Parasite killing large numbers of birds on Central Coast

Feb 3, 2015

A band-tailed pigeon is studied by workers with the California Department of Fish and Wildlife back in 2011.
Credit CDFW

A migratory bird that uses the Santa Ynez Valley as its winter feeding home is dying off by the hundreds because of a deadly parasite—avian trichomoniasis.

The band-tailed pigeon is native to the West Coast, but is somewhat unfamiliar to people because it doesn't live close to the ground and prefers rural settings. Dry winters force it to find alternate water sources, often closer to urban areas.

Krysta Rogers investigates these types of mortality events for the California Department of Fish and Wildlife and says her research currently points to the drought as a possible factor.

"It does seem that these mortality events are more likely to occur when we have drier winters," said Rogers. "Obviously when there is less precipitation, there's less natural water sources for the birds to use, so if we do have a sick bird then the disease can spread that much more easily when they're in that closer contact."

Rogers says the birds are typically on the Central Coast through April and then return to their homes farther north in California, Oregon, and Washington.

Large numbers of dead band-tailed pigeons have also been found recently in the Los Gatos and Saratoga areas of Santa Clara County.