Emperor goose

Chen canagica

Photo by Reginald David (Hawaii Biological Survey)

Common name:
emperor goose (en); ganso-imperador (pt); oie empereur (fr); ganso emperador (es); kaisergans (de)

Taxonomy:
Order Anseriformes
Family Anatidae

Range:
This species is only found around the Bering Sea, breeding both along the western coast of Alaska and along the eastern coast of extreme north-eastern Russia. They migrate south to winter along the ice-free coasts of the Aleutian islands, the Alaska Peninsula and the northernmost Pacific coast of Canada.

Size:
These birds are 66-69 cm long and weigh up to 3 kg.

Habitat:
The emperor goose breeds in coastal saltmarshes and tundra grasslands near lakes and rivers. Outside the breeding season they move into ice-free coastal areas, including beaches, cliffs, dunes and reefs.

Diet:
They feed mainly on intertidal vegetation and invertebrates. The vegetation includes beach rye, crowberries, beach pea, sandwort, seaweeds, eelgrass and sea lettuce. Their animal prey are mostly blue mussels and Macoma clams, but also some crustaceans. They also eat sedges and bulbs.

Breeding:
Emperor geese breed in May-August. They are monogamous and mate for life. The female builds the nest, a scrape on the ground lined with dead vegetation. There she lays 3-8 eggs which are she incubates alone for 24-25 days. The chicks fledge 50-60 days after hatching, but remain with the parents for a long period, often returning to the breeding grounds with the parents the following spring. They start breeding at 3-4 years of age.

Conservation:
IUCN status - NT (Near-Threatened)
This species has a relatively large breeding range. The population is Alaska was estimated at 84.500 individuals, while in Russia there are possibly 100-10.000 individuals. The population is suspected to have suffered a moderately rapid decline, mainly due to subsistence hunting and the effects of oil pollution. Climate change is expected to impact negatively on the tundra habitat on which they depend for breeding, with a modelled loss of 54% of their habitat expected until 2070.

beach rye, crowberries, beach pea, and sandwort. They are also known to eat seaweed, eelgrass, and sea lettuce. While emperor geese may eat crustaceans, they mainly consume bivalves. During the spring and autumn months their diet consists primarily of blue mussels and macoma clams.