Telemetry project sheds light on fish movement in both the U.S. and Canadian portions of the Red River Basin

Jun. 9—ON THE RED RIVER — Growing up in Laramie, Wyoming, Marshall Stuart heard about the Red River of the North and its reputation as one of the best channel catfish destinations on the planet.

So, when he learned about an opening to work on the river and its larger tributaries as part of his master's degree study, Stuart jumped at the opportunity.

The thought of learning more not only about catfish, but also walleyes, efforts to restore lake sturgeon populations in the Red River Basin and the plethora of other species that call the Red River home was too good to pass up, said Stuart, a graduate student at the University of Nebraska-Lincoln.

"It's a pretty awesome and unique opportunity to (work on a river) that is so well-known and recognized globally for catfishing and everything else," said Stuart, who earned his bachelor's degree in 2019 from the University of Wyoming.

Stuart is now immersed in the fieldwork portion of a multi-partner international study to learn more about fish movement in the Red River Basin as part of a high-tech telemetry project. The study, now in its eighth season, already has shed light on the travels of species such as channel catfish, lake sturgeon and freshwater drum, but there's more to learn about quantifying basin-wide movements of fish species in the Red River and its tributaries, Stuart says.

Specifically, Stuart's focus is on fish movement in the Red Lake River and the Drayton Dam area of the Red River, where a project to modify the dam to accommodate fish passage is underway.

"After that dam is modified, (fish) might actually come farther up than they were because they'll be able to pass it at different times of the year" than in the past, Stuart said. "There's a potential for them to move farther than they are."

Stuart and his faculty adviser, Mark Pegg, and recent UNL graduate Mike Pugh were in Grand Forks and East Grand Forks earlier this week hoping to catch two native nongame fish species — bigmouth buffalo and freshwater drum — on the Red and Red Lake rivers and surgically implant small transmitters in the fish as part of the study.

If time allowed, the trio would also implant transmitters into a few walleyes. Pegg, a fish ecologist and professor at UNL, has been studying the movement of fish in the Red River Basin for more than a decade, beginning in 2012 as the faculty lead in

a project to tag nearly 16,000 channel catfish,

mainly on the Manitoba side of the Red River.

Using a technique called electrofishing, which involves sending a pulse of electricity into the water via a series of metal "tentacles" — for lack of a better word — that hang below two booms at the front of the boat, catching the fish on this warm June morning wouldn't be a problem. The pulse of electricity temporarily stuns the fish, making them easier to scoop into the boat, but they quickly recover.

The problem was the sudden rise in water temperatures, which had jumped from 70 degrees to 80 degrees in a matter of days, thanks to a steamy start to the month of June.

That's too high to safely implant the transmitters, Pegg said.

"We can catch the fish, I think, but I'm not sure they would survive the recovery in the long term," he said.

The telemetry project, which began in 2016 in Manitoba and expanded south of the border in 2017, involves surgically implanting acoustic transmitters in several fish species in an effort to learn more about their movements. Receivers, or "listening stations," anchored throughout the basin then pick up the signals from tagged fish as they swim by. Each transmitter emits a unique frequency, allowing researchers to identify individual fish when data from the receivers is downloaded.

The project initially focused on channel catfish but later expanded to walleyes, saugers, lake sturgeon, bigmouth buffalo, freshwater drum, whitefish, burbot and carp.

Since the study launched, partners — including UNL, Canada's Department of Fisheries and Oceans, Minnesota Department of Natural Resources, North Dakota Game and Fish and the U.S. Fish and Wildlife Service — have implanted the transmitters in about 1,000 fish, including more than 300 walleyes in Lake Winnipeg, Stuart said. Meanwhile, more than 250 listening stations are anchored throughout the basin from the source of the Red River at Wahpeton-Breckenridge to Lake Winnipeg, throughout Lake Winnipeg and in several tributaries, including the Otter Tail, Red Lake, Assiniboine and Winnipeg rivers.

Canadian researchers oversee the fieldwork north of the border while UNL and the Minnesota DNR handle the bulk of the work in the U.S.

"So, it's pretty extensive coverage," Stuart said.

The UNL crew cut this week's trip to the Red River Valley short after implanting a transmitter in a single bigmouth buffalo they caught Tuesday morning, June 6, at the confluence of the Red and Red Lake rivers in East Grand Forks. Their abbreviated electrofishing effort yielded a variety of species within city limits, including catfish, redhorse, suckers, saugers and walleyes, including a particularly impressive 26-inch walleye that came from about 3 feet of water along the North Dakota shoreline.

Stuart inserted a numbered yellow tag near the walleye's rear dorsal fin before releasing it back into the river

The Nebraska crew will be back in mid- to late July to download data from the listening stations and ramp up their electrofishing efforts again this fall, when water temperatures cool to the point where they can implant the acoustic transmitters without overly stressing the fish.

Ideally, water temperatures should be cooler than 70 degrees.

The telemetry study, which is scheduled to continue at least two more years, already has yielded information that wasn't previously known. Freshwater drum implanted with transmitters near Drayton, for example, swam way into Manitoba for the summer, only to return to Drayton in the fall. A couple of catfish tagged in Manitoba actually showed up near the source of the Red Lake River at Lower Red Lake, and another catfish implanted with a transmitter near Grand Forks made a quick trip to Winnipeg, only to return to Grand Forks.

Two years ago, project partners put transmitters in 19 lake sturgeon in the Otter Tail River below Orwell Dam. Data from the listening stations showed 15 of them moved into the Red River, five swam all the way to Winnipeg and three of those five are currently below the power dam on the Winnipeg River in Pine Falls, Manitoba, Pegg said.

Bigmouth buffalo, meanwhile, have been shown to cover even more water.

"They don't look like real strong swimmers or big swimmers," Pegg said. "You just figure their home range is a couple miles or whatever, and that's definitely not the case."

As for walleyes, fish tagged in Lake Winnipeg rarely go past the St. Andrews Lock and Dam on the Red River in Lockport, Manitoba, but they've been shown to travel large portions of the massive lake, which covers nearly 9,500 square miles.

"They move big time in the lake," Pegg said. "They'll do a big circle, essentially, through the whole lake. Not all of them, but a lot of them do. So there's pretty much the same amount of movement in the lake as there would be in the river if they came into the river."

Stuart, whose time in the field continues through next summer, definitely won't lack data for his master's degree thesis. The goal this field season, he says, is to implant transmitters in 15 bigmouth buffalo and 15 freshwater drum on the Red River, primarily near Drayton. He also hopes to implant transmitters in 24 fish in the Red Lake River and has implanted three so far. The remaining 21, he says, will be split between walleyes and lake sturgeon.

That will make for a busy fall, once water temperatures drop.

"It will just kind of depend on conditions and how many fish we can get," Stuart said. "We're kind of at the mercy of getting those out when we can. It will be useful information, whether it's lake sturgeon or walleye."