A vanishing songbird that was once the most common bird in California is being formally considered for protection under the state's Endangered Species Act. On Friday, the state's Fish and Game Commission agreed to make the tricolored blackbird a candidate for listing under CalESA, reversing a controversial decision made in June to let protections lapse.
The tricolored blackbird (Agelaius tricolor), which once numbered in the uncountable millions in California, has dwindled to the point of near-extinction as a result of damage to its wetland and grassland habitat throughout the state. Though individual flocks may still number in the tens of thousands, that seeming abundance actually makes the tricolored vulnerable: by gathering in massive breeding colonies on the agricultural lands that have replaced its native habitat, the bird can lose huge chunks of its population to a single ill-timed pass of a tractor.
"There's no question that tricolored blackbirds desperately need this long-overdue protection to avoid their slide toward extinction," said Ileene Anderson, a senior scientist with the Center for Biological Diversity, which had petitioned the Fish and Game Commission to list the bird. "The California Fish and Game Commission made the right decision, based on the overwhelming science documenting the ongoing population declines of these birds."
"The Fish and Game Commission made the right decision," said Brigid McCormack, executive director of Audubon California on Friday. "We are pleased that this consideration triggers protections for this struggling species."
Though flocks of a million tricolored blackbirds were a common sight as recently as the 1930s, destruction of their wetland and native grassland habitat caused a 50 percent drop in population by the 1970s. In 2008, surveys found just 395,000 of the birds in California, and that figure was down to 145,000 by 2014.
A significant problem is that tricoloreds establish their nesting colonies in fields of grain such as triticale, which mimic the grassland habitat in which the birds evolved. Triticale is grown as livestock feed by the Central Valley's dairy farmers, and peak harvest time often coincides with the weeks when tens of thousands of tricolored blackbirds may be in the fields, raising their young.
Dairy farmers are often willing to delay their harvests to allow the birds to leave, and conservation groups and state agencies have sometimes lent those farmers a hand to buy replacement grain for their livestock. But that nascent cooperation, as promising as it is, hasn't been enough to stem population losses.
Listing under the California Endangered Species Act would mean that farmers whose fields are occupied by tricolored blackbirds couldn't legally harvest their grain -- thus destroying the birds' nests -- without an incidental take permit, and getting one of those permits would likely take longer than just waiting for the birds to leave.
The Center for Biological Diversity first petitioned the Fish and Game Commission to list the bird in 2004. Rebuffed, the group petitioned again in 2014; that petition failed this summer. The group re-submitted the petition with two new studies on tricolored population declines in August, and Friday's 3-1 Fish and Game Commission vote on the new petition temporarily gives the tricolored all the protection of formal listing.
Friday's vote by the Fish and Game Commission starts the clock on a 12-month review process during which the California Department of Fish and Wildlife assess the merits of listing the species. Staff of that agency have already suggested that listing may be strongly advisable.
The Center has also petitioned the U.S. Fish and Wildlife Service to list the bird under the Federal Endangered Species Act; that petition was accepted by USFWS earlier this year, and that agency is considering whether to place the bird on the federal list of Endangered Species. The tricolored is already protected under the federal Migratory Bird Treaty Act.