Highly adaptable, this ubiquitous species may be found in habitats as diverse as coastal marshes, sagebrush, shrub-steppe, and urban supermarket parking lots. The adult male is blackish, showing a purplish sheen on the head and a greenish sheen on his back. Its eyes are yellowish to creamy white. Females and juveniles are dusky brown above and grayish brown below, with paler throat and eyebrows, and brown eyes.
The Brewer's blackbird is a common permanent resident along the coast. West of the Cascades it is common to abundant in inland valleys. Within the Cascades, they are a migrant and summer resident in meadows and at human settlements. East of the Cascades, they are an abundant summer resident and uncommon winter resident. It is found in open areas such as grasslands, pastures, lawns, golf courses, agricultural fields, alpine meadows and beaches and is very common in urban areas.