The Development of Laboratory Techniques for the Production of Cultch-Free Spat of the Oyster, Crassostrea virginica

Abstract

Laboratory procedures and the design of new hatchery type equipment for obtaining successful fattening, conditioning, and spawning of Chesapeake Bay oysters in 4 to 6 weeks are described. Two new methods are presented for obtaining free oyster spat, one for relatively clear estuarine areas, and one for areas which have heavy particle loads. The first method, designed for relatively clear estuarine areas, yields free oyster spat two hours after the larvae have set on a substrate by the periodic use of small underwater jets of bay water every two hours in the setting trays. The second method, designed for areas which have heavy particle loads, yields half-inch single oyster spat in approximately three to four weeks by allowing the oyster spat to remain on a substrate Mylar sheet with removal being accomplished by shaking the sheet in a barrel of water.