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The garden warbler (''Sylvia borin'') is a common and widespread small bird that breeds in most of Europe and in western Asia. It is a plain, long-winged and long-tailed typical warbler with brown upperparts and dull white underparts; the sexes are similar and juveniles resemble the adults. Its two subspecies differ only slightly and interbreed where their ranges overlap. Due to its lack of distinguishing features, this species can be confused with a number of other unstreaked warblers. The garden warbler's rich melodic song is similar to that of the blackcap, its closest relative, which competes with it for territory when nesting in the same woodland. The preferred breeding habitat in Eurasia is open woodland with dense low cover for nesting; despite its name, gardens are rarely occupied by this small passerine bird. The clutch of four or five blotched cream or white eggs is laid in a robust cup-shaped nest built near the ground and concealed by dense vegetation. The eggs are incubated for 11–12 days. The chicks are altricial, hatching naked and with closed eyes, and are fed by both parents. They fledge about 10 days after hatching. Only about a quarter of young birds survive their first year. The garden warbler is strongly migratory, wintering in sub-Saharan Africa. A wide range of habitats are used in Africa, but closed forest and treeless Sahel are both shunned. Insects are the main food in the breeding season, although fruit predominates when birds are fattening prior to migration, figs being a particular favourite where available. These warblers have a mixed diet of insects and fruit in their African wintering grounds. The garden warbler is hunted by Eurasian sparrowhawks and domestic cats, and its eggs and nestlings are taken by a variety of mammalian and avian predators. It may be host to various fleas, mites and internal parasites, and it is a host of the common cuckoo, a brood parasite. The large and fairly stable numbers and huge range of the garden warbler mean that it is classed as least concern by the International Union for Conservation of Nature. Despite a small population decline in much of its European range, the bird's breeding distribution is expanding northwards in Scandinavia. == Taxonomy == The genus ''Sylvia'', the typical warblers, forms part of a large family of Old World warblers, the Sylviidae. Fossils from France show that the genus dates back at least 20 million years.〔Mason (1995) p. 11.〕 The garden warbler and its nearest relative, the blackcap, are an ancient species pair which diverged very early from the rest of the genus, between 12 and 16 million years ago. In the course of time, these two species have become sufficiently distinctive that they have been placed in separate subgenera, with the blackcap in subgenus ''Sylvia'' and the garden warbler in ''Epilais''.〔Shirihai ''et al'' (2001) pp. 25–27.〕 These sister species have a breeding range which extends farther northeast than all other ''Sylvia'' species except the lesser whitethroat and common whitethroat. The nearest relatives of the garden warbler outside the sister group are believed to be the African hill babbler and Dohrn's thrush-babbler, both of which should probably be placed in ''Sylvia'' rather than their current genera, ''Pseudoalcippe'' and ''Horizorhinus'' respectively. The garden warbler was first described by Pieter Boddaert in 1783.〔Boddaert (1783) p. 35.〕 The current genus name is from Modern Latin ''silvia'', a woodland nymph, related to ''silva'', a wood.〔Jobling (2010) p. 59.〕 The specific ''borin'' is derived from a local name for the bird in the Genoa area of Italy; it derives from the Latin ''bos'', ox, because the warbler was believed to accompany oxen.〔Jobling (2010) p. 75.〕 There are two recognised subspecies.〔Baker (1997) pp. 339–340.〕 * ''Sylvia borin borin'' (Boddaert, 1783), the nominate subspecies, breeds in western, northern and central Europe to Finland, central Poland, western Hungary and Bosnia. * ''S. b. woodwardi'' (Sharpe, 1877), named for Sharp's collaborator Bernard Barham Woodward,〔Sharpe (1877) pp. 308, 311, plate 14.〕 breeds in eastern Europe and temperate Asia east to western Siberia. Intermediate birds occur where the recognised forms meet and interbreed, and have sometimes been given subspecies status, including ''S. b. kreczmeri'' in Poland and ''S. b. pateffi'' in Bulgaria, but these are not generally accepted as valid taxa.〔 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「Garden warbler」の詳細全文を読む スポンサード リンク
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