Aleutian Canada Goose

Branta canadensis leucopareia

Description

The Aleutian Canada goose (Branta canadensis leucopareia ) is a smaller subspecies of the common Canada goose. Its length is 22-43 in (56-109 cm). Plumage is brownish gray above, and the head and neck are black with a white "chin strap." The breast is paler brown and undertail feathers are white. Nearly all Aleutian geese have a white ring at the base of the neck.

The Aleutian race is characterized by an abrupt forehead, cheek patches separated by black feathers, and a narrow, dark border beneath the white neck ring. It is difficult to differentiate the Aleutian Canada goose from similar subspecies such as the cackling Canada goose (B. c. minima ), although a cackler generally has darker edgings on its breast feathers, giving it a slightly darker appearance than an Aleutian.

Behavior

Because breeding areas in the Aleutian Islands are remote, the Aleutian Canada goose has not been studied extensively. In most respects it is similar to other subspecies of Canada geese. The Aleutian is gregarious in nonbreeding season, often gathering in flocks of several hundred. It is thought to mate for life, with ganders defending mates from other males. The nesting season varies according to latitude and weather. The female lays a clutch of about six eggs and incubates them for 28 days. As soon as the chicks hatch, the mother leads them to water. The family group swims together with the gander leading and the mother bringing up the rear.

The Aleutian feeds on marsh vegetation, eel grass, and algae. During migration it has been known to glean harvested grain fields. In the breeding season it feeds on water plants, insects, and crustaceans.

Habitat

On the islands where they breed, Aleutian Canada geese prefer inland areas such as meadows and marshes but will also nest near inlets and bushy areas by the sea. When migrating, they frequent marshes, meadows, and grain fields where they feed on corn and other grains left behind by mechanical harvesting techniques.

Distribution

Aleutian Canada geese once bred from the eastern Aleutian Islands to the Kuril Islands and were most abundant in the western Aleutians. The original breeding range included most of the larger Aleutian Islands from the Islands of Four Mountains to Attu and Bering islands. Aleutian Canada geese historically wintered in Japan and in North America (from British Columbia to California).

The main breeding population of Aleutian Canada geese, estimated at about 300 breeding pairs in 1982, is on Buldir Island in the western Aleutian chain. A remnant breeding population of unknown size was discovered in June 1982 on Chagulak Island in the Islands of Four Mountains. Aleutians now winter mostly in California. The largest recorded number, about 2,700 birds, was seen in California in 1981 and was more than triple the 1975 population count.

Breeding populations of Aleutian Canada geese have been reestablished on Agattu, Nizki, and Amchitka islands.

Threats

The major cause of Aleutian goose decline was the introduction of Arctic foxes (Alopex lagopus ) into the breeding range by the Russian-American Company during the 1830s.

Conservation and Recovery

Buldir Island, the main breeding island today, is one of the few Aleutian Islands without a fox population. The geese have also been hunted by humans while nesting, during migration in Alaska, and on their wintering grounds. Some Aleutian geese were domesticated by the island natives. In 1965 the Aleutian Islands National Wildlife Refuge staff completed a program to eliminate foxes from Amchitka Island. Since then, foxes have been eliminated on Agattu, and trapping programs were initiated on the islands of Alaid, Nizki, and Kanaga.

Various attempts to breed Aleutian Canada geese for reintroduction to the wild produced mixed results. In 1971 the first release of captive-bred geese on Amchitka failed to establish a breeding population. In 1974, 41 captive-bred geese were moved to the western Aleutians and released on Agattu Island. Four pairs nested, two successfully, and five goslings hatched. Two of these tagged geese were recaptured in California later the same year.

In 1980, in an attempt to improve reproductive success, wild adult males captured on Buldir were paired with adult captive-reared females. The pairs were allowed to produce and raise their own young at propagation facilities on Amchitka Island. Natural young were supplemented with foster young, and during the winter of 1980-1981, 18 migrated south to Oregon and California. Using another reintroduction strategy, naturalists captured 60 wild geese on Buldir and released them on Agattu to establish a breeding population there.

Because of rising costs and the mixed success of captive-breeding, all captive Aleutian geese were released on Agattu in 1982, and the captive-breeding program was phased out. Only wild birds are now used in transplantation efforts.

An encouraging year for the recovery effort was 1987. It was confirmed that relocated birds were indeed returning to Agattu to breed—a major milestone. For the first time in decades Aleutian geese were found nesting on Nizki Island, site of a 1981 release of captive-reared birds. Field biologists have relocated 60 adults and 76 goslings from Buldir to Amchitka Island, hoping to establish yet another breeding population there.

Contacts

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N.E. 11th Ave.
Portland, Oregon 97232-4181
(503) 231-6121
http://pacific.fws.gov/

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
1011 E. Tudor Rd., Room 135
Anchorage, Alaska 99503
Telephone: (907) 786-3909
Fax: (907) 786-3844
http://alaska.fws.gov/

References

Bent, A. C. 1912. "Notes on Birds Observed during a Brief Visit to the Aleutian Islands and Bering Sea in 1911." Smithsonian Miscellaneous Collection 56 (32):1-29.

Jones, R. D. 1963. "Buldir Island, Site of a Remnant Breeding Population of Aleutian Canada Geese." Wildfowl Trust Annual 14: 80-84.

Temple, S. A., ed. 1978. Endangered Birds: Management Techniques for Preserving Threatened Species. University of Wisconsin Press, Madison.

U. S. Fish and Wildlife Service. 1982. "The Aleutian Canada Goose Recovery Plan." U. S. Fish and Wildlife Service, Anchorage.