A mysterious gooey substance floating in the Bay Area's waters is killing scores of sea birds and has left state wildlife officials searching for answers.
Since Friday, the substance has floated in the Northern California waters from Fremont to Alameda Island next to Oakland and killed 100 birds and coated at least 300 more, said Andrew Hughan, a spokesman for the California Department of Fish and Wildlife.
After testing, officials determined the substance was not toxic, poisonous or harmful to humans.
Volunteers with International Bird Rescue have been combing the 18-mile stretch of coastline to rescue surviving birds and to pick up bodies before scavengers flock to the area, Hughan said. They don't expect to find any more survivors.
The substance has a gray appearance with black dots and feels like rubber cement. Hughan said lab tests showed the substance wasn't petroleum-based, which may explain why the usual method for cleaning birds after an oil spill – dish soap and water – isn't working in this case.
"It's some material that we nor the wildlife center has ever seen before," Hughan said. "It's a real mystery."
The substance coats the birds feathers and keeps their bodies from insulating until they die of hypothermia, Hughan said. To remove the "goo" as it's being called by rescuers, volunteers coat the birds in a chemical agent and soak them in baking soda and vinegar, then scrub them clean with dish soap and water, said Russ Curtis of International Bird Rescue.
State officials have sent samples of the substance and some of the dead birds to labs in Sacramento for testing. One lab may be able to find genetic signatures in the substance to determine what it is and possibly where it came from; the other will perform necropsies on the birds.
So far, no one has stepped forward to take responsibility for the substance, Hughan said.
"If we can identify them, we're going to go after them," he said.