[Federal Register Volume 84, Number 250 (Tuesday, December 31, 2019)]
[Notices]
[Pages 72308-72321]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-28211]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[RTID 0648-XR059]
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to Elkhorn Slough Tidal Marsh
Restoration Project, Phase II in California
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; proposed incidental harassment authorization; request
for comments on proposed authorization and possible renewal.
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SUMMARY: NMFS has received a request from California Department of Fish
and Wildlife (CDFW) for authorization to take marine mammals incidental
to Elkhorn Slough Tidal Marsh Restoration Project, Phase II in
California. Pursuant to the Marine Mammal Protection Act (MMPA), NMFS
is requesting comments on its proposal to issue an incidental
harassment authorization (IHA) to incidentally take marine mammals
during the specified activities. NMFS is also requesting comments on a
possible one-year renewal that could be issued under certain
circumstances and if all requirements are met, as described in Request
for Public Comments at the end of this notice. NMFS will consider
public comments prior to making any final decision on the issuance of
the requested MMPA authorizations and agency responses will be
summarized in the final notice of our decision.
DATES: Comments and information must be received no later than January
30, 2020.
ADDRESSES: Comments should be addressed to Jolie Harrison, Chief,
Permits and Conservation Division, Office of Protected Resources,
National Marine Fisheries Service. Physical comments should be sent to
1315 East-West Highway, Silver Spring, MD 20910 and electronic comments
should be sent to ITP. [email protected].
Instructions: NMFS is not responsible for comments sent by any
other method, to any other address or individual, or received after the
end of the comment period. Comments received electronically, including
all attachments, must not exceed a 25-megabyte file size. Attachments
to electronic comments will be accepted in Microsoft Word or Excel or
Adobe PDF file formats only. All comments received are a part of the
public record and will generally be posted online at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act without change. All personal identifying
information (e.g., name, address) voluntarily submitted by the
commenter may be publicly accessible. Do not submit confidential
business information or otherwise sensitive or protected information.
FOR FURTHER INFORMATION CONTACT: Bonnie DeJoseph, Office of Protected
Resources, NMFS, (301) 427-8401. Electronic copies of the application
and supporting documents, as well as a list of the references cited in
this document, may be obtained online at: https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act. In case of problems accessing these
documents, please call the contact listed above.
SUPPLEMENTARY INFORMATION:
Background
The MMPA prohibits the ``take'' of marine mammals, with certain
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to
allow, upon request, the incidental, but not intentional, taking of
small numbers of marine mammals by U.S. citizens who
[[Page 72309]]
engage in a specified activity (other than commercial fishing) within a
specified geographical region if certain findings are made and either
regulations are issued or, if the taking is limited to harassment, a
notice of a proposed incidental take authorization may be provided to
the public for review.
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for taking for subsistence uses
(where relevant). Further, NMFS must prescribe the permissible methods
of taking and other ``means of effecting the least practicable adverse
impact'' on the affected species or stocks and their habitat, paying
particular attention to rookeries, mating grounds, and areas of similar
significance, and on the availability of such species or stocks for
taking for certain subsistence uses (referred to in shorthand as
``mitigation''); and requirements pertaining to the mitigation,
monitoring and reporting of such takings are set forth.
The definitions of all applicable MMPA statutory terms cited above
are included in the relevant sections below.
National Environmental Policy Act
To comply with the National Environmental Policy Act of 1969 (NEPA;
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A,
NMFS must review our proposed action (i.e., the issuance of an
incidental harassment authorization) with respect to potential impacts
on the human environment. This proposed action is consistent with
categories of activities identified in Categorical Exclusion B4
(incidental harassment authorizations with no anticipated serious
injury or mortality) of the Companion Manual for NOAA Administrative
Order 216-6A, which do not individually or cumulatively have the
potential for significant impacts on the quality of the human
environment and for which we have not identified any extraordinary
circumstances that would preclude this categorical exclusion.
Accordingly, NMFS has preliminarily determined that the issuance of the
proposed IHA qualifies to be categorically excluded from further NEPA
review.
We will review all comments submitted in response to this notice
prior to concluding our NEPA process or making a final decision on the
IHA request.
Summary of Request
On August 14, 2019, NMFS received a request from CDFW for an IHA to
take marine mammals incidental to Elkhorn Slough Tidal Marsh
Restoration Project, Phase II; e.g., using heavy equipment to restore
58 acres of saltmarsh habitat. The application was deemed adequate and
complete on November 4, 2019. California Department of Fish and
Wildlife's request is for take of a small number of Pacific harbor
seals (Phoca vitulina richardii) by Level B harassment only. Neither
CDFW nor NMFS expects serious injury or mortality to result from this
activity and, therefore, an IHA is appropriate.
NMFS previously issued an IHA to CDFW for related work (Phase I of
the Elkhorn Slough Tidal Marsh Restoration Project; XRIN 0648-XE687).
CDFW complied with all the requirements (e.g., mitigation, monitoring,
and reporting) of the previous IHA and information regarding their
monitoring results may be found in the Estimated Take section.
This proposed IHA would cover one year of a larger project for
which CDFW obtained prior IHAs and intends to request take
authorization for subsequent facets of the project. The larger project
involves restoring 147 acres of vegetated tidal salt marsh, upland
ecotone, and native grasslands in Monterey County. CDFW complied with
all the requirements (e.g., mitigation, monitoring, and reporting) of
the previous IHA and information regarding their monitoring results may
be found in the Estimated Take section.
Description of Proposed Activity
Overview
In response to years of anthropogenic degradation (e.g., diking and
marsh draining), the CADFW seeks to restore 147 acres of vegetated
tidal salt marsh, upland ecotone, and native grasslands of Elkhorn
Slough (Monterey, California). Phase I of the Elkhorn Slough Tidal
Marsh Restoration Project, completed in 2018, restored 61 acres of
marsh. Phase II aims to restore 58 acres of saltmarsh habitat by using
heavy equipment to relocate soil from an upland area, south of the
Minhoto-Hester Restoration Area, within an 11 month work period.
Construction activities are expected to produce airborne noise and
visual disturbance that have the potential to result in behavioral
harassment of Pacific harbor seals (Phoca vitulina richardii). NMFS is
proposing to authorize take, by Level B Harassment, of Pacific harbor
seals as a result of the specified activity.
Over the past 150 years, human activities have altered the tidal,
freshwater, and sediment processes, which are essential to support and
sustain Elkhorn Slough's estuarine habitats. Fifty percent of the tidal
salt marsh in the Slough has been lost during this time period. This
habitat loss is primarily a result of two historic land use changes,
(1) construction of a harbor at the mouth of the Slough and the related
diversion of the Salinas River, which lead to increased tidal flooding
(and subsequent drowning of vegetation) and (2) past diking and
draining of the marsh for use as pasture land. The act of draining
wetlands led to sediment compaction and land subsidence, from one to
six feet. Decades later, the dikes began to fail, reintroducing tidal
waters to the reclaimed wetlands. Rather than converting back to salt
marsh, the areas converted to poor quality, high elevation intertidal
mudflat, as the lowered landscape was inundated too frequently to
support tidal marsh, and insufficient sediment supply was available in
the tidal waters to rebuild elevation. The loss of riverine sediment
inputs, continued subsidence of marsh areas, sea level rise, increased
salinity, and increased nutrient inputs may also contribute to marsh
loss (Watson et al., 2011). Bank and channel erosion in the Elkhorn
Slough are also leading to deepening and widening tidal creeks, causing
salt marshes to collapse into the channel, and eroding sediments that
provide important habitat and support estuarine food webs.
The proposed project involves using heavy equipment to raise,
excavate, and reposition soil from the borrow area to the remnant marsh
plain. It would improve marsh sustainability with sea level rise, as
the restored marsh would be higher in the tidal frame, further from the
drowning threshold, and marsh vegetation in the restored areas would
accrete organic material that would help the restored marsh plain rise
with sea level. It would also reduce tidal prism in Elkhorn Slough,
reducing the potential for ongoing tidal scour and associated marsh
loss. The Minhoto-Hester Restoration Area is key to restoring hydrology
to the Phase I restoration area and the Seal Bend Restoration Area is
important for both habitat restoration and to maintain the
configuration of the main channel of Elkhorn Slough as the remnant
levee in the area has almost disintegrated.
Dates and Duration
Construction activities are anticipated to begin in January 2020,
after all permits are secured, and take 11 months to complete. Some
deviation in timing could result from unforeseen events
[[Page 72310]]
such as weather, logistical issues, or mechanical issues with
construction equipment. If a break in construction activities does
occur, the construction period will be extended by the length of the
break without exceeding the one-year window permitted by this IHA. The
construction period assumes that the construction contractors would
work between sunrise and sunset, Monday through Friday. However, some
construction activity may also be required during these times on
Saturdays. Due to the nature and location of the proposed work
schedule, the potential exposure to Pacific harbor seals would be
confined to six of the 11 months (180 days).
Specific Geographic Region
The proposed project is located in the Elkhorn Slough estuary,
situated 90 miles south of San Francisco and 20 miles north of
Monterey, is one of the largest estuaries in CA, and contains the
State's largest salt marshes south of San Francisco Bay (see Figure 1.
of the application). Specifically, the project sites are located on
land owned and operated by CADFW as part of the Elkhorn Slough
Ecological and National Estuarine Research Reserves. The waters of the
Elkhorn Slough State Marine Reserve and Monterey Bay National Marine
Sanctuary run north of Phase II's project sites in Elkhorn Slough's
main channel. Two additional Marine Protected Areas are located within
approximately one mile of the project site: Elkhorn Slough State Marine
Conservation Area and Moro Cojo Slough State Marine Reserve.
The Elkhorn Slough system is a network of intertidal marshes,
mudflats, and subtidal channels located at the center of the Monterey
Bay shoreline. With an average depth of 4.6 feet, it is the deepest at
the SR 1 bridge overcrossing where it measures 25 feet deep at mean
lower low water (MLLW). The main channel in Elkhorn Slough becomes
narrower and shallower as it winds inland.
Phase II work would occur within two tidal restoration areas: The
Minhoto-Hester Restoration Area (subareas M4a-b, M5, and M6) and the
Seal Bend Restoration Area (subareas S1-S4) (see Figure 2 from
application), 29.3 and 28.6 acres, respectively. Both are low-lying
areas consisting of subsided pickleweed marsh, intertidal mudflats,
tidal channels, and remnant levees. The Minhoto-Hester Marsh has
multiple cross-levees as well as, natural and dredged channels with a
major dredged channel (100+ ft. wide in some locations) that runs north
to south through the remnant marsh. Seal Bend has also has been divided
by multiple cross-levees, and has the heavily eroded remnants of a
perimeter levee along its outboard side. A large borrow channel is
located adjacent to the interior of the perimeter levee.
Mixed use lands encompass the slough's boundaries; their activities
may influence anticipated behavioral responses and ambient noise
levels. To the north are hilly uplands and marine terraces that lie
between the Pajaro and Salinas valleys. Upland areas drain into Elkhorn
Slough through numerous small ephemeral creeks. The largest of these is
Carneros Creek at the head of the estuary. Land use in these uplands
consists of agriculture (primarily strawberries and other row crops),
cattle grazing, rural residences, and the small town of Las Lomas.
Wetlands, mudflats, and marsh areas on both sides of Elkhorn Slough
characterize the immediate project setting. Located at the mouth of the
bay, a marina and kayak rentals accommodate recreational boaters.
Recreational vessels are restricted to the main channel of Elkhorn
Slough, just outside the project area. To the south of Elkhorn Slough
is an industrial park that comprises a natural gas powered electricity
plant and a chemical plant. Southeast of Seal Bend is a dairy farm and
further east, south of Yampah Marsh, is a vehicle dismantling and
recycling yard. The Union Specific Railroad (UPRR) traverses the
reserve, north to south, east of the main channel.
Detailed Description of Specific Activity
Phase II plans to restore 58-acres of saltmarsh habitat, including
53-acres of subsided marsh within the Minhoto-Hester Restoration Area
(sub-areas M4a-b, M5, and M6) and the Seal Bend Restoration Area
(subareas S1-S4); 2 acres of tidal channels and an additional 3 acres
of intertidal salt marsh created at an upland borrow area. To restore
hydrologic function to the project area they propose raising the
subsided marsh plain, maintaining or re-excavating the existing tidal
channels, and excavating within the upland buffer area to restore marsh
plain, ecotone, and native grassland habitat.
Up to 276,000 cubic yards (CY) of soil will be obtained from an
upland borrow area, south of the Minhoto-Hester Restoration Area (see
Figure 2 from the application), to raise the marsh plain elevations to
allow emergent wetland vegetation to naturally reestablish and
persevere. Sediment would be placed to a fill elevation slightly higher
than the target marsh plain elevation permitting settlement and
consolidation of the underlying soils. The average fill depth would be
2.1 feet, including 25 percent overfill.
Table 1 (same as Table 1 from the application) below presents the
acreages and extents of proposed fill within each marsh sub-area, as
well as the volume of fill required for each marsh sub-area to be
restored. The upland borrow area, onsite, would be used as the fill
source. The project would rely primarily on natural vegetation
recruitment in the restored marsh areas.
[[Page 72311]]
[GRAPHIC] [TIFF OMITTED] TN31DE19.006
Water Control and Tidal Channels of the Restoration Area
Work areas on the remnant marsh plain would for the most part be
isolated from the tides and dewatered to allow work in non-tidal
conditions. Water control structures such as temporary berms,
constructed without the use of pile driving, would be utilized to
isolate the fill placement area during the construction period; note,
that while we refer to the work broadly as ``construction,'' no
permanent installation of structures is included. Existing berms would
be used, where possible, and tidal channels in this area will be
blocked. The isolated work areas would be drained using a combination
of gravity and pumps. Water levels within the blocked areas would be
managed to keep them mostly free of water (with some ponded areas
remaining) and to allow fill placement at all stages of the tides. To
reduce the potential for fish to become entrained in isolated ponded
areas, blocking of tidal channels would occur at low tide. When
sediment placement is completed, the berms would be lowered to the
target marsh elevation, reintroducing tidal inundation.
Remnant historic channels onsite would generally be left in place
or filled and re-excavated in the same place. As needed for marsh
access, smaller channels would be filled. Avoidance of channel fill,
temporary and permanent, is preferred. As much of the existing tidal
channel network would be maintained as is feasible, and the post-
project channel alignments would be similar to those under existing
conditions. The density of channels (length of channel per acre of
marsh) after restoration would be comparable to the density in natural
reference marshes. Low levees (less than 0.5 feet above the marsh
plain) composed of fill material would be constructed along the larger
channels to simulate natural channel levees. Fill would be placed as
close to the edge of the channel as possible to simulate the form and
function of a natural channel bank. Borrow ditches that date from the
times of historical wetland reclamation in these areas would be blocked
or filled completely if fill is available after raising the marsh
plain. Blocking borrow ditches would route more flow through the
natural channels and slightly increase hydraulic resistance, which may
achieve benefits from reducing tidal prism and associated scour in the
Elkhorn Slough system.
To limit trip distances onto the marsh, the project would employ
one or more of the following placement approaches. Temporary channel
crossings may be constructed, or tidal channels may be temporarily
filled and then re-dug with an excavator or backhoe. If re-excavation
of the smaller channels proves infeasible, these channels may be
permanently filled, the resulting channel extent consisting of the
larger channels only. The resulting channel extent would be sufficient
to provide drainage and tidal exchange to support natural marsh
functions. The number and locations of channel crossings would depend
on the tradeoff between haul distances and the ease of installing and
removing the crossings. Where tidal channels were maintained in place,
turbidity control measures (i.e., Best Management Practices [BMPs]),
such as hay bales or weed free straw wattles) could be staked down in
or adjacent to the channels to be preserved. Bulldozers would push fill
up to the hay bales and wattles, but not into the channels. Channel
crossings and BMPs would be removed at project completion.
Buffer Area
The buffer area would be graded to create an ecotone band along the
edge of the restored marsh and/or native grassland habitat (see Figure
2. of the application). Specifically, about three acres of the buffer
area would be graded to create intertidal salt marsh and five acres
would be revegetated with native dominated perennial grassland adjacent
to subareas M4 and M5. The native grassland areas would be revegetated
by reducing the weed seed bank and planting native grasses/forbs. A
weed-resistant border of rhizomatous perennial plants that readily
spreads (e.g., creeping wild rye [Elymus triticoides] or Santa Barbara
sedge [Carex barbarae]) would be planted between the grassland and
ecotone. Remaining scraped areas within the borrow area would be
planted in a cover crop until local material is propagated to expand
grassland restoration.
[[Page 72312]]
Construction Sequencing and Equipment
Construction sequencing would begin with water management and/or
turbidity control measures constructed around the work areas prior to
placing material on the marsh. After fill placement on the marsh, any
temporary features, such as water management berms would be removed.
Construction equipment would include haul trucks, heavy earthmoving
equipment, such as dozers, backhoes, loaders, and excavators to
transport dry material out onto the marsh. All heavy equipment used to
transport dry material out onto the marsh would be of low ground
pressure to prevent sinking in the mud. Mats would be temporarily
placed on the marsh, as needed, to spread the weight of the equipment.
At the end of construction in each cell/stage, any elevated haul roads
and/or berms constructed to aid in material placement would be
excavated to design grades, with the resulting earth used to fill
adjacent restoration areas.
Proposed mitigation, monitoring, and reporting measures are
described in detail later in this document (please see Proposed
Mitigation and Proposed Monitoring and Reporting).
Description of Marine Mammals in the Area of Specified Activities
Sections 3 and 4 of the application summarize available information
regarding status and trends, distribution and habitat preferences, and
behavior and life history, of the potentially affected species.
Additional information regarding population trends and threats may be
found in NMFS's Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species
(e.g., physical and behavioral descriptions) may be found on NMFS's
website (https://www.fisheries.noaa.gov/find-species).
Table 2 lists all species with expected potential for occurrence in
Elkhorn Slough and summarizes information related to the population or
stock, including regulatory status under the MMPA and ESA and potential
biological removal (PBR), where known. For taxonomy, we follow
Committee on Taxonomy (2016). PBR is defined by the MMPA as the maximum
number of animals, not including natural mortalities, that may be
removed from a marine mammal stock while allowing that stock to reach
or maintain its optimum sustainable population (as described in NMFS's
SARs). While no mortality is anticipated or authorized here, PBR and
annual serious injury and mortality from anthropogenic sources are
included here as gross indicators of the status of the species and
other threats.
Marine mammal abundance estimates presented in this document
represent the total number of individuals that make up a given stock or
the total number estimated within a particular study or survey area.
NMFS's stock abundance estimates for most species represent the total
estimate of individuals within the geographic area, if known, that
comprises that stock. For some species, this geographic area may extend
beyond U.S. waters. All managed stocks in this region are assessed in
NMFS's U.S. Marine Mammal SARs: 2015 (Carretta et al.). All values
presented in Table 2 are the most recent available at the time of
publication and are available in the 2018 SARs (Carretta et al., 2018)
and draft 2019 SARs (available online at: https://www.fisheries.noaa.gov/national/marine-mammal-protection/draft-marine-mammal-stock-assessment-reports).
Table 2--Harbor Seal Status Information
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ESA/MMPA status; Stock abundance (CV,
Common name Scientific name Stock strategic (Y/N) Nmin, most recent PBR Annual M/
\1\ abundance survey) \2\ SI \3\
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Family Phocidae (earless seals):
Pacific Harbor Seal............. Phoca vitulina California............... -;N 30,968 seals (CV = 1,641 43
richardii. 0.157,Nmin = 27,348,
2012).
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\1\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\2\ NMFS marine mammal stock assessment reports online at: www.nmfs.noaa.gov/pr/sars/. CV is coefficient of variation; Nmin is the minimum estimate of
stock abundance. In some cases, CV is not applicable.
\3\ These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g.,
commercial fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV
associated with estimated mortality due to commercial fisheries is presented in some cases.
Note--Italicized species are not expected to be taken or proposed for authorization.
As described below, the Pacific harbor seal temporally and
spatially co-occur with the activity to the degree that take is
reasonably likely to occur, and we have proposed authorizing it.
In addition, the Southern sea otter (Enhydra lutris nereis) may be
found in Elkhorn Slough. However, the Southern sea otter is managed by
the U.S. Fish and Wildlife Service and are not considered further in
this document.
Local Abundance and Habitat Use
Pacific harbor seals use Elkhorn Slough for hauling out, resting,
socializing, foraging, molting, and reproduction, but mainly use it as
a staging area for foraging in the Monterey Bay, as there is a limited
amount of foraging in the Slough (McCarthy 2010). They are central
place foragers, tend to exhibit strong site fidelity within-season and
across years, generally forage close to haul-out sites, and may
repeatedly visit specific foraging areas (Grigg et al., 2012). Harbor
seals inhabit Elkhorn Slough year-round and occur individually or in
groups, but their abundance may change seasonally depending on prey
availability, molting and reproduction (McCarthy 2010). Molting takes
place each summer after pupping, when harbor seals haul out more
frequently and for longer periods, than in autumn or winter (Stewart
and Yochem 1994).
[[Page 72313]]
Counts of harbor seals in the greater Elkhorn Slough began in 1975
and at that time averaged about 30 seals (Harvey et al., 1995, Oxman
1995). The population in the greater Elkhorn Slough is currently
estimated at 300 to 500 seals (McCarthy 2010). Harbor seal count data
as reported were collected from a variety of sources using various
methodologies. Data on harbor seal use near the project area is derived
from marine mammal monitoring data collected by the Reserve Otter
Monitoring Project (Elkhorn Slough National Estuarine Research Reserve
2018) and Phase I construction monitoring (Fountain et al., 2019).
Harbor seals have utilized the Elkhorn Slough as a resting site
since the 1970s, but the first births were not recorded until 1991
(Maldini et al., 2010). From 1995 to 1997, there was a significant
annual increase in pups, from 14 seals in 1995 to 29 seals in 1997
(Richman, 1997). The increase of the Elkhorn Slough population and
pupping frequency is attributed to a combination of three major
factors: Overall increase in abundance leading to increased competition
for space and population expansion, migration of young seals to the
area, and decreased harassment by humans. Furthermore, marine mammal
experts speculate the increase was due to removal of public restrooms
from the Seal Bend area in the early 1990s (McCarthy 2010). Pupping can
occur throughout the year, but generally starts in late March and peaks
in May. Some seals may depart during pupping/breeding season to other
breeding areas outside of Elkhorn Slough. Females tend to remove
themselves from the group to give birth and return within a week
(McCarthy 2010). In 2010, 50 pups were observed in Elkhorn Slough (J.
Harvey unpublished data in McCarthy, 2010), but the specific location
within the Slough was not documented and the applicant indicates that
they have not documented births within the project area.
Seal Haul Outs Potentially Impacted by Project Activities
Harbor seals prefer areas with full tidal exchange; McCarthy (2010)
reports them frequenting areas just beyond the mouth of Elkhorn Slough
in the Moss Landing harbor and in the Salinas River channel south of
the Moss Landing bridge, and the lower portion of Elkhorn Slough
extending up to Parsons Slough and Rubis Creek. Figure 3 from the
application, depicts known and potential haul[hyphen]out areas used by
harbor seals proximate to the project area. They typically use the
corridor from the mouth of Elkhorn Slough through the Moss Landing
Harbor entrance for nightly feeding in Monterey Bay (J. Harvey, pers.
comm. in McCarthy, 2010). In a diet study conducted between 1995 and
1997, 35 species including topsmelt, white croaker, spotted cusk-eel,
night smelt, bocaccio, Pacific herring, a brachyuran crustacean, and 4
genera of mollusks were consumed by harbor seals (Harvey et al., 1995,
McCarthy 2010).
For Phase II restoration activities, the ``Seal Bend'' observation
area is most representative of seal use at the Seal Bend restoration
area; the ``Hester 2'' observation area is most representative of seal
use at the Minhoto-Hester restoration area. Other monitoring locations
that may support seals that transit or haul out near the proposed Phase
II restoration areas and that could be disturbed by construction
activities include ``Wildlife'', ``Moon Glow'', ``Upper Dairy (also
referred to as ``Main Channel''), ``Yampah'', and ``Avila''. Excluding
the haul-outs in the project area during construction would temporarily
remove less than 2% of the potential haul-out areas in the slough
(i.e., based on similar tidal range).
Potential Effects of Specified Activities on Marine Mammals and Their
Habitat
This section includes a summary and discussion of the ways that
components of the specified activity may impact marine mammals and
their habitat. The Estimated Take by Incidental Harassment section
later in this document includes a quantitative analysis of the number
of individuals that are expected to be taken by this activity. The
Negligible Impact Analysis and Determination section considers the
content of this section, the Estimated Take by Incidental Harassment
section, and the Proposed Mitigation section, to draw conclusions
regarding the likely impacts of these activities on the reproductive
success or survivorship of individuals and how those impacts on
individuals are likely to impact marine mammal species or stocks.
Harbor seals that use the haul-out sites Seal Bend and Hester 2,
within and near the footprint of the construction areas (as described
in the previous section, Description of Marine Mammals in the Area of
Specified Activities) may potentially experience behavioral disruption
rising to the level of harassment from construction activities. This
may include visual disturbance due to the presence and activity of
heavy equipment, construction workers, and biological monitors, as well
as airborne noise from the equipment. Disturbed seals are likely to
experience any or all of these stimuli, and take may occur due to any
of these in isolation or in combination with the others.
Construction activities have the potential to cause behavioral
harassment to seals that may be hauling out, resting, foraging, or
engaging in other activities either inside or near the project area.
Human disturbance of harbor seals can strongly affect their abundance
and distribution in estuaries. Some or all of the seals present would
be expected to move or flush in response to the presence of crew and
equipment, though some may remain hauled out. Individuals or groups of
seals can experience levels of behavioral disturbance along a continuum
of responses: (1) Lifting the head and/or sitting up (alert), (2)
movement, or (3) retreating to the water (flushing). The level of human
disturbance to seals is dependent on various factors, such as how the
site is used by seals, proximity of disturbance (Allen et al., 1984,
Osborn 1985, Suryan and Harvey 1999), and duration and frequency of
disturbances (Osborn 1985). The impacts of temporary or permanent site
abandonment (flight) due to disturbance can include changes in haul-out
pattern, which can also affect feeding patterns, and, potentially,
reduce pup survival from mother/pup separation and interrupted suckling
bouts if disturbance were to occur in longer durations in the vicinity
of mother-pup pairs. Tolerance to disturbance may be lower during
pupping season (Osborn 1985).
Anthropogenic Airborne Sound Levels
Because of the various activities within and surrounding Elkhorn
Slough, as discussed in the Specific Geographic Region Section above,
resident seals may already be habituated to noise from these
established human activities. Noise levels were monitored during a
restoration project at Parson's Slough, adjacent to Minhoto-Hester
Marsh, in 2010 and 2011. Background noise during that project was
approximately 57 dBC Lmax (dbC can be defined as dB with C-
weighting which is a standard weighting of the audible frequencies
commonly used for the measurement of Peak Sound Pressure Level [SPL]
and Lmax is defined as the maximum sound level during a
single noise event) as measured at 20 and 40 meters northeast of the
pile installation site and approximately 1.5 meters above the ground
(ESNERR 2011). Approximately 15 to 20 trains pass along the UPRR each
day, which is located within 400 feet of the eastern-most portion of
the project site (Vinnedge Environmental Consulting 2010). Noise levels
from trains were
[[Page 72314]]
monitored during construction of the Parson's Slough Project and
estimated at 108 dBC Lmax. Noise is also generated from
Pick-n-Pull, a vehicle dismantling yard and recycling yard, located
approximately 300 feet from the project site. Lastly, agricultural
equipment operated within the existing uplands and haul trucks that
travel regularly across adjacent agricultural lands and along nearby
levees, also contribute to the ambient noise of Elkhorn Slough.
Although no specific measurements have been made at the project
area, it is reasonable to believe that levels may generally be similar
to the previous project at Parson's Slough as there is a similar type
and degree of activity within the same type of environment (tidal salt
marsh). Known sound levels and frequency ranges associated with
anthropogenic sources similar to those associated to this project are
summarized in Table 3.
Table 3--Representative Airborne Sound Levels of Anthropogenic Sources--
dB re: 20[mu]Pa
------------------------------------------------------------------------
Sound source Airborne sound level Reference
------------------------------------------------------------------------
Heavy Earth Moving Equipment 80-90 dB at 15.24 m. FHWA, 2015.
(i.e., excavators,
backhoes, and front
loaders).
UPPR trains................. 108 dBC Lmax at 20 m ESNERR, 2011
and 40 m (northeast (Parson's Slough).
of the pile
installation).
------------------------------------------------------------------------
Airborne noise associated with this project includes noise from
construction activities during the restoration of the tidal marsh.
Airborne noise produced from earth moving equipment (i.e., backhoes,
front end loaders) for construction, may produce sound levels at 80 to
90 dB at 15.24 m (FHWA, 2015) (Table 3). The construction activity may
generate noise above ambient levels or create a visual disturbance for
a period of 11 months; however, the exact distance of disturbance from
noise is unknown. Trains along the UPRR likely generate fairly high
noise levels in the eastern portion of the project area, so earth
moving equipment operated in this area may not elevate ambient noise
levels when trains are present.
Anthropogenic airborne sound could cause hauled out pinnipeds to
exhibit changes in their normal behavior, such as reduction in
vocalizations, or cause them to move further from the source or
temporarily abandon their habitat. Studies by Blackwell et al., (2004)
and Moulton et al., (2005) indicate a tolerance or lack of response to
unweighted airborne sounds as high as 112 dB peak and 96 dB root mean
square (rms).
Due to the nature of the activities, it is unlikely that injurious
or lethal takes would occur even in the absence of the planned
mitigation and monitoring measures. Further, the proposed mitigation
and monitoring measures are expected to minimize the possibility of
take by Level A harassment, such that it is not addressed further.
During the 9-month construction window associated with Phase I
construction, marine mammal monitoring was required and implemented on
89 days (976 hours of monitoring). During this period, there were 19
observed incidents of Level B harassment of harbor seals (flushing or
movement) that were recorded by the monitors. Of these, 16 incidents,
representing harassment of 62 individual seals, were attributed to
construction activity or marine mammal monitoring; the remaining three
incidents were unrelated to the project (e.g., seals flushing as a
result of a passing boat in Elkhorn Slough) (Table 3 in the
application). When Level B harassment occurred, it was always when
seals were within 300 meters of the disturbance source; most were when
distances were 100 meters or less (Fountain et al. 2019). In addition,
not all seals located in the vicinity of the disturbance flushed or
moved during each discrete incident; for example, in nine incidents,
less than one third of the seals present in the area flushed. Relative
to the average number of seals observed per day during monitoring,
approximately 2% were disturbed by construction or monitoring
activities. Seals that move or flush are expected to use other areas of
the slough available as haul out sites.
Changes to Habitat
The primary potential impact to marine mammal habitat associated
with the construction activity is the exclusion from the accustomed
haul out areas. During the restoration, the inability of seals to use
suitable habitat within the footprint of the construction area would
temporarily remove less than 2% of the potential haul out areas in
Elkhorn Slough. Although the proposed action would permanently alter
habitat within the footprint of the construction area, harbor seals
haul out in many locations throughout the estuary, and the proposed
activities are not expected to have any habitat-related effects that
could cause significant or long-term consequences for individual harbor
seals or their population. The restoration of the marsh habitat will
have no adverse long-term effect on marine mammal habitat, but possibly
a long-term beneficial effect on harbor seals by improving ecological
function of the slough, inclusive of higher species diversity,
increased species abundance, larger fish, and improved habitat.
Harbor seals that use the eastern portion of the Minhoto-Hester
Restoration Area (up to 50 seals) would be inhibited from hauling-out
or resting within the project area during the 11-month construction
period. The site would be isolated outside of the peak-pupping season
to avoid impacts to mothers with pups. Non-breeding seals that would
have utilized the project area for hauling-out or resting would be
displaced. However, seals could use other areas of Elkhorn Slough for
resting and haul-out during construction, which would minimize impacts
to seals.
Conversion of mudflat back to tidal marsh will have an overall
beneficial effect on the Elkhorn Slough system and possibly increase
habitat for harbor seals. Harbor seals use a small portion of the
channel edges within the subsided marsh (now mudflat). By raising the
elevation of the marsh, and increasing the extent of tidal marsh, tidal
prism would be reduced and possibly increase the extent of haul-out
habitat (McCarthy 2010). This reduction would slow erosion and sediment
and marsh loss within the slough system. It is expected to reduce the
loss of soft sediment habitat within the slough that support prey
species of marine mammals.
Increasing the extent of tidal marsh would also improve water
quality by establishing a buffer to absorb upland contaminants and
agricultural runoff coming from the Old Salinas River mouth. Improved
water quality could increase prey abundance and decrease toxin
concentrations in seal tissues resulting in a positive effect on harbor
seal abundance and distribution (McCarthy 2010).
[[Page 72315]]
Estimated Take
This section provides an estimate of the number of incidental takes
proposed for authorization through this IHA, which will inform both
NMFS' consideration of ``small numbers'' and the negligible impact
determination.
Harassment is the only type of take expected to result from these
activities. Except with respect to certain activities not pertinent
here, section 3(18) of the MMPA defines ``harassment'' as any act of
pursuit, torment, or annoyance, which (i) has the potential to injure a
marine mammal or marine mammal stock in the wild (Level A harassment);
or (ii) has the potential to disturb a marine mammal or marine mammal
stock in the wild by causing disruption of behavioral patterns,
including, but not limited to, migration, breathing, nursing, breeding,
feeding, or sheltering (Level B harassment).
Authorized takes would be by Level B harassment only, in the form
of disruption of behavioral patterns for individual marine mammals
resulting from exposure to the stressor/s--pedestrian traffic,
biological monitors, construction workers, and use of heavy machinery.
Based on the nature of the activity, Level A harassment is neither
anticipated nor proposed to be authorized.
As described previously, no mortality is anticipated or proposed to
be authorized for this activity. Below we describe how the take is
estimated.
Generally speaking, we estimate take by considering: (1) Acoustic
thresholds above which NMFS believes the best available science
indicates marine mammals will be behaviorally harassed or incur some
degree of permanent hearing impairment; (2) the area or volume of water
or air that will be ensonified above these levels in a day; (3) the
density or occurrence of marine mammals within these ensonified areas;
and, (4) and the number of days of activities. We note that while these
basic factors can contribute to a basic calculation to provide an
initial prediction of takes, additional information that can
qualitatively inform take estimates is also sometimes available (e.g.,
previous monitoring results or average group size). Below, we describe
the factors considered here in more detail and present the proposed
take estimate.
Acoustic Thresholds
Using the best available science, NMFS has developed acoustic
thresholds that identify the received level of underwater sound above
which exposed marine mammals would be reasonably expected to be
behaviorally harassed (equated to Level B harassment) or to incur PTS
of some degree (equated to Level A harassment). Thresholds have also
been developed identifying the received level of in-air sound above
which exposed pinnipeds would likely be behaviorally harassed.
Level B Harassment for non-explosive sources--Though significantly
driven by received level, the onset of behavioral disturbance from
anthropogenic noise exposure is also informed to varying degrees by
other factors related to the source (e.g., frequency, predictability,
duty cycle), the environment (e.g., bathymetry), and the receiving
animals (hearing, motivation, experience, demography, behavioral
context) and can be difficult to predict (Ellison et al., 2012,
Southall et al., 2007). Based on what the available science indicates
and the practical need to use a threshold based on a factor that is
both predictable and measurable for most activities, NMFS uses a
generalized acoustic threshold based on received level to estimate the
onset of behavioral harassment. NMFS predicts that marine mammals are
likely to be behaviorally harassed in a manner we consider Level B
harassment when exposed to underwater anthropogenic noise above
received levels of 120 dB re 1 microPascal ([mu]Pa), (rms) for
continuous (e.g., vibratory pile-driving, drilling) and above 160 dB re
1 [mu]Pa (rms) for non-explosive impulsive (e.g., seismic airguns) or
intermittent (e.g., scientific sonar) sources. For in-air sounds, NMFS
predicts that harbor seals exposed above received levels of 90 dB re 20
[mu]Pa (rms) will be behaviorally harassed, and other pinnipeds will be
harassed when exposed above 100 dB re 20 [mu]Pa (rms).
CDFW's Elkhorn Slough Tidal Marsh Restoration Project, Phase II
includes the use of intermittent (construction activities) airborne
noise and visual disturbances, and therefore the 90 dB re 20 [mu]Pa
(rms) is applicable. We note, however, that the take estimates
(described in detail below) are based on occurrence in the general
area, rather than within any specific isopleth.
As indicated above, no Level A harassment is anticipated.
Marine Mammal Occurrence
In this section we provide the information about the presence,
density, or group dynamics of marine mammals that will inform the take
calculations.
Data on harbor seal use near the project area is derived from
marine mammal monitoring data collected by the Reserve Otter Monitoring
Project (ESNERR 2018) and Phase I construction monitoring (Fountain et
al., 2019).
The Reserve Otter Monitoring Project has been monitoring otter
movement and behavior in Elkhorn Slough since 2011. This effort has
been a collaboration between ESNERR, Monterey Bay Aquarium, United
State Geologic Survey and University of California Santa Cruz. In
January of 2018, they added seals to their observations, and have
compiled monitoring data for seals through April 2019. During this time
period, biologists conducted weekly monitoring at nine locations along
Elkhorn Slough and five locations in Moss Landing Harbor (Figure 4. in
the application). Seal and otter counts were completed every Tuesday,
every half hour on the hour and half hour, from 10 a.m.-12 p.m. Eight
teams were positioned concurrently throughout the estuary using high-
powered binoculars and scopes to see otters and seals. Data collected
included weather, observation time, tide, the number and species of
marine mammal sited, and the location they were observed. All
monitoring was completed by or under the supervision of a qualified
biologist previously approved by USFWS and NOAA Fisheries for marine
mammal monitoring.
Figure 5 (from the application) and Table 4 below, summarizes the
maximum number of seals observed by location on a single day of
monitoring, June 19, 2018. In addition, the maximum and average number
of seals observed during an hourly count at each of the seven monitored
locations proximate to the Phase II restoration areas over the 16-month
observation period (i.e., January 2018 to April 2019) are presented in
Table 4. Since the maximum and average seal counts were collected from
various days between January 2018 and April 2019, duplicate counts
(i.e., recording the same seal more than once), are considered highly
probable. These data are consistent with previous
[[Page 72316]]
Table 4--Harbor Seal Counts by Reserve Otter Monitoring Project
----------------------------------------------------------------------------------------------------------------
Hourly counts \3\
Location \1\ Highest daily -------------------------------
count \2\ Maximum Average
----------------------------------------------------------------------------------------------------------------
Wildlife........................................................ 88 106 41
Seal Bend....................................................... 59 86 24
Moonglow........................................................ 56 87 16
Hester.......................................................... 0 33 5
Main Channel.................................................... 0 100 30
Yampah.......................................................... 93 81 18
Avila........................................................... 1 122 32
-----------------------------------------------
Total....................................................... 417 615 166
----------------------------------------------------------------------------------------------------------------
\1\ See Figure 4 (from application) for location of observation area. ``Harbor'' includes incidental counts
outside of formal observation areas.
\2\ Represents highest count of seals recorded on a single day, June 19, 2018, during hourly counts.
\3\ Represents maximum and average number or seals observed during an hourly count at any location from
monitoring dates between January 2018 and April 2019 by Reserve Otter Monitoring Project.
population estimates by McCarthy (2010), which estimated the population
of seals in Elkhorn Slough at 300 to 500, with seasonal variability
based on prey availability, molting and reproduction. The data also
illustrate that seals tend to move between areas proximate to each
other. For example, when large numbers of seals were observed in
Parsons Slough (``Avila'') in the summer of 2018, there was a
comparable decline in the number of seals observed at Seal Bend (Figure
5, in the application).
During Phase I construction, marine mammal monitoring was required
and implemented on 89 days (976 hours of monitoring) within the 9-month
construction window. An average of 75 seals were recorded by marine
mammal monitors in the observation area at any given time, and up to
257 individual seals were observed near the Phase I restoration area in
a given day. Nineteen incidents of Level B harassment of harbor seals
(flushing or movement) were recorded by the monitors. Of these, 16
incidents, representing harassment of 62 individual seals, were
attributed to construction activity or marine mammal monitoring; the
remaining 3 incidents were unrelated to the project (e.g., seals
flushing as a result of a passing boat in Elkhorn Slough) (Table 5).
When Level B harassment occurred, it was always when seals were within
300 meters of the disturbance source; most were when distances were 100
meters or less (Fountain et al., 2019). In addition, not all seals
located in the vicinity of the disturbance flushed or moved during each
discrete incident; for example, in 9 incidents, less than one third of
the seals present in the area flushed. Relative to the average number
of seals observed per day during monitoring, approximately 2% were
disturbed by construction or monitoring activities.
Table 5--Phase I Harbor Seal Disturbance Data--Number of Seals Experiencing Level B Harassment (Movement,
Flushing) in Relation to Number of Seals Present
----------------------------------------------------------------------------------------------------------------
Number seals
Number seals Number seals in entire
Incident taken in vicinity observation
area
----------------------------------------------------------------------------------------------------------------
1............................................................... 12 16 17
2............................................................... 10 49 75
3............................................................... 2 2 3
4............................................................... 1 1 8
5............................................................... 2 12 31
6............................................................... 2 12 16
7............................................................... 2 12 16
8............................................................... 1 12 16
9............................................................... 3 3 3
10.............................................................. 4 7 8
11.............................................................. 2 5 36
12.............................................................. 6 43 107
13.............................................................. 2 17 26
14.............................................................. 6 14 31
15.............................................................. 3 3 54
16.............................................................. 4 6 6
-----------------------------------------------
Total....................................................... 62 214 453
----------------------------------------------------------------------------------------------------------------
Notes:
(1) ``number seals taken'' = seals that moved or flushed.
(2) ``Number seals in vicinity'' = o those proximate to the disturbance site.
Specific to the presence of pups during Phase I, Table 6 depicts
the maximum number of pups observed during hourly counts by month. This
metric conservatively represents the highest number of pups that could
be disturbed by project-related activities (including by monitoring
observers) at a given time.
[[Page 72317]]
Table 6--Maximum Number of Pups Observed During Hourly Counts by Month During Phase I Construction
----------------------------------------------------------------------------------------------------------------
Month Number of pups
----------------------------------------------------------------------------------------------------------------
2017:
December.......................................... 5
2018:
January........................................... 6
1February......................................... 9
March............................................. 4
April............................................. 7
May............................................... 15
June.............................................. 5
July.............................................. 9
August............................................ 9
----------------------------------------------------------------------------------------------------------------
Table 7 summarizes all occasions where monitors observed seal pups
reacting to Phase I project-related activities-- typically sound. All
responses were observed within 100m of project-related activities. This
metric conservatively represents the highest number of pups that could
be disturbed by project-related activities, either a monitor or
construction activities (typically sound), at a given time.
Table 7--Phase I Harbor Seal Pup Disturbance Data
----------------------------------------------------------------------------------------------------------------
Total number
Date Reaction Trigger Total number seals reacted Number pups
seals present \1\ reacted
----------------------------------------------------------------------------------------------------------------
4/11/18...................... Flush........... Monitor 18 6 3
(Visual).
4/11/18...................... Flush........... Construction 12 2 1
(Sound).
4/11/18...................... Flush........... Construction 10 2 1
(Sound).
4/11/18...................... Flush........... Construction 10 2 1
(Sound).
4/12/18...................... Alert........... Construction 17 2 1
(Sound and
Visual).
5/01/18...................... Flush........... Monitor 3 3 1
(Visual).
----------------------------------------------------------------------------------------------------------------
\1\ Includes all seals (adults, pups) that reacted to project-related disturbance.
No takes by Level A harassment, serious injury, or mortality are
expected from the disturbance associated with the construction
activities. It is unlikely a stampede (a potentially dangerous
occurrence in which large numbers of animals succumb to mass panic and
rush away from a stimulus) would occur or abandonment of pups. The
primary spots used for nursing and resting for mother/pup pairs has
been the entrance to Parson Slough, which is ~610 m east of Minhoto-
Hester restoration area and will not be affected by construction
activities (per comm Harvey 2019). Pacific harbor seals have been
hauling out in the project area and within the greater Elkhorn Slough
throughout the year for many years (including during pupping season and
while females are pregnant) while being exposed to anthropogenic sound
sources such as recreational vessel traffic, UPPR, and other stimuli
from human presence. The number of harbor seals disturbed would likely
also fluctuate depending on time day and tidal stage. Fewer harbor
seals will be present in the early morning and approaching evening
hours as seals leave the haul out site to feed and they are also not
present when the tide is high and the haul out is inundated.
Take Calculation and Estimates
Here we describe how the information provided above is brought
together to produce a quantitative take estimate.
Incidental take is calculated using the estimated number of seals
that will be present in project area during construction activities and
the anticipated percentage of those seals that will be taken based on
previous monitoring. Expected marine mammal presence is determined by
past observations--from Phase I of the restoration project and 16
months of data from the Reserve Otter Monitoring Project--and general
abundance during the construction window. Daily take estimates are
based on the average percentage of Level B disturbance observed during
Phase 1 construction (percent of seals taken) in the following
equation:
[GRAPHIC] [TIFF OMITTED] TN31DE19.007
The percentage was then rounded up to 2% and used to calculate the
daily take estimate. Upon review of CDFW's take calculation and
estimate, NMFS decided to calculate the daily take estimate using the
maximum number of seals observed in a day (417) at the seven locations,
proximate to the Phase II restoration areas, over a 16-month period by
the Reserve Otter Monitoring Project:
Daily Take Estimate = Average % of Seals Taken * Maximum Seals Observed
in a Day
The proposed authorized take was determined by multiplying the daily
take estimate (8.34) by the number of construction days (180), for
Phase II of the restoration project. Using this approach, a summary of
estimated takes of harbor seals incidental the project activities are
provided in Table 8. Estimates include Level B harassment as a result
of exposure to noise and visual disturbance during construction
activities.
[[Page 72318]]
Table 8--Calculated Take and Percentage of Stock Exposed
----------------------------------------------------------------------------------------------------------------
Proposed authorized take
Species ----------------------------------------------------- % population
Level B Level A \4\
----------------------------------------------------------------------------------------------------------------
A. Pacific Harbor Seal..................... 417 \1\ max seals/day(2% \2\)(180 N/A 5
days \3\) = 1502.
----------------------------------------------------------------------------------------------------------------
\1\ Maximum number of seals observed/day between January 2018 and April 2019 by Reserve Otter Monitoring
Project.
\2\ % Take from Phase I.
\3\ Number of construction days.
\4\ Data from U.S. Pacific Marine Mammal Stock Assessments: 2015 (Carretta et al., 2015).
All estimates proposed by the applicant and accepted by NMFS, are
considered conservative. Construction activities will occur in
sections, and some sections (e.g. S1-S4) are further away from seal
haul outs (approximately 100 m and greater). Noise from construction
activities in more southern sections may cause fewer disturbances to
seals. Not all seals that previously used the haul outs within the
footprint of the construction will use the haul outs just outside the
project. Some seals may seek alternative haul out habitat in other
parts of Elkhorn Slough.
Proposed Mitigation
In order to issue an IHA under Section 101(a)(5)(D) of the MMPA,
NMFS must set forth the permissible methods of taking pursuant to such
activity, and other means of effecting the least practicable impact on
such species or stock and its habitat, paying particular attention to
rookeries, mating grounds, and areas of similar significance, and on
the availability of such species or stock for taking for certain
subsistence uses (latter not applicable for this action). NMFS
regulations require applicants for incidental take authorizations to
include information about the availability and feasibility (economic
and technological) of equipment, methods, and manner of conducting such
activity or other means of effecting the least practicable adverse
impact upon the affected species or stocks and their habitat (50 CFR
216.104(a)(11)).
In evaluating how mitigation may or may not be appropriate to
ensure the least practicable adverse impact on species or stocks and
their habitat, as well as subsistence uses where applicable, we
carefully consider two primary factors:
(1) The manner in which, and the degree to which, the successful
implementation of the measure(s) is expected to reduce impacts to
marine mammals, marine mammal species or stocks, and their habitat.
This considers the nature of the potential adverse impact being
mitigated (likelihood, scope, range). It further considers the
likelihood that the measure will be effective if implemented
(probability of accomplishing the mitigating result if implemented as
planned), the likelihood of effective implementation (probability
implemented as planned), and;
(2) the practicability of the measures for applicant
implementation, which may consider such things as cost, impact on
operations, and, in the case of a military readiness activity,
personnel safety, practicality of implementation, and impact on the
effectiveness of the military readiness activity.
The following mitigation measures are planned in the IHA:
Timing Restrictions
All work will be conducted during daylight hours when visual
monitoring of marine mammals can be implemented. If poor environmental
conditions restrict full visibility of the shutdown zone, construction
activities would be delayed. No in-water work will be conducted at
night.
Shutdown Zone for In-Water Heavy Machinery Work
For in-water, heavy machinery work, if a marine mammal comes within
10 m of such operations, operations shall cease and vessels shall
reduce speed to the minimum level required to maintain steerage and
safe working conditions.
Construction Activities
A NOAA Fisheries and USFWS-approved biologist shall conduct
mandatory biological resources awareness training for construction
personnel. The awareness training shall be provided to all construction
personnel to brief them on the need to avoid effects on marine mammals.
If new construction personnel are added to the project, the contractor
shall ensure that the personnel receive the mandatory training before
starting work.
A NOAA Fisheries and USFWS approved biological monitor will monitor
for marine mammal disturbance. Monitoring will occur at all times when
work is occurring, (1) in water or (2); within 100 m of tidal waters.
Biological monitoring will begin 0.5-hour before work begins and will
continue until 0.5-hour after work is completed each day. The
biological monitor will have the authority to stop project activities
if marine mammals approach or enter the exclusion zone and/or at any
time for the safety of any marine mammals. Work will commence only with
approval of the biological monitor to ensure that no marine mammals are
present in the exclusion zone.
To reduce the risk of potentially startling marine mammals with a
sudden intensive sound, the construction contractor would begin
construction activities gradually each day by moving around the project
area and starting tractor one at a time.
Fuel storage and all fueling and equipment maintenance activities
will be conducted at least 100 feet from subtidal and intertidal
habitat.
Pupping Season
While CADFW expects the majority of pupping to take place at
Parson's Slough, outside of the project area, pupping location is left
to the mother's preference. Thus, in the event a pup comes within 20 m
of where heavy machinery is operating, construction activities in that
area will be delayed until the pup has left the area. In the event that
a pup remains within those 20 m, NMFS will be consulted to determine
the appropriate course of action.
If a pup less than one week old comes within 20 meters of where
heavy machinery is working, construction activities in that area would
be delayed until the pup has left the area. In the event that a pup
less than one week old remains within those 20 meters, NOAA Fisheries
would be consulted to determine the appropriate course of action.
Based on our evaluation of the applicant's proposed measures, as
well as other measures considered by NMFS, NMFS has preliminarily
determined that the proposed mitigation measures provide the means
effecting the least practicable impact on the affected species or
stocks and their habitat, paying particular attention to rookeries,
[[Page 72319]]
mating grounds, and areas of similar significance.
Proposed Monitoring and Reporting
In order to issue an IHA for an activity, Section 101(a)(5)(D) of
the MMPA states that NMFS must set forth requirements pertaining to the
monitoring and reporting of such taking. The MMPA implementing
regulations at 50 CFR 216.104 (a)(13) indicate that requests for
authorizations must include the suggested means of accomplishing the
necessary monitoring and reporting that will result in increased
knowledge of the species and of the level of taking or impacts on
populations of marine mammals that are expected to be present in the
proposed action area. Effective reporting is critical both to
compliance as well as ensuring that the most value is obtained from the
required monitoring.
Monitoring and reporting requirements prescribed by NMFS should
contribute to improved understanding of one or more of the following:
Occurrence of marine mammal species or stocks in the area
in which take is anticipated (e.g., presence, abundance, distribution,
density).
Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) Action or environment
(e.g., source characterization, propagation, ambient noise); (2)
affected species (e.g., life history, dive patterns); (3) co-occurrence
of marine mammal species with the action; or (4) biological or
behavioral context of exposure (e.g., age, calving or feeding areas).
Individual marine mammal responses (behavioral or
physiological) to acoustic stressors (acute, chronic, or cumulative),
other stressors, or cumulative impacts from multiple stressors.
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of individual marine mammals; or (2)
populations, species, or stocks.
Effects on marine mammal habitat (e.g., marine mammal prey
species, acoustic habitat, or other important physical components of
marine mammal habitat).
Mitigation and monitoring effectiveness.
Pre-Activity Monitoring
Pre and post construction daily censuses--A census of marine
mammals in the project area and the area surrounding the project will
be conducted 30 minutes prior to the beginning of construction on
monitoring days, and again 30 minutes after the completion of
construction activities. The following data will be collected:
Environmental conditions (weather condition, tidal conditions,
visibility, cloud cover, air temperature and wind speed), recorded
during pre- and post-construction daily census counts
Numbers of each species spotted
Location of each species spotted
Status (in water or hauled out)
Behavior
Hourly counts--Conduct hourly counts of animals hauled out and in
the water.
Data collected will include:
Numbers of each species
Location, including zone and whether hauled out or in the
water
Time
Tidal conditions
Primary construction activities occurring during the past hour
Number of mom/pup pairs and neonates observed
Notable behaviors, including foraging, grooming, resting,
aggression, mating activity, and others
Tag color and tag location (and tag number if possible)--for
sea otters, note right or left flipper and location between digits
(digits 1 and 2 are inside; digits 4 and 5 are outside)
Notes may include any of the following information to the extent it
is feasible to record:
Age-class
Sex
Unusual activity or signs of stress
Any other information worth noting
Construction related reactions
Record reaction observed in relation to construction activities
including:
Time of reaction
Concurrent construction activity
Location of animal during initial reaction and distance from
the noted disturbance
Activity before and after disturbance
Status (in water or hauled out) before and after disturbance
Table 9--Code Reactions
----------------------------------------------------------------------------------------------------------------
Level Type of response Definition
----------------------------------------------------------------------------------------------------------------
1.................................... Alert.................. Seal head orientation or brief movement in
response to disturbance, which may include
turning head towards the disturbance, craning
head and neck while holding the body rigid in a
u-shaped position, changing from a lying to a
sitting position, or brief movement of less
than twice the animal's body length. Alerts
will be recorded, but not counted as a `take'.
2.................................... Movement............... Movements away from the source of disturbance,
ranging from short withdrawals at least twice
the animal's body length to longer retreats, or
if already moving a change of direction of
greater than 90 degrees. These movements will
be recorded and counted as a `take'.
3.................................... Flush.................. All retreats (flushes) to the water. Flushing
into the water will be recorded and counted as
a `take'.
----------------------------------------------------------------------------------------------------------------
Steps for Shutting Down and Resuming Construction
1. Alert construction foreman of animal using the red flag and handheld
radio (use 1 blow from air horn if needed)
2. Record the construction activity and the time of shutdown
3. Record the reaction and location of the animal
4. Give clearance signal (green flag) and handheld radio for
construction activities when animal is seen outside of 10-meter zone
and traveling away from the construction area, or when the animal is
not spotted for 15 minutes
5. Record the time construction resumes
Negligible Impact Analysis and Determination
NMFS has defined negligible impact as an impact resulting from the
specified activity that cannot be reasonably expected to, and is not
reasonably likely to, adversely affect the species or stock through
effects on annual rates of recruitment or survival (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes alone is not enough
information on which to base an impact determination. In addition to
[[Page 72320]]
considering estimates of the number of marine mammals that might be
``taken'' through harassment, NMFS considers other factors, such as the
likely nature of any responses (e.g., intensity, duration), the context
of any responses (e.g., critical reproductive time or location,
migration), as well as effects on habitat, and the likely effectiveness
of the mitigation. We also assess the number, intensity, and context of
estimated takes by evaluating this information relative to population
status. Consistent with the 1989 preamble for NMFS's implementing
regulations (54 FR 40338; September 29, 1989), the impacts from other
past and ongoing anthropogenic activities are incorporated into this
analysis via their impacts on the environmental baseline (e.g., as
reflected in the regulatory status of the species, population size and
growth rate where known, ongoing sources of human-caused mortality, or
ambient noise levels).
Construction activities associated with this project have the
potential to disturb or displace marine mammals. No serious injury or
mortality is expected, and with mitigation we expect to avoid any
potential for Level A harassment as a result of the Seal Bend and
Minhoto-Hester Marsh construction activities. The specified activities
may result in take, in the form of Level B harassment (behavioral
disturbance) only, from visual disturbance and/or noise from
construction activities. The project area is within a portion of the
local habitat for harbor seals of the greater Elkhorn Slough and seals
are present year-round. Behavioral disturbances that could result from
anthropogenic sound or visual disturbance associated with these
activities are expected to affect only a small amount of the total
population (i.e., likely maximum of 250 seals), although those effects
could be recurring over the life of the project if the same individuals
remain in the project vicinity. Harbor seals may avoid the area or halt
any behaviors (e.g., resting) when exposed to anthropogenic noise or
visual disturbance. Due to the abundance of suitable haul out habitat
available in the greater Elkhorn Slough, the short-term displacement of
resting harbor seals is not expected to affect the overall fitness of
any individual animal.
Effects on individuals that are taken by Level B harassment, on the
basis of reports in the literature as well as monitoring from other
similar activities, will likely be limited to reactions such as
displacement from the area or disturbance during resting. The
construction activities analyzed here are similar to, or less impactful
than for Parson's Slough (and other projects), which have taken place
with no reported injuries or mortality to marine mammals, and no known
long-term adverse consequences from behavioral harassment. Repeated
exposures of individuals to levels of noise or visual disturbance at
these levels, though they may cause Level B harassment, are unlikely to
result in hearing impairment or to significantly disrupt foraging
behavior. Many animals perform vital functions, such as feeding,
resting, traveling, and socializing, on a diel cycle (i.e., 24 hour
cycle). Behavioral reactions (such as disruption of critical life
functions, displacement, or avoidance of important habitat) are more
likely to be significant if they last more than one diel cycle or recur
on subsequent days (Southall et al., 2007). However, Pacific harbor
seals have been hauling out at Elkhorn Slough during the year for many
years (including during pupping season and while females are pregnant)
while being exposed to anthropogenic sound and visual sources such as
vessel traffic, UPRR trains, and human voices from kayaking. Harbor
seals have repeatedly hauled out to rest (inside and outside the
project area) or pup (outside of the project area) despite these
potential stressors. The activities are not expected to result in the
alteration of reproductive or feeding behaviors. It is not likely that
neonates will be in the project area as females prefer to keep their
pups along the main channel of Elkhorn Slough, which is outside the
area expected to be impacted by project activities. Seals are primarily
foraging outside of Elkhorn Slough and at night in Monterey Bay,
outside the project area, and during times when construction activities
are not occurring.
Pacific harbor seals, as the potentially affected marine mammal
species under NMFS jurisdiction in the action area, are not listed as
threatened or endangered under the ESA and NMFS SARs for this stock
have shown that the population is increasing and is considered stable
(Carretta et al., 2016). Even repeated Level B harassment of some small
subset of the overall stock is unlikely to result in any significant
realized decrease in viability for the affected individuals, and thus
will not result in any adverse impact to the stock as a whole. The
restoration of the marsh habitat will have no adverse effect on marine
mammal habitat, but possibly a long-term beneficial effect on harbor
seals by improving ecological function of the slough, inclusive of
higher species diversity, increased species abundance, larger fish, and
improved habitat.
In summary and as described above, the following factors primarily
support our preliminary determination that the impacts resulting from
this activity are not expected to adversely affect the species or stock
through effects on annual rates of recruitment or survival:
No serious injury or mortality is anticipated or
authorized.
No Level A harassment is anticipated or authorized.
Anticipated incidents of Level B harassment consist of, at
worst, temporary modifications in behavior.
Primary foraging and reproductive habitat are outside of
the project area and the construction activities are not expected to
result in the alteration of habitat important to these behaviors or
substantially impact the behaviors themselves. There is alternative
haul out habitat just outside the footprint of the construction area,
along the main channel of Elkhorn Slough, and in Parson's Slough,
preferred in recent years for pupping (per comm Harvey 2019), that will
be available for seals while some of the haul outs are inaccessible.
Restoration of the marsh habitat will have no adverse
effect on marine mammal habitat, but possibly a long-term beneficial
effect.
Presumed efficacy of the mitigation measures in reducing
the effects of the specified activity to the level of least practicable
impact
These stocks are not listed under the ESA or considered
depleted under the MMPA. In combination, we believe that these factors,
as well as the available body of evidence from other similar
activities, demonstrate that the potential effects of the specified
activities will have only short-term effects on a relatively small
portion of the entire California stock (five percent). The specified
activities are not expected to impact rates of recruitment or survival
and will therefore not result in population-level impacts.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the proposed monitoring and
mitigation measures, NMFS preliminarily finds that the total marine
mammal take from the proposed activity will have a negligible impact on
all affected marine mammal species or stocks.
Small Numbers
As noted above, only small numbers of incidental take may be
authorized under Sections 101(a)(5)(A) and (D) of
[[Page 72321]]
the MMPA for specified activities other than military readiness
activities. The MMPA does not define small numbers and so, in practice,
where estimated numbers are available, NMFS compares the number of
individuals taken to the most appropriate estimation of abundance of
the relevant species or stock in our determination of whether an
authorization is limited to small numbers of marine mammals.
Additionally, other qualitative factors may be considered in the
analysis, such as the temporal or spatial scale of the activities.
Here, the authorized take (if we conservatively assumed that each
take occurred to a new animal, which is unlikely) comprises
approximately five percent of the abundance of harbor seals. Therefore,
based on the analysis contained herein of the proposed activity
(including the proposed mitigation and monitoring measures) and the
anticipated take of marine mammals, NMFS preliminarily finds that small
numbers of marine mammals will be taken relative to the population size
of the affected species or stocks.
Unmitigable Adverse Impact Analysis and Determination
There are no relevant subsistence uses of the affected marine
mammal stocks or species implicated by this action. Therefore, NMFS has
preliminarily determined that the total taking of affected species or
stocks would not have an unmitigable adverse impact on the availability
of such species or stocks for taking for subsistence purposes.
Endangered Species Act (ESA)
Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16
U.S.C. 1531 et seq.) requires that each Federal agency insure that any
action it authorizes, funds, or carries out is not likely to jeopardize
the continued existence of any endangered or threatened species or
result in the destruction or adverse modification of designated
critical habitat. To ensure ESA compliance for the issuance of IHAs,
NMFS consults internally whenever we propose to authorize take for
endangered or threatened species.
No incidental take of ESA-listed species is proposed for
authorization or expected to result from this activity. Therefore, NMFS
has determined that formal consultation under section 7 of the ESA is
not required for this action.
Proposed Authorization
As a result of these preliminary determinations, NMFS proposes to
issue an IHA to CDFW for conducting Phase II of the Elkhorn Slough
Tidal Marsh Restoration Project in Elkhorn Slough located in Monterey
County, CA over 11 months, provided the previously mentioned
mitigation, monitoring, and reporting requirements are incorporated. A
draft of the proposed IHA can be found at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.
Request for Public Comments
We request comment on our analyses, the proposed authorization, and
any other aspect of this Notice of Proposed IHA for the proposed
[action]. We also request at this time comment on the potential renewal
of this proposed IHA as described in the paragraph below. Please
include with your comments any supporting data or literature citations
to help inform decisions on the request for this IHA or a subsequent
Renewal.
On a case-by-case basis, NMFS may issue a one-year IHA renewal with
an additional 15 days for public comments when (1) another year of
identical or nearly identical activities as described in the Specified
Activities section of this notice is planned or (2) the activities as
described in the Specified Activities section of this notice would not
be completed by the time the IHA expires and a Renewal would allow for
completion of the activities beyond that described in the Dates and
Duration section of this notice, provided all of the following
conditions are met:
A request for renewal is received no later than 60 days
prior to expiration of the current IHA.
The request for renewal must include the following:
(1) An explanation that the activities to be conducted under the
requested Renewal are identical to the activities analyzed under the
initial IHA, are a subset of the activities, or include changes so
minor (e.g., reduction in pile size) that the changes do not affect the
previous analyses, mitigation and monitoring requirements, or take
estimates (with the exception of reducing the type or amount of take
because only a subset of the initially analyzed activities remain to be
completed under the Renewal).
(2) A preliminary monitoring report showing the results of the
required monitoring to date and an explanation showing that the
monitoring results do not indicate impacts of a scale or nature not
previously analyzed or authorized.
Upon review of the request for Renewal, the status of the
affected species or stocks, and any other pertinent information, NMFS
determines that there are no more than minor changes in the activities,
the mitigation and monitoring measures will remain the same and
appropriate, and the findings in the initial IHA remain valid.
Dated: December 23, 2019.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2019-28211 Filed 12-30-19; 8:45 am]
BILLING CODE 3510-22-P