Sea urchins are ecologically critical grazers whose welfare and population dynamics profoundly affect reef and kelp forest ecosystem health.
Sea urchin welfare exists at two levels: individual welfare during harvesting and ecological welfare of the reef and kelp systems they regulate. As with other echinoderms, the capacity for morally relevant experience in sea urchins is uncertain but warrants precautionary consideration given their behavioral responses to noxious stimuli. At the ecosystem level, the welfare of the fish, marine mammals, and invertebrates that depend on kelp forests and healthy reefs is directly affected by sea urchin population balance — demonstrating how individual species welfare and ecosystem welfare are intertwined.