American Robin

Description

The eastern subspecies (T. m. migratorius) is 23 to 28 cm (9.1 to 11.0 in) long with a wingspan ranging from 31 to 41 cm (12 to 16 in), with similar size ranges across all subspecies. The species averages about 77 g (2.7 oz) in weight, with males ranging from 72 to 94 g (2.5 to 3.3 oz) and females ranging from 59 to 91 g (2.1 to 3.2 oz). Among standard measurements, the wing chord is 11.5 to 14.5 cm (4.5 to 5.7 in), the culmen is 1.8 to 2.2 cm (0.71 to 0.87 in) and the tarsus is 2.9 to 3.3 cm (1.1 to 1.3 in). The head varies from jet black to gray, with white eye arcs and white supercilia. The throat is white with black streaks, and the belly and undertail coverts are white. The adult has a brown back and a reddish-orange breast, varying from a rich red maroon to peachy orange. The bill is mainly yellow with a variably dark tip, the dusky area becoming more extensive in winter, and the legs and feet are brown. The sexes are similar, but females tend to be duller in color than males, with a brown tint to the head, brown upperparts, and less-bright underparts. However, some birds cannot be accurately sexed on the sole basis of plumage. Juveniles are paler in color than adult males and have dark spots on their breasts and whitish wing coverts. First-year birds are not easily distinguishable from adults, but they tend to be duller, with first-year males resembling adult females, and a small percentage retain a few juvenile wing coverts or other feathers.

Range & habitat

The species 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). The distance by which they migrate varies significantly depending on their initial habitat; a study found that individual robins tagged in Alaska are known to travel as much as 3.5 times farther across seasons than robins tagged in Massachusetts. The species is a rare vagrant to western Europe, where the majority of records have been in Great Britain, where 30 had been recorded up to the end of 2024. The species has occurred as a vagrant to Greenland, Sweden, Jamaica, Hispaniola, Puerto Rico and Belize. Vagrants to Europe, where identified to subspecies, are the eastern subspecies (T. m. migratorius), but the Greenland birds included the Newfoundland subspecies (T. m. nigrideus), and some of the southern overshots may have been the southern subspecies (T. m. achrusterus). The breeding habitat is woodland and more open farmland and urban areas. It becomes less common as a breeder in the southernmost part of the Deep South of the United States and there prefers large shade trees on lawns. Its winter habitat is similar but includes more open areas.

Behaviour

The American robin is active mostly during the day, and on its winter grounds, it assembles in large flocks at night to roost in trees in secluded swamps or dense vegetation. The flocks break up during the day when the birds feed on fruits and berries in smaller groups. During the summer, males defend a breeding territory and are less social.

Adapted from American robin on Wikipedia, used under CC BY-SA 4.0.