ELECTROFISHING
State agencies shock North Chickamauga Creek to study environment, fish health
Jeff Simmons walks through North Chickamauga Creek in waders and boots; strapped to him is a backpack electrofisher. He looks more Ghostbuster than aquatic zoologist.
The Tennessee Valley Authority zoologist sends an electric current through the water with an electrode — a device that looks similar to a handheld metal detector — temporarily shocking nearby fish.
Simmons and a team of other aquatic conservationists work in groups to study the health of 700 sites in the Tennessee Valley.
“The overall purpose of what we’re doing is to rate stream water and the things that live in it,” Simmons said. “We figure out what is pristine, and what we find rates
against the pristine conditions to assess what’s going on. ”
The shock is similar to a less intense stun gun, he said. Simmons and other zoologists and biologists assure the public the process keeps the fish
alive and does no long-term damage to either the fish or the environment.
Two others, one with TVA and another with the Tennessee Wildlife Resources Agency, stand downstream with a seine — a long net that spans much of the creek — collecting anything that comes its way. Another TVA aquatic zoologist, David Matthews, stands near Simmons, collecting fish with a smaller net.
Simmons turns off the current, yells, “Clear!” and the two holding the larger net flip it over, capturing anything in its webbing.
They document and analyze each fish.
They are looking for things such as species richness, feeding group levels, tolerance levels, disease and other factors. They enter the data and get a number to determine the healthiness of the creek. The number lands between 12 and 60, with 60 being a perfect score.
“This is the basis for us to target our resources to try to make improvements in the protection of water quality and aquatic life in the stream,” TVA Water Resources Specialist Shannon O’Quinn said. “These critters are like the canary in the coal mine. If something starts happening
here, then we know that we need to be looking at how to fix those things.”
The entire process is called Index Biotic Integrity, known as an IBI.
Matthews, who has done this for 25 years, can count on two hands the number of perfect scores he’s seen.
TVA issues annual reports on the findings, and the wildlife resources agency documents the data, as well.
“We have long-term data that we can look at and track the health of this stream and the health of this fish population,” Jason Henegar, assistant chief of fisheries at TWRA, said. “We’ll use this data if we’re looking to change fishing regulations on smallmouth bass, for instance. So if we’re doing that, we can look at longterm data to see how the population has responded to that.”
One of the key purposes of the process is to track whether areas are getting better, worse or staying stable.
“Surprisingly, about 70 percent of the sites we do in the valley are pretty stable,” Matthews said. “Now, that may be stable poor or stable good.”
In areas getting worse, TVA will partner with other groups to help revitalize areas, Simmons said.
The agency hosted a meeting Tuesday and will again today with some of those groups.
The meeting, the third annual Tennessee River Biodiversity Network Meeting at the Tennessee Aquarium, brings together conservationists, biologists, environmental leaders and others to celebrate the area’s aquatic life while discussing ways to protect and improve it.
A recent study by TVA and the University of Tennessee found the annual value of recreation on the Tennessee River reservoir is nearly $12 billion.
The valley also has the most diversity of aquatic species in North America, Simmons and O’Quinn said, adding that the water is important to farmers, industries, native species, the general public and those who use it recreationally and contribute to the economic impact.
“This gives us a way to identify whether there are water quality problems,” O’Quinn said. “And then we can go out and work with partners to try to fix those problems.”
TVA and the TWRA will use the data collected this week to determine how to properly protect and preserve water in North Chickamauga Creek.
Then, it’s on to the next one.