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The red grouse, ''Lagopus lagopus scotica'', is a medium-sized bird of the grouse family which is found in heather moorland in Great Britain and Ireland. It is usually classified as a subspecies of the willow ptarmigan but is sometimes considered to be a separate species, ''Lagopus scotica''. It is also known as the moorcock, moorfowl or moorbird. ==Description== The red grouse is differentiated from the willow ptarmigan and rock ptarmigan by its plumage being reddish brown, and not having a white winter plumage. The tail is black and the legs are white. There are white stripes on the underwing and red combs over the eye. Females are less reddish than the males and have less conspicuous combs. Young birds are duller and lack the red combs. Birds in Ireland are sometimes thought to belong to a separate subspecies ''L. l. hibernica''. They are slightly paler than those in Britain and the females have yellower plumage with more finely barred underparts. This may be an adaptation to camouflage them in moorland with higher grass and sedge content and less heather. It is identified by its ''chut!chut!chut!chut!chut!chuttt....'' call, or the ''Goback, goback, goback'' vocalisation. The wings make a whirring sound when the bird is disturbed from a resting place. Grouse populations display periodic cycling, where the population builds up to very high densities only to crash a few years later, and then recover. The main driver of this cyclic pattern is thought to be the parasitic nematode worm ''Trichostrongylus tenuis''. However, in his book,〔Wynne Edwards, V. C. ''Evolution through Group Selection'' 1986 Blackwell Scientific Publications Oxford〕 V. C. Wynne-Edwards suggests that the primary reason for mortality in grouse population is homeostasis depending largely on food availability and that the 'Grouse disease', due to the parasitic worm ''Trichostrongylus tenuis'' is a mistaken diagnosis of the after effects of social exclusion. 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「Red grouse」の詳細全文を読む スポンサード リンク
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