Assessment of blacklip rock oyster, Saccostrea lineage J, spat growth and survival in recirculating upweller and downweller nursery systems

ABSTRACT The blacklip rock oyster, Saccostrea lineage J, has the potential to support new aquaculture developments throughout its range in the tropical Indo-Pacific region, but lack of research investment in understanding basic biology has been a key failure point in the past. This study assessed Saccostrea lineage J spat growth and survival in downweller and upweller nursery systems, with the aim of establishing baseline biological information and evaluating spat performance to support commercialisation efforts. Downweller and upweller nursery systems were similarly effective at rearing spat, with mean dorsoventral measurement in both systems reaching a 5 mm deployment size at 59 days post hatch. Growth rates reported in this study of 0.19 and 0.20 mm day−1 in the downweller and upweller, respectively, are comparable to other hatchery-produced tropical and subtropical bivalve spat. Based on the results of this study, it is recommended that spat be held in nurseries for approximately two months to reach a 5 mm deployment size. The information obtained in this study is the first documentation of Saccostrea lineage J spat growth and survival, and the methods used provide a basis for commercial production of this species.