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The Bohemian waxwing (''Bombycilla garrulus'') is a starling-sized passerine bird that breeds in the northern forests of Eurasia and North America. It has mainly buff-grey plumage, black face markings and a pointed crest. Its wings are patterned with white and bright yellow, and some feather tips have the red waxy appearance that give this species its English name. The three subspecies show only minor differences in appearance. Females are similar to males, although young birds are less well-marked and have few or no waxy wingtips. Although the Bohemian waxwing's range overlaps those of the cedar and Japanese waxwings, it is easily distinguished from them by size and plumage differences. The breeding habitat is coniferous forests, usually near water. The pair build a lined cup-shaped nest in a tree or bush, often close to the trunk. The clutch of 3–7 eggs is incubated by the female alone for 13–14 days to hatching. The chicks are altricial and naked, and are fed by both parents, initially mostly with insects, but thereafter mainly fruit. They fledge about 14–16 days after leaving the egg. Many birds desert their nesting range in winter and migrate farther south. In some years, large numbers of Bohemian waxwings irrupt well beyond their normal winter range in search of the fruit that makes up most of their diet. Waxwings can be very tame in winter, entering towns and gardens in search of food, rowan berries being a particular favourite. They can metabolise alcohol produced in fermenting fruit, but can still become intoxicated, sometimes fatally. Other hazards include predation by birds of prey, infestation by parasites and collisions with cars or windows. The Bohemian waxwing's high numbers and very large breeding area mean that it is classified as being of least concern by the International Union for Conservation of Nature. ==Taxonomy== The waxwings are a family, Bombycillidae, of short-tailed stocky birds with soft plumage, a head crest and distinctively patterned wings and tails. There are three species, the Bohemian, cedar, and Japanese waxwings. DNA studies and shared features such as a relatively large size, grey underparts and similar undertail patterns suggest that the Japanese and Bohemian waxwings are most closely related within the genus. Although only the cedar and Bohemian waxwings normally have red tips on their wing feathers, this feature is occasionally shown by the Japanese waxwing, suggesting that this was originally a whole-family characteristic that has been lost in one species, rather than an indicator of a close relationship. DNA analysis confirms that the cedar waxwing diverged early from the other members of the family. Outside the genus, the closest relatives of the waxwings are believed to be the silky-flycatchers, the palmchat, and the grey hypocolius, all of which have sometimes been included in the Bombycillidae.〔 〕 The Bohemian waxwing was described by Linnaeus in his ''Systema naturae'' in 1758 as ''Lanius Garrulus''.〔Linnaeus (1758) (p. 95. )〕 The waxwings were moved to their own genus, ''Bombycilla'', by Vieillot in 1808.〔Vieillot (1808) (p. 88 ).〕 The genus name ''Bombycilla'' comes from the Greek ''bombux'', "silk" and the Modern Latin ''cilla'', "tail";〔Jobling (2010) p. 74.〕 this is a direct translation of the German ''Seidenschwanz'', "silk-tail", and refers to the silky-soft plumage of the bird.〔 The species name ''garrulus'' is the Latin for ''talkative'' and was applied to this bird, as "Garrulus Bohemicus", by Conrad Gessner in 1555;〔Jobling (2010) p. 171.〕〔Gessner (1555) (p. 27. )〕 the term is a reference to a supposed likeness to the Eurasian jay (''Garrulus glandarius'') rather than to the waxwing's vocalisations. The English name "waxwing" refers to the bright red tips of the secondary feathers on its wings, which look like drops of sealing wax, while "Bohemian" follows Gessner's usage, and may refer to the Romani, alluding to the bird's wanderings,〔Holloway (2003) p. 39.〕 or to its presumed origin from Bohemia.〔Cocker & Mabey (2005) pp. 326–327.〕 "Waxwing" and "Bohemian waxwing" were first recorded in 1817, the former as a reference to Vieillot's separation of this bird from the "chatterers". There are three recognised subspecies:〔 〕 *''B. g. garrulus'' (Linnaeus, 1758): the nominate subspecies. Breeds in northern Europe from northern Sweden east to the Ural Mountains. *''B. g. centralasiae'' (Poliakov, 1915): breeds from the Urals eastwards across northern Asia. *''B. g. pallidiceps'' (Reichenow, 1908): breeds in northwestern North America. The differences between these forms are small and clinal, and the species could be possibly considered as monotypic.〔 The fossil record includes Pleistocene deposits from the UK and the Carpathian Mountains.〔〔Főzy & Szente (2013) p. 395.〕 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「bohemian waxwing」の詳細全文を読む スポンサード リンク
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