THE CULTURE OF THE SOUTHERN BAY SCALLOP IN TAMPA-BAY, AN URBAN FLORIDA ESTUARY

Bay scallop, Argopecten irradians concentricus (Say), stocks were coll ected from a Homosassa (Florida) population in 1991 and were kept in s eawater from Bayboro Harbor on Tampa Bay, an urban Florida estuary. Th ey were fed with Isochrysis galbana and Tetraselmis sp. Spawning was a llowed to occur after the scallops became ripe. The hatching rate of t he F-1 eggs to D-shaped larvae was 72%. Settlement and metamorphosis b egan 11 days after fertilization. When spat reached a shell height of 0.8 mm in the laboratory, they were placed with substrates into 300 an d 800 mu m mesh bags, and later in lantern nets, suspended from a dock in Bayboro Harbor. The F-1 scallops successfully survived to gonad ma turity in the fall of 1992, with mean (so) shell height of 49.8 (4.0) mm on 6 September 1992. The scallops experienced heavy mortality durin g the summer, partially as a result of heavy fouling. From early Augus t to October of 1992, F-1 scallops grown in Bayboro Harbor were succes sfully spawned in the laboratory. Growth and survival of the F-2 scall ops were comparable to those of the F-1 scallops. Results have shown t hat bay scallops can complete an entire life cycle in an urban estuary such as Tampa Bay, and a hatchery for bay scallops on the estuary can assist in the restoration of the population. Fouling represents a pos sible severe limitation and alternatives to caging for grow-out should be considered.