Photo: Laura L. Whitehouse/USFWS · Alaska SeaLife Center, Seward, Alaska · U.S. Fish & Wildlife Service · Public Domain
Waterfowl
Spectacled Eider
Somateria fischeri
A large sea duck named for the male's distinctive pale green 'spectacles' — large circular patches of goose-bumpy white feathers surrounding each eye, bordered by black. Listed as threatened under the U.S. Endangered Species Act. Remarkable for wintering in a single large polynya (open water surrounded by sea ice) in the Bering Sea.
Where to look
Nesting birds in western Alaska tundra; wintering aggregation in the central Bering Sea pack ice (not accessible). Small numbers pass through Aleutian waters during migration.
Habitat
Arctic and sub-Arctic tundra (breeding); open leads in pack ice (winter).
Diet
Bivalves and other benthic invertebrates.
Natural history note
Almost the entire world population of Spectacled Eiders overwinters in a single polynya in the St. Lawrence Island area of the Bering Sea — a gathering unknown to science until the 1990s.