Because of the decline of mussels throughout North America, many National Park System units are destined to become important refuges for this endangered group of animals. Yet, data on the abundance, distribution, and health of mussel populations in National Park System units are lacking. The National Park Service has a critical role in the survival and recovery of freshwater mussel species.
Mussels have important functions in aquatic environments.
They are a link in the food chain and help to maintain water quality. Because they are long-lived and particularly sensitive to changes in water quality, mussels are important indicators of aquatic ecosystem health. The disappearance of mussels from a river or lake often signals that other aquatic species are at risk. North American freshwater mussels have an extraordinary life history and reproductive adaptations. An important feature of their life history is the unique and complex need of the larvae for a fish host to metamorphose from the larval parasitic stage to a free-living juvenile mussel.