Life can be tough for a fish that may live 100 years, isn’t sexually mature until it’s 20 years old or more and feeds by sucking in worms, leeches, crayfish and fish at the bottom of rivers or lakes. Lake sturgeon have always seemed a little mythical to me—whether it was the picture of a giant one rising to the canoe of Hiawatha in a children’s book illustration or images of dried sturgeon stacked like so many logs to burn as fuel in steamboats in the 1800s (an early sort of biofuel?).
So it caught my attention when I heard Travis Moore, a fisheries management biologist with Missouri Conservation Department, talking enthusiastically about the sturgeon his team tracked moving up and down the Mississippi River. Travis leads a study on lake sturgeon that uses high-tech remote tracking systems placed in several locations in the river. So as the fish tagged with transmitters pass by, the receivers can identify which one it is and follow its travels.
The combination of damming, channelizing and overfishing knocked back the sturgeon population in North America. The good thing is in Missouri they’ve been produced at hatcheries and reintroduced beginning in 1984. Now these fish are just coming of age to create fertile eggs. So will they be able to do it?
The many dams along the Mississippi River present some big barriers to the sturgeon that would have been able to move much more up and downriver historically. Travis told me about one lake sturgeon, though, that made it almost to Hannibal, Mo., from 400 miles north in Minnesota where it had been tagged four years ago by the U.S. Fish and Wildlife Service. What’s amazing is that the 50-plus-pound sturgeon had made it through 16 lock-and-dams! To do that, it likely had to wait and enter each lock along with barges and boats and then move on through when the waters rose and the gates at the other end opened.
Travis said that there is also some discussion of a possible fish passage structure that would help fish move up the river to what might be better sites for the fish to lay and fertilize their eggs. Right now, a few of the lake sturgeon that have been raised in hatcheries and released at Hannibal are hanging out below the first dam they face going upriver at Keokuk, Iowa. Another group of fish released at Cape Girardeau have gone upriver to the first dam they reached just north of St. Louis.
It’s exciting to think that a fish that can grow to 200 pounds might once again thrive in our biggest rivers. In the meantime, the biologists are working to learn what it takes to help them succeed. For more information on lake sturgeon, check out Wisconsin’s site (the initial eggs for Missouri’s hatcheries to raise sturgeon came from Wisconsin), and the World Sturgeon Conservation Society.