| The male Rose-breasted Grosbeak should not present any problem in identification. The breast and lining of wings are a bright rose color while rest of underparts and the rump are white. The head, chin, and back are black as are the wings and tail which also have white markings. The bill is grayish white. But the female, entirely different in plumage markings, suggests an overgrown sparrow or finch. The size and shape of her bill, however, will indicate her identity as a grosbeak. By elimination, her species can then be determined, for her plumage bears little resemblance to that of Pine or Evening Grosbeak females. The female is brown above with buff edged feathers. The wings and tail are brown with white markings while the lining of wings yellowish brown. There is a white line over eye and buff-colored line through the center of crown. The bill yellowish white.
The song of the Rose-breasted Grosbeak can be mistaken it for that of a robin but the cautious listener will detect a slight difference. The grosbeak notes are more hurried than those of the robin. It is thought that male birds are brightly colored because their plumage will attract the eyes of predators and help hide the true location of the nest. However the male Rose-breasted Grosbeak will build the nest while the female brings the material and sing constantly. The male will also sing when it takes its turn incubating the eggs. Even the sparrow-colored female tosses aside her natural camouflage by singing while building the nest. This may explain why there nests are commonly parasitized by the brown-headed cowbird.
The male will also sing in flight while pursuing the female during the courtship. The male crouches, spreads and droops the wings with the tail spread and slightly elevated, and retracts the head while waving the head and body in an erratic dance. The male will usually pick the nest site and build the fragile nest which seems too flimsy to serve its intended purpose and is usually composed wholly of twigs, lined with more delicate twigs and fine rootlets. The usual location is the upright crotch of a small deciduous tree or bush, often in hedgerows along the open countryside. It is placed at low heights, usually within 20 feet of the ground. Because of the thick foliage, the nests are difficult to find in summer but are quite conspicuous after the leaves have fallen and are readily distinguished by their general appearance of fragility. The frequency with which old nests are found next to new nests suggests that the bird is accustomed to returning to the same immediate area for nesting year after year.
A clutch consists of 3-5 light blue eggs, marked irregularly with spots of brown of various shades and densities. The eggs are incubated for about 13 days by both male and female and leave the nest in 9-12 days. If a second brood is started the female will build the second nest while the male incubates the first. The diet consists of fruit seeds and insects which it gleans by hovering but sometimes gleaned from the ground.
The breeding habitat consists of open brushy deciduous woods and aspen groves from northern and central Canada south to eastern Kansas, central New Jersey, and the mountains of Georgia where they arrive in April or May. They winter in southern Mexico to Venezuela and Ecuador, but occasionally will frequent feeders in the northern United States. Migratory peaks occur from late August to late September, but stragglers are frequent sometimes as late as November.
Length 7 - 8 1/2 inches
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