Brewer’s Blackbirds (Euphagus cyanocephalus) are very common in open country of western North America , including human-built habitats such as parking lots, where they can be seen walking on the ground making jerking movements with their heads. Their breeding range expanded eastward in the Great Lakes region during the 20th century. In the winter, Brewer’s Blackbirds spread eastward through the southeastern United States and south to southern Mexico. These blackbirds feed mainly on insects and seeds, with some berries, usually foraging in flocks outside the breeding season. Nesting is often in loose colonies of up to 20 to 30 pairs. (Kaufman 1996; AOU 1998)