The Species
Sandfish is indigenous to Seychelles waters and as such is permitted for aquaculture production. This species has a high market value, and a growing demand which cannot be met by capture fisheries as its wild populations have become overexploited. Aquaculture of sandfish to supply the market is thus an opportunity for economic development.
Sandfish is the most widely cultured tropical sea cucumber species. Its reproductive cycle in captivity is well understood, and hatchery, nursery and grow-out technologies and practices have been well-developed. It is demonstrated to grow well in a variety of culture systems, including pond culture and sea ranching.
Sea ranching inevitably results in enhancements of natural populations, due to spill-over and larval recruitment effects. Sea ranching of sandfish in the Seychelles thus has the potential to assist in the recovery of the overexploited population.
Environmental and Oceanographic Conditions
Yields from sea ranching are dependent on identifying optimum sites. High food availability is required for growth and survival, and to prevent sandfish moving away from the ranching area. Seychelles waters offer optimum habitats and environmental conditions for the survival and growth of ranched sandfish
A number of potential sites have been identified that are suited to farming of sandfish, including on the outer islands; there is an opportunity for both pond-culture and small-scale sea ranching on Coëtivy, and for large-scale sea ranching on Poivre Island.
Seychelles waters are also well suited to sea-based cage culture of marine finfish species, and longline culture of pearl oysters, due to ideal oceanographic conditions, which allows for Integrated Multi-Tropic Aquaculture (IMTA). The substrate under finfish cages and pearl oyster longlines serves as an ideal location for ranching of sandfish as excess organic matter from cages (such as faeces, and uneaten food in the case of finfish) can provide a nutrient-rich environment for high growth and survival rates in sandfish. Ranching of sandfish below sea cages and longlines also allows for bioremediation of the sediments below these cages and improves the sustainability of finfish farming.
Access to Markets
Seychelles’ level of transport infrastructure and location in the middle of the western Indian Ocean makes it ideal for aquaculture production; it has access to markets in Europe, the USA and Asia, via air and sea transport, and is able to receive imports of supplies, such as feed and technical equipment, from high-quality suppliers around the world. It also has access to local markets as products can be transported within and between islands.
Seychelles is among the top exporters of sea cucumber products to Asian markets, and a high-value export market for high-quality products is already established. This provides an opportunity to increase the supply of products to these markets, while increasing the value with the addition of increased quantities of valuable sandfish bêche-de-mer.