The Brewer's blackbird (Euphagus cyanocephalus) is a medium-sized New World blackbird. It is named after the ornithologist Thomas Mayo Brewer. Adults range in length from 8.3 to 9.8 inches. Adult males have black plumage with an iridescent purple head and neck and glossy bluish-green highlights on the rest of the body. The feet and legs are black and the eye is bright yellow. The female is brownish-grey with slight hints of the male's iridescence. The female's eye is dark brown. This bird is often mistaken for the common grackle but has a shorter tail. Brewer's blackbirds are year-round residents of the COSA.