Tuesday, January 29, 2008

Snow Goose (Chen caerulescens)


Family: Anatidae

Habitat: Tundra and other open areas, usually near bodies of fresh water or salt-water marshes. Often forages in pasturelands, cultivated fields, and flooded farmlands.

Distribution: Breeding range extends from northern Alaska east along the Arctic coast and islands to northwestern Greenland and Baffin Island, and south to Hudson Bay. Winters in the west from coastal British Columbia south to California, Baja California, southwestern Arizona, and Mexico; in the mid-West from Nebraska, Iowa and the Great Lakes south to the Gulf Coast; and in the east along the Atlantic coast from New York south to Florida (A.O.U. 1998).

Field Marks: Black primary feathers. Two color phases: a blue phase and a white phase. In adult birds, note the thick, black 'grinning patch' that separates the upper and lower mandibles; compare with Ross' Goose. Adults have pink bills whereas the bills of immatures are darker.

Nest Habits: Breeds on the ground, in colonies; nest is a depression lined with mosses, grasses, and down feathers.

Eggs: 1-8, usually 3-5; 80 millimeter; white in color.

Incubation: Incubation lasts approximately 23-25 days, by female. Young are able to fly when they are approximately 45-49 days old; both sexes care for the young.

Greater White-fronted Goose (Anser albifrons)


Family: Anatidae

Habitat: Open areas, arctic tundra, usually near water; in winter and migration, also frequents pastures and flooded agricultural fields.

Distribution: Breeding range extends from Alaska eastward across northern Yukon, Mackenzie, and Keewatin to western Greenland. Winter range in the west extends from southern British Columbia south to Baja California; in the mid-west, from Texas and Louisiana north to Oklahoma and Kansas; and in the eastern U.S. from the Great Lakes region south to Mississippi and Florida (A.O.U. 1998).

Field Marks: Key field marks include the black speckling on the belly, the pink bill bordered with white at the base, and the orange legs and feet.

Nest Habits: Breeds in loose colonies on open tundra.

Eggs: 1-7, usually 5-6; 79 millimeter; buffy-white or cream-colored.

Incubation: The female incubates the eggs; both sexes care for the young. Incubation lasts approximately 23-25 days and the young are capable of flight when they are about 45 days old.