Subspecies
Monotypic species
Genus
The white geese are a small group of waterfowl which are united in the genus or subgenus Chen, in the true geese and swan subfamily Anserinae. They breed on subarctic areas of North America and around the Bering Strait, migrating south in winter. Many authorities place these species in the grey goose genus Anser. Indeed, Chen and Anser are anatomically indistinguishable. However, external morphology, biogeography, and molecular data suggest that the white geese are indeed an evolutionary lineage distinct from the grey geese ? from which they split off fairly recently, essentially replacing them in North America. The AOU recognizes this genus as distinct; most other authorities today consider it a subgenus of Anser. Like grey but unlike the Branta black geese, their feet and legs are colored in reddish hues. The bill is also reddish in these birds as in most grey geese, except in adult males of Ross’s Goose which have a blue-black grainy cere. The wingtips are black, as in all true geese, whereas the head is always white without any markings or pattern in adult birds of this genus, which distinguishes them from all other true geese except feral domesticated geese. The rest of the plumage is either white all over, or colored in various dark bluish-grey hues; the latter birds, uniquely among true geese, do not have white uppertail and undertail coverts, though the tail itself may be white. White-phase snow geese of both species can be told apart from feral geese best by the more slender, elegant neck, which is thick-set in domestic geese; these also have a generally heavier body and often lack black wingtips.
Physical charateristics
Listen to the sound of Emperor Goose
[audio:http://www.planetofbirds.com/MASTER/ANSERIFORMES/Anatidae/sounds/Emperor Goose.mp3]
Copyright remark: Most sounds derived from xeno-canto
wingspan min.: | 0 | cm | wingspan max.: | 0 | cm |
size min.: | 66 | cm | size max.: | 89 | cm |
incubation min.: | 24 | days | incubation max.: | 25 | days |
fledging min.: | 50 | days | fledging max.: | 60 | days |
broods: | 1 | eggs min.: | 3 | ||
eggs max.: | 7 |
Range
Habitat
Closely tied to salt water at all seasons. Most nesting areas on low marshy tundra within 10 miles of coast, near sloughs and rivers affected by tides. Flocks in migration stop over on large coastal estuaries. In winter, found along shorelines. Autumn st
rays south to Oregon and California may appear well inland.
Reproduction
Nest: Site on small island in pond, raised hummock or shoreline, surrounded by low dead vegetation but with good visibility. Nest is a shallow scrape lined with dead plant material and with large amounts of down.
Clutch 4-6, sometimes 2-8. Creamy white, becoming nest-stained. Females frequently lay eggs in each other’s nests. Incubation is by female only, typically 24 days, up to 27.
Young: Goslings can walk and swim within hours after hatching, usually lea
ve nest in less than a day, following parents to good feeding areas that may be several miles from nest site. Both parents tend young. Adults with broods adopt a threat posture with neck outstretched and bill pointed toward source of disturbance. Young fl
edge in 50-60 days. 1 brood per year.
Feeding habits
esh growth of sedges and other plants during summer. In late summer, may feed on crowberry or blueberry. During migration and winter feeds heavily on clams and mussels, also on marine algae and other plants.
Behavior: On breeding grounds, forages mostly on land, grubbing for roots, grazing on fresh growth. During migration and winter, forages on mudflats exposed by falling tides, walking on wet mud or in shallow water.
Video Emperor Goose
copyright: Josep del Hoyo
Conservation
Migration
Migration: Timing of migration affected by weather. In spring and fall, flocks may stage for several weeks in lagoons on north shore of Alaska Peninsula before moving on to breeding areas on west coast of Alaska or wintering areas in Aleutians.