Lake sturgeon were having yet another of the species’ moments in late April.
First, they made the morning headlines April 22 by not landing on the nation’s endangered species list. The Center for Biological Diversity claims lake sturgeon are “imperiled,” and had petitioned the U.S. Fish and Wildlife Service to put them on the ESL, even though the species is doing well in Wisconsin and elsewhere.
Hours later, the prehistoric fish made more headlines when news broke of a Wisconsin-based lake sturgeon turning up in a research net 651 miles from home on the Mississippi River between Illinois and Missouri.
In other words, just another day in the media spotlight that shines often on Wisconsin’s “dinosaur fish,” our version of charismatic megafauna. Heck, watching lake sturgeon spawn is even a spectator sport each April in east-central Wisconsin, with cars, pickups and SUVs lining roadsides along the Wolf River near towns like Shiocton.
And why not? Besides elk, deer, wolves and black bears, no other species of Wisconsin fish or wildlife generates news by simply showing up unannounced on distant doorsteps with neither maps, visas nor travel vouchers.
In case you missed it, the wandering Wisconsin sturgeon that showed up 20 miles north of St. Louis hails from the Chippewa River waterway, and was identified by a numbered “Floy tag” in its dorsal fin. It’s roughly 30 years old, and was captured by Missouri Department of Conservation biologists at the Lock 26 dam near Alton, Illinois, on the Mississippi.
Wisconsin Department of Natural Resources biologists tagged the fish at least 10 years ago while it spawned below the Jim Falls dam in Chippewa County, north of Lake Wissota. The DNR said the fish’s interstate journey is the farthest recorded for that population of lake sturgeon. It had to pass downstream through three dams on the Chippewa River to reach downtown Eau Claire, and then swam freely for 60 miles to reach the Mississippi River. From there, it passed through 22 dams to reach its capture site between Illinois and Missouri.
We’ll never know for sure, but this sturgeon could have originated even farther up the Chippewa River above Jim Falls or possibly the Flambeau River. Lake sturgeon live in all Chippewa River impoundments upstream of Lake Wissota, as well as in the Flambeau.
At risk of making this a competition, lake sturgeon from the Winnebago System in east-central Wisconsin have traveled even farther. Ron Bruch, formerly the Wisconsin DNR’s lake sturgeon biologist, recalled several Winnebago System fish swimming all the way to Lake Erie after navigating the lower Fox River’s 17 locks or 12 dams between Lake Winnebago and Green Bay.
Ohio biologists identified the sturgeon by their Wisconsin DNR fin tags, which were attached on the Wolf River below the Shawano Dam during spring spawning runs. Margaret Stadig, the DNR’s senior fisheries biologist in Oshkosh, said one of those long-haul sturgeon was tagged in 1977 and caught in Lake Erie in 1982. Another sturgeon, tagged in 1978, showed up in Lake Huron in 1994 and then in Lake Erie off Port Clinton in 1997. Conservatively speaking, that’s 675 water miles from Shawano.
But what causes lake sturgeon to embark on long trips, with little or no likelihood of ever returning? Although sturgeon can slip downriver through a dam’s spillways during high-water periods, they can’t reverse course and power their way upstream over or through the dams’ gates or spillways.
And even if they could make such journeys, it’s not clear they have the desire. Bruch said lake sturgeon lack the spawning instincts and predictability of salmon or trout, which try to return to their exact places of origin.
“We’ve caught female sturgeon spawning along the Wolf River one year, and then the next time they spawn, we caught them somewhere up the Embarrass River,” Bruch said. “We’ve even had male sturgeon spawn on the upper Fox River, return downriver to the Winnebago chain, and then go up the Wolf River to spawn again a few days later.”
These long-lived, far-swimming fish speak to the overall health of myriad lake sturgeon populations around the Great Lakes. Joe Gerbyshak, the DNR’s fisheries biologist in Eau Claire, said the Chippewa River’s lake sturgeon populations are showing consistent growth.
Gerbyshak and his DNR crew spent April 22-25 surveying lake sturgeon below the Chippewa River dam in Eau Claire as the fish prepared to spawn. They caught 129 adult lake sturgeon during the four-day survey, the most adults they’ve netted during this annual effort. He said the sturgeon’s spawning “window” lasts two to three days once water temperatures trigger the activity, usually in late April.
This year’s catch included a record-size fish, a 64-inch, 75.5-pound female caught April 25. Gerbyshak said this sturgeon was last caught in 2015 at the same site, and that it had grown 2.7 inches since then. That sturgeon also weighed 30.2 pounds more than nine years ago, but it’s possible it wasn’t ready to spawn when caught in 2015.
Based on that survey, Gerbyshak estimated the lower Chippewa River has a spawning stock of 414 lake sturgeon, which was the first time the DNR was able to calculate that population estimate.
Gerbyshak said the DNR was relieved the F&WS declined to put lake sturgeon on the ESL.
“We didn’t think listing them was warranted,” he said. “Wisconsin has worked very hard to help lake sturgeon, and we felt there wasn't much more we could do for them that we weren’t already doing. Our water quality has improved, we’ve controlled the harvest, we’ve done extensive habitat work and restoration, and we’ve raised young lake sturgeon in our hatcheries and re-established their populations in the Milwaukee River and other systems. We’re also helping other states rebuild their sturgeon populations. Our budgets and staffing are tight. Listing lake sturgeon as endangered would have redirected work we’re now doing for other fish that need it more.”
Bruch also agreed with the F&WS’s ruling.
“Lake sturgeon in Canada and the U.S. are in pretty good shape, overall, and they’re much better off than they were 100 years ago,” Bruch said. “They aren’t in danger of going extinct, not by any means. Their populations and age structures are still rebuilding. As that continues, we’ll learn their actual life-expectancy. I’m sure some of them will live past 150 years. That simply couldn’t happen 50 to 100 years ago, before the states stepped up their management efforts.”
DNR fisheries biologists Heath Benike, left, and Joe Gerbyshak check and measure a 75.5-pound lake sturgeon the agency netted April 25 in the Chippewa River near downtown Eau Claire during the fish's annual spawning run. — Patrick Durkin photos
DNR fisheries biologist Joe Gerbyshak, left, shows off a young lake sturgeon while fisheries tech Matt Andre prepares to hoist a mature lake sturgeon from a holding tank.