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The Eurasian sparrowhawk (''Accipiter nisus''), also known as the northern sparrowhawk or simply the sparrowhawk, is a small bird of prey in the family Accipitridae. Adult male Eurasian sparrowhawks have bluish grey upperparts and orange-barred underparts; females and juveniles are brown above with brown barring below. The female is up to 25% larger than the male – one of the largest differences between the sexes in any bird species. Though it is a predator which specialises in catching woodland birds, the Eurasian sparrowhawk can be found in any habitat and often hunts garden birds in towns and cities. Males tend to take smaller birds, including tits, finches, and sparrows; females catch primarily thrushes and starlings, but are capable of killing birds weighing or more. The Eurasian sparrowhawk is found throughout the temperate and subtropical parts of the Old World; while birds from the northern parts of the range migrate south for winter, their southern counterparts remain resident or make dispersive movements. Eurasian sparrowhawks breed in suitable woodland of any type, with the nest, measuring up to across, built using twigs in a tree. Four or five pale blue, brown-spotted eggs are laid; the success of the breeding attempt is dependent on the female maintaining a high weight while the male brings her food. The chicks hatch after 33 days and fledge after 24 to 28 days. The probability of a juvenile surviving its first year is 34%, with 69% of adults surviving from one year to the next. Mortality in young males is greater than that of young females and the typical lifespan is four years. This species is now one of the commonest birds of prey in Europe, although the population crashed after the Second World War. Organochlorine insecticides used to treat seeds before sowing built up in the bird population and the concentrations in Eurasian sparrowhawks were enough to kill some outright and incapacitate others; affected birds laid eggs with fragile shells which broke during incubation. However, its population recovered after the chemicals were banned, and it is now relatively common, classified as being of Least Concern by BirdLife International. The Eurasian sparrowhawk's hunting behaviour has brought it into conflict with humans for hundreds of years, particularly racing pigeon owners and people rearing poultry and gamebirds. It has also been blamed for decreases in passerine populations; scientific research has found no link between increased numbers of Eurasian sparrowhawks and declines in some farmland and woodland birds after World War II. Studies of racing pigeon deaths found that Eurasian sparrowhawks were responsible for less than 1%. Falconers have utilised the Eurasian sparrowhawk since at least the 16th century; although the species has a reputation for being difficult to train, it is also praised for its courage. The species features in Teutonic mythology and is mentioned in works by writers including William Shakespeare, Alfred, Lord Tennyson and Ted Hughes. == Taxonomy == Within the family Accipitridae, the Eurasian sparrowhawk is a member of the large genus ''Accipiter'', which consists of small to medium-sized woodland hawks. Most of the Old World members of the genus are called sparrowhawks or goshawks.〔 The species' name dates back to the Middle English word ''sperhauk'' and Old English ''spearhafoc'', a hawk which hunts sparrows. The Old Norse name for the Eurasian sparrowhawk, ''sparrhaukr'', was thought to have been coined by Vikings who encountered falconry in England.〔 English folk names for the Eurasian sparrowhawk include blue hawk, referring to the adult male's colouration, as well as hedge hawk,〔 spar hawk, spur hawk and stone falcon.〔 The Eurasian sparrowhawk was described by Linnaeus in his 18th century work, ''Systema Naturae'', as ''Falco nisus'',〔 but moved to its present genus by French zoologist Mathurin Jacques Brisson in 1760.〔 The current scientific name is derived from the Latin ''accipiter'', meaning 'hawk' and ''nisus'', the sparrowhawk.〔 According to Greek mythology, Nisus, the king of Megara, was turned into a sparrowhawk after his daughter, Scylla, cut off his purple lock of hair to present to her lover (and Nisus' enemy), Minos.〔 The Eurasian sparrowhawk forms a superspecies with the rufous-chested sparrowhawk of eastern and southern Africa, and possibly the Madagascan sparrowhawk.〔 Geographic variation is clinal, with birds becoming larger and paler in the eastern part of the range compared to the west.〔 Within the species itself, six subspecies are generally recognised:〔〔 * ''A. n. nisus'', the nominate subspecies, was described by Linnaeus in 1758.〔 It breeds from Europe and west Asia to western Siberia and Iran; northern populations winter south to the Mediterranean, north-east Africa, Arabia and Pakistan. * ''A. n. nisosimilis'' was described by Samuel Tickell in 1833.〔 It breeds from central and eastern Siberia east to Kamchatka and Japan, and south to northern China. This subspecies is wholly migratory, wintering from Pakistan and India eastwards through South-East Asia and southern China to Korea and Japan; some even reach Africa. It is very similar to, but slightly larger than, the nominate subspecies.〔 * ''A. n. melaschistos'' was described by Allan Octavian Hume in 1869.〔 It breeds in mountains from Afghanistan through the Himalayas and southern Tibet to western China, and winters in the plains of South Asia. Larger〔 and longer tailed than ''nisosimilis'',〔 it has dark slate-coloured upperparts, and more distinct rufous barring on the underparts.〔 * ''A. n. wolterstorffi'', described by Otto Kleinschmidt in 1900, is resident in Sardinia and Corsica.〔 It is the smallest of all the races,〔 darker on the upperparts and more barred below than the nominate subspecies.〔 * ''A. n. granti'', described by Richard Bowdler Sharpe in 1890,〔 is confined to Madeira and the Canary Islands. It is small and dark.〔 * ''A. n. punicus'', described by Erlanger in 1897,〔 is resident in north-west Africa, north of the Sahara.〔 It is very similar to ''nisus'',〔 being large and pale.〔 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「Eurasian sparrowhawk」の詳細全文を読む スポンサード リンク
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