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A Living Fossil: The return of the sturgeon to Lake Erie and Ohio’s rivers; KSU News Lab; April 26, 2023

By Ben Weaver

A prehistoric fish is returning to Lake Erie, thanks to some new friends.

The sturgeon is a fish that scientists believe has remained relatively the same for the last 200 million years. That means it was swimming in North America’s waters long before even the T-Rex showed up 65 million years ago.

One of the most interesting features of the sturgeon is just how ancient it looks, said John Navarro, the Aquatic Stewardship Program administrator for the Ohio Department of Natural Resources Division of Wildlife. The fish lacks scales and is mostly smooth, with armor lining its back called scutes that look like the scales of an alligator. Sturgeon are long lived, with some reported between 110 and 152 years old.

“It’s a very interesting fish,” Navarro said.&Բ;“I always thought it looked like a shark because of its body morphology. And the tail is very shark-like. It can get very large, 6 to 8 feet in length, but you don’t have to be afraid of them. They’re not going to eat you.”

The sturgeon mainly consumes smaller crustaceans such as crayfish, worms, leeches, and other smaller water-dwelling creatures. The sturgeon also doesn’t have any teeth, so it has to swallow its food whole, much like a catfish.

Two adult sturgeon swim freely in an aquarium tank. The tank is much like the rocky terrain they typically inhabit in search of small prey. Source: Ohio Department of Natural Resources Division of Wildlife

Sturgeons were considered a nuisance by fishermen on the Great Lakes. They were plentiful and would frequently be caught alongside other fish. Their meat was good eating but they caused problems for the fishermen who were not looking to catch them. Because of the sturgeon’s size and strength, they would tear up the fishermen’s nets, said Tory Gabriel, the extension program leader and fisheries educator for . Frustrated fishermen would frequently pile thousands of the fish on shore and set them on fire.

Starting in the 1800s, the sturgeon began to become the source of a growing food trend: caviar.

This led to thousands of eggs being harvested from sturgeon and to overfishing, which harmed the populations of young fish in the streams and rivers where they were born. Christine Mayer, an ecology professor in the Department of Environmental Sciences at the University of Toledo, said the sturgeon have not been seen in the Maumee  River for the last 100 years.

“They’ve been gone for quite a while. Lake Erie was the highest catch harvest of lake sturgeon out of the Great Lakes, most of it from the Western Basin, so they were really hammered,” she said.

When a sturgeon breeds, it will return to the water source in which it was born, typically a small stream or river, and lay its eggs. When the baby sturgeon hatch, they live in the waterways,  slowly move further down the river system as they grow and eventually end up back in the Great Lakes.

Another reason for the sturgeon’s struggle to survive is the specie’s long lifespan.

“It takes females 20 years or so to be sexually mature and able to reproduce. So it takes a long time for them to come back. And if they don’t have the proper spawning areas,” Mayer said, “then that just coming back doesn’t happen on its own anymore, unfortunately.”

One good thing sturgeon have going for them is their size. Once they grow past a certain point, they have no natural predators. And after they reach sexual maturity, they will continue to reproduce every two to three years for the rest of their lives.

The U.S. Fish and Wildlife Service, the Ohio Division of Wildlife, the University of Toledo and the Toledo Zoo & Aquarium have worked the last few years to return the sturgeon to their natural spawning grounds. Starting in 2018, their first mission was to replenish the population of the Maumee River.

POSTED: Wednesday, April 26, 2023 09:41 AM
Updated: Wednesday, May 3, 2023 09:42 AM