Sea cucumbers are critical ecosystem engineers in coral reef and seabed environments, and their overharvesting is destabilizing marine ecosystems that support vast numbers of other species.
Whether sea cucumbers experience suffering in a morally significant sense is highly uncertain given their simple nervous systems. The welfare significance of sea cucumber depletion is primarily ecological — their removal destabilizes the nutrient cycling and sediment processing functions that coral reef and seabed ecosystems depend on. These ecosystem services support the welfare of countless fish, invertebrates, and marine mammals that depend on healthy reef and seabed environments. The collapse of sea cucumber populations is therefore a welfare issue for the broader marine community even if individual sea cucumber welfare is uncertain.