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 a