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The tchagras are passerine birds in the bushshrike family, which are closely related to the true shrikes in the family Laniidae, and were once included in that group. These five species form the genus ''Tchagra'' within the bushshrike family: * Marsh tchagra, ''Tchagra minuta'' * Black-crowned tchagra, ''Tchagra senegala'' * Brown-crowned tchagra or brown-headed tchagra, ''Tchagra australis'' * Three-streaked tchagra, ''Tchagra jamesi'' * Southern tchagra, ''Tchagra tchagra'' The marsh tchagra is sometimes placed in the monotypic genus ''Antichromus'', and then named as blackcap bushshrike. The dark Angolan subspecies of marsh tchagra was formerly sometimes split as Anchieta's tchagra, ''Tchagra anchietae'', named after Portuguese explorer José Alberto de Oliveira Anchieta by his zoologist compatriot José Vicente Barbosa du Bocage in 1869. These are long-tailed birds, typically with a grey or grey-brown back, brown wings and grey and whitish underparts. The head pattern is distinctive, with a dark cap and black eyestripe separated by a white supercilium. The bill is strong and hooked. The male and female are similar in plumage in all Tchagra species, but distinguishable from immature birds. These are solitary birds which tend to skulk low down or on the ground. They have distinctive whistled calls and can be readily tempted into sight by imitating the call, presumably because the Tchagra is concerned that there is an intruder in its territory. These are species typically of scrub, open woodland, semi-desert and cultivation in sub-Saharan Africa. They hunt large insects from a low perch in a bush, and the larger species like black-crowned tchagra will also take vertebrate prey such as frogs and snakes. == References == * Barlow, Wacher and Disley, ''Birds of The Gambia'' ISBN 1-873403-32-1 * Tony Harris and Kim Franklin, ''Shrikes and Bush-Shrikes'' ISBN 0-7136-3861-3 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「Tchagra」の詳細全文を読む スポンサード リンク
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