Low Tide (image) National Oceanic and Atmospheric Administration Share Print E-Mail 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. Share Print E-Mail 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.