The welfare status of mussels, oysters, and other bivalves is a contested question in animal welfare science — they lack a centralised brain but may have nociceptive responses.
The welfare status of mussels and oysters sits at the frontier of animal sentience research. Current scientific consensus leans toward low probability of subjective suffering in bivalves, but genuine uncertainty remains. The precautionary principle would suggest minimising potential suffering even at low probability, particularly during harvesting and processing. This is an area where welfare science may provide greater clarity in coming years, and where intellectual humility is appropriate in making dietary and policy recommendations.