Methods of growing Mercenaria mercenaria from postlarval- to preferred-size seed for field planting

Research on Mercenaria mercenaria has established that 8-mm clams survive better in field planting than smaller sizes. Because of space, equipment, manpower, and other constraints, commercial hatcheries are often unable to fill the demand for larger seed. Most hatchery operators prefer to sell smaller (2–4 mm) clams, and so structure their price schedules to encourage the sale of smaller seed. It then may become more economical for the clam planter to operate a nursery of postlarval- to field-size seed. A number of methods and some of the problems that are associated with these methods are discussed.