Bivalve molluscs are farmed in enormous numbers globally, raising emerging welfare questions about their capacity for suffering and the appropriateness of current farming practices.
Bivalve welfare represents the frontier of animal welfare ethics where scientific uncertainty is greatest and the stakes, given the scale of production, are enormous. The honest scientific position is that we do not know whether mussels, oysters, clams and scallops can suffer. The precautionary principle suggests that as our understanding of invertebrate consciousness evolves, we should be alert to evidence that revises our assumptions. If bivalves do have any capacity for suffering, the scale of their farming would represent the single largest source of farmed animal suffering globally. Maintaining intellectual humility and following the evidence is the appropriate welfare-conscious approach.