Density, growth and survival of Lyropecten (Nodipecten) nodosus (Pteroida : Pectinidae) juveniles in suspended-frame culture in Golfo de Cariaco, Venezuela

The effect of culture density on growth and survival of juveniles was studi ed in the scallop Lyropecten nodosus with intermediate hanging cultures in Golfo de Cariaco, Sucre state, Venezuela, from December 1993 to July 1994. Six spat-densities (7, 15, 30, 50, 125 and 250 scallops/nets) were evaluate d. The initial shell height and dry mass tissue were 9.4 +/- 0.18 mm and 0. 007 +/- 0.0026 g, respectively The specimens were placed into pearl nets an d suspended in a long line at 8 m depth. Growth patterns of somatic tissue were similar, but with different magnitudes and inverse proportionality to culture density. No effect of density was observed on survival. These resul ts suggest that intraspecific competition of cultivated scallops cause stre ss, which affects growth but not survival. We suggest as strategy for the m anagement of culture density, successive density reductions, to obtain in a six months culture (intermediate culture) specimens of 50 mm in shell heig ht in order to start the final culture period.