The Brewer's Blackbird (Euphagus cyanocephalus), a medium-sized denizen of the New World blackbird family, is a study in contrasts. The male is cloaked in black plumage, which upon closer inspection reveals an iridescent purple head and neck, with glossy bluish-green highlights adorning the body. His bright yellow eye is a striking feature against the dark feathers. The female, in contrast, is dressed in more subdued tones of brownish-grey, with only a hint of the male's iridescence, and her eye is a dark brown.
Distinguishing the Brewer's Blackbird can be a delightful challenge. The male's shorter bill and iridescent purple head set it apart from the rusty blackbird, its eastern cousin. Unlike the common grackle, the Brewer's Blackbird boasts a shorter tail. Its sharp "check" call is distinctive, aiding birdwatchers in identification.
Brewer's Blackbirds favor open and semi-open areas, often near water, across central and western North America. They adapt well to human presence, commonly found in parking lots and school grounds. Their habitat range is quite broad, from below sea level in Southern California to elevations as high as 8,000 feet, including marshlands and forests.
Permanent residents in the west, some Brewer's Blackbirds migrate to the Southeastern United States and Mexico in spring. Their range has been expanding eastward, particularly in the Great Lakes region, a 20th-century development.
When faced with threats, Brewer's Blackbirds exhibit bold behavior, diving towards predators and emitting alarm calls. On the ground, they are characterized by a distinctive jerking head motion. In colder months, they form flocks, sometimes joined by other blackbird species, while during nesting season, they forage more independently.
The Brewer's Blackbird's vocal repertoire includes a sharp "check" call, which serves as an alarm and a means of communication within the species.
Mating pairs of Brewer's Blackbirds reunite seasonally, with both parents contributing to feeding. Males engage in a display of puffing up feathers and spreading wings and tail to appear larger. Nesting occurs in colonies, with nests built in treetops or among reeds and freshwater plants, depending on proximity to water.
The diet of Brewer's Blackbirds is varied, including seeds, insects, and some berries. They forage in shallow water or fields and are adept at catching insects in flight. In marshy areas, they may wade to catch their prey and have been known to consume small mammals, amphibians, and other birds' nestlings.
The Brewer's Blackbird is protected under the Migratory Bird Treaty Act of 1918. While currently listed as Least Concern, they face moderate threats from climate change, with potential range loss if temperatures continue to rise. Their population has declined by 57% from 1966 to 2019, with an estimated 23 million individuals remaining in the wild.