Tricolored Blackbird Moves Toward Endangered Species Designation

Tricolored Blackbirds breed in large colonies, sometimes with 20,000 birds all crammed together, maybe a foot or two between each nest. Those large colonies are getting harder to find, as the bird population plummets.

Last December, the Center for Biological Diversity petitioned California Department of Fish and Wildlife to consider listing the Tricolored Blackbird as an endangered species. That process requires feedback from the public about the bird’s distribution, abundance and biology.

Neil Clipperton, a biologist with the California Department of Fish and Wildlife, says his agency is soliciting information from the public to learn as much as they can about this species. He says they know a lot already and are hoping to learn more.

“Although it’s a blackbird and I think it’s under-respected for that reason, it’s one of the most unique songbirds in North America. Behaviorally it’s the only colonial nesting songbird left in North America,” says Clipperton. “Their socialness and they way they interact in their breeding and the immense density that they nest at is a spectacle you don’t see with any other species.”

At the end of the 19th century the Tricolored Blackbird was described as the most abundant bird species in California. Spanish Explorers thought the sky was filled with smoke from fires, but it was just the birds coming off the wetlands. In 2011 an estimated 258,000 birds lived in California. In 2014 that number slumped to just 145,000 birds, a decline of 44 percent.

"Back in the '30s there were millions of the bird," says Michael Lynes, the director of public policy at the California Audubon Society. "It's really declined very significantly from its historic numbers in California, primarily due to the loss of wetland habitat. We've lost 90 to 95 percent of our wetland habitat, which is what this bird relies on."

Lynes says birds that nest in large colonies like the Tricolored Blackbird risk rapid extinction when their population numbers drop.

"Colonial nesters need to have fairly large numbers in order to maintain a sustainable population over time," explains Lynes. "Our concern is this population is going to crash in the way the Passenger Pigeon, the Carolina Parakeet did—their numbers just dropped off a cliff and then the bird was extinct."

Tricolored Blackbirds tend to nest in farm land in the San Joaquin Valley, in the grains dairy farmers grow to feed their cattle.

Paul Sousa with the Western United Dairymen says his organization has worked to protect the bird for more than ten years, with the goal of keeping the bird off of the endangered species list.

“The hope was to protect the bird and keep its numbers up. We want to see the bird thrive, but we want maximum flexibility on our private lands to do our normal farming practices," says Sousa. "That may be possible, if the bird has a population large enough that it’s not in danger of going extinct.” 

In 2014 the federal government paid farmers $370,000 to delay harvesting until after the breeding season. In January The USDA's Natural Resources Conservation Service gave $1.1 million to Audubon California and dairy farmers to help save the bird.

Lynes says paying farmers to defer their harvests helps, but it's not a long-term solution.

"Over time the goal would be to create new habitat outside of farms that these birds would use, so they could be sustainable in the long term," Lynes says.

This month, colonies of Tricolored Blackbirds will settle down to nest in eight to 10 Central Valley farmer’s grain crops. Lynes says the problem is localized.

In the past, farmers have mowed down crops in the middle of the breeding season. If the Tricolored Blackbird is added to the endangered species list this would be expressly illegal.  

Comments and data can be sent to wildlifemgt@wildlife.ca.gov.