Fewer burrowing owls are returning to the Berkeley area as their population continues to dwindle, not only in California but across North America.
Burrowing owls are small birds that live in burrows created by other animals. As a result of habitat loss in recent years, the California population of burrowing owls has declined, according to Scott Artis, the executive director of the Urban Bird Foundation.
“We’re going to wake up one day and see that we don’t have burrowing owls anymore,” he said. “(The cause is) really this loss of habitat. … That can mean the physical loss of land itself or … invasive weed species that can infiltrate grasslands.”
Artis said that migratory burrowing owls return to the same spot every year. But these areas may be developed, so it is not uncommon to see the birds standing around a site uninhabitable to them — until the owls disappear from the area altogether.
One such development that has displaced burrowing owls is the Tom Bates Regional Sports Complex, according to Della Dash, a volunteer for the Golden Gate Audubon Society, or GGAS, docent program. In order to minimize the environmental impact of the complex’s development, a mitigation site was created in Albany to set aside a different place for the owls to inhabit, Dash said. It is only now — eight years later — that an owl has been spotted using the site.
The gradual loss of a suitable habitat has contributed to a 28 percent decrease in the burrowing owl population across the San Francisco Bay-Delta region since 1993, in addition to the 50 percent decrease that occurred in the area from the 1980s to 1993, Artis said.
Despite these declines, burrowing owls are listed only as a species of special concern in California, rather than as endangered or threatened.
“The Western burrow owl is endangered in Canada, it’s threatened in Mexico,” Artis said. “(A species of special concern) is a pre-threatened designation. … It’s that step before they would be upgraded to threatened.”
The change from special concern to endangered would come with a comprehensive conservation agenda, according to Artis, which would expand protection efforts statewide in California.
Locally, GGAS works in collaboration with the city of Berkeley; the East Bay Regional Park District, or EBRPD; and other city governments to train docents to educate the public about burrowing owls. The docents, for example, warn the public of the danger that pets may pose to burrowing owls, especially unleashed pets that may frighten or even kill the owls.
“We worked closely with the city for many years. The city has been nothing but supportive,” Dash said. “The docent (program) has been so successful that it has resulted in the decrease of off-leash dog walkers.”
Despite the GGA’s efforts, the number of owls spotted along the Berkeley Shoreline — an area that includes the Tom Bates Regional Sports Complex, Cesar Chavez Park and the McLaughlin Eastshore State Park — has dropped from six in 2012 to two in 2015.
EBRPD has purchased land to improve environmental protection, which should help provide the burrowing owls with a new home, according to Steven Bobzien, EBPRD ecological services coordinator.