Effects of salinity and turbidity on development of bamboo sole (Heteromycteris japonicus)

Heavy rain can decrease salinity and increase turbidity of the water in coastal areas, negatively affect-ing the development of organisms, par-ticularly during their early life stages. In this study, the effects of salinity and turbidity on embryos of the bamboo sole (Heteromycteris japonicus) were evalu-ated to improve understanding of its tol-erance to global climate change. Three experiments were carried out over a 7- d period. In the first experiment, embryos of bamboo sole were exposed for 3 h to 1 of 6 salinity levels (14-34). Low salinity levels (14 and 18) resulted in signifi-cantly shorter total lengths of newly hatched larvae in comparison with larval sizes in treatments with higher salinities, but no significant differences were observed in hatching rate and lar-val survival rate among treatments. In the second experiment, embryos were exposed to turbidities of 0, 100, 300, 500, and 700 nephelometric turbidity units for 3 h. Turbidity significantly decreased hatching rate, survival rate, and total length and increased onset hatching time and percentage of abnor-mality. In the third experiment, embryos were exposed to different combinations of salinity and turbidity. The interaction effect of salinity and turbidity on total length of newly hatched larvae was sig-nificant. These findings indicate that embryo development of bamboo sole was more affected by changes in turbid-ity than by changes in salinity.