The male is completely black except for a red shoulder patch (epaulet) with a narrow, yellow horizontal bar at the base of the patch. The female is brown above and has vertical brown and buff streaks below. The Red-winged Blackbird is a medium-sized songbird, about 22 cm long (8.5 in).
Breeding season lasts from February through August. The birds commonly nest in marsh or prairie habitat. The female builds a cup-shaped nest about 1-2 m (3-6 ft) above ground or water. She weaves the nesting material, usually grasses or reeds, into several upright cattails, reeds, or grasses for support. The female lays 3 - 4 greenish-blue eggs with brown spots, which she incubates for 11 days. Young are altricial. Both parents feed insects and insect larvae to the nestlings for 14 days. Then the young fledge from the nest. Red-winged Blackbirds are often polygamous.
The Red-winged Blackbird inhabits both wetland areas, such as freshwater and saltwater marshes, and dry upland areas, such as meadow, prairies, and old fields. During the breeding season, it forages primarily on insects and other invertebrates. During the winter months it feeds primarily on grains. Large foraging flocks are common during winter and, less commonly, during the summer away from the breeding territories. Large migratory flocks may be observed during fall and early spring. Predation of eggs and nestlings is common. Nest predators include birds, snakes, and the Raccoon.
The Red-winged Blackbird occurs year-round throughout Georgia where suitable habitat is present. The species also ranges throughout the United States.
These birds are common in appropriate habitats.
Other black birds, such as the Grackle and the Blackbird, lack the male's the red shoulder patch. Other brown birds, such as female Grackles and female Blackbirds, do not have the conspicuous streaking on the breast and underside found on the female Red-winged Blackbird.