06/16/2026
June’s Bird of the Month:
The Tricolored Blackbird is one of California’s most unique and threatened native birds. Closely related to the more common Red-winged Blackbird, the male Tricolored Blackbird can be identified by its glossy black plumage and striking red shoulder patches bordered by white. Females are smaller, dark brown, and heavily streaked, helping them blend into nesting habitat.
Unlike most blackbirds, Tricolored Blackbirds are highly colonial nesters, gathering in enormous breeding colonies that can number from hundreds to tens of thousands of birds. Historically, these colonies were among the largest concentrations of land birds in western North America. They nest in dense vegetation such as cattails, tule marshes, Himalayan blackberry thickets, and increasingly, agricultural grain fields. Their nesting season generally runs from March through July. Colonies are highly active and noisy, with males defending small territories while females weave cup-shaped nests attached to emergent vegetation. The birds feed primarily on insects during the breeding season, including grasshoppers, beetles, caterpillars, and other agricultural pests. Outside the breeding season, they also consume seeds and grains.
The Tricolored Blackbird is found almost entirely in California, with the largest populations concentrated in the Central Valley, including portions of the San Joaquin Valley. Smaller populations occur in coastal California, southern Oregon, Nevada, and northern Baja California. Because so much of the species’ global population depends on California habitats, conservation efforts within the state are especially important. The species faces significant environmental and conservation challenges. More than 90 percent of California’s historic wetlands have been lost due to agriculture and urban development, greatly reducing traditional nesting habitat. In recent decades, many colonies have shifted into silage and grain fields, where nests are vulnerable to harvest operations that can destroy entire colonies in a single day. Pesticide use and declining insect populations may also reduce food availability for breeding birds. Today, the Tricolored Blackbird is listed as a threatened species under the California Endangered Species Act. Conservation organizations, farmers, agencies, and volunteers now work together to locate nesting colonies and delay harvests when possible. Community science programs and annual statewide surveys help biologists monitor population trends and identify important breeding sites.
The continued survival of the Tricolored Blackbird depends on protecting wetlands, supporting wildlife-friendly agricultural practices, and maintaining healthy insect populations throughout California’s landscapes. For residents of the San Joaquin Valley, this remarkable bird serves as both a symbol of California’s rich natural heritage and a reminder of the importance of conserving the habitats that sustain wildlife.
