January 16, 2014
The U.S. West Coast’s native Olympia oysters face a greater threat from invasive predatory snails as climate change raises the acidity of oceans, research by the University of California, Davis found.
Predatory snails ate 20 percent more young bivalves when both species were raised in ocean conditions forecast for the end of the century, according to a university report published in the journal Proceedings of the Royal Society B. Oysters raised by the researchers under the high carbon dioxide conditions forecast for 2100 stayed smaller, while the snails were not affected and as a result ate more shellfish.
“It’s like if you go out for tacos,” Eric Sanford, professor of evolution and ecology at UC Davis and lead author of the study, was cited as saying. “If the tacos are smaller, you’re going to eat more of them.”
Olympia oysters were once so common in San Francisco Bay that they were a cheap food during the California Gold Rush, before the population collapsed from overfishing in the late 1800s, never to recover, the university wrote.