Growth and Survival of Hatchery-Reared American Oysters Set on Three Types of Cultch and in Bon Secour Bay, Alabama

Hatchery-reared American oysters (Crassostrea virginica) were set on three types of cultch (Mylar(R) sheets, crushed oyster shells, and whole oyster shells) and were observed for 157 days in indoor raceways. Greatest growth was observed in the cultch-free oysters originally set on Mylar(R). The least growth was observed in oysters set on crushed oyster shell. The growth of hatchery-reared oysters, set on whole oyster shells, was significantly greater than that of oysters on a natural reef. Hatchery-reared oysters were planted on 14 December 1978 in two 0.5-hectare plots in Bon Secour Bay, Baldwin County, Alabama. The accumulative mortality on both plots averaged about 99% after 3 months; 7 months later, no planted hatchery-reared oysters were found on the plots.