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The Iceland gull (''Larus glaucoides'') is a large gull which breeds in the Arctic regions of Canada and Greenland, but not Iceland, where it is only seen in the winter. It is migratory, wintering from in the North Atlantic as far south as the British Isles and northernmost states of the eastern USA, as well as in the interior of North America as far west as the western Great Lakes. It is much scarcer in Europe than the similar glaucous gull. The American taxon Kumlien's gull is often considered a subspecies, ''L. g. kumlieni'', of Iceland gull. This species 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 nominate subspecies, ''glaucoides'', is very pale in all plumages, with absolutely no melanin in the tips of the primaries in adult plumage. Adults are pale grey above, with a yellowish-green bill. Immatures are very pale grey; the bill is more extensively dark than with glaucous gull, and lacks pink. The Iceland gull is a largish gull, although relatively slender and light-weight. In length, it can measure from , wingspan is from and weight is from . Among standard measurements, the wing chord is , the bill is and the tarsus is .〔''Gulls: Of North America, Europe, and Asia'' by Klaus Malling Olsen & Hans Larsson. Princeton University Press (2004). ISBN 978-0691119977.〕〔Harrison, Peter, ''Seabirds: An Identification Guide''. Houghton Mifflin Harcourt (1991), ISBN 978-0-395-60291-1〕〔''CRC Handbook of Avian Body Masses'' by John B. Dunning Jr. (Editor). CRC Press (1992), ISBN 978-0-8493-4258-5.〕 It is smaller and thinner billed than the very large glaucous gull, and is usually smaller than the herring gull. It takes four years to reach maturity. The call is a "laughing" cry like herring gull, but higher pitched. These are omnivores like most ''Larus'' gulls, eating fish, molluscs, offal, scraps, and eggs. 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「Iceland gull」の詳細全文を読む スポンサード リンク
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