Bivalve molluscs occupy a unique position in the welfare debate — their sentience is uncertain but philosophical precaution and harvesting practice welfare considerations still apply.
Bivalve welfare represents an interesting philosophical boundary case. The mainstream scientific and philosophical view is that oysters, clams, and mussels are very unlikely to be sentient based on their neurological simplicity. Peter Singer and others who are generally strict in their animal ethics considerations have suggested bivalves may be ethically acceptable to consume. The practical welfare consideration for bivalves therefore shifts to habitat effects of dredging on other animals and the broader ecosystem welfare of their harvest context. Aquaculture bivalves grown on lines or in cages have minimal environmental impact and present the most welfare-unproblematic seafood choice.