Effects of Salinity and Temperature on Survival and Development of Larvae and Juveniles of the Mud Crab, Scylla serrata (Crustacea: Decapoda: Portunidae)

Abstract

An investigation was conducted to determine salinity and temperature effects on the survival and development of larvae and juveniles of the mud crab, Scylla serrata. Zoea, megalopae, and juveniles were reared at various salinity and temperature combinations: 15, 25, 35, and 45 ppt for zoea; 5, 15, 25, 35, and 45 ppt for megalopae; and 0, 5, 15, 25, 35, and 45 ppt for juveniles, at 20, 26, and 32 C. Salinity and temperature affected the survival of the zoea larvae, and there was an interaction between salinity and temperature. Salinity and temperature also affected the survival of megalopa and juveniles, but there was no interaction between salinity and temperature. There was high survival and metamorphosis on zoea reared at 25–35 ppt at 26 and 32 C. Megalopae developed to juveniles at 15–45 ppt at 20, 26, and 32 C. Juveniles survived and developed at 5–45 ppt at 20, 26, and 32 C. Salinity and temperature also affected the development and molt duration. Development was rapid at 25 and 35 ppt, at 32 C, but delayed at 15 and 45 ppt, at 20 and 26 C. Zoea benefited gradual transfer to 15 and 45 ppt but megalopa and juveniles did not. As the larvae grew, there was tolerance to wider salinity and low temperature.