eWestern BirdsThe Quarterly Journal of Western Field Ornithologists
Vol. 43, No. 4
Western Field Ornithologists
Geographic Variation in Wintering Greater White-fronted Geese
Richard C. Banks
ABSTRACT: There is relatively little variation in size, expressed mainly in bill dimensions, between or among most wintering populations of the Greater White-fronted Goose (Anser albifrons). In the British Isles, slightly larger and darker birds, from the Greenland breeding population, winter in Ireland and Scotland and associated islands, while smaller birds winter in England. Winter birds in continental Europe are the same size as those in England. Asian winter birds average slightly larger than those of Europe; the population is more variable and includes some larger individuals. In western North America, some birds in the Sacramento Valley of northern California, the famed Tule Goose (A. a. elgasi), are the largest of the species. There is a great range of variation in smaller birds of the Sacramento Valley and elsewhere in the west coast states. Birds in the midcontinent states, east of the Rocky Mountains, average about the same as smaller California birds but vary widely.