Recolonization by sea otters, Enhydra lutris, as a source of change in Southeast Alaska

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1 Recolonization by sea otters, Enhydra lutris, as a source of change in Southeast Alaska PVOA Zac Hoyt, Ginny L. Eckert, PhD Sunny Rice Petersburg and Juneau, School of Fisheries and Ocean Sciences University of Alaska Fairbanks

2 Outline Background A) History of sea otter in AK, Southeast AK, and finally southern Southeast AK.

3 Outline Background A) History of sea otter in AK, Southeast AK, and finally southern Southeast AK. B) Current distribution and population growth in southern Southeast, AK.

4 Outline Background A) History of sea otter in AK, Southeast AK, and finally southern Southeast AK. B) Current distribution and population growth in southern Southeast, AK. C) Resource competition in Southeast AK.

5 Ecological, economic & social changes as a result of sea otter recolonization in southern SE AK ADF&G fisheries statistics Movement/ Telemetry data Foraging data Sea otter abundance health data Sea otter distribution

6 Foraging, health, diet, mortality, population estimates & movement studies

7 Alaska and the sea otter resource 1741 Vitus Bering and Aleksei Chirikov made the first European landing in Alaska and SE Alaska Alexander Baranov late 1700 s

8 Aleut and Kodiak hunters

9 Population of sea otters ranged from 200, ,000 pre fur trade

10 London sea otter fur market sales 1911 worldwide moratorium on sea otter harvest, worldwide population 1,000 2,000 individuals Decline reflects dwindling sea otter populations Source: Brass E. (1911) Aus dem Reiche der Pelze, Bd III, Berlin

11 2000 sea otters in 1911

12 Alaska Sea Otter Demographics Surviving remnant populations in Alaska post Translocation by the Alaska Department of Fish and Game

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15 1988 2,167 otters Jameson 1989

16 2003 5,845 otters,6.6% annual increase since 1988 Esslinger and Bodkin 2009

17 2010 ~ 13,000 otters,~13% annual increase since 2003

18 Sea otters are a keystone predator Important for maintaining species richness

19 Fisheries affected in southern SE AK - value $21 million dollar ( ) Dungeness Crab, Metacarcinus magister (formerly Cancer magister) Red Sea Urchin, Strongylocentrotus franciscanus California Sea Cucumber, Parastichopus californicus Geoduck Clam, Panopea abrupta

20 Resource Conflicts

21 Resolutions from: Petersburg City Council Wrangell City Council Craig City Council and Tribal Association Ketchikan City Council Kake Tribal Association Southeast Alaska Regional Dive Fisheries Association Southeast Regional Subsistence Council Southeast Conference 111th Congress by Congressman Don Young Amendment to the Marine Mammal Protection Act

22 Currently commercially viable No longer commercially viable

23 Sea otter persistence and viability of the commercial Dungeness crab fishery appear spatially correlated

24 Tebenkof Bay Dive Fisheries

25 Tebenkof Bay CA Sea Cucumber Fishery Estimated Biomass of CA sea cucumbers Commercial Harvest of CA sea cucumbers 2011 USFS Wilderness Patrols Summer otters 950 otters in 2010

26 Conclusion The sea otter population is growing exponentially in southern SE AK. Reduced effort in the Dungeness crab fisheries is spatially and temporally correlated with sea otter persistence. Otters are having an impact on the regions dive fisheries.

27 Impacts of this changing ecosystem Community impacts Consolidation of Dungeness crab fleet Reduced processing in Craig, Petersburg and Wrangell Reduced subsistence and sport opportunities Increased effort in sea otter industry garment Changing ecosystems, changing opportunities Herring fisheries

28 PERMITS : MMPA permit # IACUC Special Thanks Icicle Seafood's Dr. Tim Tinker USGS / UCSC Kake Tribal USFS - Petersburg Ranger District Sean Larson Bonnie Greenwood Stena Troyer Christina Buck Tory Wilson Marlene Wagner Sharon Tsetong Aria Peterman Crew of the F/V s and R/V s: Kuprenof, Kamalar, Kestrel, Westerly, Deco Bay