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For Immediate Release, September 17, 2015

Contact: Jeff Miller, (510) 499-9185, [email protected]

California's Tricolored Blackbirds Move Closer to Federal Protection

SACRAMENTO, Calif.— In response to a petition from the Center for Biological Diversity, the U.S. Fish and Wildlife Service today announced that the tricolored blackbird may qualify for federal Endangered Species Act protection. The Center petitioned to protect tricolored blackbirds under both the federal and California Endangered Species Acts after dramatic declines of nesting colonies due to loss of wetlands and native grasslands, shooting, pesticide use and mass destruction of nests through mowing and harvest of crops the birds use for nesting in California.

“Tricolored blackbirds once formed massive nesting colonies of millions of birds in California’s Central Valley but are now suffering declines comparable to the extinction trajectory of the passenger pigeon,” said the Center’s Jeff Miller. “Endangered Species Act protection is needed to safeguard their vulnerable breeding colonies, especially since the state of California has inexplicably delayed protection for tricoloreds despite warnings by biologists that we could lose this species entirely.”

Comprehensive statewide surveys found only 395,000 tricolored blackbirds in 2008, followed by a decline to 259,000 in 2011 and only 145,000 in 2014 — the smallest population ever recorded.

The Center first petitioned for federal and state protection for tricoloreds in 2004. Both the U.S. Fish and Wildlife Service and the California Fish and Game Commission refused to protect the species. After a decade of further population declines, the Center petitioned again for state protection in 2014. Tricoloreds were protected under the California Endangered Species Act on an emergency basis in December 2014, but those protections expired in June 2015. The Center petitioned a second time for federal listing in February 2015 and a third time for state listing in August 2015.

Today’s “90-day finding” is the first in a series of required decisions on the federal petition. The next step is a full status review of the species by the Fish and Wildlife Service.

Background
The tricolored blackbird (Agelaius tricolor) breeds in dense colonies in California’s Central Valley, coast ranges and Southern California. More than 99 percent of tricoloreds live in California; the primary breeding range is the Sacramento and San Joaquin valleys. Adult males are a glossy blue-black with striking red and white shoulder patches, while females are mostly black with a small reddish shoulder patch. Tricolored blackbirds typically eat insects but will also take grains, snails and small clams.

Tricoloreds form the largest breeding colonies of any North American land bird, with a single colony often consisting of tens of thousands of birds as a defense against predation. In the 1800s one observer described a wintering tricolored flock in Solano County as “numbering so many thousands as to darken the sky for some distance by their masses,” and in the 1930s a biologist reported a flock of more than a million tricoloreds in the Sacramento Valley. Tricolored numbers declined in the Central Valley by at least 50 percent between the 1930s and early 1970s, and an additional loss of more than half the remaining population was reported from 1994 to 2000.

Forced from their natural nesting sites by conversion of wetlands and native grasslands to urban and agricultural development, many tricoloreds have adapted by nesting in agricultural crops — typically dairy silage fields. Harvest of these crops often coincides with egg-laying and hatching, and many tricolor eggs and nests are destroyed during harvests. Recent surveys documented nearly half the entire tricolored population nesting in just two colonies in the Central Valley in dairy silage fields in which thousands of nests containing eggs and hatchlings were mowed down during harvest. An unknown number of tricoloreds are shot each year by rice farmers to protect their crops.

The California Department of Fish and Wildlife and other partners have attempted voluntary measures to save tricolor nests from destruction during crop harvest by making crop purchases or reimbursing farmers for delayed harvest on private agricultural lands where tricolors nest. Unfortunately these efforts have not stopped the decline of the species or prevented destruction of tricolor nests on many dairy farms. For example, in 2011, more than half of all tricolor nests in silage fields were destroyed despite efforts to contact farmers and coordinate buyouts of harvest delays.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 900,000 members and online activists dedicated to the protection of endangered species and wild places.