Calif. biologists find invasive oysters (AP)

FREMONT, Calif. - Biologists have discovered giant invasive oysters that could threaten efforts to restore native oyster species in San Francisco Bay. Government staffers and volunteers removed 256 of the exotic mollusks last week after searching the mudflats between the Dumbarton Bridge and the San Leandro Marina, biologists said Thursday. Scientists have not identified the species, which grow up to 9 inches long and in a variety of shapes. They don't know how the exotic oysters got here or how ...