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The southern yellow-billed hornbill (''Tockus leucomelas'') is a hornbill found in southern Africa. Yellow-billed hornbills feed mainly on the ground, where they forage for seeds, small insects, spiders and scorpions. This hornbill is a common, widespread resident of the dry thorn fields and broad-leafed woodlands. They can often be seen along roads and rivers. == Description == It is a medium-sized bird, in length, in weight and is characterized by a long yellow and down-curved beak. This beak is huge in comparison to its body and can account for up 1/6th of the entire body length. Male beaks are on average 90mm long while female beaks are have an average of 74 mm. Males are generally bigger than females but there is overlap between the 2 sexes. The size difference of the beak is a fairly reliable way of differentiating sex in wild hornbills. The casque that characterizes all hornbills is of a very modest size in the southern yellow-billed hornbill. It is small, but it covers almost the entire length of the beak giving the impression that they do not actually have a casque. As in all hornbills, the size of the beak actually intrudes on the frontal vision of the bird and the first two neck vertebrae are fused together.〔 Also like most other hornbills, they possess a long tail, long eyelashes, stubby legs and stubby toes. The front three toes are fused together at the base.〔 They have a white belly, grey neck, and black back with abundant white spots and stripes. The neck has gray spots and the chest is lightly striated with black. Southern yellow-billed hornbills have no pigmentation save for melanin, which can only produce shades of black and white.〔 The eyes are usually yellow, though brown has also been seen.The skin around the eyes and in the malar stripe is pinkish. The related eastern yellow-billed hornbill from north-eastern Africa has blackish skin around the eyes. 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「Southern yellow-billed hornbill」の詳細全文を読む スポンサード リンク
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