Freshwater mussels including the critically endangered freshwater pearl mussel face population collapse; their welfare status reflects river ecosystem health.
Freshwater pearl mussels in degraded river habitats experience chronic physiological stress from poor water quality and are likely experiencing ongoing population failure rather than stable existence. Whether mussels experience subjective suffering is uncertain, but the precautionary principle and their ecological importance warrant significant conservation welfare attention. The welfare of mussels is inseparable from the health of the river ecosystems they depend on - improving water quality and restoring salmon and trout populations benefits the whole river community.