ALBANY, NY.- The New York State Museum has been awarded an $713,000 cooperative agreement from the U.S. Environmental Protection Agency (EPA) to lead a five-year effort to restore freshwater mussel populations in the Lower Grasse River. The project will return nearly 500,000 rescued mussels to restored habitat while advancing scientific research that can inform freshwater restoration efforts across New York and beyond.

Museum scientists have begun evaluating restored river habitat and carefully returning freshwater mussels to selected areas. There, the mussels will establish new self-sustaining populations, known as “founder colonies,” designed to naturally reproduce and help rebuild one of New York’s most diverse freshwater mussel communities.

Dr. Denise Mayer, New York State Museum Curator of Malacology said, “For years, hundreds of thousands of these mussels have been waiting in protected holding areas for the opportunity to return home. Returning them to the Lower Grasse River is about rebuilding a healthier river system that supports wildlife, improves water quality, and benefits communities across New York. By carefully reestablishing these populations and studying how they recover, we’re generating knowledge that will help guide freshwater conservation efforts statewide and ensure that the state’s rivers remain resilient for generations to come.”





For decades, PCBs from past industrial operations accumulated in the sediment of the Lower Grasse River near Massena, contaminating a stretch of river that supports fish, wildlife, and one of New York’s most diverse freshwater mussel communities. The federal Superfund cleanup that followed was essential to the river’s recovery, but the work also threatened the mussels living in the riverbed. To protect them, scientists and partner agencies rescued nearly 500,000 mussels before and during remediation, preserving a vital part of the river’s ecosystem for eventual return to restored habitat.

Scientists identified 16 native unionid mussel species among the rescued animals, including seven designated by New York State as Species of Greatest Conservation Need (SGCN).

The project is supported by $713,000 from the U.S. Environmental Protection Agency and $140,000 in matching funds from the New York State Department of Environmental Conservation, for a total of $853,000 in funding. It will be conducted in partnership with the New York State Department of Environmental Conservation, the Saint Regis Mohawk Tribe, and the New York State Water Resources Institute.

State Department of Environmental Conservation Assistant Deputy Commissioner for Natural Resources Frankie Molinari said, “DEC is committed to protecting New York's native mussel diversity and aquatic resources in the St. Lawrence region and beyond. We are excited to continue collaborating with the New York State Museum and Saint Regis Mohawk Tribe on the next phase of this unique and innovative mussel recovery project that will help restore the Lower Grasse River ecosystem after major disturbance.”

Jessica L. Jock, Remediation and Restoration (R&R) Program Manager for the Saint Regis Mohawk Tribe Environment Division, said, “This project will continue to advance our State and Tribe co-managed native mussel species recovery targets outlined in the Recovery Plan for the lower Grasse River Freshwater Mussel Community. Founder colonies is an important component to achieve restoration of our Degradation of Benthos beneficial use impairment in the St. Lawrence River Area of Concern (AOC) at Massena/Akwesasne. We are excited to have Dr. Denise Mayer and New York State Museum as one of our established partners in native mussel research lead this critical piece of the Plan.”

Freshwater mussels are among North America’s longest-lived animals and are essential to healthy river ecosystems. Often called nature’s water filters, they remove suspended particles from the water, recycle nutrients, stabilize streambeds, and improve habitat for fish and other aquatic life. Because they are highly sensitive to pollution and habitat degradation, healthy mussel populations are also important indicators of healthy rivers.

By leading the return of freshwater mussels to restored habitat, the New York State Museum is helping transform one of New York’s largest aquatic wildlife rescue efforts into a long-term conservation success. The project reflects the power of Museum research, sustained partnerships, and strategic investment to restore ecosystems and protect New York’s natural heritage for future generations.