- 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, North Carolina and northwest Virginia. 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 1000 meters (3300 ft) 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.
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| American Robin |
The American Robin or North 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 flycatcher family. The American Robin is widely distributed throughout North America, wintering south of Canada from Florida to central Mexico and along the Pacific Coast. It is the state bird of Connecticut, Michigan, and Wisconsin. It has seven subspecies, but only T. m. confinis in the southwest 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 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.
This species was first described in 1766 by 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.
This bird breeds throughout most of North America, from Alaska and Canada southward to northern Florida and Mexico. While Robins occasionally overwinter in the northern part of the United States and southern Canada, most migrate to winter south of Canada from Florida and the Gulf Coast to central Mexico, as well as along the Pacific Coast. Most depart south by the end of August and begin to return north in February and March (exact dates vary with latitude and climate). Despite being depicted in the film Mary Poppins "feathering its nest" in London, this species is actually a rare vagrant to western Europe, where the majority of records, more than 20, have been in Britain. In autumn 2003, migration was displaced eastwards leading to massive movements through the eastern US, and presumably this is what led to no fewer than three American Robins being found in Britain, with two attempting to overwinter in 2003–2004, although one was taken by a Sparrowhawk. The most recent sighting in Britain occurred in January 2007.
This species has also occurred as a vagrant to Greenland, Jamaica, Hispaniola, Puerto Rico and Belize. Vagrants to Europe, where identified to subspecies, are nominate T. m. migratorius, but the Greenland birds also included T. m. nigrideus, and some of the southern overshots may have been T. m. achrusterus.
The American Robin's breeding habitat is woodland and more open farmland and urban areas. It breeds only rarely in the southern United States and there prefers large shade trees on lawns. Its winter habitat is similar but includes more open areas.
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