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High mortality of sandfish Holothuria scabra broodstock is one of the main problems in sea cucumber hatcheries. Broodstock collected from wild are very difficult to keep alive for long periods because the broodstock readily eviscerate. One cause of evisceration and death is probably due to the presence of peanut crabs Pinnotheres halingi in body cavity as commensal. This study aimed to analyse the mortality of sandfish due to the presence of peanut crabs as commensal. Sandfish samples were collected in Liukang Tupabbiring Utara District, Pangkep Regency in South Sulawesi, Indonesia. During the study, 139 sandfish were observed in rearing nine tanks at the laboratory. The results of this study are not strong enough to state that peanut crab is a symbiotic commensal or parasite. The peanut crab is thought to have turned into a predator when it starved. Peanut crab malignancy as a predator can cause the death of 139 sandfish in 92 days. This is thought to be the reason why broodstock is very difficult to rear for a long period in a controlled tank in a laboratory or hatchery.

The supply of broodstock is a critical limitation on aquaculture of the commercially important sea cucumber Holothuria scabra. Previous research reported that H. scabra mature at a size of more than 450 g. This size is questionable because biologically primitive organisms such as H. scabra mature relatively early. This study aimed to analyze the size at first maturity of H. scabra. The first sexual maturity was analysed by dividing the H. scabra by weight with 25 g weight class intervals, resulting in 12 weight groups. The size at first sexual maturity was determined using mature H. scabra (Stages III, IV, and V). The first maturity of H. scabra was reached at a smaller size than previously reported, from 178 H. scabra that were observed, the first sexual maturity is achieved at 42 g gutted body weight. Small H. scabra potentially used as broodstock, which will produce H. scabra seeds in hatcheries. Although small in size, H. scabra mature can reproduce, of course, with a smaller reproductive capacity. Small size at the first sexual maturity offers the potential for dramatic improvements in the procurement of broodstock stock, by providing a much more accessible supply of H. scabra prospective broodstock.

The sandfish Holothuria scabra is a benthic animal of high ecological and economic value. The high economic value of sandfish has led to declining populations due to overfishing. Initiatives to improve sandfish production have included restocking, sea-ranching and aquaculture (captive breeding and grow-out). These initiatives require a supply of animals (seed and/or broodstock) that often originate far from the location where they are needed. This calls for a good transportation system so that the sandfish arrive in good condition. This study aimed to assess the evisceration rate of sandfish transported using open and closed transportation modes. During the study, different modes of packing, density, transportation time, and holding time were evaluated. This study indicated that delivery using open systems gave poor results; besides being less practical, post-transport evisceration was very high. The ratio of oxygen and water and the packing density did not appear to affect the sandfish evisceration rate. Evisceration seemed to be triggered by the presence of dead and decaying sandfish in the bag. Sandfish that survived transportation generally recovered swiftly after being placed in a pre-prepared holding tank. The transported sandfish were used for multitrophic aquaculture and the post-transport survival ratio was very high.