Endangered status proposed for three mussel species
Three freshwater mussel species have been proposed for designation as endangered species under the federal Endangered Species Act. The Cumberland moccasinshell, Tennessee clubshell and Tennessee pigtoe all occur in the Tennessee River Basin, while the Cumberland moccasinshell and Tennessee clubshell are also found in the Cumberland River Basin.
“The southeastern United States is home to a tremendous diversity of freshwater life, with the global center of mussel diversity being right here,” said Acting Southeast Regional Director of the U.S. Fish and Wildlife Service Mike Oetker. “The state of freshwater mussels often reflects the quality of water. The listing of these mussels is a reminder of the importance of our role in keeping water clean.”
Today, there are 65 known populations of Cumberland moccasinshell, with 87 populations believed extinct; 64 known populations of Tennessee clubshell with 83 believed extinct; and 63 known populations of Tennessee pigtoe, with 51 believed extinct.
Because they are sensitive to pollution, vibrant mussel populations typically reflect a healthy stream. Additionally, mussels clean water as they feed, filtering their food from the water column, and with it, sediment and other pollutants. North America is a global center of mussel diversity, holding about 300 of the world’s more than 900 mussel species, but 65% of North American freshwater mussel species are imperiled.
All three species proposed for listing prefer faster moving streams, and within those streams they prefer shallower, faster-flowing stretches with stable stream bottoms dominated by coarse sand, gravel and cobble. The Cumberland moccasinshell grows to about 2.5 inches long and lives 5-20 years, while the Tennessee clubshell and Tennessee pigtoe are larger, at around 3.5 inches long, and live 30-50 years.
The FWS consulted with species and habitat experts from state wildlife agencies and universities, and other researchers to compile and analyze all available data on the mussels and their well-being. The resulting species status assessment was then peer-reviewed.
Comments on the proposal will be accepted through 11:59 p.m. Saturday, Oct. 21. Submit comments online at regulations.gov by searching for docket number FWS-R4-ES-2023-0112. Any requests for a public hearing on the matter must be submitted in writing to U.S. Fish and Wildlife Service, 160 Zillicoa St., Asheville, NC 28801, also by Oct. 21.