SPECIES
DIVERSITY
The Coosa Watershed is the largest and most biodiverse subwatershed of the
Mobile River Basin in terms of overall number of fish, mussel and snail
species. Historically the basin harbored 147 fish species, and 78 taxa of
snail (60 species endemic to the Coosa). (State of Rivers)
Aquatic biodiversity has
declined significantly as a result of riverine habitat loss, modification
and fragmentation from impoundments, and water quality degradation. The
remaining significant reaches of free-flowing riverine habitat on the
mainstem Coosa River are limited to
1) An
8-mile reach downstream from Jordan Dam. This reach is affected by
flucuating releases from Bouldin and Jordan dams and provides habitat for
the endangered Tulotoma snail and the threatened fine-lined pocketbook. The
shoal lily occurs occasionally on shoals in this reach. Paddlefish, a
species of concern, is restricted to downstream of the Fall Line. (Corps)
2) A
21-mile reach of bypassed river channel extends downstream from Weiss Dam,
and is known as the Dead River.
3) A
9-mile free-flowing reach extends downstream from Rome, GA to the headwaters
of Weiss Lake. There is a fish consumption advisory for this section of
river due to elevated PCB levels. Few mussel species persist in this reach.
Due to
the construction of dams and limited free-flowing mainstem habitat, much of
the remaining faunal diversity in the Coosa Basin is restricted to
tributaries of the Coosa. (State of
Rivers)
The upper Coosa supports
the largest number of Federally listed species (6 fish and 7 mussels)
compared to the lower Coosa system (2 fish and 4 mussels). Many of these
species occur in the Conasauga, upper Etowah, and Coosawattee River systems,
which contain the longest remaining reaches of free-flowing river in the
Coosa Basin. (Corps)
FISH
Fish diversity in the
Coosa Basin is extremely rich, ranking it ___ out of ____ total watersheds
in Alabama. A total of 147 fish species have been documented from the Coosa
River drainage. (Corps)
At this time 7 fish known
from the Coosa drainage are listed as federally threatened or endangered.
Only two of these occur in the Alabama portion of the basin.
The Blue shiner (Cyprinella
caerulea), a threatened species, is found only in the upper
Coosa River drainage in Georgia, and in Alabama in a 5.2 mile segment of the
Little River, 18.4 mile segment of Choccolocco Creek / Calhoun Co., and a
22.4 segment of Weogufka Creek / Coosa Co. (Pierson, 1998) This
shiner inhabits small to medium streams over rocky substrate with moderate
to slow current. (Recently a new population of this shiner was found in
Spring Creek which drains to Weiss Lake. This population is disconnected
from the Little River population by an inundated section of Weiss Lake
(Blanchard 2001).
The Pygmy sculpin (Cottus
pygmaeus), a threatened species, is known only in Alabama at
Coldwater Spring near Anniston, and its spring run to its confluence with
Dry Creek in Calhoun County. (Corps) This fish is a mottled and
banded bottom-dwelling species. Its colors allow it to blend perfectly with
the gravel on the bottom of the spring. (Godwin)
The five remaining
threatened and endangered species are found only in the Georgia portions of
the Coosa watershed, or in other subwatersheds of the Mobile River Basin.
The Etowah darter (Etheostoma
etowahae) is a federally listed endangered species that
requires riverine or tributary watercourses with riffles and moderate to
strong current. It is found only in the upper Etowah River system above Lake
Allatoona in GA. (Corps)
The Cherokee darter (Etheostoma
scotti), a threatened species, is present in the upper Coosa
River system in GA. It is found in small to medium sized streams with gravel
and cobble substrates. (Corps)
The Amber darter (Percina
antesella) is an endangered species with designated critical
habitat on the Conasauga River in Tennessee and in Murray and Whitfield
Counties, Georgia. This darter is found in mainstream river and large
tributary habitat with moderate to swift currents. (Corps)
The Goldline darter (Percina
aurolineata) , a threatened species, is presently found only in
the Coosawattee River in Georgia and the Cahaba River. This darter inhabits
rivers and large tributaries having swift current over gravel, cobble,
bedrock, and boulder substrate. (Corps)
The Conasauga logperch
(Percina jenkinsi), an endangered species, has designated
critical habitat on the Conasauga River from Polk County, Tennessee,
downstream to Murray County, Georgia. It is found only in 148 feet reach of
the river, in association with riffles and runs of moderately deep water
with swift current over coarse substrates. (Corps)
Many biologists and
conservation agencies also evaluate fish species of concern that are showing
signs of being at risk of extinction. According to ___________, there are
___ of these at-risk species in the Coosa Basin.
The
Holiday
Darter (Etheostoma brevirostrum)
has the most distinctive coloration of all darters found in the subgenus
Ulocentra. This species is only found in the Coosa River
drainage where it prefers medium to large streams with fast current and a
mixture of substrate including sand, gravel, small boulders, and river weed.
Most populations, although disjunct are stable. This species is common in
the Upper Conasauga River drainage that drains portions of the Cherokee and Chattahoochee
National Forests in Georgia.
Fish status in Coosa Basin
Total species
# endemic
# extinct
# extirpated
# threatened or endangered 7
# imperiled
# special concern
MUSSELS
There are 10 threatened
and endangered mussels from the Coosa.
The Upland combshell (Epioblasma
metastriata), an endangered species, is found in a small
portion of the Conasauga River in Georgia and may be present in upper
reaches of the Black Warrior and Cahaba River drainages in Alabama. Suitable
habitat for this mussel is free-flowing rivers and large creeks with gravel
and sandy gravel substrates.
The Southern
acornshell (Epioblasma othcaloogensis) is an endangered mussel
found in large creeks and small rivers with rock and gravel substrate. This
species has been found in the Coosa River drainage of Georgia and the Cahaba
River drainage of Alabama above the Fall Line.
The Fine-lined
pocketbook (Lampsilis altilis) is a threatened species found in
the Coosa River and Talladega Creek systems in Alabama and the Etowah and
Conasauga Rivers in Georgia. Preferred habitat is free flowing rivers and
creeks with gravel and sandy gravel substrate.
The Alabama
moccasinshell (Medionidus acutissimus), a threatened species, is
found in the upper Coosa River drainage of northwest Georgia. It occurs in
rivers and large creeks where substrates are boulders, cobbles, gravel and
sand.
The Coosa
moccasinshell (Medionidus parvulus) mussel is endangered and is
found in the Coosa River drainage of northeast Alabama and northwest GA
where it occurs in association with free-flowing water over gravel and
sandy-gravel substrates.
The Southern clubshell
(Pleurobema decisum) is an endangered mussel found in scattered
populations in the Coosa and Cahaba River systems and in the Coastal Plain
tributaries of the Tallapoosa River. Preferred habitat is medium sized
rivers with moderately high gradient and stable sand-gravel substrate.
(Corps)
The Southern pigtoe
mussel (Pleurobema georgianum), an endangered species,
historically was found in the upper Coosa River drainage in GA, AL and TN,
including Chattooga, Coosawatee, and Conasauga Rivers. Most recent records
of the southern pigtoe are from the Conasauga above Dalton.
The Triangular
kidneyshell (Ptychobranchus greeni) is an endangered species that
occurs in the Coosa River drainage of north GA and the Cahaba River.
Mussel status in Coosa Basin
Total species
# endemic
# extinct
# extirpated
# threatened or endangered 10
# imperiled
# special concern
SNAILS
Recent surveys of aquatic
gastropods in the Coosa basin have been described by scientists as
“disturbing.” In ’92 Pierson and Bogan failed to find 29 species known to
occur historically in the watershed.
Currently only 3 species
of snail are listed as threatened or endangered. All are found only in the
Alabama portions of the Coosa Basin.
The Lacy elimia (Elimia
crenatella) is a threatened species found only in Cheaha
(largest population), Emauhee, and Weewoka creeks in Talladega County. It is
presumed extirpated from its former habitats of the Coosa mainstem, Big
Will’s Creek, Kelley's Creek, and Choccolocco and Tallaseehatchee creeks.
(Pierson and Bogan)(Federal Register)
The Painted rocksnail
(Leptoxis taeniata) is a threatened species found
in only three tributaries of the Coosa Basin; the lower reaches of
Choccolocco Creek (Talladega County), Buxahatchee Creek (Shelby County), and
Ohatchee Creek (Calhoun County). The painted rocksnail has apparently been
extirpated from the Coosa mainstem, as well as the Alabama and Cahaba
rivers. (Federal Register)
Snail status in Coosa Basin
Total species
# endemic
# extinct 23
# extirpated
# threatened or endangered 3
# imperiled
# special concern
There are 23 species of
snail that are presumed to be extinct in the Coosa. (Corps)
The Cylindrical lioplax (Lioplax
cyclostomaformis) was once known from the Coosa mainstem in Shelby and
Elmore counties as well as the tributaries of Little Wills Creek (Etowah
county), Choccolocco Creek (Talladega county), and Yellowleaf Creek (Shelby
County). Currently found only in the Cahaba basin. (Federal Register)
The Flat pebblesnail (Lepyrium
showalteri) was once known from the Coosa mainstem in Shelby and Talladega
counties. It has been missing from this habitat since the construction of
Lay and Logan Martin Dams. Currently found only in the Cahaba basin.
(Federal Register)
The Round rocksnail (Leptoxis
ampla) was once known form the Coosa mainstem in Elmore county as well as
the tributaries of Canoe Creek and Kelly’s Creek (St. Clair county),
Ohatchee Creek (Calhoun county), Yellowleaf Creek (Shelby County), and
Waxahatchee Creek (Shelby and Chilton counties). It is currently isolated to
the Cahaba River basin. (Federal Register)
PLANTS / OTHER
There are two aquatic
dependent plants that are protected by the endangered species act.
Kral’s water plaintain
is a threatened species of perennial aquatic herb that grows in
riverine habitat, on exposed shoals, or in sand, gravel and silt in quiet
pools up to 3 feet in depth. (Corps) It’s only remaining habitat is
approximately 12 sites in the Little River drainage area in Georgia and
Alabama stretching about 25 river miles.
