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The bateleur (''Terathopius ecaudatus'') is a medium-sized eagle in the family ''Accipitridae''. Its closest relatives are the snake eagles. It is the only member of the genus ''Terathopius'' and may be the origin of the "Zimbabwe Bird", national emblem of Zimbabwe.〔(【引用サイトリンク】title=Zimbabwe Bird )〕 It is endemic to Africa and small parts of Arabia. "''Bateleur''" is French for "Street Performer".〔(【引用サイトリンク】title=bateleur translation English - French dictionary - Reverso )〕 ==Description and Behavior== The average adult is long with a wingspan. The wing chord averages approximately . Adult weight is typically .〔J. M. Mendelsohn, A. C. Kemp, H. C. Biggs, R. Biggs & C. J. Brown(1989) ''WING AREAS, WING LOADINGS AND WING SPANS OF 66 SPECIES OF AFRICAN RAPTORS'' Ostrich, Vol. 60, No.1, p.35-60〕 The bateleur is a colourful species with a very short tail (''ecaudatus'' is Latin for tailless) which, together with its white underwing coverts, makes it unmistakable in flight. The tail is so small the bird's legs protrude slightly beyond the tail during flight. The bateleur is sexually dimorphic; both adults have black plumage, a chestnut mantle and tail, grey shoulders, tawny wing coverts, and red facial skin, bill and legs. The female additionally has tawny secondary wing feathers. Less commonly, the mantle may be white.〔Newman, K (1998) Newman's Birds of Southern Africa. Halfway House: Southern Book Publishers. ISBN 1868127680.〕 Immature birds are brown with white dappling and have greenish facial skin. It takes them seven or eight years to reach full maturity. The bateleur is diurnal, and hunts over a territory of approximately a day. Bateleurs are hunters and scavengers; birds such as pigeons and sandgrouse are preferred prey items, although it may attack small mammals and also takes carrion. The bateleur is generally silent, but on occasions it produces a variety of barks and screams. The bird spends a considerable amount of time on the wing, particularly in low-altitude glides.〔Kemp, AC & Begg KS 2001. Comparison of time-activity budgets and population structure for 18 large-bird species in the Kruger National Park, South Africa. Ostrich, Vol.72, No.3-4, p.179-184〕 "''Bateleur''" is French for "street performer" 〔 which included performers such as tight-rope walkers. This name implies the bird’s characteristic habit of rocking its wings from side to side when gliding, as if catching its balance. The bateleur breeds in December–March. It constructs a well-concealed nest in trees, laying a single egg which is incubated by the female for 42 to 43 days, with a further 90 to 125 days until fledging. Bateleurs pair for life, and will use the same nest for a number of years. Unpaired birds, presumably from a previous clutch, will sometimes help at the nest. Bateleur eagles are among a group of raptors that secrete a clear, salty fluid from their nares whilst eating. According to Schmidt-Nielson's (1964) hypothesis, this is due to the general necessity for birds to use an extrarenal mechanism of salt secretion to aid water reabsorption.〔Cade, T.J. and L. Greenwald 1964. Nasal Salt Secretion in Falconiform Birds. The Condor, Vol.68, No.4, p.338-350〕 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「bateleur」の詳細全文を読む スポンサード リンク
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