History of Non-native Mammal Management on Kodiak National Wildlife Refuge

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1 History of Non-native Mammal Management on Kodiak National Wildlife Refuge McCrea Cobb, Wildlife Biologist Kodiak National Wildlife Refuge

2 Why introduce new animals? New source of protein and sport hunting easier rugs and roasts should be available and in more places improving on a paradise of game Domesticated species Food for other introduced animals

3 Long history Introductions in AK Russians introduced foxes to islands in mid-1700s. Peaked in the 1920s AK Game Commission (1925) FWS took lead in 1940 State control in 1959

4 Widespread (Paul 2009)

5 U.S. Species Fish & Wildlife Release Service Date Release Site Current Status Sitka Black-tailed Deer 1887,1930, 1934 Long & Kodiak Island ~50-80,000 (?) Black Bear c.1922 Spruce Island XX Reindeer 1924 Alitak Bay ~ Muskrat 1925 NE Kodiak, Afognak (Chiniak Bay) Roosevelt Elk 1929 Afognak Island ~600 (2011) Beaver 1925 & 1929 Kodiak & Raspberry Is. ~30-50,000 (?) Snowshoe Hare 1934 Kodiak & Afognak Is. ~100,000 (?) Raccoon pre-1936 & 1980 Long & Kodiak Islands Likely XX Mountain Goat Hidden Basin, Kodiak ~2,500 (2011) Marten 1952 Afognak Island ~2-3,000 (?) Mink 1952 Kodiak Island (Karluk) XX Red Squirrel 1952 Afognak & Kodiak Is. ~10-15,000 (?) Ground Squirrel? Kodiak? 1000s Spruce Grouse 1957 & 1959 Woody Island XX Dall Sheep Kodiak Island XX Moose Kodiak Island XX European Wild Hog 1984 Marmot Island XX

6 Irruptive Population Growth General trend in growth similar across many introduced populations Limited predation Abundant resources Examples of this pattern worldwide New Zealand thar Kaibab deer

7 Sitka Black-tailed Deer 1924, 30, 34: 25 deer from SE AK to Long Island and Kodiak s: Population limited to northern Kodiak s: Deer disperse across Kodiak

8 Sitka Deer (1980s current) Population limited by winter conditions High mortality during cold, wet, long winters Harvests average ~8,000/year ~50-80,000 deer

9 Red River 1945 U.S. Fish & Wildlife Service 1924: Feral Reindeer 32 introduced to Lazy Bay, Kodiak Managed by Akhiok residents Herd peaked at 3,000 in 1950 Herded until 1961

10 s: Declared feral Open season and no bag limit 2002: same-day-airborne hunting approved 2009: Same-day airborne prohibited Reclassified as caribou with goal of Estimated Abundance Feral Reindeer Lichens extirpated? No dedicated surveys

11 Roosevelt Elk 1929: 8 calves introduced to Afognak 1952: ~300 elk and 1 st hunt 1960: State assumed management

12 Elk 1965: Population peaked at ~1,400 Fluctuated with winter weather Estimted Population Size

13 Mountain Goats Successful introduction to Baranof Island Efforts to introduce goats to Kodiak began in : 18 goat introduced to Hidden Basin, Kodiak from Kenai Peninsula

14 Mountain Goats Slow initial population growth 2011: est. 2,500 mountain goats Population stabilized in north Draw hunt Increasing in south Registration hunt Minimum Count R² = 0.98

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16 Kodiak Refuge Founded 1941 To protect the native feeding and breeding grounds of the brown bear and other wildlife Accompanying letter with executive order: provide a natural environment for other forms of wildlife such as elk, reindeer, deer, snowshoe hares, and fur animals such as beaver and muskrat

17 Early management (1940s- 1950s) Law enforcement and maintaining populations Conservative hunting regs and access allowed rapid growth Evidence of impacts to landscape Browse surveys on Afognak and Kodiak road system

18 Transfer of Authority Alaska statehood (1959) State assumes management control of introduced mammals First deer harvested on Refuge

19 Refuge Goals Refined ANILCA (1980) Conserve fish and wildlife population in their natural diversities Provide opportunities for continued subsistence uses for local residents Comprehensive Conservation Plans

20 Comprehensive Conservation Plan (1987) Natural integrity Apparent naturalness Exotic species introduction not permitted Not native to N.A. Management of introduced species not explicitly stated

21 Refuge Research Estimating Deer Abundances and Impacts Scan surveys, aerial hairpile surveys, pellet surveys, FLIR surveys, coastal surveys, alpine surveys, browse surveys Mt. Goat surveys

22 Comprehensive Conservation Plan (2006) Manage nonnative species to minimize impacts on native resources, while continuing to provide opportunities for harvest Provide the opportunity for local residents to continue their subsistence use on the Refuge, consistent with the subsistence priority and with other refuge purposes

23 Introduced Species Workshop (2000) Interagency meeting Priorities defined Complete vegetation map Study effects of deer and hare on browse Study effects of mountain goats on alpine plant communities

24 Mountain Goat Research Management Goal Avoid negative impacts to landscape and maintain hunting opportunities Study Goals Determine goat diet and feeding site selection Develop nutritionalbased carrying capacity model Compare results among populations

25 Climate change Milder winters Future Impacts? Larger introduced ungulate populations? Greater population swings? Habitat shifts and novel habitats Refuges will need to adapt to a changing environment

26 Questions?