O yster farming is a growing sector within the South African aquaculture industry, and good aquacultural practices are necessary to ensure high quality and economically feasible yields. During their early life-history stages, o yster larvae are highly sensitive to the surrounding environment which impacts on their success during settling and metamorphosis. When the chelating agent, EDTA, is added to seawater, the chelation of heavy metal complexes occurs, resulting in reduced metals being available for biological uptake. The potential impact of EDTA toxicity on development and swimming speed have not been determined.
The optimal larval stocking density is important from an economic perspective however this should not come at the cost of oyster survival and quality. Deformities may occur when larvae are stocked at high densities, resulting in reduced feeding and shell damage due to the contact between larvae. At low stocking densities , yields may negatively impact a hatchery’s economic viability. This study aimed to evaluate the effect of EDTA ( 0,01 mL/L and none) and larval rearing density (10, 20 , and 30 larvae/mL) on the survival, development, and swimming activity of C.gigas larvae over a 48 hour period. Results are currently being analysed and will be presented at the conference. If allowed, an updated abstract will be provided prior to the conference.