One of North America's rarest geese, the Emperor goose is small and stocky, with dark bluish-gray feathers and black barring on its upperparts. Male and female are similar, the female being slightly smaller than the male. Juveniles have a slightly duller coloring than the adults, having brown barring on their upperparts, gray mottling on their head and foreneck, olive-brown legs and a black bill.
Emperor geese have a range which centers on the North Pacific Ocean in the Bering Sea. They breed in sub-Arctic and Arctic Alaska and along Russia's north-eastern coast. Most of the population winters along the Aleutian Islands' coasts, but may also winter in the Alaskan Peninsula and Canada. They inhabit open sites in arctic tundra during the mating season, either near inland lakes, coastal lagoons, or freshwater pools. In winter, they are mainly found on ice-free coasts.
Habits and lifestyle
Emperor geese in their wintering or nesting areas are relatively sedentary. Particularly when nesting, the pairs have little to do with other birds, except for defensive behavior if some other goose comes too close. During the non-migration seasons, emperor geese swim or walk much more often than they fly. They are diurnal and usually feed in their family groups, but in winter they gather in big flocks for molting. The mating adults molt in areas relatively nearby their breeding grounds, while the non-mating birds gather in large flocks at several other sites. The typical threatening actions of the emperor goose include bowing, head-jerking and wing-flapping. The female will defend only the nest site, doing so aggressively in the postures she adopts, and uttering loud calls.
flock, gaggle, skein, wedge
Diet and nutrition
Emperor geese feed mainly by grazing. They eat grasses, berries and leaves of sedges while breeding. While in wintering grounds located on rocky coasts, they eat seaweeds and algae, along with some mollusks and crustaceans.
Emperor geese are monogamous and will form a new bond only if their previous mate dies. Late May to early June is the period of the breeding season. They breed in loose colonies. Females select their nest site amongst low vegetation to have better visibility, and they build the nest on the ground, which is a shallow depression. It is lined with grass, down and feathers. Males do not participate in nesting duties, but remain nearby to defend the nest and the family against intruders. 1-8, but more commonly 5 creamy-white eggs are laid. The female incubates on her own for the 24-25 days. The chicks are precocial, usually leaving the nest on their first day of life. They can walk and swim within hours. Goslings fledge about 50-60 days after hatching and become mature at 2-3 years of age.
The Emperor goose is threatened by hunting in Russia and coastal oil pollution. Habitat loss in tundra as a result of climate change may impact negatively on this species in the very nearest future.
According to the IUCN Red List, the total population size of Emperor geese is estimated to number 85,000 individuals, while the population in Russia has been estimated at 100-10,000 breeding pairs. This species' numbers are decreasing today and it is classified as near threatened (NT) on the IUCN Red List.
In their consumption of mollusks, Emperor geese impact those populations significantly. It is thought that by grazing they increase the growth of vegetation in their habitat, therefore probably benefiting many organisms in the area that use vegetation for cover or food.
Fun facts for kids
- Emperor geese are very well adapted for swimming and they swim year round. When threatened by a land predator, their usual response is to run toward water, then swim to somewhere safer. Goslings have been seen diving when threatened by aerial predators.
- Emperor geese in flight make a raucous “kla-ha kla-ha” and a high-pitched “yang-yang”. They also quack, but they are usually are more silent than other species of goose.
- When seeking mollusks, particularly in the mud or underwater, Emperor geese mostly use their sense of touch.
- These geese rely mostly on sense of sight to identify predators or competitors, and to find food on land.
- Emperor geese fly lower than other species of goose, with faster wingbeats.
- During winter, an Emperor goose eats seaweed, mollusks and, crustaceans, especially barnacles, and so its head is stained orange-red because of iron oxide concentration in the tidal areas. This makes it look very different.