Landbirds/ Raptors
MIGRATION
Species that share the same breeding
habitat in central Alaska travel to markedly different wintering grounds:
- Blackpoll Warblers fly south to the western Amazon Basin;
- Arctic
Warblers migrate to Southeast Asia;
- White-crowned Sparrows pass the winter in the southwestern United States; and
- Willow Ptarmigan stay in Alaska all winter.
Like many landbirds that breed in North
America, 69 species, or 51%, of landbirds that breed in Alaska migrate to Mexico,
Caribbean islands, or Central and South America. No other group of birds that
breed in Alaska, including shorebirds, contains as many species that travel outside
of the United States to spend the winter. The Bank Swallow and Peregrine
Falcon, for example, will travel as far south as Argentina.
Nine species
of landbirds (7%) that nest in Alaska and migrate to Asia in the winter breed
nowhere else in the United States. These include the Bluethroat, White Wagtail, and Northern Wheatear. Most of these species are
more widespread in Europe and Russia. Little is known about their biology in Alaska.
Some
landbird species (19%) that leave Alaska for the winter end their migration when
they reach the lower 48 states. Many of these species will spend the winter in
the coastal forests of the Pacific Northwest (e.g., Northern Saw-whet Owl, Varied Thrush, Red Crossbill). In years of short food supplies,
large numbers of Bohemian Waxwings, Northern Hawk Owls, and White-winged
Crossbills will invade the lower 48 states from Alaska.
Surprisingly,
31 landbird species (23%) choose to spend their winter in Alaska. As you might
expect, most of Alaska's winter landbird residents are grouse, owls and woodpeckers
(18 species). Away from the coast, however, birds are often hard to find. Christmas
Bird Counts in central Alaska seldom reach 20 species and are dominated by Common Ravens, Black-capped and Boreal chickadees, and Common
Redpolls. The only species unique to Alaska, the McKay's Bunting, leaves
its breeding sites on islands in the Bering Sea to pass the winter on the mainland
coast of western Alaska.
Last Updated: September 15, 2008
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