Green Porcelain Crabs (IMAGE) Georgia Institute of Technology Research News Caption Two green porcelain crabs are shown among oyster shells. The non-native crabs are filter feeders and may compete with oysters and mussels for food. Credit Photo: Alan Wilson Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.