FISHERIES RESEARCH INSTITUTE,MOA,TAIWAN

Short-necked clam Gomphina veneriformis is one of the commercially important bivalves in Taiwan. The present experiments were conducted to study the effects of salinity on the growth and survival of juvenile short-necked clam. The juveniles were reared indoors or in the greenhouse and fed on Isochrysis spp. and green algae. Water temperature was controlled about 25℃. In the first experiment, we found that the optimal salinity for growth and survival rate of the 31 st days after settlement was 15-25 ppt. In the second experiment, we found that the optimal salinity for the growth in shell length, total weight and survival rate of the 57 th days juveniles (average shell length 0.8180.081 mm) after settlement was 20-25, 20-30 and 20-25 ppt, respectively. In the third experiment, the optimal salinity for the growth in shell length of the juveniles (average shell length 3.910.51 mm) was 25-35 ppt. It seemed that lower than 35 ppt, the optimal salinity increase as the clam grows.
Key words: Gomphina veneriformis, Salinity, Growth, Survival rate