Study: Cosco Busan oil spill damaged herring


Scientists from UC Davis, along with national researchers, say even small oil spills can have a devastating impact on marine life. Their findings are published in the journal Proceedings of the National Academy of Sciences.

It was November 2007 when the container ship Cosco Busan struck the base of one of the towers of the Bay Bridge. More than 50,000 gallons of bunker oil leaked into the bay. Scientists and environmentalists knew the accident would have a huge impact on marine life, but new research shows for the pacific herring population, it was a disaster..

"We anticipated there would be subtle affects; what was really shocking was to find these embryos were turning into liquid," UC Davis Bodega Marine Laboratory Director Gary Cherr said.

Cherr's team co-authored the study released Monday along with the National Oceanic and Atmospheric Administration. He says they found bunker oil from the damaged ship and sunlight proved to be a surprisingly lethal combination for hundreds of thousands of fish embryos in shallow water.

"This can be extremely photo toxic and may be a kind of a new thing that people need to be aware of, that even a small amount of this oil can cause lethality in certain organisms," Cherr said.

Skeptics may question whether other pollutants in the bay are responsible, but Cherr says studies conducted three months after the ship accident and for the next two spawning cycles found what he calls the "chemical fingerprints" of bunker oil.

The watchdog group Baykeeper is working with agencies to prioritize projects to restore the bay and said Monday, "We welcome the new information that will better help us protect the bay from oil spills."

Cosco Busan had a dramatic impact both ecologically and economically.

"Herring is one of the last commercial fisheries inside San Francisco Bay," Cherr said.

The herring population appears to be rebounding. And in September, the shipping companies responsible for the spill agreed to pay more than $44 million to help restore the habitat and fisheries that were damaged.

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