SEA CUCUMBER Holothuria scabra SEED PRODUCTION TECHNIQUE
Sea cucumber is one of Indonesia's marine resources which have great potential market; however most of the production relies on natural population. Therefore sea cucumber aquaculture is very important to develop. Although the seed mass production still has many problems, breeding technology one of sea cucumber species Holothuria scabra was successfully done.
Broodstock size around 500 - 1000 g was collected from natural population and preserved in the coastal sea water pond with density 1-2 ind/m2. Feed was relying on natural feeds which were available in coastal sea water pond such as Bacillaryophyta (Centrales & Pennales), Chlorophyta, Cyanophyta, Phyrophyta, Foraminifera, Tintinnides and Zooplankton.
The Holothuria scabra breeding method at MCMA is thermal shock that has proven effectively and safely for brood stock. Thermal shock was done by exposing broodstock in the warm water of the coastal pond with temperature 30-32oC from morning to afternoon, and then put it in the fresh sea water whose temperature between 26-28oC. The sudden different temperature between 3 - 5 oC will be stimulated brood stock to breed.
Breeding activity was done on new moon or full moon, which was usually happened at night time about 6 - 11 pm. It started by releasing male sperm cells continuously and then followed by releasing egg from female for 15 - 30 minutes gradually.
Larva rearing was done in fiber/concrete tank with a volume of 4-10 m3. It can produce 1000-2000 juveniles per cycle (survival rate/SR 0.015%). Feeds which were used during larva rearing are Chaetoceros spp., Nannochloropsis sp. or combination of both with 3x105 cells/ml density. The first nursery activity can be done at semi outdoor or outdoor. Feed given benthic algae which were dominated by diatom. After 2 months of culture, seeds reached the size of 3-5 g. The second nursery activities were also carried out for 2 months with sand as substrate on the base of tank. The feed is dominated by diatom. After 2 months of culture, seed reach a size of 10-25 g. SR in first and second nursery up to 60%.
The close future priority for sea cucumber seed production is increasing SR of the larvae. The SR during larvae culture will give significant value for seed production, since nursery step was already done successfully.