great auk: see auk.

auk, common name for a member of the family Alcidae (alcid family), swimming and diving birds of the N Atlantic and Pacific, which includes the guillemots and puffins. Their legs are set far back on their bodies, making them clumsy on land, where they seldom venture except to nest. The extinct, flightless great auk, Pinguinus impennis, or garefowl, represents the largest species. It was about the size of a goose, black above and grayish white below, and was formerly abundant in the N Atlantic. Slaughtered in its breeding grounds for its flesh, feathers, and oil, it became extinct c.1844. The least auklet (about 61/2 in./16.3 cm), common in the Bering Sea region, is the smallest of the family, and the razor-billed auk, Alca torda (16-18 in./40-45 cm), is the largest surviving member. The Eskimos hunt the dovekie (Plautus alle), or little auk, for food and use its feathered skin for clothing. Auks return to the same breeding grounds every year, and each individual goes to the very same nesting site. The single egg is laid on bare rock on cliff ledges, and incubation duties are shared by both parents. Auks are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Charadriiformes, family Alcidae.

Flightless seabird (Pinguinus impennis) extinct since 1844. Great auks bred in colonies on rocky islands off North Atlantic coasts; fossil remains have been found as far south as Florida, Spain, and Italy. Their bodies were about 30 in. (75 cm) long; the wings, used for swimming underwater, were less than 6 in. (15 cm) long. They stood erect on land and had a black back and head, a white front, and a large white spot between the eye and the black bill. Great auks were hunted to extinction for food and bait. About 80 specimens are preserved in museums. Seealso auk.

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In general, any of 22 species of diving birds (family Alcidae), especially the little auk and the razorbill, or razor-billed auk. Auks are 6–16 in. (15–40 cm) long, with short wings and legs and webbed feet. They occur only in Arctic, subarctic, and temperate regions (with a few species south to Baja California). Auks nest colonially on cliff ledges or in rock crevices or burrows near the sea; many spend the winter far from land. They feed on fish, crustaceans, mollusks, and plankton. True auks are black and white and stand erect on land. Seealso great auk.

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