Evaluation of a partial flow-through culture technique for pearl oyster (Pinctada margaritifera L.) larvae

Abstract

This study evaluated a partial flow-through culture system for larvae of the blacklip pearl oyster (Pinctada margaritifera, L.). Water flowed through the 500-l larval rearing tanks for 12 h day−1 and provided a 100% water exchange during this period. Larvae were prevented from leaving the culture tanks by a conical mesh screen placed over a central stand-pipe. Tanks were completely drained every 7 days to prevent build-up of debris on the tank bottom. First `eyed' larvae were seen on day 23 and, by day 28, approximately 5% of the larvae initially stocked had reached the `eyed' stage and were removed into settlement tanks. Larval growth and survival compared favourably with previous studies in which P. margaritifera larvae were cultured using conventional static culture methods. However, when compared to static culture systems, the partial flow-through system described in this study requires less labour and, as such, is likely to be more appropriate for hatchery culture in developing Pacific nations.