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The Ural owl (''Strix uralensis'') is a medium-sized nocturnal owl of the genus ''Strix'', with up to 15 subspecies found in Europe and northern Asia. The Ural owl is smaller than the great grey owl, and much larger than the tawny owl, which it superficially resembles. Distinguishing features apart from the size are the pale, buffish grey-brown plumage, with copious dark brown streaking on the back, back of the head and underparts. It has a round head with plain buffish-grey facial discs, orange-yellow bill and small black eyes. The tail is long and wedge-shaped, with dark barring on the uppertail, and the wings are rounded. Flight is direct and purposeful, recalling that of the common buzzard. Sexes are similar, with no seasonal variation. Length can range and wingspan from . Weight in males is and in females is .〔''CRC Handbook of Avian Body Masses'' by John B. Dunning Jr. (Editor). CRC Press (1992), ISBN 978-0-8493-4258-5.〕 The Ural owl has an extended distribution area in Europe and Asia, from Sakhalin, Japan and Korea in the east to Scandinavia in the west. The northern border is at approximately 65 degrees north latitude, and the southern border follows the southern delimitation of the taiga. There are relict populations in the mountains of central Europe belonging to the subspecies ''S. u. macroura''. Birds in northeast Poland and Scandinavia belong to the subspecies ''S. u. liturata'', and those in western Siberia to the nominate race ''S. u. uralensis''. The northern populations of the Ural owl occupy similar habitat to the great grey owl, nesting in lowland forests but avoiding dense areas, especially those of purely conifers. In central Europe it is an upland species, preferring deciduous woodland. It usually occupies open woodland and is more often found in moist rather than dry areas. It nests in hollow tree trunks, occasionally in old raptor nests, and increasingly in nestboxes. It normally lays two to four eggs, which hatch after 27–34 days. The young leave the nest after about four weeks, but will not fly until about six weeks old. It is a very aggressive owl, chasing other birds of prey from its territory, and it will attack human intruders, especially when young are present. The Ural owl feeds on rodents and medium-sized to large birds such as jays and willow ptarmigan, although normally only up to the size of a woodpigeon. Its territorial call, which can carry up to two kilometres, is a soft, deep ''wo-ho….. woho uhwo-ho''. Birds also give unmistakable yapping ''bau - wau'' calls, which are delivered by both sexes. Strix uralensis Zoo Praha 2011-1.jpg|Ural owl in Prague Zoo. Händkakk 2014.JPG|A young Ural owl who has just left the nest. Albu Parish, Estonia. ==References== 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「ural owl」の詳細全文を読む スポンサード リンク
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