[Federal Register Volume 85, Number 17 (Monday, January 27, 2020)]
[Notices]
[Pages 4696-4699]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-01326]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

[FWS-R8-ES-2019-N045; FF08EVEN00-FXES111608MSSO0]


Marine Mammal Protection Act; Stock Assessment Report for the 
Southern Sea Otter in California

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of availability; request for comments.

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SUMMARY: In accordance with the Marine Mammal Protection Act of 1972, 
as amended, we, the U.S. Fish and Wildlife Service, have developed a 
draft revised marine mammal stock assessment report for the southern 
sea otter stock in the State of California. We now make the draft stock 
assessment report available for public review and comment.

DATES: We will consider comments that are received or postmarked on or 
before April 27, 2020.

ADDRESSES: Document availability: If you wish to review the draft 
revised stock assessment report for southern sea otter, you may obtain 
a copy from our website at http://www.fws.gov/ventura. Alternatively, 
you may contact the Ventura Fish and Wildlife Office, 2493 Portola 
Road, Suite B, Ventura, CA 93003 (telephone: 805-644-1766).
    Comment submission: If you wish to comment on the draft stock 
assessment report, you may submit your comments in writing by any one 
of the following methods:
     U.S. mail: Field Supervisor, at the above address;
     Hand delivery: Ventura Fish and Wildlife Office at the 
above address;
     Fax: 805-644-3958; or
     Email: [email protected].

FOR FURTHER INFORMATION CONTACT: Lilian Carswell, at the above street 
address, by telephone (805-677-3325), or by email 
([email protected]). Persons who use a telecommunications device 
for the deaf (TDD) may call the Federal Relay Service at 800-877-8339.

SUPPLEMENTARY INFORMATION: We announce the availability for review and 
comment of a draft revised marine mammal stock assessment report (SAR) 
for the southern sea otter (Enhydra lutris nereis) stock in the State 
of California.

Background

    Under the Marine Mammal Protection Act of 1972, as amended (MMPA; 
16 U.S.C. 1361 et seq.), and its implementing regulations in the Code 
of Federal Regulations (CFR) at 50 CFR part 18, the U.S. Fish and 
Wildlife Service (Service) regulates the taking; import; and, under 
certain conditions, possession; transportation; purchasing; selling; 
and offering for sale, purchase, or export, of marine mammals. One of 
the MMPA's goals is to ensure that stocks of marine mammals occurring 
in waters under U.S. jurisdiction do not experience a level of human-
caused mortality and serious injury that is likely to cause the stock 
to be reduced below its optimum sustainable population level (OSP). OSP 
is defined under the MMPA as ``the number of animals which will result 
in the maximum productivity of the population or the species, keeping 
in mind the carrying capacity of the habitat and the health of the 
ecosystem of which they form a constituent element'' (16 U.S.C. 
1362(9)).
    To help accomplish the goal of maintaining marine mammal stocks at 
their OSPs, section 117 of the MMPA requires the Service and the 
National Marine Fisheries Service (NMFS) to prepare a SAR for each 
marine mammal stock that occurs in waters under U.S. jurisdiction. A 
SAR must be based on the best scientific information available; 
therefore, we prepare it in consultation with regional scientific 
review groups established under section 117(d) of the MMPA. Each SAR 
must include:
    1. A description of the stock and its geographic range;
    2. A minimum population estimate, current and maximum net 
productivity rate, and current population trend;
    3. An estimate of the annual human-caused mortality and serious 
injury by source and, for a strategic stock, other factors that may be 
causing a decline or impeding recovery;
    4. A description of commercial fishery interactions;
    5. A categorization of the status of the stock; and
    6. An estimate of the potential biological removal (PBR) level.
    The MMPA defines the PBR 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 OSP'' (16 
U.S.C. 1362(20)). The PBR is the product of the minimum population 
estimate of the stock (Nmin); one-half the maximum 
theoretical or estimated net productivity rate of the stock at a small 
population size (Rmax); and a recovery factor 
(Fr) of between 0.1 and 1.0, which is intended to compensate 
for uncertainty and unknown estimation errors. This can be written as:

PBR = (Nmin)(\1/2\ of the Rmax)(Fr)

    Section 117 of the MMPA also requires the Service and NMFS to 
review the SARs (a) at least annually for stocks that are specified as 
strategic stocks, (b) at least annually for stocks for which 
significant new information is available, and (c) at least once every 3 
years for all other stocks. If our review of the status of a stock 
indicates that it has changed or may be more accurately determined, 
then the SAR must be revised accordingly.
    A strategic stock is defined in the MMPA as a marine mammal stock 
``(a) for which the level of direct human-caused mortality exceeds the 
PBR level; (b) which, based on the best available scientific 
information, is declining and is likely to be listed as a threatened 
species under the Endangered Species Act of 1973, as amended (16 U.S.C. 
1531 et seq.) [the ``ESA''], within the foreseeable future; or (c) 
which is listed as a threatened or endangered species under the ESA, or 
is designated as depleted under [the MMPA].'' 16 U.S.C. 1362(19).

Stock Assessment Report History for the Southern Sea Otter in 
California

    The southern sea otter SAR was last revised in 2017. Because the 
southern sea otter is listed as a threatened species under the ESA, the 
stock is considered strategic. Therefore, the Service reviews the stock 
assessment annually. In 2018, Service review concluded that revision 
was not warranted because the status of the stock had not changed, nor 
could it be more accurately determined. However, upon review in 2019, 
the Service determined that revision was warranted because the status 
of the stock may be subject to change. The range-wide population index 
(i.e., population level over a consecutive 3-year period) reached the 
ESA threshold (i.e., exceeding 3,090 animals) for delisting 
consideration identified in the Southern Sea Otter Recovery Plan (U.S. 
Fish and Wildlife Service 2003). As a result, the Service will initiate 
an ESA status review to determine whether delisting of the southern sea 
otter is appropriate, which could result in a

[[Page 4697]]

change to the status of the stock under the MMPA.

Summary of Draft Revised Stock Assessment Report for the Southern Sea 
Otter in California

    The following table summarizes some of the information contained in 
the draft revised southern sea otter SAR, which includes the stock's 
Nmin, Rmax, Fr, PBR, annual estimated 
human-caused mortality and serious injury, and status. After 
consideration of any public comments we receive, the Service will 
revise and finalize the SAR, as appropriate. We will publish a notice 
of availability and summary of the final SAR, including responses to 
submitted comments.

                Summary--Draft Revised Stock Assessment Report, Southern Sea Otter in California
----------------------------------------------------------------------------------------------------------------
                                                                       Annual estimated human-
    Southern sea otter stock       NMIN      RMAX       FR      PBR     caused  mortality and     Stock status
                                                                           serious injury
----------------------------------------------------------------------------------------------------------------
Mainland.......................     2,986      0.06      0.1     9.24  Figures by specific     Strategic.
                                                                        source, where known,
                                                                        are provided in the
                                                                        SAR.
San Nicolas Island.............        95      0.13      0.1     0.62
Summary........................     3,081  ........  .......        9
----------------------------------------------------------------------------------------------------------------

Public Availability of Comments

    Before including your address, phone number, email address, or 
other personal identifying information in your comment, you should be 
aware that your entire comment--including your personal identifying 
information--may be made publicly available at any time. While you can 
ask us in your comment to withhold your personal identifying 
information from public review, we cannot guarantee that we will be 
able to do so.

References

    In accordance with the MMPA, we include in this notice a list of 
the information sources and public reports upon which we based the SAR:

Babcock, E.A., E.K. Pikitch, and C.G. Hudon. 2003. How much observer 
coverage is enough to adequately estimate bycatch? Pew Institute for 
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Bacon, C.E., W.M. Jarman, J.A. Estes, M. Simon, and R.J. Norstrom. 
1999. Comparison of organochlorine contaminants among sea otter 
(Enhydra lutris) populations in California and Alaska. Environ. 
Toxicology and Chemistry 18:452-458.
Barlow, J. 1989. Estimating sample size required to monitor marine 
mammal mortality in California gillnet fisheries. Southwest 
Fisheries Science Center Administrative Report LJ-89-08, 8 pp.
Bentall, G.B. 2005. Morphological and behavioral correlates of 
population status in the southern sea otter: A comparative study 
between central California and San Nicolas Island. Master's Thesis, 
University of California, Santa Cruz, CA, unpublished.
Burge, C.A., C.M. Eakin, C.S. Friedman, B. Froelich, P.K. 
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Willis, SE Ford, and C.D. Harvell. 2014. Climate change influences 
on marine infectious diseases: Implications for management and 
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Bryant, H.C. 1915. Sea otters near Point Sur. California Department 
of Fish and Game Bulletin. 1:134-135.
Cameron, G.A. and K.A. Forney. 2000. Preliminary estimates of 
cetacean mortality in California/Oregon gillnet fisheries for 1999. 
Paper SC/S2/O24 presented to the International Whaling Commission, 
2000 (unpublished), 12 pp. Available from NMFS, Southwest Fisheries 
Science Center, P.O. Box 271, La Jolla, CA 92038.
Carretta, J.V. 2001. Preliminary estimates of cetacean mortality in 
California gillnet fisheries for 2000. Paper SC/53/SM9 presented to 
the International Whaling Commission, 2001 (unpublished), 21 pp. 
Available from NMFS, Southwest Fisheries Science Center, P.O. Box 
271, La Jolla, CA 92038.
Chinn, S.M., M.A. Miller, M.T. Tinker, M.M. Staedler, F.I. Batac, 
E.M. Dodd, L.A. Henkel. 2016. The high cost of motherhood: End-
lactation syndrome in southern sea otters. Journal of Wildlife 
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toxoplasma: Clues from the study of sea otters as sentinels of 
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1996. Mitochondrial-DNA variation among subspecies and populations 
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[[Page 4698]]

and territories of male sea otters off central California. Marine 
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the Washington sea otter population. Unpublished report, 5 pp.
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M.A. Miller, D.A. Jessup and J.A.K. Mazet. 2009. Prey choice and 
habitat use drive sea otter pathogen exposure in a resource-limited 
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perfluorinated compounds and pathological conditions in southern sea 
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Authority

    The authority for this action is the Marine Mammal Protection Act 
of 1972, as amended (16 U.S.C. 1361 et al.)

    Dated: January 8, 2020.
Aurelia Skipwith,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2020-01326 Filed 1-24-20; 8:45 am]
 BILLING CODE 4333-15-P