UToledo Ecologists Lend Research Support to Sturgeon Reintroduction Efforts

UToledo Ecologists Lend Research Support to Sturgeon Reintroduction Efforts

An incidental catch of a lake sturgeon is rare.

But it's less of an angler's tall tale than it once was, thanks to a collaborative effort to bring this legendary species back to the waters where it once swam abundantly in the eastern and central United States and Canada.

The University of Toledo is a key collaborator in this effort in the Maumee River and western Lake Erie, with faculty and students lending research support to a multi-agency initiative to reestablish a self-sustaining population of lake sturgeon - hopefully - before 2040.

"Sturgeon are an iconic species of the Great Lakes," said Dr. William Hintz, an associate professor of ecology who leads this effort at UToledo. "The recreational and economic advantage is just one of the reasons we're making this effort to bring them back."

Lake sturgeon, easily recognizable by their torpedo-shaped bodies covered in bony plates called scutes, are a fascinating species that has changed very little since the days when they shared waters with prehistoric dinosaurs. Today, they're one of the largest and longest-lived fish species in the world, routinely reaching 4 to 6 feet and 50-plus years.

Once so plentiful that historical accounts described settlers crossing rivers on their backs, they've faced significant population declines due to habitat loss, overfishing and pollution since the 1800s, including extirpation from the Maumee River.

Enter the U.S. Fish and Wildlife Service, the U.S. Geological Survey, the Ohio Department of Natural Resources Division of Wildlife, the Toledo Zoo and Aquarium, Michigan State University and UToledo, which came together in an ambitious two-decade reintroduction plan beginning in 2018.

The collaborative effort has resulted in the release of annual cohorts of approximately 3,000 palm-sized juveniles, a subsample of which are equipped with acoustic transmitters that allow UToledo researchers to track their movements through receivers that are strategically positioned throughout the Maumee River and Lake Erie under the Great Lakes Acoustic Telemetry Observation System.

Their most recent analysis of this telemetry data is promising.

While it remains too early to declare success when dealing with a species that doesn't reach sexual maturity until 12 to 15, they calculated promising first-year survival rates for cohorts introduced in 2018, 2019 and 2021 as published in the peer-reviewed North American Journal of Fisheries Management.

"If they survive at this age, it's a really good sign," Hintz said. "Once they grow beyond the first-year stage, their survival rates are high. At that point, it becomes likely they will become adults and hopefully stick around and reproduce in the Maumee River."

The Maumee River initiative informs and supports more recent sturgeon reintroduction initiatives in other Lake Erie tributaries like the Cuyahoga River and Sandusky River, where the U.S. Fish and Wildlife Service and the Ohio Department of Natural Resources Division of Wildlife have released lake sturgeon.

Hintz is one of nine faculty ecologists affiliated with UToledo's Lake Erie Center, a research facility situated approximately 15 miles from Main Campus on the shores of western Lake Erie. Its researchers study algal blooms, invasive species, salt pollution and more, exploring the local environmental conditions for insights applicable throughout the Great Lakes and worldwide.

The Lake Erie Center also offers hands-on research opportunities to students ranging from first-semester undergraduates to ecology and organismal biology doctoral students like Mikayla Kindler. She began working as a research technician at the Lake Erie Center in 2023, leading crews in efforts to remove invasive grass carp from local waterways under the direction Bob Mapes in the laboratory of Dr. Christine Mayer, before enrolling as a graduate student with Hintz in 2024.

Today she primarily focuses on sturgeon.

"It's a lot of data analysis," she said. "I work on some of the modeling, trying to provide insights to the managers and other biologist so they have a better understanding of what the fish are doing, what factors are relevant to their survival and what steps we may be able to take as a collaborative team to help this reintroduction effort overall."

As a recreational angler since her childhood on Lake Michigan, Kindler can appreciate the economic benefits of returning sturgeon to the Great Lakes. For now, she can only imagine the excitement of catching a sturgeon - let alone one of the tagged specimens she's personally released as recently as this fall into Maumee River.

But it's their legacy that really excites her about her work.

"Sturgeon have been around for so long, and we're directly responsible for decreasing their population since the 1800s," she said. "I feel so honored that I get to be a part of this project to bring this icon back to the Great Lakes."