Agelaius

Agelaius is a small genus of passerine birds in the family Icteridae, commonly known as blackbirds. The genus includes three species: the red-winged blackbird (Agelaius phoeniceus), the tricolored blackbird (Agelaius tricolor), and the yellow-shouldered blackbird (Agelaius flavus).

Members of Agelaius are medium-sized, predominantly dark birds; males typically possess conspicuous shoulder patches or other display features, while females are smaller and more cryptically colored. They are found in the Americas, from southern Canada through much of the United States and into Central America and the Caribbean. They occupy wetlands, marshes, open fields, and agricultural margins, and are often seen in and around dense vegetation used for nesting.

Behaviorally, Agelaius species are highly social, frequently forming large foraging flocks and nesting colonies. They are vocal birds, with songs and calls that play a role in territory defense and mate attraction. Their diet includes seeds, grains, and insects, with foraging shifting to whatever is seasonally available.

Breeding involves colonial or semi-colonial nesting, typically in dense marsh vegetation or tall grasses. The female lays a clutch of eggs, and both parents participate in incubation and feeding of the young. While the red-winged blackbird is widespread and common, the other two species have faced habitat-related declines in parts of their ranges and are of conservation concern in some regions.

Overall, Agelaius reflects a group of adaptable, social, and vocally active blackbirds with a strong association to wetland and edge habitats.