Everyone has seen Brewer’s Blackbirds. They are in parks, fields, and parking lots. They are the birds that peck bugs from your car bumper. In Birds of Northern California, David Fix writes, “Our immense network of highways has offered the Brewer’s Blackbird a bounty of vehicle-stuck insects. This species exploits the ‘road kill resource’ niche better than any other songbird.”
Brewer’s Blackbirds are 8-10 inches long with a slender, straight bill. The male has a glossy greenish back, iridescent purple head, and bright yellow eyes. The female has brown eyes and a medium-brown body with slightly lighter brown underparts.
Brewer’s Blackbirds live almost everywhere: wet meadows, grasslands, shores, roadsides, landfills, golf courses, urban and suburban parks and gardens, farmyards, pastures and marshes. They nest from sea level to 900 ft.
They peck, glean, and chase food, which includes a variety of spiders, crustaceans, and snails. They may also eat grass and seeds.
During courtship displays and when they are threatened, Brewer’s Blackbirds call and lift their beaks, fluff their feathers, and spread their wings and tails. A pair may remain together for five years, but some males are polygamous. They nest in loose colonies of three to 100 pairs. The nest is constructed of twigs, cow dung (or mud), grass (or fur), and lined with fine material. Females incubate 4-6 greenish eggs with brown and gray spots. In non-breeding season, Brewer’s Blackbirds join other birds like Red-winged Blackbirds, Brown-headed Cowbirds, and European Starlings. They may form huge, cacophonous flocks.