Sea urchin aquaculture is growing driven by demand for roe (uni). Welfare considerations for echinoderms are scientifically uncertain but deserve precautionary attention.
Sea urchin welfare sits in scientifically uncertain territory similar to other invertebrates. Their radial nervous system lacks the centralised pain-processing structures found in vertebrates, and evidence for conscious pain experience is very limited. However, the practice of deliberate starvation in some production systems to improve roe marketability raises welfare concerns even under uncertainty - if sea urchins have any capacity for suffering, intentional starvation represents significant harm. Precautionary welfare consideration supports avoiding production systems that impose unnecessary physiological stress on sea urchins regardless of the certainty about their sentience status.