Test results pending in San Francisco Bay mystery goo that killed birds

SAN FRANCISCO — Nearly a week after a mysterious gray gunk surfaced on shorelines in the San Francisco Bay Area, the substance has killed more than 200 seabirds.

As the tally of dead birds has climbed, so has the mystery behind the substance that looks and feels like dirty, rubber cement.

California Department of Fish and Wildlife spokesman Andrew Hughan says laboratory tests and necropsies started earlier this week. Results could come Thursday.

Dead birds — surf scoters, buffleheads and horned grebes — have been found along the shorelines east of San Francisco since last Friday, he said.

The goo covers their feathers, and the birds become unable to insulate themselves. They eventually freeze to death. Hundreds of live birds have been taken to the International Bird Rescue to be cleaned and rehabilitated.