Tropical Crab Invades Georgia Oyster Reefs - But The Long-term Impact Can't Be Predicted

A dime-sized tropical crab that has invaded coastal waters in the Southeast United States is having both positive and negative effects on oyster reefs, leaving researchers unable to predict what the creatureus long-term impact will be. Unlike native crabs that eat baby oysters, mussels and fish, the green porcelain crab Petrolisthes armatus is a filter feeder, extracting its food from the water much as oysters do. The fast-reproducing invader therefore isnut directly attacking oyster populations, though it may be competing with them for food u" and may impact the predators that normally attack the oysters...