Freshwater mussels are among the most endangered groups of animals globally, with habitat loss and water quality decline causing mass population collapses that affect individual animals and entire ecosystem functions.
Freshwater mussel welfare occupies an uncertain scientific space. The neural complexity of mussels is low enough that pain experience remains genuinely doubtful. But their ecological welfare function — filtering water that hundreds of other species depend on — means that mussel population collapse degrades the welfare of an entire community of organisms that share their habitat. Conservation efforts that restore mussel populations improve the welfare of the ecosystems they inhabit regardless of the mussel welfare question. Protecting clean water and healthy fish populations protects mussels — and the much broader welfare network that depends on clean freshwater ecosystems.