Bird Lore: Brewer’s Blackbird

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The Brewer’s Blackbird is common in towns as well as open habitat throughout the North American West. In rural areas it is usually found in large mixed flocks of blackbird species and starlings, frequently around dairy farms. In cities and towns, it can be found foraging on the ground in grocery store or drive-in parking lots and on sidewalks. Parks and golf courses are other sites that attract this blackbird. In Western Washington it is a year-round resident.

Perhaps the parking lots of our drive-ins and supermarkets are a bit too clean in Edmonds because the Brewer’s Blackbird is notable for infrequent sightings. For several years, a pair of them have been denizens of Olympic Beach, the Senior Center grounds, the public pier and the Edmonds Marsh. In the last year, the female has not been seen with the male. Did he move on? Did he become food for a hawk or eagle? Maybe she’ll find a new companion.

The male is striking because of his bright eye that mostly appears yellow. He lacks the red and yellow chevron of the Red-winged Blackbird, but makes up for it with his glossy black plumage highlighted with midnight blue and metallic green. His female counterpart sports a dark eye and drab brown plumage. In good light you can see hints of light blue iridescence on her wings and rump.

The Brewer’s Blackbird mostly eats insects and seeds. Insects include termites, caterpillars, aphids, beetles, grasshoppers and crickets, and some spiders, snails and small crustaceans. It eats a variety of grass and weed seeds as well as waste grain. Unfortunately, in some agricultural areas the species is trapped, poisoned or shot because of an inaccurate assumption that it is a pest. Its appetite for insects makes it more of a friend than a foe to farmers.

Nesting colonies of 20-50 pairs are common. In courtship displays, the male points his bill up or forward, fluffs his body feathers, and partly spreads his wings and tail. The nest site is variable. It can be 20-40 feet up in a trees, it may be in tall grasses on the ground, in a bush, or in a cliff crevice. The female builds the nest, which is a bulky, open cup of twigs, pine needles, grasses and weeds. Mud or dried manure is often added to the base of the nest. It is then lined with fine grass and animal hair.

The female incubates her four to six eggs for about two weeks. Both parents feed the nestlings and the young leave the nest at about two weeks of age. The Brewer’s Blackbird has one or two broods per year.

The oldest known Brewer’s Blackbird was a male that was at least 12 years and six months of age when it was found in California. There are a number of collective nouns for all blackbird species, including cloud, flock, grind and merl.

Although the Brewer’s Blackbird is common within its range, its population declined by 69 percent between 1966 and 2014. It is characterized as a common bird in steep decline. Nonetheless, the organization Partners in Flight estimates its breeding population at 20 million, with 74 percent spending part of the year in the U.S., 26 percent in Canada, and 25 percent wintering in Mexico.

The Brewer’s Blackbird has a rather simple song that can be heard here: http://www.xeno-canto.org/352025. Its call can be heard here: http://www.xeno-canto.org/186654.

— By Carol Riddell

Carol Riddell manages the bird education displays, on behalf of Pilchuck Audubon Society and Edmonds Parks & Recreation, at the Olympic Beach Visitor Station.

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