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The laughing gull (''Leucophaeus atricilla'') is a medium-sized gull of North and South America. It breeds on the Atlantic coast of North America, the Caribbean, and northern South America. Northernmost populations migrate further south in winter, and this species occurs as a rare vagrant to western Europe. (There was an influx into North-west Europe in late October 2005 when at least 18, possibly as many as 35, individuals occurred on one day in the UK alone.) The laughing gull's English name is derived from its raucous ''kee-agh'' call, which sounds like a high-pitched laugh "ha... ha... ha...". This species is easy to identify. It is long with a wingspan. The summer adult's body is white apart from the dark grey back and wings and black head. Its wings are much darker grey than all other gulls of similar size except the smaller Franklin's gull, and they have black tips without the white crescent shown by Franklin's. The beak is long and red. The black hood is mostly lost in winter. There are two subspecies: *''L. a. megalopterus'' – (Bruch, 1855): West Indies to Venezuelan islands *''L. a. atricilla'' – (Linnaeus, 1758): coastal southeast Canada, eastern & southern USA, Mexico & Central America Laughing gulls take three years to reach adult plumage. Immature birds are always darker than most similar-sized gulls other than Franklin's. First-year birds are greyer below and have paler heads than first-year Franklin's, and second-years can be distinguished by the wing pattern and structure. Laughing gulls breed in coastal marshes and ponds in large colonies. The large nest, made largely from grasses, is constructed on the ground. The 3 or 4 greenish eggs are incubated for about three weeks. These are omnivores like most gulls, and they will scavenge as well as seeking suitable small prey. Like most other members of the genus ''Leucophaeus'', the laughing gull was long placed in the genus ''Larus''. The present placement in ''Leucophaeus'' follows the American Ornithologists' Union. ==Various views and plumages== Image:Laughing Gull - mating plumage.jpg|Mating plumage includes black head and red bill image:Larus atricilla1.jpg|Definitive alternate plumage image:Flying Laughing Gull.jpg|Adult in mid-May (definitive alternate plumage) image:Laughing Gull first plumage.jpg|first basic plumage Image:Laughing Gulls on sand.jpg|Adult in winter (definitive basic plumage) Image:Laughing Gull juvenile.jpg|Juvenile Image:Laughing gull St Thomas.JPG|Adult at St. Thomas, Virgin Islands (definitive alternate plumage) Image:Laughing gull Porthmadog.jpg|Vagrant in definitive basic plumage in the UK in late 2005 Image:Caneel Bay Seagulls By Caneel Beach 15.jpg|Preparing to land on beach Image:Guanaguanre (Larus atricilla) de los Roques Venezuela 000.jpg|Los Roques Venezuela File:Larus atricilla MWNH 0343.JPG|Egg, Collection Museum Wiesbaden 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「Laughing gull」の詳細全文を読む スポンサード リンク
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