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The brown booby (''Sula leucogaster'') is a large seabird of the booby family, ''Sulidae''. They present sexual dimorphism. The female booby reaches about in length, its wingspan measures up to , and they can weigh up to . The male booby reaches about in length, its wingspan measures up to , and they can weigh up to .〔Ospina-Alvarez, A. 2008. Coloniality of Brown booby (Sula leucogaster) in Gorgona National Natural Park, Eastern Tropical Pacific. Onitología Neotropical 19: 517–529.〕 The booby's head and upper body (back) is covered in dark brown or black, with the remainder (belly) being a contrasting white. The juvenile form is gray-brown with darkening on the head, wings and tail. While these birds are typically silent, bird watchers have reported occasional sounds similar to grunting or quacking. Their beaks are quite sharp and contain many jagged edges. They have short wings and long, tapered tails. This species breeds on islands and coasts in the pantropical areas of the Atlantic and Pacific oceans. They frequent the breeding grounds of the islands in the Gulf of Mexico and the Caribbean Sea. This bird nests in large colonies, laying two chalky blue eggs on the ground in a mound of broken shells and vegetation. It winters at sea over a wider area. Brown booby pairs may remain together over several seasons. They perform elaborate greeting rituals, and are also spectacular divers, plunging into the ocean at high speed. They mainly eat small fish or squid which gather in groups near the surface and may catch leaping fish while skimming the surface. Although they are powerful and agile fliers, they are particularly clumsy in takeoffs and landings; they use strong winds and high perches to assist their takeoffs. ==Subspecies== The four subspecies recognised are: * ''Sula leucogaster brewsteri'' Goss 1888 * ''Sula leucogaster etesiaca'' Thayer & Bangs 1905 * ''Sula leucogaster leucogaster'' (Boddaert) 1783 * ''Sula leucogaster plotus'' (Forster,JR) 1844 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「brown booby」の詳細全文を読む スポンサード リンク
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