SPECIES DIVERSITY

The Nature Conservancy considers the Tennessee Basin as a whole to be the single most biologically diverse river system for aquatic organisms in the United States. It also harbors the highest number of imperiled species of any large basin in North America with 57 fish species and 47 mussel species considered to be “at-risk.” (State of the Rivers) (Masters et al. 1998)

In Alabama, the section of the Tennessee Basin flowing into Wheeler Lake is the most threatened biologically with 23 “at risk” fish and mussel species. Of these 23, nine are federally listed as threatened or endangered. The Pickwick / Wilson Lake watershed is also significant with 15 “at risk” fish and mussel species (four of these are federally listed as threatened or endangered).

FISH
176 species of fish are known from the Alabama portions of the Tennessee River Basin. Two of these are believed to be extinct, the harelip sucker (Lagochila lacera) and the whiteline topminnow (Fundulus albollineatus). (State of the Rivers)

High species diversity occurs most prevalently in the free-flowing tributaries of the Paint Rock River (with 98 species) and the Flint River (with 83 species). The main channel of the Tennessee yields a lower diversity due to the impacts from dam construction and maintenance dredging (with 53 species). Other smaller watersheds of interest include Crow Creek (with 56 species), Big Spring-Browns Creek (with 35 species), and Dry Creek (with 32 species).

The Alabama cavefish (Speoplatyihimus poulsoni), an endangered species, is a small, white, and blind fish that exists in only one location; Key Cave in Lauderdale County, Alabama. At one time it may have been present in other caves west of Key Cave, but these caves are now inundated by Pickwick Lake. The Alabama cavefish is considered to be the rarest of all American cavefish, and one of the rarest freshwater fish in the world. The total population of this fish is estimated to be fewer than 100 individuals, with no more than 10 ever observed in a single visit. This fish is threatened by pollutants placed on row crop lands within Key caves recharge area, as well as by competition with the southern cavefish and predation from the Cave crayfish. (See Key Cave National Wildlife Refuge for more information) (US FWS Species Account)

The Boulder darter (Etheostoma wapiti), an endangered species, is found in Shoal Creek and the Elk River.         

The Palezone shiner (Notropis albizonatus), an endangered species, is found in the Paint Rock River

The Slackwater darter (Etheostoma boschungi), a threatened species, is found in Swan Creek, Cypress Creek, and the Flint River. It has critical habitat in

The Snail darter (Percina tanasi), an endangered species, is found in the Paint Rock River. 

The Spotfin chub (Cyprinella monacha), an endangered species, is found in Little Bear Creek and Shoal Creek.

The Tuscumbia darter (Etheostoma tuscumbia)

MUSSELS
In the Guntersville Lake section of the Tennessee 14 species of mussel are considered threatened or endangered by the Alabama Department of Conservation and Natural Resources. Of these only 6 are federally protected and one is being considered as a candidate species. 

Mussel species presumed to be extirpated from the Alabama portions of the Tennessee Basin include: 

The Oyster mussel (Epioblasma capsaeformis), a federally endangered species, lost its historic habitat within Alabama with the impoundment of the Tennessee River by the Tennessee Valley Authority between the years of ____ to _____. This species still maintains very small populations in the tributaries of the Tennessee and Cumberland River basins in Kentucky, Virginia, and Tennessee. (Federal Register)

The Cumberlandian combshell (Epiblasma brevidans), a federally endangered species, once found in the Alabama portion of the Tennessee Basin, has been extirpated with the advent of locks and dams altering its former habitat. Small populations of this species persist in the Cumberland and Tennessee River basins in Kentucky, Viginia, and Tennessee. (Federal Register)

Cumberland monkeyface (Quadrula intermedia), an endangered species once known from the Guntersville Lake section of the Tennessee Basin

Dromedary pearlymussel (Dromus dromas), an endangered species once known from the Guntersville Lake section of the Tennessee Basin

Orange-foot pimpleback (Plethobasus cooperianus), an endangered species once known from the Guntersville Lake section of the Tennessee Basin

Pink mucket (Lampsilis ovata), an endangered species once known from the Guntersville Lake section of the Tennessee Basin

Ring Pink mussel (Obobvaria retusa), an endangered species once known from the Guntersville Lake section of the Tennessee Basin

Rough pigtoe (Pleurobema plenum), an endangered species once known from the Guntersville Lake section of the Tennessee Basin

Candidate for listing

Slabside pearlymussel (Lexingtonia dollabelloides), is currently considered endangered within Alabama and is being considered for federal listing.

SNAILS 

In the Guntersville Lake Section, 3 species of snail are listed as threatened or endangered by the state. One other is listed as endangered federally.

The Tennessee Basin in Alabama is home to one endangered snail species.

Anthony’s riversnail (Athearnia anthonyi) is an endangered species known to exist in only two locations, the Sequatchie River in Tennessee and in Limestone Creek in Limestone County, Alabama. It is relatively large in comparison to other aquatic snails (measuring 1 inch in length) and primarily inhabits the shoal areas of large rivers. Most of its historic range has been altered by impoundments. (Fed Register)

The Spiny riversnail is believed to be extirpated from the Tennessee Basin in Alabama. (TVA-Guntersville)

PLANTS 
The Guntersville Reservoir Section of the Tennessee Basin provides habitat for eight federally listed, 43 Tennessee state-listed and 66 Alabama state-listed plant species known from DeKalb, Madison, Marshall and Jackson Counties in Alabama and Marion County in Tennessee. The federally listed species included: 

American Hart’s tongue fern, threatened

Arrowhead, threatened

Eggert sunflower, threatened

Price potato-bean, threatened

Green pitcher plant, endangered

Harperella, endangered

Morefield’s leather flower, endangered

Mountain skullcap, endangered

None of these federally listed plants occur on TVA lands within the Basin.

OTHER
Four terrestrial species are listed as federally threatened or endangered. They are:

The bald eagle (threatened), red-cockaded woodpecker (endangered), gray bat and Indiana bat (both endangered). 

The state’s largest populations of nesting Bald Eagle’s and gray bats occur in the Tennessee River Basin.

Two caves in the Guntersville Lake region, Sauta Cave (formerly Blowing Wind Cave) and Hambrick Cave both have populations of gray bats presumed to exceed 100,000 individuals during the summer months. Numerous other caves had smaller populations. Gray bats can feed up to 32 kilometers from their primary roosting site and depend heavily on emerging aquatic insects for their food supply. (TVA-Guntersville)