Preliminary studies to culture mangrove oysters, Crassostrea tulipa, in Sierra Leone

Large quantities of wild mangrove oysters Crassostrea tulipa exist in the intertidal zone of the rivers and estuaries of Sierra Leone. Typically, the wild mangrove oysters are small due to crowding and stress induced by the high ambient temperatures and lack of food at low tide when the oysters are out of water. The wild oysters measure on the average 2.5 cm and weigh 1.5 g for a 2-year growing period. Preliminary studies have been made since 1974 to identify viable culture techniques that will increase the yield (growth rate and size) of mangrove oysters. Suspended culture (rack and raft) was found to be most promising with rafts producing an average 7-cm and 7-g oyster in 7 months. Biological work summarized includes plankton, fouling and bacteriological studies. Some cost-benefit studies are also included. © 1982.