How do sea cucumbers affect the seafloor?
Sea cucumbers are soft-bodied echinoderm relatives of sea stars that process organic material on the seafloor.
Body plan, feeding and the marine environment
Modified tube feet around the mouth collect sediment or suspended particles. As sand and mud pass through the gut, organic matter and microbes are removed and processed sediment is released. This bioturbation can affect oxygen and nutrient movement in the seabed. Tiny calcareous pieces provide internal support. Relationships among marine invertebrates cannot be inferred from appearance alone because similar forms can evolve in different lineages. Pressure, light, temperature, salinity and currents shape feeding and movement. Laboratory observations may not represent the full behavior seen in nature.
Ecosystem function, defense and conservation
Some species eject sticky threads or portions of internal organs when threatened and later regenerate them. This defense is not limitless and has an energy cost. Heavy commercial harvest can reduce slow-growing populations and alter sediment processing, so sustainability must be assessed by species and place. These animals may shape ecosystems through filtration, decomposition, sediment mixing or reef building. Warming, deoxygenation, acidification, plastic, seabed damage and overharvest are considered together. Conservation targets habitat processes as well as individual species.