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The rough-legged buzzard (''Buteo lagopus''), also called the rough-legged hawk, is a medium-large bird of prey. It is found in Arctic and Subarctic regions of North America and Eurasia during the breeding season and migrates south for the winter.〔 It was traditionally also known as the rough-legged falcon〔 in such works as John James Audubon's ''The Birds of America''. Nests are typically located on cliffs, bluffs or in trees. Clutch sizes are variable with food availability but 3–5 eggs are usually laid.〔 These hawks hunt over open land, feeding primarily on small mammals.〔 Along with the kestrels, kites and osprey, this is one of the few birds of prey to hover regularly.〔 ==Description== This fairly large raptorial species is with wingspan ranging from .〔〔 Individuals can weigh from with females typically being larger and heavier than males.〔〔 Weights appear to increase from summer to winter in adults, going from an average of in males and from in females.〔〔 Among the members of the ''Buteo'' genus, it is sixth heaviest, the fifth longest, and the fourth longest winged.〔 Among standard measurements in adults, the wing chord is , the tail is , culmen is and the tarsus is .〔〔〔 The plumage is predominantly brown in colour and often shows a high degree of speckling.〔 A broad brown chestband is present in most plumages and a square dark carpal patch contrasting with the white under-wing is an easily identifiable characteristic in light morph individuals.〔 A wide variety of plumage patterns are exhibited in light vs. dark morphs, males vs. females and adults vs. juveniles. Extensive field experience is required to distinguish between certain plumage variations.〔 Compared to its more common nearctic and palearctic cousins, the common buzzard (''Buteo buteo'') and the red-tailed hawk (''Buteo jamaicensis''), it is slightly larger, though may be outweighed by the latter. Its feet are feathered to the toes as an adaptation to its arctic home range. Its scientific name, ''Lagopus'', is derived from Ancient Greek ''lago'' (''λαγως''), meaning "hare", and ''pous'' (''πους''), meaning "foot".〔 Its talons are relatively small, reflecting their preferred choice of prey. Distinguishing characteristics in all plumages include long white tail feathers with one or more dark subterminal bands. The wing tips are long enough to reach or extend past the tail when the animal is perched.〔 The common buzzard can be similar-looking, with a similar long-tailed shape and can be notoriously variable in plumage. The rough-legged is longer-winged and more eagle-like in appearance. The red-tailed hawk is chunkier-looking and differs in its darker head, broader, shorter wings, barring on the wings and the tail, dark leading edge to the wings (rather than black wrist patch) and has no white base to the tail. The ferruginous hawk is larger, with a bigger, more prominent bill and has a whitish comma at the wrist and all-pale tail.〔 It is the only hawk of its size (other than the very different-looking Osprey) to regularly hover over one spot, by beating its wings quickly. 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「Rough-legged buzzard」の詳細全文を読む スポンサード リンク
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