Sea urchin aquaculture is growing as wild fisheries decline. Their capacity for pain and suffering is debated, but evidence of nociception makes welfare consideration relevant to responsible production.
Sea urchin sentience remains scientifically uncertain. Their nervous system lacks centralized brain structures associated with conscious pain in vertebrates, but they do respond to harmful stimuli and show behavioral changes after injury. The precautionary principle and the growing recognition of invertebrate welfare suggest taking a cautious approach to sea urchin production conditions. Stocking density, water quality, and killing methods all have potential welfare relevance.