Longsolid & Round Hickorynut Mussels Listed Threatened

FRESHWATER MUSSELS DEEMED THREATENED: March 8, 2023

Asheville, NC—After careful review of scientific data and consideration of public comment, the U.S. Fish and Wildlife Service (USFWS) listed both longsolid (Fusconaia subrotunda) and round hickorynut (Obovaria subrotunda) freshwater mussels as threatened under the Endangered Species Act (ESA). According to the USFWS, they are “also designating critical habitat and tailoring ESA protections to protect these imperiled species from going extinct throughout all or a significant portion of its range in rivers and streams in the eastern United States.”

Longsolid Mussel (Fusconaia subrotunda)The longsolid mussel can live up to 50 years and grow five inches long. It is currently found in ten states (AL, IN, KY, NY, NC, OH, PA, TN, VA, and WV.)

Of the 60 known populations, “48 are in a very limited area with no sign of young mussels growing into adults. Such populations have very low resiliency. This is down from a historical high of 160 populations. The mussel is no longer found in Georgia and Illinois,” according to the USFWS.

Round Hickorynut Mussel (Obovaria subrotunda)The round hickorynut mussel can live up to 15 years and grow three inches long. It is currently found in nine states (AL, IN, KY, MI, MS, OH, PA, TN, and WV.)

Of the 69 known populations, “49 are in a very limited area with no sign of young mussels growing into adults. Such populations have very low resiliency. The mussel is no longer found in Georgia, Illinois, or New York,” according to the USFWS.

USFWS Quote About ESA Protections, Recovery, and PreservationEnviroScience has permitted malacologists throughout the ranges for both species of freshwater mussels with extensive mussel-handling experience.

Not only do we provide field support, but we also provide Section 7 consultation services (Biological Assessment including effects on Critical Habitat) to meet the requirements of the ESA between our clients and their federal nexus.

Visit our Endangered Mussel Surveys page to learn more about EnviroScience’s malacologists and the expert services we provide our clients to ensure compliance with ESA protections and guidelines.


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