This ancient fish, once extinct in the Tennessee River system, has made a comeback thanks to a savvy reintroduction initiative by TVA and its partners.
TENNESSEE VALLEY-The lake sturgeon (Acipenser fulvescens) isn’t a handsome fish. It looks like what it is: primeval. Evolutionarily ancient, its body is comprised of bony plates, giving it a lumpy, bumpy appearance. As a bottom feeder, it sports a pointy nose with odd rubbery lips. And it can be both huge (growing up to six feet long and weighing upwards of 200 pounds) and old (living 60 years or more).
David C. Matthews
“They’re nothing you’d want to cuddle up to,” says TVA aquatic zoologist David C. Matthews. Still, he’s always glad to see them. “They’re a big, long-lived fish that’s a natural part of our eco-system. It’s a good thing that they’re here.”
That wasn’t always the case. Native to the Tennessee Valley, lake sturgeon became extinct in the region during the 1960s, partly due to overharvesting—the females were prized for their eggs, a.k.a. caviar.
“It’s a species that takes a long time to come to maturity for 10 or 12 years, and that doesn’t reproduce every year,” Matthews explains. “Overharvesting really affected them.”
TVA dams exacerbated the problem. “The river fragmentation at the time didn’t help,” he says. This interrupted the lake sturgeon’s natural migration patterns.
“There were a lot of reasons they declined and, unfortunately, disappeared.”
Change for the Better
In the 1990s, however, TVA began to change the way it operated its dams, coordinating releases so that the river acted more like a river rather than just focusing on each dam in isolation, according to Matthews.
Also, it undertook an initiative to improve oxygen content in the tailwaters. “When we draw water down now, the water has a good amount of oxygen thanks to the improvements TVA made,” Matthews explained. “We really looked to improving aquatic life downstream.”
Conditions were right for a reintroduction of the species. So TVA joined forces with partners such as the U.S. Fish and Wildlife Service, the Tennessee Wildlife Resources Agency, the Tennessee Aquarium, Tennessee Tech and other partners to form the Lake Sturgeon Working group and bring back the lake sturgeon. TVA is proud to support and partner with local, state and federal groups including the Tennessee Aquarium help raise the sturgeon released during the spring and fall events.
In the early 2000s, the partners began to restock the Tennessee River—a massive effort that to date has seen 170,000 juvenile lake sturgeon set free in the Tennessee, and an additional 23,000 in its tributary, the Cumberland River.
Some of the most visible parts of the effort are the sturgeon release events, which provide opportunities for the public to see these magnificent fish being released into the Tennessee River. These include the spring release at the Tennessee Aquarium in Chattanooga, and Sturgeon Fest, an autumn event invites Knox County school children to release the fish into the French Broad River (another Tennessee River tributary) at Seven Islands State Birding Park. Each fish is 4 to 6 inches in length—the size thought to be optimal for survival.
“It really is a big success,” says Aurora Pulliam, the TVA recreation agreements specialist who helps organize Sturgeon Fest. “The U.S. Fish and Wildlife Service brings the fish, and the kids will get them in hand and carry them to the water. There are all these aquatic and fisheries biologists at the event who will talk to the kids about anything. We see it as an opportunity to talk to the next generation of lifelong conservationists.”
Seeing Success
That’s important, as it will take many more years to ensure that the lake sturgeon population is well established and that the project is a successful one. So far, it looks good, says Matthews.
“We are starting to monitor now using baited trotlines,” Matthews explains. “We come in, collect them, weigh and measure them and put tags in them so that we know if we capture the same fish again.
“So far, we’re not seeing a lot of tagged fish, so that tells us that there are a lot of them out there. And we’re seeing a lot of age structure—different-sized fish—and that tells us they’re doing just fine. We saw one this year that was 50 inches long.”
It’s early yet, in the grand scheme of things, but hopes are high that the river-wide reintroduction will be successful. “This is a top-rated conservation initiative in the country right now, just because of the scope of it,” Matthews explains. “It’s one thing to reintroduce a fish on a creek level. We are stocking an entire river system. We’re seeing them from Knoxville to Guntersville. “
The lake sturgeon is a protected species; if you catch one, set it free. Then call the Tennessee Wildlife Resources Agency and let them know where and when you caught it. “We use that data,” Matthew explains. “They’ll even send you a little certificate that says you caught a lake sturgeon.”
You’ll have played your part in a very good thing. “From the 60,000-foot view, it’s amazing that with a little money and effort, we can bring a species back to its former home,” Matthews concludes. “It just takes a little help from humans.”
Media Release/TVA Newsroom
