[Federal Register Volume 85, Number 17 (Monday, January 27, 2020)]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-01326]
DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
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.
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
Fax: 805-644-3958; or
FOR FURTHER INFORMATION CONTACT: Lilian Carswell, at the above street
address, by telephone (805-677-3325), or by email
(Lilian_Carswell@fws.gov). 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
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.
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
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
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
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
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
Mainland....................... 2,986 0.06 0.1 9.24 Figures by specific Strategic.
source, where known,
are provided in the
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.
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
Ocean Science and Oceana, 36 pp.
Bacon, C.E. 1994. An ecotoxicological comparison of organic
contaminants in sea otters among populations in California and
Alaska. M.S. thesis, University of California, Santa Cruz.
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.
Hershberger, E.E. Hofmann, L.E. Petes, K.C. Prager, E. Weil, B.L.
Willis, SE Ford, and C.D. Harvell. 2014. Climate change influences
on marine infectious diseases: Implications for management and
society. Annual Review of Marine Science 6:249-277.
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
Diseases 52:307-318. doi: 10.7589/2015-06-158.
Conrad, P.A., M.A. Miller, C. Kreuder, E.R. James, J. Mazet, H.
Dabritz, D.A. Jessup, F. Gulland, M.E. Grigg. 2005. Transmission of
toxoplasma: Clues from the study of sea otters as sentinels of
Toxoplasma gondii flow into the marine environment. International
Journal for Parasitology 35:1155-1168.
Cronin, M.A., J. Bodkin, B. Bellachey, J.A. Estes, and J.C. Patton.
1996. Mitochondrial-DNA variation among subspecies and populations
of sea otters (Enhydra lutris). Journal of Mammalogy 77:546-557.
Dubey, J.P., N.L. Miller, and D.K. Frenkel. 1970. Toxoplasma gondii
life cycle in cats. Journal of the American Veterinary Medical
Estes, J.A. 1990. Growth and equilibrium in sea otter populations.
J. Anim. Ecol. 59:385-401.
Estes, J.A. and R.J. Jameson. 1988. A double-survey estimate for
sighting probability of sea otters in California. Journal of
Wildlife Management 52:70-76.
Estes, J.A., B.B. Hatfield, K. Ralls, and J. Ames. 2003. Causes of
mortality in California sea otters during periods of population
growth and decline. Marine Mammal Science 19:198-216.
Forney, K.A., S.R. Benson, and G.A. Cameron. 2001. Central
California gill net effort and bycatch of sensitive species, 1990-
1998. Pages 141-160 in Seabird Bycatch: Trends, Roadblocks, and
Solutions, E.F. Melvin and J.K. Parrish, eds. Proceedings of an
International Symposium of the Pacific Seabird Group, University of
Alaska Sea Grant, Fairbanks, Alaska, 212 pp.
Gazeau, F., L.M. Parker, S. Comeau, J.-P. Gattuso, W.A. O'Connor, S.
Martin, H.-O. P[ouml]rtner, and P.M. Ross. 2013. Impacts of ocean
acidification on marine shelled molluscs. Marine Biology 160:2207-
Gerber, L.R., M.T. Tinker, D.F. Doak, J.A. Estes, and D.A. Jessup.
2004. Mortality sensitivity in life-stage simulation analysis: A
case study of southern sea otters. Ecological Applications 14:1554-
Hatfield, B.B. and J.A. Estes. 2000. Preliminary results of an
evaluation of the potential threat to sea otters posed by the
nearshore finfish trap fishery. Unpublished, 6 pp. + appendices.
Hatfield, B.B., J.L. Yee, M.C. Kenner, J.A. Tomoleoni, and M.T.
Tinker. 2018. California sea otter (Enhydra lutris nereis) census
results, spring 2018. U.S. Geological Survey Data Series 1097. 10
Hatfield, B.B., J.A. Ames, J.A. Estes, M.T. Tinker, A.B. Johnson,
M.M. Staedler, and M.D. Harris. 2011. Sea otter mortality in fish
and shellfish traps: Estimating potential impacts and exploring
possible solutions. Endangered Species Research 13:219-229.
Herrick, S.F. Jr. and D. Hanan. 1988. A review of California
entangling net fisheries, 1981-1986. National Oceanic and
Atmospheric Administration Technical Memorandum. National Marine
Fisheries Service. NOAA-TM-NMFS-SWFC-108, 39 pp.
Jameson, R.J. 1989. Movements, home range,
and territories of male sea otters off central California. Marine
Mammal Science 5:159-172.
Jameson, R.J. and S. Jeffries. 1999. Results of the 1999 survey of
the Washington sea otter population. Unpublished report, 5 pp.
Jameson, R.J. and S. Jeffries. 2005. Results of the 2005 survey of
the reintroduced Washington sea otter population. Unpublished
report, 6 pp.
Jessup D.A., M.A. Miller, M. Harris, B.B. Hatfield, and J.A. Estes.
2004. The 2003 southern sea otter (Enhydra lutris nereis) unusual
mortality event: A preliminary report to NOAA and USFWS. Unpublished
report, 38 pp.
Johnson, C.K., M.T. Tinker, J.A. Estes, P.A. Conrad, M. Staedler,
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
coastal system. PNAS 106:2242-2247.
Kannan, K., E. Perrotta, and N.J. Thomas. 2006. Association between
perfluorinated compounds and pathological conditions in southern sea
otters. Environmental Science & Technology 40:4943-4948.
Kannan, K., E. Perrotta, N.J. Thomas, and K.M. Aldous. 2007. A
comparative analysis of polybrominated diphenyl ethers and
polychlorinated biphenyls in southern sea otters that died of
infectious diseases and noninfectious causes. Archives of
Environmental Contamination and Toxicology 53:293-302.
Kannan K., K.S. Guruge, N.J. Thomas, S. Tanabe, J.P. Giesy. 1998.
Butyltin residues in southern sea otters (Enhydra lutris nereis)
found dead along California coastal waters. Environmental Science
and Technology 32:1169-1175.
Kooyman, G.L. and D.P. Costa. 1979. Effects of oiling on temperature
regulation in sea otters. Yearly progress report, Outer Continental
Shelf Energy Assessment Program.
Kreuder, C., M.A. Miller, D.A. Jessup, L.J. Lowenstein, M.D. Harris,
J.A. Ames, T.E. Carpenter, P.A. Conrad, and J.A.K. Mazet. 2003.
Patterns of mortality in southern sea otters (Enhydra lutris nereis)
from 1998-2001. Journal of Wildlife Diseases 39:495-509.
Kreuder, C., M.A. Miller, L.J. Lowenstine, P.A. Conrad, T.E.
Carpenter, D.A. Jessup, and J.A.K. Mazet. 2005. Evaluation of
cardiac lesions and risk factors associated with myocarditis and
dilated cardiomyopathy in southern sea otters (Enhydra lutris
nereis). American Journal of Veterinary Research 66:289-299.
Kroeker, K.J., R.L. Kordas, R.N. Crim, and G.G. Singh. 2010. Meta-
analysis reveals negative yet variable effects of ocean
acidification on marine organisms. Ecology Letters 13:1419-1434.
Kudela, R.M., J.Q. Lane, W.P. Cochlan. 2008. The potential role of
anthropogenically derived nitrogen in the growth of harmful algae in
California, USA. Harmful Algae 8:103-110.
Kurihara, H. and Y. Shirayama. 2004. Effects of increased
atmospheric CO2 on sea urchin early development. Marine
Ecology Progress Series 274:161-169.
Kurihara, H., T. Asai, S. Kato, and A. Ishimatsu. 2008. Effects of
elevated pCO2 on early development in the mussel Mytilus
galloprovincialis. Aquatic Biology 4:225-233.
Lafferty, K.D. and M.T. Tinker. 2014. Sea otters are recolonizing
southern California in fits and starts. Ecosphere 5:50. http://dx.doi.org/10.1890/ES13-00394.1.
Laidre, K.L., R.J. Jameson, and D.P. DeMaster. 2001. An estimation
of carrying capacity for sea otters along the California coast.
Marine Mammal Science 17:294-309.
Larson, S., R. Jameson, J. Bodkin, M. Staedler, and P. Bentzen.
2002. Microsatellite DNA and mitochondrial DNA variation in remnant
and translocated sea otter (Enhydra lutris) populations. Journal of
Mayer, K.A., M.D. Dailey, and M.A. Miller. 2003. Helminth parasites
of the southern sea otter Enhydra lutris nereis in central
California: Abundance, distribution, and pathology. Diseases of
Aquatic Organisms 53:77-88.
Miller, M.A., M.E. Grigg, C. Kreuder, E.R. James, A.C. Melli, P.R.
Crosbie, D.A. Jessup, J.C. Boothroyd, D. Brownstein, and P.A.
Conrad. 2004. An unusual genotype of Toxoplasma gondii is common in
California sea otters (Enhydra lutris nereis) and is a cause of
mortality. International Journal for Parasitology 34:275-284.
Miller, M.A., I.A. Gardner, C. Kreuder, D.M. Paradies, K.R.
Worcester, D.A. Jessup, E. Dodd, M.D. Harris, J.A. Ames, A.E.
Packham, and P.A. Conrad. 2002. Coastal freshwater runoff is a risk
factor for Toxoplasma gondii infection of southern sea otters
(Enhydra lutris nereis). International Journal for Parasitology
Miller, M.A., W.A. Miller, P.A. Conrad, E.R. James, A.C. Melli, C.M.
Leutenegger, H.A. Dabritz, A.E. Packham, D. Paradies, M. Harris, J.
Ames, D.A. Jessup, K. Worcester, M.E. Grigg. 2008. Type X Toxoplasma
gondii in a wild mussel and terrestrial carnivores from coastal
California: New linkages between terrestrial mammals, runoff and
toxoplasmosis of sea otters. International Journal for Parasitology
Miller, M.A., R.M. Kudela, A. Mekebri, D. Crane, S.C. Oates, M.T.
Tinker, M. Staedler, W.A. Miller, S. Toy-Choutka, C. Domink, D.
Hardin, G. Langlois, M. Murray, K. Ward and D.A. Jessup. 2010.
Evidence for a novel marine harmful algal bloom: Cyanotoxin
(Microcystin) transfer from land to sea otters. PLoS ONE 5:e12576.
Monson, D.H., J.A. Estes, J.L. Bodkin, and D.B. Siniff. 2000. Life
history plasticity and population regulation in sea otters. Oikos
Mos, L. 2001. Domoic acid: A fascinating marine toxin. Environmental
Toxicology and Pharmacology 9:79-85.
Nakata, H., K. Kannan, L. Jing, N. Thomas, S. Tanabe, and J.P.
Giesy. 1998. Accumulation pattern of organochlorine pesticides and
polychlorinated biphenyls in southern sea otters (Enhydra lutris
nereis) found stranded along coastal California, USA. Environmental
Ralls, K., T.C. Eagle, and D.B. Siniff. 1996. Movement and spatial
use patterns of California sea otters. Canadian Journal of Zoology
Sanchez, M.S. 1992. Differentiation and variability of mitochondrial
DNA in three sea otter, Enhydra lutris, populations. M.S. Thesis,
University of California Santa Cruz.
Siniff, D.B., T.D. Williams, A.M. Johnson, and D.L. Garshelis. 1982.
Experiments on the response of sea otters, Enhydra lutris, to oil
contamination. Biological Conservation 2: 261-272.
Stumpp, M., J. Wren, F. Melzner, M.C. Thorndyke, and S.T. Dupont.
2011. CO2 induced seawater acidification impacts on sea
urchin larval development I: Elevated metabolic rates decrease scope
for growth and induce developmental delay. Comparative Biochemistry
and Physiology, Part A: Molecular & Integrative Physiology 160:331-
Taylor, B.L., M. Scott, J. Heyning, and J. Barlow. 2003. Suggested
guidelines for recovery factors for endangered marine mammals. NOAA
Technical Memorandum NOAA-TM-NMFS-SWFSC-354.
Tinker, M.T. 2014. Models and sea otter conservation. Pp. 257-300 in
Larson, S., G. VanBlaricom and J. Bodkin, eds., Sea Otter
Conservation. New York: Elsevier.
Tinker, M.T., and B.B. Hatfield. 2016. California sea otter (Enhydra
lutris nereis) census results, spring 2016. U.S. Geological Survey
Data Series 1018. 10 pp. http://dx.doi.org/10.3133/ds1018.
Tinker, M.T., G. Bentall, and J.A. Estes. 2008a. Food limitation
leads to behavioral diversification and dietary specialization in
sea otters. PNAS 105:560-565.
Tinker, M.T., D.F. Doak, and J.A. Estes. 2008b. Using demography and
movement behavior to predict range expansion of the southern sea
otter. Ecological Applications 18:1781-1794.
Tinker, M.T., B.B. Hatfield, M.D. Harris, and J.A. Ames. 2016.
Dramatic increase in sea otter mortality from white sharks in
California. Marine Mammal Science 32:309-326.
Tinker, M.T., J.A. Estes, K. Ralls, T.M. Williams, D. Jessup, and
D.P. Costa. 2006a. Population Dynamics and Biology of the California
Sea Otter (Enhydra lutris nereis) at the Southern End of its Range.
MMS OCS Study 2006-07. Coastal Research Center, Marine Science
Institute, University of California, Santa Barbara, California. MMS
Cooperative Agreement Number 14-35-0001-31063.
Tinker, M.T., D.F. Doak, J.A. Estes, B.B. Hatfield, M.M. Staedler,
and J. Bodkin. 2006b. Incorporating diverse data and realistic
complexity into demographic estimation procedures for sea otters.
Ecological Applications 16:2293-2312.
Tinker, M.T., D. Jessup, M. Staedler, M. Murray, M. Miller, T.
Burgess, E. Bowen, K. Miles, J. Tomoleoni, N. Thometz, L. Tarjan, E.
Golson, F. Batac, E. Dodd, E.
Berberich, J. Kunz, G. Bentall, T. Nicholson, S. Newsome, H.
MacCormick, A. Melli, A. Johnson, L. Henkel, C. Kreuder-Johnson, and
P. Conrad. 2013. Sea otter population biology at Big Sur and
Monterey California: Investigating the consequences of resource
abundance and anthropogenic stressors for sea otter recovery. Draft
Final Report to California Coastal Conservancy and U.S. Fish and
Wildlife Service. University of California, Santa Cruz, 243 pp.
U.S. Fish and Wildlife Service. 2003. Final Revised Recovery Plan
for the Southern Sea Otter (Enhydra lutris nereis). Portland,
Oregon, xi + 165 pp.
U.S. Fish and Wildlife Service. 2015. Southern Sea Otter (Enhydra
lutris nereis) 5-Year Review: Summary and Evaluation. Ventura,
California. 42 pp.
Valentine, K., D.A. Duffield, L.E. Patrick, D.R. Hatch, V.L. Butler,
R.L. Hall, and N. Lehman. 2008. Ancient DNA reveals genotypic
relationships among Oregon populations of the sea otter (Enhydra
lutris). Conservation Genetics 9:933-938.
Vezie, C., J. Rapala, J. Vaitomaa, J. Seitsonen, and K. Sivonen.
2002. Effect of nitrogen and phosphorus on growth of toxic and
nontoxic Microcystis strains and on intracellular microcystin
concentrations. Microbial Ecology 43:443-454.
Walther, G.-R, E. Post, P. Convey, A. Menzel, C. Parmesank, T.J.C.
Beebee, J.-M. Fromentin, O. Hoegh-Guldberg, and F. Bairlein. 2002.
Ecological responses to recent climate change. Nature 416:389-395.
Wendell, F.E., R.A. Hardy, and J.A. Ames. 1986. An assessment of the
accidental take of sea otters, Enhydra lutris, in gill and trammel
nets. California Department of Fish and Game, Mar. Res. Tech. Rep.
No. 54, 31 pp.
Wilson, D.E., M.A. Bogan, R.L. Brownell, Jr., A.M. Burdin, and M.K.
Maminov. 1991. Geographic variation in sea otters, Enhydra lutris.
Journal of Mammalogy 72:22-36.
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.
Director, U.S. Fish and Wildlife Service.
[FR Doc. 2020-01326 Filed 1-24-20; 8:45 am]
BILLING CODE 4333-15-P