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Kumlien's gull (''Larus glaucoides kumlieni'') is a large gull which breeds in the Arctic regions of Canada. It is migratory, wintering from Labrador south to New England and west across the Great Lakes. The species is named after the Swedish-American naturalist Thure Kumlien. It is a regular vagrant in small numbers to Britain and Ireland. It has variably been considered a full species, a subspecies of Thayer's gull, a subspecies of Iceland gull, and a hybrid between the aforementioned species. It is currently considered a subspecies of Iceland gull by the American Ornithologists' Union. This taxon breeds colonially or singly on coasts and cliffs, making a nest lined with grass, moss or seaweed on the ground or cliff. Normally, 2-3 light brown eggs are laid. The taxon is pale in all plumages, with a remarkably variable amount of pigment in the primaries. Individuals range from completely white-winged (indistinguishable from nominate ''glaucoides'' Iceland gull) to so dark in the wings as to be indistinguishable from Thayer's gull. Eye color is also variable, from pale yellow to dark brown. Such remarkable variation seems to lend credence to the belief that Kumlien's gull is in fact a hybrid swarm. Kumlien's gulls average smaller overall and much smaller-billed than the very large glaucous gull and are usually smaller than herring gull. The taxon reaches adult plumage in four to five years. The call is a "laughing" cry like the herring gull's, but higher pitched. These are omnivores like most ''Larus'' gulls, and they will scavenge as well as seeking suitable small prey. These birds forage while flying, picking up food at or just below the water's surface, also feeds while walking or swimming. Their scavenging habits lead them to frequent garbage dumps, sewage outlets and places where fish are cleaned. ==References== * ''Seabirds'' by Harrison, ISBN 0-7470-1410-8 * 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Kumlien's gull」の詳細全文を読む スポンサード リンク
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