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:''"Buteo melanoleucus" redirect here. This name is also the name that the black-and-white hawk-eagle (''Spizaetus melanoleucus'') was first described under; see below for details.'' The black-chested buzzard-eagle (''Geranoaetus melanoleucus'') is a bird of prey of the hawk and eagle family (Accipitridae). It lives in open regions of South America. This species is also known as the black buzzard-eagle, grey buzzard-eagle or analogously with "eagle" or "eagle-buzzard" replacing "buzzard-eagle", or as the Chilean blue eagle. It is sometimes placed in the genus ''Buteo''.〔〔 ==Description== This is a huge eagle-like "buzzard" ("hawk" in American terminology). It has a total length of and a wingspan of .〔Blake, E. R. 1977. ''Manual of neotropical birds. Volume 1''. University of Chicago Press, Chicago, Illinois.〕〔Bierregaard, R.O 1994. Black-chested Buzzard-eagle Geranoaetus melanoleucus. Page 175 in J. del Hoyo, A. Elliott, and J. Sargatal (editors), Handbook of the birds of the world. Volume 2. Lynx Edicions, Barcelona.〕 In the nominate race, males averaged and females averaged , with a range between both of .〔Jiménez, J.E., and F.M. Jaksíc. 1990. ''Historia natural del aguila Geranoaetus melanoleucus: una revision''. Hornero 13: 97-110.〕 In the linearly slightly smaller ''G. m. australis'' subspecies, a male weighed and a female weighed , indicating the bulk of the two races is roughly the same.〔''CRC Handbook of Avian Body Masses, 2nd Edition'' by John B. Dunning Jr. (Editor). CRC Press (2008), ISBN 978-1-4200-6444-5.〕〔(Black-chested Eagle-buzzard (''Geranoaetus melanoleucus'') ). raptorfoundation.org.uk〕 It is noted for its bulky, powerful-looking build. It is rather long- and broad-winged and the slightly tapering tail is short by comparison and colored black, with grey tips in fresh plumage. When perched, the wings cover the tail almost completely, giving the bird a unique near-tailess appearance when perched. The adult has a white underside, sometimes with fine blackish stripes; its upperparts are dark grey with a blackish, brownish or bluish hue. The feathers of the neck and the lowest dark feathers of the breast are somewhat elongated. Adults have an ash-grey-and-white zone on the wings, the silvery white seen clearly from afar. The female is distinguished by a reddish-cinnamon hue to the upper- and underwing secondaries〔(Black Chested Buzzard Eagle ). gochile.cl〕 and is considerably larger than the male.〔〔 Among standard measurements, males possess a wing chord of , a tail of , a culmen of and a tarsus of . In comparison, females have a wing chord of , a tail of , a culmen of and a tarsus of .〔 The immature plumage is reminiscent of that of the great black hawk (''Buteogallus urubitinga''). Its upperparts are deep brown, sometimes almost black, and it has no light wing patch. The underside is white or light buff with heavy dark streaks on the breast and dark bars on the belly and thighs. It does not acquire the full adult plumage until 4–5 years old.〔〔〔 It is not very vocal, calling usually in flight and when close to the nest. Some calls resemble a wild human laugh, others are a curlew-like whistle.〔 Occasionally flying birds give a high-pitched vocalization "kukukukuku".〔 The black-chested buzzard-eagle is readily identified in flight by its short wedge-shaped tail scarcely protruding from its long, broad wings. It is usually easy to make out the generally white underparts with the dark chest-band and tail if the birds are adult. Yet as this bird is usually encountered in the wild when it soars, you are less likely to see its grey upperparts. 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「Black-chested buzzard-eagle」の詳細全文を読む スポンサード リンク
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