To save the Tricolored Blackbird, one conservation group is pulling out all the stops. A petition filed Tuesday with the U.S. Fish and Wildlife Service by the Center for Biological Diversity seeks Endangered Species Act protection for the rapidly disappearing passerine.
For decades, agricultural intensification and severe drought in California, where more than 99 percent of the all Tricoloreds live, has chipped away at the bird’s Central Valley wetland habitat. Pesticides that kill off their prey and farmers who shoot individuals they find in their crops have only accelerated the crash: In 2008, the bird numbered 395,000 individuals. By 2014, the species’ population had plummeted to less than half that.
The nosedive is especially problematic because the Tricolored’s breeding success partly depends on keeping its nesting colonies large enough. Once their numbers dip below a certain point, runaway breeding failures could decimate the species, says Jeff Miller, a conservation advocate at the Center for Biological Diversity. “The real question is: What’s the threshold below which the population can’t recover?” Miller says. “Hopefully we haven’t reached that.”
The petition is the latest escalation in the effort to rescue the bird. The Tricolored has already been granted a temporary, six-month “endangered” status in Calfornia. It was the first ever emergency listing under the state’s Endangered Species Act (California Fish and Wildlife will decide whether to make it permanent when the term lapses).
But federal protections are needed as well, Miller argued. “The state law protects the bird, but not the habitat,” Miller says. “A federal listing could lead to critical habitat designation and a recovery plan.”
Similar in appearance to the much more common Red-winged Blackbird, which also lives in California, the Tri-colored Blackbird forms the largest breeding colonies of any extant North American land bird. Some of these colonies consisted of hundreds of thousands of individual birds, forming hordes similar to the clouds of Passenger Pigeons that once blackened the skies before the pigeon went extinct over a century ago. [[link to passenger pigeon feature]]
“It’s a species that almost literally puts all its eggs in one basket,” Miller said. “It’s a good strategy for dealing with predators, but unfortunately it does make it vulnerable to human impacts.”
Meghan Hertel, working lands director at Audubon California, said her organization backed the state listing and will likely support a federal designation as well.
“But it’s just one tool in a toolkit,” she said. “A lot of work has to be done on the ground in partnership with the people who have these birds on their property.”
Audubon has, for example, worked with dairy farmers to delay the harvest of triticale [[link]]—a rye-wheat hybrid that’s fed to cows—until Tricolored Blackbird young can fledge. It also wants to protect and restore the species’ original wetlands habitat.
Till then, Hertel underlines just how hard the Tricolored’s disappearance hits home for people in the Golden State. “It’s a pretty phenomenal and unique species,” she says, “but now very few people in California have seen or even heard of a Tricolored Blackbird, which is pretty disheartening.”