New partnership hopes to restore this ‘species of special concern’ to the St. Louis River

DULUTH – More than a century has passed since the St. Louis River teemed with lake sturgeon, the largest of all Great Lakes fish and as ancient as dinosaurs.

Aided by polluted and dam-blocked spawning grounds while industry mushroomed in a young Duluth, overfishing and logging wiped out the native species.

For more than 40 years now, tribal, state and federal efforts to stock the migratory fish in the river have been underway, but the local population of what Minnesota considers a “species of special concern” remains below management goals.

A new partnership between the Great Lakes Aquarium, Fond du Lac Band of Lake Superior Chippewa, the Department of Natural Resources and the U.S. Fish and Wildlife Service aims to bolster the number of mature sturgeon living in Lake Superior and the river estuary by rearing them in their very waters.

The aquarium is seeking about $1 million from the state and federal government for a program that would allow the fish to “imprint” on St. Louis River water, in hopes they return to the river to spawn.

“There are local cues in the water” including pheromones, said Dan Wilfond, the DNR’s Duluth area fisheries supervisor.

“They can lead these fish back to their natal [birth] waters,” he said, which is particularly important for lake sturgeon because they don’t spawn until they are 15-25 years old, and don’t spawn every year.

Right now, both the DNR and the Fond du Lac Band stock and track lake sturgeon that have been reared at the Genoa National Fish Hatchery in Wisconsin or in a hatchery trailer along Michigan’s Ontonagon River. There is some evidence that St. Louis River-stocked sturgeon try to return to those waters to spawn.

Efforts to restore lake sturgeon throughout the Great Lakes, which are well below historic levels, have been ongoing for decades. In Lake Michigan, for example, the population is 1% of what it was historically.

The Great Lakes Aquarium hopes to buy a hatchery trailer fitted with tanks and filled with filtered river water to raise 3,500 fish. Once they are ready to be released, the DNR will stock 2,000 in the lower half of the river, and the Fond du Lac Band will stock 1,500 in the 200 miles of the upper estuary. The numbers sound large, but some of the youngest sturgeon (fry) that are stocked float downstream, and quite often become lunch for other fish or wildlife. The aquarium also plans to build an exhibit that would showcase 100 fish for a year, allowing them to grow, educate visitors and then be released into the river at a larger size, ensuring a higher rate of survival.

At the aquarium, “we talk about what other people are doing for conservation, and I think we are doing a really great job of teaching the 220,000 people that come through,” said Jay Walker, its executive director. “This gives us an opportunity to actually be part of the work.”

The sturgeon at the aquarium have thrilled kids for years with their looks and personalities. Several swim in a touch pool where they regularly poke their snouts out of the water at curious visitors.

“They are an extremely chill fish,” said Miranda Rinne, aquatics curator at the aquarium.

The prehistoric bottom-feeding fish can grow to 7 feet long and live to be more than 100 years old. They have distinctive barbels that stem from their snout that help them find food.

Last year was productive for the Fond du Lac Band, which stocked 5,000 fry and 1,750 advanced fingerlings (about 7 inches long), said Eric Torvinen, who works in the band’s fisheries department of its resource management division.

Stocking fish from Wisconsin and Michigan will continue even if the aquarium’s rearing program comes to fruition. Together, partners hope to bring lake sturgeon in Duluth back to self-sustaining levels, eventually allowing them to be harvested.

The upper estuary has “immeasurable habitat” for spawning, Torvinen said, and it’s easy to see how sturgeon were a major food source for the Anishinaabe when they settled here centuries ago.

Historically, they, along with walleye and whitefish, made up the most critical St. Louis River harvests for band members who lived along the river.

On a philosophical scale, lake sturgeon are considered the king of fish in Ojibwe culture and mythology, and as with other beings, are seen as relatives that need protection, said Thomas Howes, program manager of the band’s natural resources department.

The lake sturgeon is also a clan animal, meaning there are families who derive their identity from the fish.

“Because they’re struggling, we have a duty and a responsibility as a relative to do everything we can to enhance their life,” he said, and restore them to where they once thrived.