THE EFFECT OF SALINITY ON SURVIVAL AND GROWTH PERFORMANCE OF GOLDEN TREVALLY Gnathanodon speciosus JUVENILES

The experiment was performed to determine the effect of salinity on survival and growth performance for Golden trevally Gnathanodon speciosus juveniles during nursery phase.  Before that, G. speciosus juveniles were introduced to abrupt changes of salinity from 20ppt to 0, 5, 10, 15, 20, 25, 30, 35, 40 and 45ppt.  The salinities with mortality rate less than 50% within 72 hours were used in the study to find out the survival rate and growth performance of the juveniles during 60 days of nursery period.  The salinities were 10, 15, 20, 25, 30, 35 and 40ppt.  The Fingerlings exhibited highest survival rate at 20ppt (92.67%) followed by 35ppt (91.67%) and the lowest survival rate was at 10ppt (63.67%) whilst the Specific Growth Rate (SGR) showed highest at 15ppt (0.11g/day) followed by 20ppt, 25ppt, 30ppt, 40ppt, 10ppt and 35ppt. Somehow the differences among treatment were not significant (P > 0.05). The juveniles grew and survived satisfactorily at salinities range from 10-40ppt, implying that this species can be cultured successfully at wide range of salinity.  G. speciosus can be considered as an ideal species to promote, in view of current and future climate variables as more and more coastal areas are going to be vulnerable to saline water inundation

Keywords: Salinity, Golden trevally, survival, growth performance