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The Trocaz pigeon, Madeira laurel pigeon or long-toed pigeon (''Columba trocaz'') is a pigeon which is endemic to the island of Madeira. It is a mainly grey bird with a pinkish breast; its silvery neck patch and lack of white wing markings distinguish it from its close relative and probable ancestor, the common wood pigeon. Its call is a characteristic six-note cooing, weaker and lower-pitched than that of the wood pigeon. Despite its bulky, long-tailed appearance, this pigeon has a fast, direct flight. A scarce resident breeder in laurisilva forests, the Trocaz pigeon lays one white egg in a flimsy twig nest. Its numbers fell sharply after human colonisation of the Madeira archipelago, and it vanished altogether from Porto Santo Island. The major cause of its population decline was habitat loss from forest clearance, but hunting and nest predation by introduced rats were also contributory factors. Protection of the laurel forests and a ban on hunting have enabled numbers to increase, so that the species is no longer endangered. ==Description== The Trocaz pigeon is a rather plain, dark grey bird long with a wingspan.〔 The upper back has a violet sheen, becoming green on the back of the neck, and the neck sides are patterned with silver-white. The tail is blackish with a wide, pale grey band, and the flight feathers are mainly black. The upper breast is pinkish, the eye is yellow, the bill has a yellow tip and a reddish-purple base, and the legs are red. The sexes are similar in appearance, but the juvenile has generally browner plumage, with limited or no development of the silvery neck patch. Its closed wings have a scaly appearance due to pale buff feather edges.〔 The Trocaz pigeon's voice is weaker and deeper than that of common wood pigeon, typically consisting of six syllables with the middle pair of notes extended and stressed: ''uh-uh hrooh-hrooh ho-ho''.〔Mullarney (1999) p. 216.〕 When flying, it appears heavy and large-tailed, although its flight is rapid and direct.〔 The common wood pigeon had a poorly defined Madeiran subspecies, ''Columba palumbus maderensis''. This was paler than the Trocaz pigeon and had white wing patches and a more extensive green iridescence on the nape,〔 but it became extinct before 1924. Bolle's pigeon is more similar in appearance to the Trocaz pigeon, although it lacks the whitish neck patch and has a more extensively pink breast. However, that species is endemic to the Canary Islands, so there is no range overlap.〔 The only other pigeon currently present on Madeira is the feral pigeon; this is slimmer, has more pointed wings and a much smaller tail. It often has dark wing markings, and a lighter flight.〔 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「Trocaz pigeon」の詳細全文を読む スポンサード リンク
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