Water temperature and salinity synergistically affect embryonic and larval development of the tropical black-lip rock oyster Saccostrea echinata

Poor larval survival is a bottleneck to commercial hatchery production of the tropical black-lip rock oyster, Saccostrea echinata. This study investigated the synergistic effects of water temperature and salinity on embryonic and larval development across each major larval life stage. Results showed that water temperature and salinity have a significant effect on embryonic development of S. echinata and that embryos did not develop below 17 °C and 14 psu. Survival was high (55–100%) across all treatments and larval stages, and shell size was used primarily to determine larval response to treatments. Larval shell size increased as water temperature and salinity increased, reaching optima at 32 °C and 23 psu for D-veligers (mean DVM 78.18± 0.85 μm), at 32 °C and 26 psu for umbonate larvae (mean DVM 183.40 ± 2.60 μm), and at 32 °C and 29 psu for eyed larvae (mean DVM 249.64± 3.22 μm). It is recommended that S. echinata embryos and larvae are cultured within 28–32 °C and at salinity optima for each larval stage: embryo development at 32 psu, D-veligers and umbonate larvae between 23 and 26 psu, and eyed larvae between 28 and 30 psu. This is the first investigation of the combined effects of water temperature and salinity on S. echinata and provides valuable information to accelerate commercial aquaculture of this tropical species