material Activity Type of sound Sound levels Source strikes per pile
(impulsive sound
sources)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Demolition..................... 50.8-cm (20-in) Removal--vibratory Nonimpulsive........ 163 dB RMS........ NMFS 2023......... 15 minutes.
steel.
61.0-cm (24-in) Removal--vibratory Nonimpulsive........ 163 dB RMS........ NMFS 2023......... 15 minutes.
steel.
Construction................... 61.0-cm (24-in) Temporary Nonimpulsive........ 163 dB RMS........ NMFS 2023......... 15 minutes.
steel. installation--vib
ratory.
Temporary removal-- 163 dB RMS........ NMFS 2023......... 15 minutes.
vibratory.
50.8-cm (20-in) Installation--vibr Nonimpulsive........ 163 dB RMS........ NMFS 2023......... 15 minutes.
steel. atory. Impulsive........... 190 dB RMS; 177 dB Caltrans 2015..... 50 strikes.
Installation--impa SELss; 203 dB
ct. peak.
Installation--tens Impulsive and 156 dB RMS; 144 dB Reyff & Heyvaert 240 minutes/
ion anchor DTH. nonimpulsive. SELss; 170 dB 2019; Reyff 2020; 144,000 strikes.
peak. NMFS 2022.
[[Page 14575]]
61.0-cm (24-in) Installation--vibr Nonimpulsive........ 163 dB RMS........ NMFS 2023......... 15 minutes.
steel. atory. Impulsive........... 190 dB RMS; 177 dB Caltrans 2015..... 50 strikes.
Installation--impa SELss; 203 dB
ct. peak.
Installation--tens Impulsive and 156 dB RMS; 144 dB Reyff & Heyvaert 240 minutes/
ion anchor DTH. nonimpulsive. SELss; 170 dB 2019; Reyff 2020; 144,000 strikes.
peak. NMFS 2022.
76.2-cm (30-in) Installation--vibr Nonimpulsive........ 166 dB RMS........ NMFS 2023......... 15 minutes.
steel. atory. Impulsive........... 190 dB RMS; 177 dB Caltrans 2015..... 50 strikes.
Installation--impa SELss; 210 dB
ct. peak.
Installation--tens Impulsive and 156 dB RMS; 144 dB Reyff & Heyvaert 240 minutes/
ion anchor DTH. nonimpulsive. SELss; 170 dB 2019; Reyff 2020; 144,000 strikes.
peak. NMFS 2022.
Installation--rock 174 dB RMS; 164 dB Denes et al. 2019; 480 minutes/
socket DTH. SELss; 194 dB Reyff & Heyvaert 288,000 strikes.
peak. 2019; Reyff 2020;
NMFS 2022.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Ensonified Areas
Distances to below Level A harassment and Level B harassment
thresholds were calculated for each project activity to determine the
ensonified area for a given project activity. The DOT&PF would
implement a 10-m (33-ft) physical interaction shutdown zone, regardless
of predicted sound levels, to minimize the potential for physical
impacts to sea otters. Additionally, this 10-m (33-ft) physical
interaction shutdown zone would reduce the number of sea otters exposed
to in-water noise levels at or above Level A harassment and Level B
harassment thresholds. The 10-m (33-ft) physical interaction shutdown
zone would encompass the majority of the Level A harassment zones and
some of the Level B harassment zones (table 4 below).
Table 4--DOT&PF Angoon Ferry Terminal Distances to Below Level A Harassment and Level B Harassment Zones and
Proposed Physical Interaction Shutdown Zones
----------------------------------------------------------------------------------------------------------------
Distance to Distance to Distance to
below Level below Level below
Pile size and A B physical
Project component material Activity harassment harassment interaction
threshold threshold shutdown
(m) (m) zone (m)
----------------------------------------------------------------------------------------------------------------
Demolition...................... 50.8-cm (20-in) Removal--vibratory 0.4 15.8 10.0
steel.
61.0-cm (24-in) Removal--vibratory 0.4 15.8 10.0
steel.
Construction.................... 61.0-cm (24-in) Temporary 0.4 15.8 10.0
steel. installation--vib
ratory.
Temporary removal-- 0.4 15.8 10.0
vibratory.
50.8-cm (20-in) Installation--vibr 0.4 15.8 10.0
steel. atory.
Installation--impa 5.3 1,000.0 10.0
ct.
Installation--tens 4.3 5.4 10.0
ion anchor DTH.
61.0-cm (24-in) Installation--vibr 0.4 15.8 10.0
steel. atory.
Installation--impa 5.3 1,000.0 10.0
ct.
Installation--tens 4.3 5.4 10.0
ion anchor DTH.
76.2-cm (30-in) Installation--vibr 0.6 25.1 10.0
steel. atory.
Installation--impa 5.3 1,000.0 10.0
ct.
Installation--tens 4.3 5.4 10.0
ion anchor DTH.
Installation--rock 91.8 85.8 10.0
socket DTH.
----------------------------------------------------------------------------------------------------------------
We calculated the area ensonified to >232 dB peak SPL or >203 dB
SEL<INF>CUM</INF> re 1[mu]Pa for impulsive underwater sound and >219 dB
SEL<INF>CUM</INF> re 1[mu]Pa for nonimpulsive underwater sound to
determine the area in which sea otters may experience Level A
harassment during the DOT&PF's project activities. Next, we multiplied
the ensonified area for Level A harassment by the density of sea otters
for the project area (see Sea Otter Density) to determine the number of
sea otters that may experience Level A harassment.
To estimate the number of sea otters anticipated to experience
Level B harassment during the DOT&PF's project activities, we
subtracted the area of the Level A harassment zone from the area
ensonified to >160 dB re 1[mu]Pa to determine the area in which sea
otters may experience Level B harassment. Next, we multiplied the
remaining ensonified area for Level B harassment by the density of sea
otters for the project area (see Sea Otter Density) to determine the
number of sea otters that may experience Level B harassment. The DOT&PF
provided geospatial files representing the area where pile driving and
construction will occur and the ensonified water around the
construction area. These geospatial files were clipped by land
boundaries; therefore, only the area of ensonified water was provided
by the applicant.
[[Page 14576]]
The number of sea otters expected to be exposed to such noise levels
that would attenuate to Level A harassment and Level B harassment
thresholds during project activities can be found in tables 5 and 6
below, respectively.
Table 5--DOT&PF Angoon Ferry Terminal Level A Harassment Events Anticipated
--------------------------------------------------------------------------------------------------------------------------------------------------------
Estimated Total Total
Maximum sea otters estimated estimated
Pile size and number of Sea otter Level A affected by Level A Level A
Project component material Activity days of density area Level A harassment harassment
activity (km\2\) sound per events events
day (unrounded) (rounded)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Demolition...................... 50.8-cm (20-in) Removal--vibratory 2 0.213 sea otters/ <0.001 <0.001 <0.001 * 0
steel. km\2\.
61.0-cm (24-in) Removal--vibratory 1 <0.001 <0.001 <0.001 * 0
steel.
Construction.................... 61.0-cm (24-in) Temporary 16 <0.001 <0.001 <0.001 * 0
steel. installation--vib
ratory.
Temporary removal-- 16 <0.001 <0.001 <0.001 * 0
vibratory.
50.8-cm (20-in) Installation--vibr 2 <0.001 <0.001 <0.001 * 0
steel. atory.
Installation--impa 4 0.001 <0.001 <0.001 * 0
ct.
Installation--tens 7 <0.001 <0.001 0.001 \a\ 2
ion anchor DTH.
61.0-cm (24-in) Installation--vibr 5 <0.001 <0.001 <0.001 * 0
steel. atory.
Installation--impa 10 0.001 <0.001 0.002 \a\ 2
ct.
Installation--tens 16 <0.001 <0.001 0.003 \a\ 2
ion anchor DTH.
76.2-cm (30-in) Installation--vibr 11 <0.001 <0.001 <0.001 * 0
steel. atory.
Installation--impa 22 0.001 <0.001 0.005 \a\ 2
ct.
Installation--tens 25 <0.001 <0.001 0.005 \a\ 2
ion anchor DTH.
Installation--rock 10 0.042 0.009 0.089 \a\ 2
socket DTH.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Where the estimated total number of exposures was 0 for 3 or more decimal places (i.e., <0.000X), the total number of exposures was assumed to be 0.
\a\ Where the estimated total number of exposures expected was greater than 0.001, we rounded to 2 instead to accommodate potential mom and pup pairs of
sea otters for project activities.
Table 6--DOT&PF Angoon Ferry Level B Harassment Events Anticipated
--------------------------------------------------------------------------------------------------------------------------------------------------------
Estimated Total Total
Maximum Level B sea otters estimated estimated
Pile size and number of Sea otter Level B area minus affected by Level B Level B
Project component material Activity days of density area Level A Level B harassment harassment
activity (km\2\) area sound per events events
(km\2\) day (unrounded) (rounded)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Demolition................... 50.8-cm (20-in) Removal--vibrat 2 0.213 sea 0.004 0.004 <0.001 0.002 \a\ 2
steel. ory. otters/km\2\.
61.0-cm (24-in) Removal--vibrat 1 0.004 0.004 <0.001 <0.001 * 0
steel. ory.
Construction................. 61.0-cm (24-in) Temporary 16 0.004 0.004 <0.001 0.012 \a\ 2
steel. installation--
vibratory.
Temporary 16 0.004 0.004 <0.001 0.012 \a\ 2
removal--vibra
tory.
50.8-cm (20-in) Installation--v 2 0.004 0.004 <0.001 0.002 \a\ 2
steel. ibratory. 4 ............. 0.852 0.851 0.181 0.726 \a\ 2
Installation--i
mpact.
Installation--t 7 0.001 <0.001 <0.001 <0.001 * 0
ension anchor
DTH.
61.0-cm (24-in) Installation--v 5 0.004 0.004 <0.001 0.004 \a\ 2
steel. ibratory. 10 ............. 0.852 0.851 0.181 1.814 2
Installation--i
mpact.
Installation--t 16 0.001 <0.001 <0.001 <0.001 * 0
ension anchor
DTH.
76.2-cm (30-in) Installation--v 11 0.007 0.007 0.001 0.015 \a\ 2
steel. ibratory. 22 ............. 0.852 0.851 0.181 3.991 4
Installation--i
mpact.
Installation--t 25 0.001 <0.001 <0.001 0.001 \a\ 2
ension anchor
DTH.
Installation--r 10 0.038 0 0 0 0
ock socket DTH.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* Where the estimated total number of exposures was 0 for 3 or more decimal places (i.e., <0.000X), the total number of exposures was assumed to be 0.
\a\ Where the estimated total number of exposures expected was greater than 0.001, we rounded to 2 instead to accommodate potential mom and pup pairs of
sea otters for project activities.
We assumed that the different types of pile-driving activities will
occur sequentially and that the total number of work days will equal
the sum of the number of days required to complete each type of pile-
driving activity. While it is possible that on some days more than one
type of activity will take place, which would reduce the number of days
of exposure, we cannot know this information in advance. As such, the
estimated number of days is the maximum possible for the planned work.
Where the estimated total number of exposures was 0 for 3 or more
decimal places (i.e., <0.000X), the total number of exposures was
assumed to be 0. Where the estimated total number of exposures expected
was greater than 0.001, we rounded up to 2 exposures to accommodate
potential mother and pup pairs of sea otters encountering project
activities.
Critical Assumptions
In order to conduct this analysis and estimate the maximum
anticipated number of takes by Level A harassment and Level B
harassment, several critical assumptions were made.
[[Page 14577]]
Sound level information from pile-driving activities in a number of
locations was used to generate sound level estimates for the specified
activities (see sources in table 3 above). Environmental conditions in
these locations, including water depth, substrate, and ambient sound
levels may be similar to those in the project location, but are not
identical. Further, ensonification area estimates were based on sound
attenuation models using a practical spreading loss model. These
factors may lead to actual sound values differing slightly from those
estimated here.
The pile-driving activities described here will also create in-air
noise. Because sea otters spend over half of their day with their heads
above water (Esslinger et al. 2014), they will be exposed to the in-air
noise produced by construction equipment. However, we have calculated
Level A harassment and Level B harassment with the assumption that a
sea otter may be harassed only one time per 24-hour period, and in-
water noise levels would be more disturbing and extend farther than in-
air noise. Thus, while sea otters may be disturbed by noise both in-air
and in-water, we have relied on the more conservative in-water
estimates.
Level B harassment is equated herein with behavioral responses that
indicate harassment or disturbance. There is likely a portion of
animals that respond in ways that indicate some level of disturbance
but do not experience biologically significant consequences. Our
estimates do not account for variable responses by sea otter age and
sex.
The behavioral response estimates presented here do not account for
the individual movements of animals in response to the specified
activities. Our assessment assumes animals remain stationary (i.e.,
density does not change) for a 24-hour period, and animals do not move
out of ensonified areas in response to noise. Not enough information is
available about the movement of sea otters in response to specific
disturbances to refine this assumption.
Although sea otters are nonmigratory, they typically move amongst
focal areas within their home ranges to rest and forage (Garshelis and
Garshelis 1984; Laidre et al. 2009). It is possible that, given the
large variability in individual home range sizes and the potential for
daily movement in and out of foraging or resting areas, different
individual sea otters could be found within the ensonification area
each day of the project. Thus, the FWS conservatively assumes that the
estimated harassment events may impact different sea otters for project
activities at the DOT&PF's project location. We estimate that 12 takes
of 12 sea otters by Level A harassment and 22 takes of 22 sea otters by
Level B harassment may occur due to the DOT&PF's planned activities.
Sea otter density was calculated using a state-space model created by
Tinker et al. (2019) and fine-scale ecological diffusion models created
by Eisaguirre et al. (2021, 2023; Schuette et al. 2023). Methods and
assumptions for these surveys can be found in the original
publications.
Sum of Harassment From All Sources
The DOT&PF will conduct pile driving and marine construction
activities in Angoon between May 1, 2026 and April 30, 2027. A summary
of total estimated takes by Level A harassment and Level B harassment
during the project is provided in table 7 below.
Table 7--Sea Otters Expected To Be Harassed; Level A Harassment and Level B Harassment Events
----------------------------------------------------------------------------------------------------------------
Number of sea Total number of Number of sea Total number of
otters exposed Level A otters exposed Level B
Location to Level A harassment to Level B harassment
harassment events harassment events
----------------------------------------------------------------------------------------------------------------
Angoon (Southeast AK stock)................. 12 12 22 22
----------------------------------------------------------------------------------------------------------------
Over the course of the project, we estimate up to 12 instances of
take by Level A harassment of 12 sea otters from the Southeast Alaska
stock due to PTS associated with in-water noise exposure during project
activities. Using soft-start procedures, zone clearance prior to
activity startup, and shutdown zones is likely to decrease both the
number of sea otters exposed to noise above Level A harassment
thresholds and the exposure time of any sea otters entering the Level A
harassment zone. This reduces the likelihood of hearing sensitivity
losses that might impact the health, reproduction, or survival of
affected sea otters. Despite the implementation of mitigation measures,
it is anticipated that some sea otters may experience Level A
harassment via exposure to in-water noise above threshold criteria
during impact pile driving and DTH drilling activities.
Over the course of the project, we estimate up to 22 instances of
take by Level B harassment of 22 sea otters from the Southeast Alaska
stock due to behavioral responses to in-water noise exposure during
project activities. Although multiple instances of Level B harassment
of individual sea otters are possible, these events are unlikely to
have significant consequences for the health, reproduction, or survival
of affected sea otters. The potential effects of multiple Level B
harassment noise exposures may include short-term behavioral reactions,
displacement of sea otters near active operations, and potential
temporary shifts in hearing thresholds. We anticipate that the majority
of Level B harassment events would be behavioral responses to noise
exposure. Sea otters spend over half of their time above the surface
during the summer months (Esslinger et al. 2014), and likely no more
than 70 percent of their time foraging during winter months (Gelatt et
al. 2002); thus, their ears would not be exposed to underwater noise
for a prolonged time period, thereby reducing their likelihood to
experience temporary shifts in hearing thresholds. Also, the sound
levels from impact pile driving and DTH drilling activities will not
reach the peak SPL of instantaneous exposure likely to cause TTS
outside the 10-m (33-ft) physical interaction shutdown zone.
Considering the sound levels of the specified activities, the limited
amount of time over non-consecutive days in which the specified
activities will occur, and the localized area to be impacted by the
specified activities; we do not anticipate that the effects of multiple
Level B harassment noise exposures would rise to the level of TTS, an
injury, or Level A harassment.
Determinations and Findings
Sea otters exposed to noise from the specified activities are
likely to respond with temporary behavioral modification or
displacement. The specified activities could temporarily interrupt the
feeding, resting, and movement of sea otters. The
[[Page 14578]]
activities will occur during a limited amount of time and in a
localized area, and the impacts associated with the project are
likewise temporary and localized. The anticipated effects are short-
term behavioral reactions, displacement of sea otters near active
operations, and potential shifts in hearing thresholds.
Sea otters that encounter the specified activities may exert more
energy than they would otherwise due to temporary cessation of feeding,
increased vigilance (e.g., repeatedly spyhopping), and retreating from
the project area. We expect that affected sea otters would tolerate
this exertion without measurable effects on health or reproduction.
Most of the anticipated takes would be due to short-term Level B
harassment in the form of startling reactions, interruption of feeding,
resting, and movement, or temporary displacement. While mitigation
measures incorporated into the DOT&PF's request would reduce
occurrences of Level A harassment to the extent practicable, a small
number of takes by Level A harassment would be authorized for impact
pile driving and DTH drilling activities, which have Level A harassment
zone radii ranging up to 91.8 m (301.2 ft).
Small Numbers
For our small numbers determination, we consider whether the
estimated number of sea otters to be subjected to incidental take is
small relative to the population size of the species or stock. More
specifically, the FWS compares the number of sea otters anticipated to
be taken in the year contemplated by the proposed IHA with the
population estimate applicable for the year. Here, predicted numbers of
sea otters to be taken were determined based on the estimated density
of sea otters in the project area and ensonification areas developed
using empirical evidence from similar geographic areas. We estimate
that the DOT&PF's specified activities in the specified geographic
region would take no more than 34 Southeast Alaska stock northern sea
otters by Level A harassment and Level B harassment during the 1-year
period of this proposed IHA (see Sum of Harassment from All Sources).
Take of 34 sea otters is 0.15 percent of the best available estimate of
the current annual Southeast Alaska stock size of 22,359 animals
(Schuette et al. 2023; 88 FR 53510, August 8, 2023) ((34 / 22,359) x
100 [ap] 0.15), and represents a ``small number'' of sea otters of that
stock.
Further, the specified activity area is small relative to the range
of the Southeast Alaska stock of sea otters. The Southeast Alaska stock
of sea otters ranges well beyond the nearshore waters surrounding the
Angoon Ferry Terminal located within Killisnoo Harbor, meaning this
specified geographic region represents only a small subset of the
potential area in which this population may occur.
Therefore, we propose a finding that the DOT&PF's specified
activities would take only small numbers of sea otters because: (1)
only a small proportion of sea otters would overlap with the areas
where the specified activities will occur; and (2) the estimated number
of Southeast Alaska stock sea otters to be taken would be limited to a
total of 34 sea otters over the duration of the proposed IHA, which
represents a small proportion (0.15 percent) of the stock of sea
otters.
Negligible Impact
We propose a finding that any incidental take by harassment
resulting from the specified activities cannot be reasonably expected
to, and is not reasonably likely to, adversely affect the sea otter
through effects on annual rates of recruitment or survival and would,
therefore, have no more than a negligible impact on the Southeast
Alaska stock of sea otters. In making this finding, we considered the
best available scientific information including the biological and
behavioral characteristics of the species, the most recent information
on species distribution and abundance within the specified activity
area, the current and expected future status of the stock (including
existing and foreseeable human and natural stressors), the potential
disturbance sources caused by the specified activities, and the
potential marine mammals responses to this disturbance. In addition, we
reviewed applicant-provided materials, our own files and datasets,
published reference materials, and input from species experts.
The specified activities may impact sea otters by causing short-
term behavioral reactions, by displacing sea otters near active
operations, and by potentially causing hearing threshold shifts. While
Level A harassment has the potential to result in the injury (hearing
threshold shift) of up to 12 sea otters during the IHA period, this
type of harassment is not anticipated to result in long-term impacts
that are likely to result in mortality. Most sea otters would respond
to disturbance by moving away from the source, which may cause
temporary interruption of foraging, resting, or other natural
behaviors. Affected sea otters are expected to resume normal behaviors
soon after exposure with no lasting consequences to their survival or
reproduction. Sea otters may move in and out of the project area during
pile-driving activities, leading to as many as 34 sea otters
experiencing exposure to noise at levels that may cause harassment.
However, it is possible that a sea otter may enter the ensonification
area more than once during the project. At most, if the same sea otter
enters the ensonification area every day that pile driving occurs, the
sea otter would be exposed to pile driving and marine construction
noise for up to 147 non-consecutive days.
It is possible that sea otters may be exposed to noise levels equal
to or greater than Level A harassment thresholds on multiple days
throughout project activities. The potential effects of multiple Level
A harassment noise exposures may include a greater reduction in a sea
otter's hearing sensitivity, but this reduction in hearing sensitivity
does not equate to total hearing loss. The reduction in sea otter
hearing sensitivity caused by PTS would align with the energy produced
by pile-driving activities (e.g., low-frequency less than 2 kHz), which
would not impair the majority of a sea otter's hearing range. Sea
otters do not rely on sound to orient themselves, locate prey, or
communicate under water. Therefore, we do not anticipate PTS from
multiple Level A harassment noise exposures would impact sea otters'
ability to move, forage, or communicate. Sea otters, especially mothers
and pups, do use sound for communication in air (McShane et al. 1995),
and sea otters may monitor underwater sound to avoid predators (Davis
et al. 1987). However, we anticipate that a sea otter would retain the
majority of its hearing range if it experiences PTS from multiple Level
A harassment noise exposures and that impacts from PTS would not have
long-term consequences to a sea otter's survival and reproduction.
It is possible that sea otters would move away from Level A
harassment zones and avoid experiencing PTS. The area that will
experience noise levels equal to or greater than Level A harassment
thresholds due to pile driving is small (~0.04 km\2\), and a sea otter
that may be disturbed could escape the noise by moving to nearby
quieter areas. Further, sea otters spend over half of their time above
the surface during the summer months (Esslinger et al. 2014), and
likely no more than 70 percent of their time foraging during winter
months (Gelatt et al. 2002); thus, their ears would not be exposed to
underwater noise for a prolonged time
[[Page 14579]]
period, thereby reducing their likelihood of experiencing PTS. Some sea
otters may exhibit some of the stronger responses typical of Level B
harassment, such as fleeing, interruption of feeding, or flushing from
a haulout. These responses could have temporary biological impacts for
affected sea otters but are not anticipated to result in measurable
changes in survival or reproduction. Therefore, we anticipate the
specified activities would not have lasting impacts that could
significantly affect an individual's health, reproduction, or survival.
The anticipated impacts on sea otters are limited and therefore
unlikely to adversely affect annual rates of sea otter survival or
recruitment.
The total number of sea otters affected and the impact severity are
not sufficient to change the current population dynamics at the stock
scale. Although the specified activities may result in a maximum of 34
incidental takes of up to 34 sea otters from the Southeast Alaska
stock, we do not expect this level of harassment to affect annual rates
of recruitment or survival or result in adverse effects on the stock.
Our proposed finding of negligible impact applies to incidental
take associated with the specified activities as mitigated by the
avoidance and minimization measures identified in the DOT&PF's
mitigation and monitoring plan. These mitigation measures are designed
to minimize interactions with and impacts to sea otters. These measures
and the monitoring and reporting procedures are required for the
validity of our finding and are a necessary component of the proposed
IHA. For these reasons, we propose a finding that the specified project
would have a negligible impact on the Southeast Alaska stock of sea
otters.
Least Practicable Adverse Impact
We propose a finding that the mitigation measures required by this
proposed IHA would effect the least practicable adverse impact on the
Southeast Alaska stock of sea otters from any incidental take likely to
occur in association with the specified activities. In making this
finding, we considered the biological characteristics of sea otters,
the nature of the specified activities, the potential effects of the
activities on sea otters, the documented impacts of similar activities
on sea otters, and alternative mitigation measures. After reviewing the
original request (submitted November 13, 2024), the FWS discussed
additional mitigation measures with the DOT&PF to reduce potential
impacts of the specified activities. These additional mitigation
measures included maintaining a minimum avoidance distance between sea
otters and vessels supporting the project activities and revising sea
otter monitoring zones, shutdown zones, and shutdown periods. The
applicant incorporated these additional mitigation measures in their
revised request and supporting documentation.
In evaluating what mitigation measures are appropriate to ensure
the least practicable adverse impact on species or stocks and their
habitat, as well as subsistence uses, we considered the manner and
degree to which the successful implementation of the measures is
expected to achieve this goal. We considered the nature of the
potential adverse impact being mitigated (likelihood, scope, range),
the likelihood that the measures would be effective if implemented, and
the likelihood of effective implementation. We also considered the
practicability of the measures for applicant implementation (e.g.,
cost, impact on operations).
To reduce the potential for disturbance associated with the
activities, the DOT&PF would implement mitigation measures, including
the following:
<bullet> Using the smallest diameter piles practicable while
minimizing the overall number of piles;
<bullet> Using a project design that does not include dredging or
blasting;
<bullet> Minimizing the use of the impact hammer to the extent
possible by using a vibratory hammer to advance piles as deeply as
possible;
<bullet> Development of a marine mammal monitoring and mitigation
plan;
<bullet> Visual mitigation monitoring by designated protected
species observers (PSOs);
<bullet> Halting or delaying activity during environmental
conditions that may hinder sea otter detection, such as darkness,
adverse weather conditions, high sea states, and other times of limited
visibility;
<bullet> Maintaining the maximum distance practicable between a
vessel and raft of sea otters;
<bullet> Operating vessels in such a way as to avoid approaching
sea otters or impeding sea otter movements when traveling near the
shoreline in shallow water (<20 m [66 ft]) whenever practicable;
<bullet> Establishment of shutdown and monitoring zones;
<bullet> Site clearance before activity startup;
<bullet> Soft-start procedures; and
<bullet> Shutdown procedures.
A number of additional potential mitigation measures were
considered but determined to be not practicable and/or not effective.
These measures are listed below:
<bullet> Require use of bubble curtains and other noise-dampening
methods--The applicant indicated that implementation of bubble curtains
and other noise-dampening methods such as cofferdams, pile-surrounding
casings, sound mitigation screens, and nets around piles are costly and
difficult to install and would have to be designed and constructed
specifically for the project. The FWS determined the required use of
bubble curtains and other noise-dampening methods was not practicable
because these mitigation measures were unduly burdensome to undertake
for the project activities.
<bullet> Require pile-driving activities be conducted at lower
tidal heights--The applicant indicated that conducting pile-driving
activities at lower tidal heights to reduce transmission of sound into
the water column would add delays to the project schedule and impact
the ferry service for the community. The FWS determined that requiring
pile-driving activities to be conducted at lower tidal heights was not
practicable because this mitigation measure was unduly burdensome to
undertake for the project activities.
<bullet> Require use of alternate detection methods--The FWS
determined that the required use of alternate detection methods such as
infrared sensors; thermal imaging; or surveys conducted by aircraft,
unmanned aircraft system (UAS), or vessel was not practicable
considering that these alternate detection methods would be less
effective than PSOs in reducing impacts to sea otters due to the
limited number of project activities and small spatial extent of
ensonified areas. The applicant would employ PSOs to monitor the
project area for sea otters to reduce impacts to sea otters.
Impact on Subsistence Use
The anticipated harassment will not preclude access to harvest
areas or interfere with the availability of sea otters for harvest by
Alaska Native Peoples. Additionally, the existing ferry terminal and
associated facilities are located within the City of Angoon, where
firearm use is prohibited. We therefore propose a finding that the
DOT&PF's anticipated harassment would not have an unmitigable adverse
impact on the availability of any stock of sea otters for taking for
subsistence uses by Alaska Native Peoples during the specified
timeframe. In making this proposed finding, we considered the
[[Page 14580]]
timing and location of the planned activities and the timing and
location of subsistence harvest activities in the project area.
The harvest of sea otters is important to Alaska Native people in
the communities surrounding Angoon. The DOT&PF would be required to
contact subsistence communities that may be affected by the pile
driving and marine construction activities to discuss potential
conflicts caused by location, timing, and methods of the specified
activities. The DOT&PF must make reasonable efforts to ensure that
activities do not interfere with subsistence hunting and that adverse
effects on the availability of sea otters are minimized. No concerns
have been voiced by the Alaska Native communities regarding the
specified activities limiting availability of sea otters for
subsistence uses. However, should such a concern be voiced, a POC,
which identifies measures to minimize any adverse effects, would be
implemented. The POC would ensure that the DOT&PF would not have an
unmitigable adverse impact on the availability of the species or stock
for subsistence uses. This POC would provide the procedures addressing
how the DOT&PF would work with the affected Alaska Native communities
and what actions would be taken to avoid interference with subsistence
hunting of sea otters, as warranted.
The FWS has not received any reports and is not aware of
information that indicates that sea otters are being or would be
deterred from hunting areas or impacted in any way that diminishes
their availability for subsistence use by the expected level of pile
driving and marine construction activity. If there is evidence that
these pile driving and marine construction activities are affecting the
availability of sea otters for subsistence uses, we would reevaluate
our findings regarding permissible limits of take and the measures
required to ensure continued subsistence hunting opportunities.
Monitoring and Reporting
The purpose of monitoring requirements is to assess the effects of
specified activities on sea otters; to ensure that take is consistent
with that anticipated in the small numbers, negligible impact, and
subsistence use analyses; and to detect any unanticipated effects on
the species or stock. Monitoring plans document when and how sea otters
are observed, the number of sea otters, and their behaviors during the
observation. This information allows the FWS to measure encounter
rates, examine trends in sea otter activity and distribution in the
project area, and estimate the number of sea otters potentially
affected by the specified activities. The DOT&PF is required to report
all observations of sea otters. To the extent possible, PSOs would
record group size, age, sex, behavior, duration of observation, and
closest approach to the project activity.
As proposed, monitoring activities would be summarized and reported
in formal reports. The DOT&PF must submit monthly reports for all
months during which noise-generating work takes place as well as a
final monitoring report that must be submitted no later than 90 days
after the expiration of the IHA. We would require approval of the
monitoring results for continued operation under the IHA.
We find that these proposed monitoring and reporting requirements
to evaluate the potential impacts of planned activities would ensure
that the effects of the activities remain consistent with the rest of
the findings.
References Cited
A list of the references cited in this notice may be found at
<a href="https://www.regulations.gov">https://www.regulations.gov</a> under Docket No. FWS-R7-ES-2025-1232.
Required Determinations
National Environmental Policy Act (NEPA)
We have prepared a draft environmental assessment in accordance
with NEPA (42 U.S.C. 4321 et seq.). We have preliminarily concluded
that the proposed action of issuing a final IHA would not significantly
affect the quality of the human environment and, thus, preparation of
an environmental impact statement for this IHA, if finalized, is not
required by section 102(2) of NEPA or its implementing regulations. We
are accepting comments on the draft environmental assessment as
specified above in DATES and ADDRESSES.
Endangered Species Act (ESA)
Under the ESA (16 U.S.C. 1536(a)(2)), all Federal agencies are
required to ensure the actions they authorize are not likely to
jeopardize the continued existence of any threatened or endangered
species or result in destruction or adverse modification of critical
habitat. The specified activities will occur entirely within the range
of the Southeast Alaska stock of sea otters, which is not listed as
threatened or endangered under the ESA. The authorization of incidental
take of sea otters and the measures included in the proposed IHA would
not affect other listed species or designated critical habitat.
Government-to-Government Consultation
It is our responsibility to communicate and work directly on a
Government-to-Government basis with federally recognized Alaska Native
Tribes and organizations in developing programs for healthy ecosystems.
We seek their full and meaningful participation in evaluating and
addressing conservation concerns for protected species. It is our goal
to remain sensitive to Alaska Native culture, and to make information
available to Alaska Natives. Our efforts are guided by the following
policies and directives:
(1) The Native American Policy of the Service (January 20, 2016);
(2) The Alaska Native Relations Policy (currently in draft form);
(3) Executive Order 13175 (January 9, 2000);
(4) Department of the Interior Secretarial Orders 3206 (June 5,
1997), 3225 (January 19, 2001), 3317 (December 1, 2011), 3342 (October
21, 2016), and 3403 (November 15, 2021), including Director's Order 227
(September 8, 2022);
(5) the Alaska Government-to-Government Policy (a departmental
memorandum issued January 18, 2001); and
(6) the Department of the Interior's policies on consultation with
Alaska Native Tribes and organizations.
We have evaluated possible effects of the specified activities on
federally recognized Alaska Native Tribes and organizations. Through
the IHA process identified in the MMPA, the applicant has presented a
communication process, culminating in a POC if needed, with the Alaska
Native organizations and communities most likely to be affected by
their work. The FWS does not anticipate impacts to Alaska Native Tribes
or Alaska Native Claims Settlement Act corporations and does not
anticipate requesting consultation; however, we invite continued
discussion, either about the project and its impacts or about our
coordination and information exchange throughout the IHA/POC process.
Paperwork Reduction Act
This authorization does not contain any new collection of
information that requires approval by the Office of Management and
Budget (OMB) under the Paperwork Reduction Act of 1995 (44 U.S.C. 3501
et seq.). The OMB has previously approved the information collection
requirements associated with
[[Page 14581]]
IHAs and assigned OMB Control Number 1018-0194 (expires August 31,
2026). An agency may not conduct or sponsor, and a person is not
required to respond to, a collection of information unless it displays
a currently valid OMB control number.
Proposed Authorization
We propose to authorize the nonlethal, incidental take by Level A
harassment and Level B harassment of up to 34 sea otters from the
Southeast Alaska stock. Authorized take would be limited to disruption
of behavioral patterns, displacement of sea otters near active
operations, or hearing threshold shifts that may be caused by pile
driving and marine construction activities conducted by the DOT&PF in
Angoon, Alaska, between May 1, 2026, and April 30, 2027. We do not
anticipate or propose to authorize any lethal take to sea otters
resulting from these activities.
A. General Conditions for This IHA
(1) Activities must be conducted in the manner described in the
revised request dated May 8, 2025, from the DOT&PF for an IHA and in
accordance with all applicable conditions and mitigations measures. The
taking of sea otters whenever the required conditions, mitigation,
monitoring, and reporting measures are not fully implemented as
required by the IHA is prohibited. Failure to follow the measures
specified both in the revised request and within this proposed
authorization may result in the modification, suspension, or revocation
of the IHA.
(2) If project activities cause unauthorized take (i.e., greater
than 34 takes of the Southeast Alaska stock of sea otters, a form of
take other than Level A harassment or Level B harassment, or take of
one or more sea otters through methods not described in the IHA), the
DOT&PF must take the following actions:
(i) Cease its activities immediately (or reduce activities to the
minimum level necessary to maintain safety);
(ii) Report the details of the incident to the FWS within 24 hours;
and
(iii) Suspend further activities until the FWS has reviewed the
circumstances and determined whether additional mitigation measures are
necessary to avoid further unauthorized taking.
(3) All operation managers, vehicle operators, and machine
operators must receive a copy of this IHA and maintain access to it for
reference at all times during project work. These personnel must
understand, be fully aware of, and be capable of implementing the
conditions of the IHA at all times during project work.
(4) This IHA will apply to activities associated with the specified
project as described in this document and in the DOT&PF's revised
request. Changes to the specified project without prior authorization
may invalidate the IHA.
(5) The DOT&PF's revised request is approved and fully incorporated
into this IHA unless exceptions are specifically noted herein. The
request includes:
(i) The DOT&PF's original request for an IHA, dated November 13,
2024;
(ii) A revised application, dated November 26, 2024;
(iii) Project geospatial files for ensonification areas, received
March 24, 2025;
(iv) A revised application, dated May 8, 2025; and
(v) Protected Species Monitoring and Mitigation Plan, dated May 8,
2025.
(6) Operators will allow the FWS personnel or the FWS's designated
representative to visit project worksites to monitor for impacts to sea
otters and subsistence uses of sea otters at any time throughout
project activities so long as it is safe to do so. ``Operators'' are
all personnel operating under the DOT&PF's authority, including all
contractors and subcontractors.
B. Avoidance and Minimization
(7) Construction activities must be conducted using equipment that
generates the lowest practicable levels of in-water noise within the
range of frequencies audible to sea otters.
(8) If a sea otter enters or appears likely to enter the shutdown
zone, in-water activities must be shut down until either the sea otter
has been visually observed outside the shutdown zone or at least 15
minutes have elapsed since the last observation time without
redetection of the sea otter.
(i) During all in-water activities, regardless of predicted sound
levels, a physical interaction shutdown zone of at least 10 m (33 ft)
must be enforced.
(9) If the impact driver has been idled for more than 30 minutes,
an initial set of three strikes from the impact driver must be
delivered (at reduced energy if possible), followed by a 30-second
waiting period. This procedure will be conducted a total of three times
before full-powered strikes if practicable.
(10) In-water activity must be conducted in daylight. If
environmental conditions prevent visual detection of sea otters within
the shutdown zone, in-water activities must be stopped until visibility
is regained.
C. Mitigation Measures for Vessel Operations
Vessel operators must take every precaution to avoid harassment of
sea otters during vessel operations. The applicant must carry out the
following measures:
(11) Vessels must maintain a minimum distance of 500 m (0.3 mi)
from rafts of 10 or more sea otters unless otherwise needed for safety.
If a vessel must transit within 500 m (0.3 mi) from rafts of sea
otters, the vessel must travel at a reduced speed and maintain the
maximum distance practicable between the vessel and raft of sea otters.
Vessels must reduce speed and maintain a minimum distance of 100 m (328
ft) from all sea otters unless otherwise needed for safety.
(12) Vessels must not be operated in such a way as to separate
members of a group of sea otters (two or more sea otters) from other
members of the group, encircle sea otters, or impede movement of sea
otters. Vessels must use established navigation channels or commonly
recognized vessel traffic corridors and avoid approaching sea otters or
impeding sea otter movements when traveling near the shoreline in
shallow water (<20 m or <66 ft) whenever practicable.
(13) When weather conditions require, such as when visibility
drops, vessels must adjust speed accordingly to reduce the likelihood
of injury to sea otters.
(14) Vessel operators must be provided written guidance for
avoiding collisions and minimizing disturbances to sea otters. Guidance
will include all measures identified in this section.
D. Monitoring
(15) Operators shall work with PSOs to apply mitigation measures
and shall recognize the authority of PSOs up to and including stopping
work, except in situations where doing so poses a significant safety
risk to personnel.
(16) Duties of the PSOs include watching for and identifying sea
otters, recording observation details, documenting presence in any
applicable monitoring zone, identifying and documenting potential
harassment, and working with operators to implement all appropriate
mitigation measures.
(17) A sufficient number of PSOs will be available to meet the
following criteria: 100 percent monitoring of shutdown zones during all
daytime periods of in-water noise-generating work; a maximum of 4
consecutive hours on watch per PSO; a maximum of 12 hours on watch per
day per PSO.
(18) All PSOs will complete a training course designed to
familiarize
[[Page 14582]]
individuals with monitoring and data collection procedures. This
training will be completed prior to starting work. A field crew leader
with prior experience as a sea otter observer will supervise the PSO
team. Initially, new or inexperienced PSOs will be paired with
experienced PSOs so that the quality of marine mammal observations and
data recording is kept consistent. Resumes for candidate PSOs will be
made available to the FWS prior to the start of the project.
(19) The PSOs will be provided with reticule binoculars (7x50 or
better), big-eye binoculars or spotting scopes (30x), inclinometers,
and range finders. Field guides, instructional handbooks, maps, and a
contact list will also be made available.
(20) The PSOs will monitor a pre-clearance zone for 30 minutes
prior to the commencement of in-water noise-generating activities and
following periods of inactivity of more than 30 minutes to ensure no
sea otters are within the shutdown zone prior to initiating or resuming
in-water noise-generating activities.
(21) The PSOs will collect data using the following procedures:
(i) All data will be recorded onto a field form or database.
(ii) Global positioning system data, sea state, tidal state, wind
force, visibility, and weather condition will be recorded at the
beginning and end of a monitoring period; at least every hour in
between, at the change of a PSO, and upon observation of sea otters.
(iii) Observation records of sea otters will include date, time,
the PSOs' locations, sea otter's heading (if moving), weather
condition, visibility, number of sea otters, group composition (adults/
juveniles), and the location of the sea otters (or distance and
direction from the PSO).
(iv) Observation records will also include initial behaviors of the
sea otters, descriptions of project activities and in-water noise
levels being generated, the position of sea otters relative to
applicable monitoring and mitigation zones, any mitigation measures
applied, and any apparent reactions to the project activities before
and after mitigation.
(v) For all sea otters in or near a mitigation zone, the PSOs will
record the distance from the sound source to the sea otter upon initial
observation, the duration of the encounter, and the distance at last
observation in order to monitor cumulative sound exposures.
(vi) The PSOs will note any instances of sea otters lingering close
to or traveling with vessels for prolonged periods of time.
(22) Monitoring of the shutdown zone must continue for 30 minutes
following completion of in-water noise-generating activities.
E. Measures To Reduce Impacts to Subsistence Users
(23) Prior to conducting the work, the DOT&PF will take the
following steps to reduce potential effects on subsistence harvest of
sea otters:
(i) Avoid work in areas of known sea otter subsistence harvest;
(ii) Discuss the planned activities with subsistence stakeholders
including Southeast Alaska villages and traditional councils;
(iii) Identify and work to resolve concerns of stakeholders
regarding the project's effects on subsistence hunting of sea otters;
and
(iv) If any concerns remain, develop a POC in consultation with the
FWS and subsistence stakeholders to address these concerns.
F. Reporting Requirements
(24) The applicant, DOT&PF, must notify the FWS at least 48 hours
prior to commencement of activities.
(25) Monthly reports will be submitted to the FWS's Marine Mammals
Management office (MMM) for all months during which noise-generating
work takes place. The monthly report will contain and summarize the
following information: dates, times, weather, and sea conditions
(including the Beaufort Scale sea state and wind force conditions) when
sea otters were observed; the number, location, distance from the sound
source, and behavior of the sea otters; the associated project
activities; and a description of the implementation and effectiveness
of mitigation measures with a discussion of any specific behaviors the
sea otters exhibited in response to mitigation.
(26) A final report will be submitted to the FWS's MMM within 90
days after completion of work or expiration of the IHA. The report will
include:
(i) A summary of monitoring efforts (hours of monitoring,
activities monitored, number of PSOs, and, if requested by the FWS, the
daily monitoring logs).
(ii) A description of all project activities, any additional work
yet to be done, factors influencing visibility and detectability of
marine mammals (e.g., sea state, fog, glare, and number of PSOs), and
factors correlated with the presence and distribution of sea otters
(e.g., weather, sea state, and project activities).
(iii) An estimate will be included of the number of sea otters
exposed to noise at received levels greater than or equal to Level A
harassment and Level B harassment (based on visual observation).
(iv) A description of changes in sea otter behavior resulting from
project activities and any specific behaviors of interest.
(v) A discussion of the mitigation measures implemented during
project activities and their observed effectiveness for minimizing
impacts to sea otters. Sea otter observation records will be provided
to the FWS in the form of electronic database or spreadsheet files.
(27) Injured, dead, or distressed sea otters that are not
associated with project activities (e.g., animals known to be from
outside the project area, previously wounded animals, or carcasses with
moderate to advanced decomposition or scavenger damage) must be
reported to the FWS within 24 hours of the discovery to either the
FWS's MMM (907-786-3800, business hours); or the Alaska SeaLife Center
in Seward (1-888-774-7325, 24 hours a day), or both. Photographs,
video, location information, or any other available documentation must
be provided to the FWS.
(28) All reports shall be submitted by email to
<a href="/cdn-cgi/l/email-protection#751302422a1818182a0710051a070106351302065b121a03"><span class="__cf_email__" data-cfemail="4d2b3a7a12202020123f283d223f393e0d2b3a3e632a223b">[email protected]</span></a>.
(29) The DOT&PF must notify the FWS upon project completion or end
of the work season.
Request for Public Comments
If you wish to comment on this proposed authorization, the
associated draft environmental assessment, or related documents, you
may submit your comments by either of the methods described above in
ADDRESSES. Please identify the document(s) to which your comments
pertain, make your comments as specific as possible, confine them to
issues pertinent to the proposed authorization, and explain the reason
for any changes you recommend. Where possible, your comments should
reference the specific section or paragraph that you are addressing.
The FWS will consider all comments that are received before the close
of the comment period (see DATES above). The FWS does not anticipate
extending the public comment period beyond the 30 days required under
section 101(a)(5)(D)(iii) of the MMPA.
Comments, including names and street addresses of respondents, will
become part of the administrative record for this proposal. Before
including your address, telephone number, email address, or other
personal identifying information in your comment, be advised that your
entire comment,
[[Page 14583]]
including your personal identifying information, may be made publicly
available at any time. While you can ask us in your comments to
withhold from public review your personal identifying information, we
cannot guarantee that we will be able to do so.
Peter Fasbender,
Assistant Regional Director for Fisheries and Ecological Services,
Alaska Region, U.S. Fish and Wildlife Service.
[FR Doc. 2026-05744 Filed 3-24-26; 8:45 am]
BILLING CODE 4333-15-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.