Development of an appropriate nursery culture system is critical in improving the survival of post-release sandfish juveniles within different production systems. This study evaluated the growth performance of sandfish juveniles reared in floating hapa enclosures and advanced nursery culture pens by small-scale grouper farmers within rural coastal communities in Bolinao, northwestern Philippines.
Growth performance and survival of sandfish juveniles reared in floating hapas were high (Table 1a). From an initial average weight of 0.03±0.002 g, sandfish attained an average weight of 4.28 ± 0.23 by day 66. Highest growth rates of sandfish juveniles reared in floating hapas was recorded by day 66 at 0.09 ± 0.02 g day-1 while lowest growth rate was recorded by day 24 at 0.04 ± 0.01 g day-1. Additionally, survival of sandfish juveniles at the end of the monitoring period was high at 56.8 %. Likewise, growth performance and survival of sandfish reared in the advanced pens were high (Table 1b). Highest growth rate of sandfish reared in the advanced pens was recorded by day 86 at 0.89 ± 0.1 g day-1 while the lowest growth rates was recorded at the end of the study at 0.15±0.3 g day-1. Despite the decreased in growth rates, sandfish attained 102.7±6.2 g after 157 days of rearing in the grow-out pens. This study showed the viability of releasing sandfish juveniles directly into advanced nursery pens as indicated by high growth performance and apparent survival of sandfish reared in the pens. Additionally, results of the study provide basis for the utilization of ocean-based advance nursery and development of a production model involving small-scale aquaculture farmers to increase sandfish juvenile production and ultimately the realization of the socio-economic benefits of sea cucumber mariculture.