Today we started our weekend trip by conducting a freshwater mussel survey at Horton Ford in Hancock County, TN. We did a quantitative survey of the reach using quadrats and a systematic sampling method. This is part of Hua Dan’s PhD graduate research project. We are taking data to look at the population dynamics of this site, evaluate the success of introducing lab-propagated juveniles (mark-recapture), and to compare Horton Ford’s data to two other sites in which lab juveniles were released (Fugate Ford and Davis Property). In addition to the quantitative survey, we took several habitat measurements. We measured the flow across the left ascending channel, collected water samples (for later analysis in the lab, organic matter, chlorophyll, etc) and water quality data (pH, temperature, D.O., conductivity).
This site is part of the Clinch River. Upstream of the survey reach is a bridge and the road follows along both sides of the river. The river is separated into two channels by an island (containing various vegetation, trees, debris, substrate, shells etc). Our study reach runs along the left ascending channel. The first picture here is of us snorkeling for freshwater mussels. The vegetation in the background you see is the island that separates the two channels. Much of the bank along both channels is degraded by the presence of cows that are allowed to roam free through the area…as you can see in the background of the second picture-one deciding to cross right through our study site…
Even though the cattle may be destructing the banks, and occasionally trampling a mussel or two, this is a great site for freshwater mussels (not saying that it wouldn't be without the cattle too). Some of the more common species we found today include the pheasantshell, Cumberland moccasianshell, and the rainbow mussel. Some of the less common to rare ones include the Cumberland combshell, the shiny pigtoe and the cracking pearlymussel. The first mussel pictured here is a pocketbook (Lampsilis ovata) that was lab-propagated and released into a cage at this site in order to determine growth. The last picture is of a young Appalachian elktoe, which is endangered and not a common find.
Now off to the hotel and round 2 tomorrow at Fugate Ford--the Powell River....
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