Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for the Cumberland Elktoe, Oyster Mussel, Cumberlandian Combshell, Purple Bean, and Rough Rabbitsfoot

The Fish and Wildlife Service (Service) determines endangered status for five freshwater mussels--Cumberland elktoe (Alasmidonta atropurpurea), oyster mussel (Epioblasma capsaeformis), Cumberlandian combshell (Epioblasma brevidens), purple bean (Villosa perpurpurea), and rough rabbitsfoot (Quadrula cylindrica strigillata)--under the Endangered Species Act of 1973, as amended (Act). All five species have undergone significant reductions in range and numbers. They now exist as relatively small, isolated populations. The Cumberland elktoe exists in very localized portions of the Cumberland River system in Kentucky and Tennessee. The oyster mussel and Cumberlandian combshell persist at extremely low numbers in portions of the Cumberland and Tennessee river basins in Kentucky, Tennessee, and Virginia. The purple bean and rough rabbitsfoot currently survive in a few river reaches in the upper Tennessee River system in Tennessee and Virginia. These species were eliminated from much of their historic range by impoundments. Presently, these species and their habitats are being impacted by deteriorated water quality, primarily resulting from poor land-use practices. Because the species have such restricted ranges, they are vulnerable to toxic chemical spills.