The Tennessee Aquarium’s longest-running conservation program is celebrating major developments that have biologists and wildlife managers brimming with excitement.
This week, the Aquarium honored the 25th anniversary of the first Lake Sturgeon release in 2000 with a public event on the northern shore of the Tennessee River in downtown Chattanooga.
There, about 500 juvenile Lake Sturgeon measuring 6 to 12 inches long were ferried to the water’s edge in clear plastic buckets and released into the river by a group of invited officials, community leaders and other special guests, including 46 students from Hixson High School.
Massive, ancient and long-lived, the Lake Sturgeon has been extirpated (locally extinct) in Tennessee since the 1970s. The effort to re-establish this state-imperiled species began in 1998 with the formation of the Southeast Lake Sturgeon Working Group, a collaborative partnership between non-profits like the Aquarium as well as universities and state and federal agencies.
Since the start of reintroductions in 2000, working group members have raised and released more than 430,000 Lake Sturgeon into the Tennessee and Cumberland river watersheds.
The cumulative effect of that work is already changing the Lake Sturgeon’s fortunes. This year, the species’ conservation status in Tennessee decreased from endangered to threatened, an adjustment that reflects the long-term impact of the restoration program, says Dr. Anna George, the Aquarium’s vice president of conservation science and education.
“I’m positive the downgrading is a result of the Southeast Lake Sturgeon Working Group’s effort,” she says.
After a quarter-century of stocking, the reintroduced population of Lake Sturgeon is now large enough, mature enough and genetically robust enough that wild spawning could begin at any time. In fact, wildlife managers say, it may already be taking place.
“We're seeing sexually mature fish now,” says Brandon Simcox, the rivers and streams coordinator at the Tennessee Wildlife Resources Agency, which is also a member of the Southeast Lake Sturgeon Working Group.
“We have the recipe there that we should start to see natural reproduction.”
At 652 miles long, the Tennessee River is the largest tributary of the Ohio River, which is itself the largest tributary of the Mississippi River. According to data from the U.S. Geological Survey, its outflow is the seventh highest of any waterway in the United States.
Because of the size of the river systems through which the sturgeon are moving, it’s likely that they’re already spawning without anyone around to verify it yet, Dr. George says.
“I'm optimistic that it's probably happening and we just haven't detected it,” she says. “I am so motivated to get out there.”
Raising new generations of sturgeon is an involved process that begins each spring when biologists and wildlife managers collect eggs from wild spawning Lake Sturgeon in Wisconsin’s Wolf River, where the species’ population numbers remain healthy.
Once hatched, the young sturgeon are sent from federal hatcheries to partnering propagation facilities such as the Tennessee Aquarium Conservation Institute’s freshwater field station downstream from downtown Chattanooga. There, they spend months in the care of reintroduction biologists, eating near constantly until they’re large and robust enough to be returned to their ancestral waters.
Events like today’s release offer an opportunity for the public to personally contribute to the restoration of a species that has — in many cases — been missing from Tennessee since before they were born.
“Sturgeon releases are really, really exciting days,” Dr. George says. “One of the joys of working at the Tennessee Aquarium is we get to invite a lot of the public to come with us.”
Once the reintroduced population of Lake Sturgeon is confirmed to be self-sustaining, it will mark an important moment, not only for Lake Sturgeon but for all imperiled species in the underwater rainforest of Southern Appalachia.
“When that happens and we have an appropriately managed recreational fishery, we’ll have this recipe for success that we can apply to other animals that we might have lost through carelessness,” Dr. George says. “That's what's really so great to me about the Lake Sturgeon.
“It's not just about the fish; it's about everything.”
To view a live feed of Lake Sturgeon at the Tennessee Aquarium, visit tnaqua.org/livestream/lake-sturgeon-cam/
For additional insights into the history of the Lake Sturgeon restoration effort, listen to the latest episode of the Tennessee Aquarium’s official podcast, The Podcast Aquatic, at tnaqua.org/podcast/