sandfish goes through 6 stages of growth before maturing into an adult. This starts when the adults spawn. After a day the fertilized eggs develop into a first planktonic phase, a gastrula, then after two days it becomes a auricularia, the feeding planktonic stage. Within the next 14 days the sandfish will enter a non-feeding doliolaria stage and a final planktonic pentactula stage, before becoming juveniles and settling into the sea grass meadows to mature. Ecology Distribution The species can be found in the Indo-Pacific region, from east Africa to the eastern Pacific. Some have been found in the Persian Gulf, Iran. They are typically restricted to latitudes between 30° N to 30° S, due to it being a tropical species. Habitat The sandfish inhabits shallow tropical waters, <20 m deep. They prefer seagrass meadows and muddy bottomed substrata with high nutrient levels due to their diet preference. They do have a tolerance for lowered salinity, down to 20 ppt, such as that found in brackish water. Sandfish play a key role in the health of their habitat; like most sea cucumbers H. scabra are bioturbators and play a key role in reworking the sediment and ensuring that organic matter is evenly distributed for the ecosystem to function, and have a subsequent diet of detritus and other microorganisms. Behavior The sandfish exhibits some distinct behaviors. Their burrowing behavior varies as they mature, with younger sandfish responding to changes in light and coming out in darkness. Older sandfish are more sensitive to changes in temperature and will burrow to escape the cold. Sandfish are particular about sediment size and type, settling in fine sand and muddy substrates high in nutrients. Like all sea cumbers, H. scabra exhibits defensive vomiting, where they expel their internal organs to distract predators while they escape. Male and females have distinct mating behaviors; when they spawn males erect their bodies and sway from side to side as they release sperm into the surrounding water. Shortly after, females will erect their bodies and send eggs into the water with the sperm in a short, forceful burst. Use as food The sandfish has been eaten by man for over 1000 years. About twenty other species of sea cucumber are also consumed but the sandfish is the species most often used. In the 1990s it was being sold dried as beche-de-mer for up to US$100 per kilogram. Harvesting sandfish