Sea urchin aquaculture is a growing sector with limited welfare science, requiring precautionary welfare considerations for these spiny marine invertebrates.
Sea urchin welfare occupies the same uncertain territory as bivalve welfare — these are animals with nervous systems sufficiently different from vertebrates that confident sentience claims are not supported by current science. However, the precautionary welfare principle suggests minimum standards for water quality management and careful handling are appropriate even in the absence of confirmed sentience. Sea urchins show physiological stress responses to handling and environmental changes that may or may not involve subjective experience. Applying minimal welfare standards — good water quality, careful handling, and avoidance of unnecessary injury — costs little and provides precautionary protection if sentience is eventually established.