Rusty Blackbird

Adults have a pointed bill and a pale yellow eye. They have black plumage with faint green and purple gloss; the female is greyer. "Rusty" refers to the brownish winter plumage. They resemble the western member of the same genus, the Brewer's blackbird; however, Brewer's has a longer bill and the male's head is iridescent green.

Their breeding habitat is wet temperate coniferous forests and muskeg across Canada, New England, the Upper Peninsula of Michigan, the Adirondack Mountains in New York and Alaska. Birds usually nest at the edge of ponds and wetlands with the cup nest located in a tree or dense shrub, often over the water. Emerging dragonflies and their larvae are important food items during the summer. These birds migrate to the eastern and southeastern United States, into parts of the Grain Belt, sometimes straying into Mexico. Additional vagrants have been reported inn Greenland and Russian Siberia.

Rusty blackbirds forage on wet ground or in shallow water, mainly eating insects, crustaceans, small fish during the breeding season. In winter, their diet is more flexible, and contains grains (e.g., corn and rice) and other seeds. In fragmented landscapes, overwintering populations may also rely on the mast of seed-producing trees, such as pecans and oaks. They very rarely will attack small passerine birds in periods of extreme food shortage. They feed in flocks during migration and on the wintering grounds, both in conspecific and mixed-flocks alongside red-winged blackbirds, common grackles, and European starlings. They more often roost with other blackbirds; some small roosts are in brushy vegetation in old fields and others are in massive mixed flocks—sometimes in the urban areas. The species nests relatively early for a boreal forest bird. They linger in the boreal zone to complete their molt. Their autumn migration is slow, with birds often remaining in the northern states well into December; spring migration is much more rapid. The largest wintering concentrations are found in the lower Mississippi Valley, with smaller concentrations in the Piedmont and south Atlantic coastal plain. Fairly quiet in fall migration and most of the winter, both males and females will sing (particularly on warm days) in the late winter and spring. …