On a recent trip to Eagle Lake (Lassen County CA) I noticed several different species of songbirds foraging for insects along the edge of the water. I have no idea what these varied birds were so industriously eating, however, that many songbirds on the shore was unusual.
Brewer’s blackbirds, named after Thomas Mayo Brewer (1814 – 1880), an American ornithologist and naturalist, were among the hungry scavengers. Males are glossy black without markings and have a blue or purple sheen on their head and a greenish iridescence to their bodies, particularly in full sun. The yellow eye of adult males appears to be staring. Female Brewer’s blackbirds (Euphagus cyanocephalus) are plain gray-brown and darkest on the wings and tail with a dark eye. Both Brewer’s blackbird sexes have long black legs and black bills.
Found in open habitats of the North American west, Brewer’s blackbirds inhabit grasslands, meadows, coastal scrub, chaparral, and even woodlands. They adapt well to humans and do well in urban lawns, parks, golf courses and city streets. Most will fly to southern United States or Mexico for the winter, while some fly west to mild coastal areas.
Even though they perch high, Brewer’s blackbirds feed on the ground. As they walk their head jerks with almost every step. These blackbirds mostly eat grain and seeds, although insects are also important in their diet. Occasionally a Brewer’s blackbird will even take a small frog, a young vole or even nestlings of certain other songbirds. Often farmers poison or shoot Brewer’s blackbirds in an attempt to protect their harvests. Indeed these birds do eat crops. Yet Brewer’s blackbirds also destroy large numbers of insects, often picking insects off of livestock, leading some to believe they do more good than harm.
A very social bird, the Brewer’s blackbird will nest in colonies of over a hundred individuals. (Factoid: a group of Brewer’s blackbirds is called a “keg”.) When hawks, owls and other predators threaten their nests, these much smaller birds will dive and strike to fend off the intruder.
In many pictures the male Brewer’s blackbirds seem to be angry. I love their “cross look.”