Randal L. Walker

Effects of Temperature and Salinity on Growth of Juvenile Black Sea Bass, with Implications for Aquaculture

Abstract The black sea bass Centropristis striata has recently gained popularity in the live seafood markets of the northeastern United States. Fish farmers need instruction on optimizing environmental parameters for the growth of black sea bass. In this study, optimal temperature and salinity were determined experimentally for the growth of juvenile black sea bass (initial mean weight, ∼9.2 g). The temperature experiment compared growth at temperatures of 15, 20, 25, and 30°C; the salinity experiment compared growth at 10, 20, and 30‰ salinities. Both of these experiments were performed in closed aquaria. At the end of the temperature experiment (6 weeks), Tukeys Studentized range test (α = 0.05) showed that fish reared at 25°C were significantly larger than those reared at 20°C and 30°C. All of these temperatures produced significantly larger fish than did the 15°C treatment. At the end of the salinity experiment (12 weeks), Tukeys Studentized range test (α = 0.05) showed that salinities of 20‰ and 30...

GAMETOGENIC CYCLE OF THE PONDEROUS ARK, NOETIA PONDEROSA (SAY, 1822), FROM CEDAR KEY, FLORIDA

Abstract The gametogenic cycle of the ponderous ark, Noetia ponderosa (Say, 1822), was studied in a Cedar Key, Florida population between March 2001 and January 2003. Ponderous arks are dioecious, and no hermaphrodites were found in this study (n = 592). The sex ratio of females to males was 0.84:1.00, but was not significantly different from parity. On the Gulf coast of Florida, the ponderous ark dribble spawns over most of the year, peaking in the summer and fall months and with the least spawning activity occurring during the spring when gametes are maturing. A small percentage (5.2%) was found infested with an undescribed digenetic trematode. The Cedar Key area has an important commercial hard clam (Mercenaria mercenaria) aquaculture industry, and the implications of these findings on the potential for its diversification based on this species are discussed.