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The fulvous whistling duck or fulvous tree duck (''Dendrocygna bicolor'') is a whistling duck that breeds across the world's tropical regions in much of Mexico and South America, the West Indies, the southern US, sub-Saharan Africa and the Indian subcontinent. It has mainly reddish brown plumage, long legs and a long grey bill, and shows a distinctive white band across its black tail in flight. Like other members of its ancient lineage, it has a whistling call which is given in flight or on the ground. The preferred habitat is shallow lakes, paddy fields or other wetlands with plentiful vegetation. The nest, built from plant material and unlined, is placed among dense vegetation or in a tree hole. The typical clutch is around ten whitish eggs. The breeding adults, which pair for life, take turns to incubate, and the eggs hatch in 24–29 days. The downy grey ducklings leave the nest within a day or so of hatching, but the parents continue to protect them until they fledge around nine weeks later. The fulvous whistling duck feeds in wetlands by day or night on seeds and other parts of plants. It is sometimes regarded as a pest of rice cultivation, and is also shot for food in parts of its range. Despite hunting, poisoning by pesticides and natural predation by mammals, birds and reptiles, the large numbers and huge range of this duck mean that it is classified as Least Concern by the International Union for Conservation of Nature (IUCN). ==Taxonomy== The whistling ducks, ''Dendrocygna'', are a distinctive group of eight bird species within the duck, goose and swan family Anatidae, which are characterised by a hump-backed, long-necked appearance and the whistled flight calls that give them their English name.〔Madge & Burn (1988) p. 124.〕 They were an early split from the main duck lineage,〔Feduccia (1999) p. 219.〕 and were predominant in the Late Miocene before the subsequent extensive radiation of more modern forms in the Pliocene and later. The fulvous whistling duck forms a superspecies with the wandering whistling duck. It has no recognised subspecies, although the birds in northern Mexico and the southern US have in the past been assigned to ''D. b. helva'',〔 〕 described as having paler and brighter underparts and a lighter crown than ''D. b. bicolor''. The duck was first described by Johann Friedrich Gmelin in 1789 and given the name ''Anas fulva'' but the name was "preoccupied," or already used, by Friedrich Christian Meuschen in 1787 for another species. This led to the next available name proposed by French ornithologist Louis Jean Pierre Vieillot in 1816 from a Paraguayan specimen as ''Anas bicolor''〔Vieillot (1816) (pp. 136–137 ).〕 The whistling ducks were moved to their current genus, ''Dendrocygna'', by British ornithologist William John Swainson in recognition of their differences from other ducks.〔Swainson (1837) (p. 365 ).〕 The genus name is derived from the Ancient Greek ''dendron'', "tree", and Latin ''cygnus'', "swan",〔Jobling (2010) pp. 128,133.〕 and '' bicolor'' is Latin for "two-coloured".〔Jobling (2010) p. 72.〕 "Fulvous" means reddish-yellow, and is derived from the Latin equivalent ''fulvus''. Old and regional names include large whistling teal,〔 brown tree duck, Mexican duck, squealer and Spanish cavalier.〔 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「Fulvous whistling duck」の詳細全文を読む スポンサード リンク
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