history of non-native mammal management on kodiak national ... · u.s. fish & wildlife service...

U.S. Fish & Wildlife Service

National Wildlife Refuge System

History of Non-native Mammal

Management on Kodiak National

Wildlife Refuge McCrea Cobb, Wildlife Biologist

Kodiak National Wildlife Refuge



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



Introductions in AK •  Long history

– 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



Widespread

(Paul 2009)



Species Release 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 ~300-350 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 1952-53 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 1964-65 Kodiak Island XX Moose 1966-67 Kodiak Island XX European Wild Hog 1984 Marmot Island XX Canada Goose 1986 Shuyak Is., Spiridon 1000s



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



Sitka Black-tailed Deer •  1924, ‘30, ’34:

•  25 deer from SE AK to Long Island and Kodiak

•  1940-50s: •  Population limited to

northern Kodiak •  1960-70s:

•  Deer disperse across Kodiak



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



Feral Reindeer •  1924:

– 32 introduced to Lazy Bay, Kodiak

– Managed by Akhiok residents

•  Herd peaked at 3,000 in 1950

•  Herded until 1961 Red River 1945



Feral Reindeer •  1965-1990s:

–  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 200-500

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Lichens extirpated?

No dedicated surveys



Roosevelt Elk •  1929: 8 calves

introduced to Afognak

•  1952: •  ~300 elk and 1st hunt

•  1960: •  State assumed

management



Elk

•  1965: Population peaked at ~1,400

•  Fluctuated with winter weather

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1929 1939 1949 1959 1969 1979 1989 1999 2009

Estim

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Mountain Goats •  Successful

introduction to Baranof Island

•  Efforts to introduce goats to Kodiak began in 1948

•  1952-53: 18 goat introduced to Hidden Basin, Kodiak from Kenai Peninsula



Mountain Goats •  Slow initial

population growth •  2011: est. 2,500

mountain goats •  Population

stabilized in north •  Draw hunt

•  Increasing in south •  Registration hunt

R² = 0.98

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Cou

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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”



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



Transfer of Authority •  Alaska statehood

(1959) – State assumes

management control of introduced mammals

– First deer harvested on Refuge



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



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



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



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



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



Mountain Goat Research •  Management Goal

–  Avoid negative impacts to landscape and maintain hunting opportunities

•  Study Goals –  Determine goat diet and

feeding site selection –  Develop nutritional-

based carrying capacity model

–  Compare results among populations



Future Impacts? •  Climate change

– Milder winters •  Larger introduced

ungulate populations?

•  Greater population swings?

•  Habitat shifts and novel habitats

•  Refuges will need to adapt to a changing environment



Questions?

history of non-native mammal management on kodiak national ... · u.s. fish & wildlife service...

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