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This stocky, medium-sized songbird is 7-8.5 inches long, has a wingspan of 11-13 inches, and weighs 1.4-1.7 ounces. It is broad-chested, with a short neck and a medium-length, squared tail.
Adult males are black above and white below, with a brilliant red chevron extending from the black throat down the middle of the breast, white patches on the upper sides of the wings and red markings on the undersides that are clearly visible in flight. The red breast becomes duller when the male is not in its breeding plumage. Adult females are brown above, with white wing patches, streaked brown breast, and pale eyebrow. Both sexes have a heavy, short, pinkish bill, dark brown eyes, and grey-blue to black legs. Juveniles look like adult females, but the wings and tail are usually browner, the breast is buff, and it is less heavily streaked overall.
Distribution and Habitat
The rose-breasted grosbeak breeds from western Canada south through the United States east of the Continental Divide, and winters from central Mexico south through Central America into northern South America, as well as many Caribbean islands.
Throughout its range, this bird is found in both deciduous trees and conifers. It is most common in regenerating woodlands and often concentrates along forest edges and in parks. During migration, rose-breasted grosbeaks frequent fruiting trees to help fuel their flights. It usually begins its northward migration between mid-March and mid-April, and starts south in mid-September, with most flight taking place at night.
At the beginning of the breeding season, the female rose-breasted grosbeak approaches a singing male, who in turn performs a courtship display involving flight, positioning and song. Once formed the pair is monogamous.
Nest-building usually takes place between May and June, with both sexes taking part in the process. The site is usually in a vertical fork or crotch of a sapling 5-50 feet above the ground, usually in forest openings, overgrown field edges, old pastures, shrubby roads, railroad rights-of-way, gardens, parks, or residential areas. The nest itself is a flimsy saucer of twigs, stems, and grass that measures 3.5-9 inches across and 1.5-5 inches high on the outside (3-6 inches across and 1-3.5 inches deep on the inside). Red-breasted grosbeak nests are often so flimsy that the eggs can be seen through the bottom.
Three to five pale blue or green eggs spotted with brown splotches (each about 1 inch long) are laid between mid-May and July and incubated by both parents for 9-13 days. The young are fed insect matter by both adults and may fledge the nest just 9 days after hatching, although fledging at around 10 days is more common. The young are dependent on the adults for around 3 weeks after fledging, with family groups being maintained until migration occurs at the end of the summer.
During the breeding season rose-breasted grosbeaks eat a lot of insects, as well as wild fruit and seeds. They mostly feed on berries during fall migration, and on their wintering grounds they have a varied diet of invertebrates and plant material. They are also frequent visitors to backyard bird feeders, where they eat sunflower seeds with abandon.
Males sing to establish territories and attract females, as well as during nest-building and incubation. Their distinctive call note is a sharp, penetrating, metallic eek-eek that is similar to that of an American robin, but softer and more melodious.
During the breeding season, the male and female rose-breasted grosbeak are intolerant of other individuals and are often involved in conflicts when defending their territory. During winter and migration, however, this species is relatively gregarious, forming flocks of up to 50 birds
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This page was last updated on March 22, 2018.