Freshwater mussels are among the most endangered animals globally and play vital roles in river ecosystems. Questions about their sentience add a welfare dimension to their conservation story.
Freshwater mussels occupy an unusual position in welfare discussions: they are among the most endangered animals globally, yet their capacity for sentient experience is scientifically uncertain. They possess basic mechanoreceptors and respond to stimuli, but the presence of pain experience in the philosophical sense requires neural complexity that mussels do not clearly possess. The conservation case for freshwater mussel protection is compelling regardless of sentience questions: as ecosystem engineers that filter water and create habitat structure, their decline impoverishes river ecosystems for all inhabitants. Conservation programs that restore water quality, reconnect habitats, and protect host fish populations address the ecological conditions that freshwater mussels require for survival and support broader river ecosystem health that benefits all riverine species.