Study Finds Fish Traveling Across Much of Red River Watershed

With fish passageways now in place across the whole Red River system and an expanded telemetry network, species such as lake sturgeon, bigmouth buffalo, walleye and freshwater drum appear to be traveling wherever they can find habitat, according to the latest update of a long-running study.

Since 2016, several organizations and agencies in Manitoba, Minnesota and North Dakota have monitored when and where target species of fish were moving in the Red River system. The project targets a number of species including lake sturgeon, bigmouth buffalo, channel catfish and freshwater drum, which move throughout the Red River. Other tracked species, such as common carp, burbot, walleye and lake whitefish, typically remain in Lake Winnipeg, but also move into the lower sections of the Red.

“When we started to discuss this (around) 2015 and 2016, we were mostly focused on walleye and catfish because we had preliminary information that showed catfish move around a lot,” said Mark Pegg, lead researcher and fish ecologist from the University of Nebraska. “It turns out they move the least amount of any species we study in the river— we thought they were big movers, but in relative terms they aren’t.”

Through years of effort, plus support from the IJC’s International Red River Watershed Board and International Watersheds Initiative, this monitoring network now extends into the Assiniboine River, Lake Winnipeg and several tributaries that connect to the Red, with hundreds of fish across eight species tagged with acoustic transmitters. 

This is important, as resource managers have been working to identify the primary ranges and habitats for these species to better define regulations and management efforts.

Lake sturgeon and bigmouth buffalo in particular tend to be very mobile in the Red River watershed, Pegg said, moving several hundred kilometers in a short amount of time. 

The earliest transmitter tags, implanted in 2016, have been reaching the end of their battery life, necessitating some additional tagging of lake sturgeon in recent years. 

A map of the receiver array from Lake Winnipeg down through the Red River system and its tributaries. The different colors denote different portions of the river system for analysis purposes. Credit: Marshall Stuart/Mark Pegg

In 2023, Drayton Dam was modified to a rock-arch rapid to promote fish passage; prior to that point it was the last remaining unmodified barrier on the US portion of the Red River. While the low-head dam is not entirely impassable, it was difficult to move upstream and the receiver network indicated fish seemed to mostly stay downstream of it until flows increased to a point that passage was more feasible. So researchers were interested in seeing how fish would respond to the newly modified structure. Additional telemetry stations have been installed near the dam to provide a refined picture of how the new structure may be impacting species; as of this writing the data were still being analyzed.

These new receivers also are newer models, said researcher Marshall Stuart, University of Nebraska graduate student. 

They’re designed to better detect tagged fish moving through noisy, turbulent environments, such as those above and below the Drayton Dam. Additional receivers have been installed downstream of Grand Forks, North Dakota, to increase the coverage density from 30 km to 15 km (about 9-19 miles). There are still eight acoustic tags that will likely go out in the spring of 2025 to help track sturgeon movements.

Receivers installed in the Red Lake River tributary in previous years also show sturgeon moving through the river and over the East Grand Forks rock arch, near the confluence of the Red River. The fish appear to be impeded by the Crookston rock-arch rapid, though, Stuart said, noting that one sturgeon traveled up to it and then turned around to go back downstream. The next round of data downloads will help identify if it is common for fish to not pass Crookston.

The research team is drafting a final report that should be completed by June 1, 2025. Stuart said there are still outstanding questions on how the ongoing Fargo-Moorhead diversion will impact fish movement, and if fish are taking advantage of the new passage project at Drayton Dam. The Fargo-Moorhead Diversion Project is a major flood control effort by the US Army Corps of Engineers and other partners to protect the region from Red River flooding, set to be completed by 2027.