Sea urchin farming is expanding globally to supply the lucrative roe (uni) market. Whether sea urchins are sentient and what welfare standards should apply is an emerging question.
Sea urchin welfare sits at the outer boundary of current animal ethics, where evidence for sentience is weak but the scale of production and the precautionary principle together suggest consideration. Sea urchins lack a centralised brain but have a complex nervous system capable of coordinated responses to stimuli. Current understanding does not support strong claims of sentience, but scientific uncertainty combined with production at scale warrants attention. As the industry grows, developing welfare considerations alongside it - rather than retroactively - would be more effective. The precautionary approach suggests minimising handling stress and optimising environmental conditions even where certainty about sentience is absent.