Dozens of dead and injured seabirds found coated in black goo are the most visible victims of a 58,000-gallon (220,000-liter) oil spill in the San Francisco Bay that scientists say could threaten wildlife for years.
The spill fouled miles of coastline, sending environmentalists scrambling Thursday to save the bay's birds, fish, invertebrates, and marine mammals.
"The effects of the oil spill could persist for months and possibly years," said Tina Swanson, a fish biologist with the Bay Institute.
Meanwhile questions persisted about why the Coast Guard took so long to report the scope of the spill.
The oil spilled from a South Korea-bound container ship when it struck a tower supporting the San Francisco-Oakland Bay Bridge in dense fog Wednesday.
The accident did not damage the span, but the vessel's hull was gashed, officials said.
Tides carried a plume of heavy fuel beneath the Golden Gate Bridge and into the Pacific Ocean.
By Thursday afternoon, oil had been sighted about 15 miles (24 kilometers) north of the city, and at least eight beaches in San Francisco and Marin County were closed.
Wildlife rescue workers and volunteers combing beaches have found dozens of dead and injured seabirds coated in black oil, said Michael Ziccardi, director of the California Oiled Wildlife Care Network.
Ten to 15 teams were to be dispatched Friday to search for more.