White-fronted Goose
From Wikipedia, the free encyclopedia
| iWhite-fronted Goose | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 |
||||||||||||||
|
|
||||||||||||||
| Scientific classification | ||||||||||||||
|
||||||||||||||
|
|
||||||||||||||
| Anser albifrons (Scopoli, 1769) |
||||||||||||||
|
|
||||||||||||||
|
The White-fronted Goose (Anser albifrons) is a goose closely related to the smaller Lesser White-fronted Goose (A. erythropus). In North America it is known as the Greater White-fronted Goose.
Both white-fronted species have a very conspicuous white face and broad black bars which cross the belly, though the last two characters are occasionally observable to some extent in the Greylag Goose, which, however, has the bill and legs flesh-coloured, and pale bluish-grey upper wing-coverts. In Northern and Central North America, the Greater Whitefront is colloquially called 'Specklebelly' due to the salt-and-pepper appearance of the underside.
White-fronts are 65-78 cm in length and have a 130-165 cm wingspan. They have bright orange legs and mouse-coloured upper wing-coverts. They are smaller than Greylag Geese. As well as being larger than the Lesser White-fronted Goose, the Greater Whitefront lacks the yellow eye-ring of that species, and the white facial blaze does not extend upwards so far as in Lesser.
The Greater Whitefront is divided into five subspecies. The nominate subspecies A. a. albifrons breeds in the far north of Europe and Asia, and winters further south and west in Europe. In the far east of Siberia east to arctic Canada, it is replaced by A. a. frontalis, slightly larger and with a marginally longer bill, wintering in the United States and Japan.
Two other restricted-range races occur slightly further south in northern North America; A. a. gambeli in interior northwest Canada, slightly larger still and wintering on the U.S. Gulf Coast, and the doubtfully distinct (Carboneras, 1992) A. a. elgasi (Tule Goose) in southwest Alaska, largest and longest-billed of all, wintering in California. All these races are similar in plumage, differing only in size.
Finally, the very distinct Greenland White-fronted Goose A. a. flavirostris breeding in western Greenland, is much darker overall, with only a very narrow white tip to the tail (broader on the other races), more black barring on its belly, and usually has an orange (not pink) bill. It winters in Ireland and western Scotland.
Recent ecological studies suggest the Greenland birds should probably be considered a separate species from A. albifrons (Fox & Stroud 2002). Of particular interest is its unusually long period of parental care and association, which may last several years and can include grandparenting, possibly uniquely among the Anseriformes.
In the British Isles, two races overwinter: Greenland birds in Scotland and Ireland, and Russian birds in England and Wales. They gather on farmland at favoured traditional sites, with a famous flock gathering at WWT Slimbridge, Gloucestershire, England.
A.a.albifrons and A.a.flavirostis are among the species to which the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) applies.
 Walking on ice |
 Illustration from Hume and Marshall's Gamebirds of India, Burmah and Ceylon |
[edit] References
- BirdLife International (2004). Anser albifrons. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 11 May 2006. Database entry includes justification for why this species is of least concern
- Carboneras, Carles (1992): Family Anatidae (Ducks, Geese and Swans). In: del Hoyo, Josep; Elliott, Andrew & Sargatal, Jordi (editors): Handbook of Birds of the World, Volume 1: Ostrich to Ducks: 536-629. Lynx Edicions, Barcelona. ISBN 84-87334-10-5
- Fox, A. D. & Stroud, D. A. (2002): Greenland White-fronted Goose. Birds of the Western Palearctic Update 4(2): 65-88.
[edit] External links
