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The American robin (''Turdus migratorius'') is a migratory songbird of the thrush family. It is named after the European robin because of its reddish-orange breast, though the two species are not closely related, with the European robin belonging to the Old World flycatcher family. The American robin is widely distributed throughout North America, wintering from southern Canada to central Mexico and along the Pacific Coast. It is the state bird of Connecticut, Michigan, and Wisconsin.〔(【引用サイトリンク】author=50 States )〕 According to some sources, the American robin ranks behind only the red-winged blackbird (and just ahead of the introduced European starling and the not-always-naturally occurring house finch) as the most abundant extant land bird in North America.〔McWilliams, Gerald M. & Brauning, Daniel W., ''The Birds of Pennsylvania''. Comstock Publishing Associates (2000), ISBN 0801436435.〕 It has seven subspecies, but only ''T. m. confinis'' of Baja California Sur is particularly distinctive, with pale gray-brown underparts. The American robin is active mostly during the day and assembles in large flocks at night. Its diet consists of invertebrates (such as beetle grubs, earthworms, and caterpillars), fruits, and berries. It is one of the earliest bird species to lay eggs, beginning to breed shortly after returning to its summer range from its winter range. Its nest consists of long coarse grass, twigs, paper, and feathers, and is smeared with mud and often cushioned with grass or other soft materials. It is among the first birds to sing at dawn, and its song consists of several discrete units that are repeated. The adult robin is preyed upon by hawks, cats, and larger snakes, but when feeding in flocks, it can be vigilant and watch other birds for reactions to predators. Brown-headed cowbirds lay eggs in robin nests (see brood parasite), but robins usually reject the cowbird eggs. == Taxonomy == This species was first described in 1766 by Carl Linnaeus in the twelfth edition of his ''Systema Naturae'' as ''Turdus migratorius''.〔 〕 The binomial name derives from two Latin words: ''turdus'', "thrush", and ''migratorius'' from ''migrare'' "to go". The term ''robin'' for this species has been recorded since at least 1703.〔 There are about 65 species of medium to large thrushes in the genus ''Turdus'', characterized by rounded heads, longish pointed wings, and usually melodious songs.〔 A study of the mitochondrial cytochrome b gene indicates that the American robin is not part of the Central/South American clade of ''Turdus'' thrushes; instead it shows genetic similarities to the Kurrichane thrush, ''T. libonyanus'', and the olive thrush, ''T. olivaceus'', both African species. This conflicts with a 2007 DNA study of 60 of 65 ''Turdus'' species which places the American robin's closest relative as the rufous-collared robin (''T. rufitorques'') of Central America. Though having distinct plumage, the two species are similar in vocalization and behavior. Beyond this, it lies in a small group of four species of otherwise Central American distribution, suggesting it recently spread northwards into North America. Seven subspecies of American robin are recognized. These subspecies intergrade and are only weakly defined. * ''T. m. migratorius'', the nominate subspecies, breeds in the US and Canada, other than down the west coast, to the edge of the tundra from Alaska and northern Canada east to New England and then south to Maryland, northwest Virginia, and North Carolina. It winters in southern coastal Alaska, southern Canada, most of the US, Bermuda, the Bahamas and eastern Mexico.〔 * ''T. m. nigrideus'' breeds from coastal northern Quebec to Labrador and Newfoundland and winters from southern Newfoundland south through most of the eastern US states to southern Louisiana, southern Mississippi and northern Georgia. It is uniformly darker or blackish on the head, with a dark gray back. The underparts are slightly more red than those of the nominate subspecies.〔 * ''T. m. achrusterus'' breeds from southern Oklahoma east to Maryland and western Virginia and south to northern Florida and the Gulf states. It winters through much of the southern part of the breeding range. It is smaller than the nominate subspecies. The black feathers of the forehead and crown have pale gray tips. The underparts are paler than those of the nominate subspecies.〔 * ''T. m. caurinus'' breeds in southeast Alaska through coastal British Columbia to Washington and northwest Oregon. It winters from southwest British Columbia south to central and southern California and east to northern Idaho. It is very slightly smaller than the nominate subspecies and very dark-headed. The white on the tips of the outer two tail feathers is restricted.〔 * ''T. m. propinquus'' breeds from southeast British Columbia, southern Alberta, southwest Saskatchewan south to southern California and northern Baja California. It winters throughout much of the southern breeding range and south to Baja California. It is the same size as or slightly larger than nominate ''T. m. migratorius'', but paler and tinged more heavily brownish-gray. It has very little white on the tip of the outermost tail feather. Some birds, probably females, lack almost any red below. Males are usually darker and may show pale or whitish sides to the head.〔 * ''T. m. confinis'' breeds above in the highlands of southern Baja California. This form is particularly distinctive, with pale gray-brown underparts. It is relatively small, and the palest subspecies, with uniform pale gray-brown on the head, face and upperparts. It usually lacks any white spots to the tips of the outer tail feathers, which have white edges. It is sometimes classed as a separate species, the ''San Lucas robin'',〔 but the American Ornithologists' Union regards it as only a subspecies, albeit in a different group from the other races. * ''T. m. phillipsi'' is resident in Mexico south to central Oaxaca. It is slightly smaller than ''propinquus'' but has a larger bill; the male's underparts are less brick-red than the nominate subspecies, and have a rustier tone.〔 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「American robin」の詳細全文を読む スポンサード リンク
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