Fuel spilled from the Cosco Busan more than two weeks ago continued its carnage of San Francisco Bay wildlife over the Thanksgiving weekend, with 173 local and migratory birds killed or found killed, taking the grim death toll Sunday to 2,125 birds and a harbor seal.
Hundreds of trained volunteers and workers have collected and rescued birds affected by oil after the Cosco Busan scraped against a Bay Bridge tower Nov. 7, which led to a 58,000-gallon spill of low-grade shipping fuel.
Of the 2,647 birds collected as of Sunday, 2,125 were dead and 188 had been released, according to official figures. Another 334 were being cleaned and rehabilitated by hopeful rescue workers, although many of those will also die.
Birds can freeze to death when they’re covered with oil because their feathers lose insulating properties, and they can die after they eat or ingest the toxic sludge.
Birds of threatened and endangered species have been killed, said Sylvia Wright of the Oiled Wildlife Care Network at UC Davis, including three marbled murrelets, two brown pelicans anda snowy plover.
Just 2,300 tiny snowy plovers live and breed on West Coast beaches, according to the Center for Biological Diversity.
Figures provided by Wright paint a gloomy picture around the Bay, which is a popular stop for birds as they migrate along the Pacific Flyway between Alaska and Chile.
According to Wright’s figures, birds from 57 species have been found dead by the end of last week, including more than 300 surf scoters. Eighty thousand of the 18-inch black and brown ducks call the Bay home during winter, according to researchers at the U.S. Geological Survey.
More than 200 Western grebes have also been killed, according to Wright. The ducks, which have pointy beaks and swanlike necks, are found from Mexico to Canada, and they nest in plants on the Bay during spring and summer.
Scoters and grebes are “especially susceptible” to the fuel, Golden Gate Audubon Society Executive Director Elizabeth Murdock said, because “they spend a lot of time in the Bay — they dive to the bottom of the Bay to feed on crustaceans.”
Birds and other wildlife will continue to be harmed by the fuel long after cleanup crews have gone home, Murdock warned, as toxins from the fuel build up in their prey.
“Having a crisis like the oil spill just puts additional stress on these birds,” she said. “They both have suffered population declines over the last few decades.”
Species most frequently killed by the spill
» Surf scoters
» Western grebes
» Common murres
» Western grebes and Clark’s grebes
» Brandt’s cormorants
» Greater scaups
» Eared grebes
Source: Oiled Wildlife Care Network