Sea urchin ranching and aquaculture is growing globally to meet demand for sea urchin roe (uni), with welfare considerations including handling stress, stocking conditions, and slaughter practices for these echinoderms.
The welfare status of sea urchins is scientifically uncertain; their diffuse nervous system and limited behavioural complexity make pain experience difficult to assess. However, precautionary application of welfare principles is appropriate given their capacity for aversive responses. Crowding, inadequate food, and rough handling cause measurable stress responses. Slaughter by live opening for roe harvest without prior stunning is standard practice and causes observable responses. As aquaculture expands, research into urchin welfare needs and appropriate practices would be valuable.