Scallops and other bivalves are harvested by bottom trawling which causes significant collateral damage to marine ecosystems and raises questions about bivalve sentience.
The question of bivalve welfare is genuinely uncertain. Scallops have complex sensory systems and behavioral responses to threats suggesting some form of experience. However, they lack the centralized nervous system of vertebrates. The welfare concern is more clearly about the destruction of marine habitats through trawling, the suffering of bycatch species, and the precautionary principle around animals whose sentience is unclear rather than confirmed absent.