Low Tide (IMAGE) National Oceanic and Atmospheric Administration Caption Low tide at Chocolate showing broken oyster shells randomly dispersed over sand bottom. Sapelo Island National Estuarine Research Reserve. Credit Courtesy of National Oceanic and Atmospheric Administration/Department of Commerce. Usage Restrictions Image credit to National Oceanic and Atmospheric Administration/Department of Commerce is required. 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.