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The Chilean hawk (''Accipiter (bicolor) chilensis'') is a bird of prey species belonging to the typical hawks. It breeds in Andes forests from central Chile and western Argentina south to Tierra del Fuego, from sea level to 2,700 m altitude (though birds are rarely observed above 1,000 m). Some winter apparently in the lowlands of NW Argentina. It is sometimes considered to be a subspecies of its northern relative the bicolored hawk (''A. bicolor''), and sometimes a distinct species. The two show differences in habitat preference and have allopatric distributions. But the situation is complicated by the subspecies ''pileatus'', which is intermediate in plumage between ''bicolor'' and ''chilensis'', and has been variously assigned to either species by those that consider them distinct. ==Description== The male is 37 to 38 cm long, while the larger female measures 41 to 42 cm. The adults have black upperparts, and an ash-grey chest and abdomen with dark barring. The throat has longitudinal dark stripes and the undertail is white. The uppertail is brown with 5 or 6 dark bands. The legs are greenish yellow, and the eyes are yellow. The sexes have similar plumage. Young birds have browner upperparts with cream fringes to the feathers. The paler chest and abdomen have longitudinal stripes. The paler uppertail makes the banding more obvious. Birds are only vocal during the breeding season. While engaging in reproductive activity, its calls do not seem to differ from those of the bicoloured hawk. This has at least two rather high-pitched scolding vocalizations: a barking row of ''keh'' or ''kow'', and a woodpecker-like faster and accelerating staccato of ''kek'' calls. These are given near the nest and might announce intruders such as the scientists coming to study the birds. A series of higher-pitched ''kie'', given by a definite Chilean hawk under similar circumstances, might replace one of the above, or it might be a distinct type of call. Pairmates address each other with a squealing ''waaah'', and a soft clear whistle is apparently used by parents to communicate something to the young.〔Trejo ''et al.'' (2006)〕 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「Chilean hawk」の詳細全文を読む スポンサード リンク
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