In 2013, the US Fish and Wildlife Service was examining a list of nine species to see if they should be added to the protected list. These included bridled darter, Panama City crayfish, Suwanee moccasin shell mussel, eastern hellbender salamander, Florida Keys mole skink, MacGillivray's seaside sparrow, boreal toad, Sierra Nevada red fox, and the Bicknell's thrush.