Longsolid & Round Hickorynut Mussels Listed Threatened

March 8, 2023
image_pdfimage_print

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.


Few environmental firms in the country retain EnviroScience’s degree of scientific know-how, talent, and capability under one roof. The diverse backgrounds of our biologists, environmental engineers, scientists, and divers enable us to provide comprehensive in-house services and an integrated approach to solving environmental challenges—saving clients time, reducing costs, and ensuring high-quality results.

Our client guarantee is to provide “Excellence in Any Environment,” meaning no matter what we do, we will deliver on our Core Values of respect, client advocacy, quality work, accountability, teamwork, and safety. EnviroScience was created with the concept that we could solve complex problems by empowering great people. This concept still holds true today as our scientists explore the latest environmental legislation and regulations and incorporate the most up-to-date technology to gather and report data.

EnviroScience expertise includes but is not limited to aquatic surveys (including macroinvertebrate surveys and biological assessments); ecological restoration; ecological services (including impact assessments, invasive species control, and water quality monitoring);  emergency response; engineering and compliance services; endangered mussel surveys; laboratory and analysis; stormwater management; threatened and endangered species; and wetlands and streams (including delineation and mitigation). Further, EnviroScience is one of the few biological firms in the country that is a general member of the Association of Diving Contractors International (ADCI) and offers full-service commercial diving services.