Spectacled Eider

Somateria fischeri

White goggles around the eyes and a winter range that wasn't found until 1995. Hides in plain sight on Arctic seas.

Population: ~360,000–400,000 individuals total (~250,000 mature individuals)
Habitat: Breeds on Arctic tundra wetlands (small lakes, ponds, bogs, streams, coastal marshes); non-breeding season spent at sea in ice-associated Bering, Chukchi, and Beaufort Sea waters over sandy-mud substrates, seagrass beds, and macroalgal/kelp habitats
Fun fact: Male Spectacled Eiders have a striking pale, goggle-like patch of feathers ringing each eye — the "spectacles" that give the species its name — and for decades scientists had no idea where the entire wintering population went until 1990s satellite-tag tracking revealed it packs into dense open-water leads in the pack ice of the central Bering Sea.
Range: Breeds along coastal tundra of Alaska (North Slope, Yukon-Kuskokwim Delta, ~5%+5% of population) and northeastern Siberia, Russia (Yana Delta to Cape Schmidt, ~90% of the population); winters in the Bering Sea, notably a dense concentration between St. Lawrence and St. Matthew Islands discovered via satellite tracking in the 1990s
Diet: Aquatic invertebrates — mollusks (clams) as the dominant winter/marine food (dives to depths of ~250 ft/75 m), plus aquatic insects, crustaceans, and plant material/seeds on tundra breeding grounds
Size: 0.545 m
Lifespan: 18 years

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