Winter Monitoring Program Tracks a Jurassic Giant

Waves lapped the aluminum boat broadside, echoing through the frigid morning.

David Matthews, Tennessee Valley Authority aquatic zoologist, eased the boat toward the white buoy bobbing in the Clinch River.

This was the first lake sturgeon monitoring site of the day, and part of the annual, multi-agency lake sturgeon reintroduction program stretching back to the early 2000s.

Overfishing and habitat changes led to the disappearance of lake sturgeon from the Tennessee River system in the 1960s.

Since annual releases began, the prehistoric fish glide once again above river bottoms in the coldest murk. They swim along hundreds of miles of river that can be over 100 feet deep, making it tough to predict exactly where they’ll be from one day to the next.

That unpredictability is what makes the sturgeon monitoring program a challenge.

But it’s also what makes it exciting.

At the helm of the boat, Matthews squinted up the steely river.

“We’re dealing with a prehistoric fish that swims and eats, with a brain the size of a walnut,” Matthews said. “How do you figure out what they do?”

TVA aquatic zoologist Dave Matthews maneuvers a boat so he and his team can place trot lines for the next day’s monitoring.  

The Science of Sampling

Even if the fish aren’t predictable, the routine to sample them is a well-oiled machine.

It’s the same routine that fellow TVA fisheries staff Lyn Williams, Aaron Coons and Justin Wolbert used during their shifts searching for sturgeon, too.

“Who wants to learn how to pull?” Matthews asked his two-man crew at the first site.

Pulling meant bringing in trot lines – 250 feet of fine-braided rope with 50 hooks baited with chunks of carp – that the teams had sunk a day prior in wind so strong it frothed the river into whitecaps.

Jonah Henry, Tennessee Wildlife Resources Agency wildlife technician, waved a gloved hand and stepped forward.

Any one of the hooks pulled in from the depths might hold a writhing lake sturgeon. The fish that TVA biologists and their partners released as 6-inch babies in summers past can grow to 200 pounds and 6 feet long.

Crews slide the fish into a huge, oxygenated tank. Then they record the distinctive pattern of the sturgeon’s sharp scutes – plates that cover their bodies instead of scales – and tag each fish with a tiny electronic chip like pet dogs and cats have.

Data collected year after year helps biologists answer key questions – where sturgeon live, how fast they grow, when they breed, how healthy they are and how far they travel.

And, critically, just how many fish might be out there.

It’s a question with an answer decades in the making.

Because the monitoring program is long-term, biologists like Matthews must teach new generations the secrets to success.

“When you get to the hook, you lay it down,” Matthews said, showing Henry how the hook fit into a slot in a specially made, square wooden box resembling a breadbasket.

“There’s a little hole, right here.” He pointed. “You don’t want to ever get them out of order.”

Henry turned the hooks and Luke Troha, U.S. Fish and Wildlife Service biological technician, leaned over the water, gloved hands reeling in the trot line. Matthews looked on in approval as Henry settled each hook into its slot.

“It’s a beautiful thing when it works right,” Matthews said. “You got it?”

Henry nodded as Troha slid him more line, their pace already increasing.

“I know you do,” Matthews said.

After pulling in active lines with his crew, Dave Matthews spears fish chunks to set up a new trot-line box.  

'Let’s Make it Happen’

The program to bring back lake sturgeon began as just an idea.

Matthews was talking to his supervisor, retired TVA biologist Charlie Saylor, back in the early 1990s.

“I was spawning paddlefish and walleye … to go into the Cherokee Reservoir,” Matthews said. “And Charlie said, ‘Boy, it sure would be nice if we had sturgeon back in the Valley."

It would be nice, Matthews thought.

And the waters were ready.

TVA’s Reservoir Release Improvement Program, which began in the 1990s, changed the way TVA operated its dams.

That, in turn, improved oxygen levels and water flow.

“Let’s give it a shot,” Matthews told Saylor all those years ago. “Let’s make it happen.”

Matthews offered to call the Wild Rose Hatchery in Wisconsin, the only one in the country rearing lake sturgeon at the time.

“This is the story no one ever hears about sturgeon,” Matthews said. “I got on the phone. I was naive enough to think I could just call up and get some eggs.”

He chuckled. “And it happened.”

The hatchery sent 50,000 sturgeon eggs, shipping them to Tennessee for free. TVA and the Tennessee Wildlife Resources Agency stocked them above the Norris Reservoir on the Clinch River in 1993.

“All of a sudden, we were in the sturgeon business,” Matthews said.

TVA fisheries biologist Justin Wolbert holds a lake sturgeon his team hooked during multi-agency efforts to monitor sturgeon in TVA’s reservoir system.  

Growing Partnerships

But they weren’t in the business quite yet.

For long-term success, a full sturgeon reintroduction program would need more partners.

Hatcheries to nurture eggs. Biologists with specialized tanks to transport and release young into the water at multiple sites each year. Environmental educators to teach the public about the return of these river giants. And many agencies committing to cold days of scanning the extensive river system alongside TVA, for years to come.

So Matthews and Saylor waited.

“By the mid-1990s, the Tennessee Aquarium reached out,” Matthews said. “And we got a call. ‘We’re looking for a long-term conservation program,’ they said.

“Charlie said, ‘Boy, do we have one.’”

The Tennessee Aquarium joined TVA, the Tennessee Wildlife Resources Agency and many other state and federal agencies to form the group that became the Southeastern Lake Sturgeon Working Group, which TVA and others continue to be part of today.

“We’ve got all these partners now,” Matthews said. “It’s the only way a project of this size is going to work.”

Today, the U.S. Fish and Wildlife Service – including its Warm Springs National Fish Hatchery, where most of the sturgeon that TVA releases are born – and the Tennessee Wildlife Resources Agency, Georgia Department of Natural Resources, Kentucky Department of Wildlife and Natural Resources, University of Tennessee and Tennessee Tech all contribute staff, boats, research and time to the effort.

And the public contributes, too, releasing thousands of baby sturgeon at annual public celebrations such as Sturgeonfest.

“We can’t do it by ourselves,” Matthews said.

Tennessee Wildlife Resources Agency wildlife technician Jonah Henry and U.S. Fish and Wildlife Service biological technician Luke Troha are hands off as a weighted trot line unreels.  

Catch of the Day

While Troha and Henry pulled in croaking catfish – some glistening blue in welcome sunshine – no sturgeon appeared at the site on their recent outing.

Yet this year’s monitoring brought in a record number of sturgeon, at record sizes.

Jason Henegar, Tennessee Wildlife Resources Agency assistant chief of fisheries, and his crew pulled in two sturgeon, ages 9 and 10, just downriver on the Clinch.

The week before, on mornings dipping into the 20s, Matthews and his crew caught an 18-year-old giant sturgeon on the Cumberland River.

And biologists caught the largest lake sturgeon ever captured during monitoring – a 60-inch, 63-pound fish.

Crews keep meticulous records of the fish they catch and the locations they sample each season. Every fifth year or so, they sample downriver as far as Nickajack Reservoir near Chattanooga.

Since 2011, they have caught and released 820 sturgeon.

“We’re seeing all age classes,” Matthews said.

And they’re seeing more sturgeon each year.

Jonah Henry, a Tennessee Wildlife Resources Agency wildlife technician, stands ready to pull in equipment at a lake sturgeon monitoring site.  

A Helping Hand

This year, TVA crews and their partners caught 87 sturgeon.

More of these massive fish are swimming in the region's waters. And that means the program is working.

“We are at an exciting time in the lake sturgeon reintroduction project,” Brandon Simcox, river and streams coordinator at Tennessee Wildlife Resources Agency, said.

In fact, 2023 and beyond are long-awaited years.

“Lake sturgeon take about 20 years to become mature,” Simcox said. “So in the near future, we could potentially see the first evidence of spawning in Tennessee in over half a century.”

At the end of their workday, Matthews piloted his boat upriver to let Troha and Henry unreel trot lines at eight new sites.

The river glinted silver in late-afternoon light.

“It feels good … to know I’ve had a hand in getting these fish back here,” Matthews said.

“I just keep thinking about that first conversation. ‘Wouldn’t it be nice?’ That’s how it starts. Wouldn’t it be nice to have these fish back here? They’re supposed to be here.”

Photo Gallery

Chunks of hooked fish are fixed to a trot line, ready to be cast into the water to catch lake sturgeon.

TVA aquatic zoologist Aaron Coons, a member of the lake sturgeon monitoring team, holds a lake sturgeon during a recent outing.

Because catfish species share reservoir habitat with sturgeon, biologists often catch and release them.

Luke Troha and Jonah Henry prepare to reel in a weighted trot line that sits on the reservoir bottom.

After reeling in lines and setting new boxes, the crew sets floating TVA buoys for the next day’s monitoring.

Biologists use this specially designed box for trot lines and baited hooks.