Filtration rate and bioremediatory potential of the tropical blacklip rock oyster Saccostrea lineage J

Abstract

The tropical blacklip rock oyster Saccostrea lineage J is an emerging aquaculture species displaying fast growth rates, large sizes and resilience to fluctuations in temperature and salinity, all characteristics that suggest it would be well-suited to bioremediatory applications. To investigate their bioremediatory potential, the present study aimed to (1) determine the influence of temperature (20, 24, 28, 32°C) on the filtration rate of Saccostrea lineage J and (2) describe and quantify uptake in total nitrogen (TN), total phosphorus (TP), total suspended solids (TSS) and chlorophyll a (chl a), using prawn pond effluent and 2 levels of oyster stocking density. The results demonstrated that higher water temperatures promote a faster filtration rate and identified an optimal performance range of 24 to 32°C for a filtration rate of 12.68 to 15.20 l h-1 g-1. In addition, the highest density (0.66 oysters l-1) of stocked oysters resulted in significant reduction of all water quality parameters, with TN reduced by 13%, TP by 16%, TSS by 95% and chl a by 29% when compared to unstocked controls after 3 h. Tissue analysis of 10 oysters with a mean whole weight of 75.4 g revealed a mean of 0.09 g of nitrogen per oyster. Scaling these values suggests that 1.20 kg of nitrogen is removed per tonne of harvested oysters. This study is the first to investigate the bioremediatory potential of Saccostrea lineage J and demonstrates their potential to improve aquaculture wastewater treatment practices and bioremediation.