Freshwater pearl mussels are among Europe's most endangered species, dependent on clean, fast-flowing rivers and salmon populations. Their decline reflects widespread river degradation with consequences for entire river ecosystems.
Freshwater pearl mussel welfare sits at the intersection of conservation and bivalve sentience debates. As with other bivalves, the evidence for sentience is limited — neurological architecture does not support conscious experience as understood in vertebrates. However, their extraordinary longevity (100+ years), ecological significance, and near-extinction status make their conservation a moral priority independent of sentience questions. Their decline reflects river ecosystem health — restoring mussel populations requires addressing agricultural runoff, riparian vegetation loss, and salmon population recovery. Captive rearing programmes, which cultivate juvenile mussels for river re-introduction, are welfare-relevant to the extent that husbandry conditions affect mussel health and survival. The survival of each individual carries conservation weight given the tiny size of remaining populations. Protecting freshwater pearl mussels protects entire river ecosystems including numerous other species.