Study Finds Fish Passing Dams, Moving Across Red River System

Recent data from an IJC-funded study suggests that important fish species in the Red River are swimming nearly its entire length throughout the year, crossing dams where fish passageways have been installed.

This fish telemetry study has been ongoing since 2016, when it was initiated by the University of Nebraska-Lincoln and the Department of Fisheries and Oceans Canada with funding from binational partners including the IJC’s International Watersheds Initiative (IWI).

The study uses radio tags inserted into captured fish to see where they move throughout the Red River basin, including the river, its tributaries and into Lake Winnipeg. About 250 “listening stations” span the Red River into Lake Winnipeg and the Assiniboine River to track tagged fish as they go about their lives.

The project targets lake sturgeon, a culturally important fish to the Indigenous people in the basin. Sturgeon has been actively stocked through the Red Lake Nation and Minnesota since 1997 to help populations recover from a historic decline in the 1800s, caused primarily by dam construction. Additionally, project members have tagged a variety of other fish over the years, such as bigmouth buffalo (designated a Species of Special Concern under the Canadian Species at Risk Act of 2011), channel catfish, walleye, sauger, freshwater drum, burbot, lake whitefish and nonnative common carp.

In 2023, researchers tagged 34 fish with acoustic transmitters, mostly bigmouth buffalo and freshwater drum along with some lake sturgeon. Knowing when and where these species are moving is important for restoring populations of bigmouth buffalo and other species to help identify critical areas for spawning and rearing.

“Bigmouth buffalo are moving really vast distances,” said Marshall Stuart, a University of Nebraska graduate student involved in the study. “We’re seeing some patterns where the fish are moving upstream in the fall and overwintering in the U.S., and moving downstream in the spring to presumably spawn, potentially in the La Salle or Seine rivers or some other tributaries.”

Meanwhile, Stuart said, lake sturgeon tagged in 2021 along the Otter Tail River (near the Red River’s headwaters) are moving throughout the entire Red River system, showing up as far downstream as Lake Winnipeg.

This isn’t necessarily easy for these fish.

The Red River and its tributaries feature a variety of low-head dams across their lengths. In recent years, the US Army Corps of Engineers has been modifying or removing dams in the system to improve connectivity for fish passage and spawning; this telemetry program can help see how well it’s been working.

Of 77 “major barriers” in the system, 41 have been modified or removed, according to the project’s 2022-2023 report. In September 2023, the Drayton Dam became the latest such dam, with the installation of a fish ramp built out of rock and cobble, Stuart said. 

The Drayton Dam as seen in 2022 and 2023, before (left) and after (right) a fish passageway was installed to allow a variety of species to swim upstream. Credit: Marshall Stuart

Drayton was the last unmodified dam on the US stretch of the main stem of the Red River, but there are others on some tributaries. Newly installed telemetry stations along the Red Lake and Otter Tail rivers will help identify how fish are using those tributaries and if any dams are impeding movement, Stuart said.

“In the past we’ve seen fish have moved into the Red Lake River, but we didn’t know how far they were going,” Stuart said. “With receivers we can see how far they’re going and how they’re using it throughout the year.”

The Red Lake Nation has been stocking lake sturgeon into Red River tributaries with the Minnesota Department of Natural Resources serving as coordinator, ensuring that these fish have full access to preferred spawning habitat is important for restoration efforts, said Mark Pegg, University of Nebraska-Lincoln fisheries ecologist and project lead.

IJC funding for this telemetry study has been allocated through 2024 by way of the IWI, though Pegg hopes to keep the project going for as long as project partners can continue to get support.

 “I don’t know what the end date would be, but given that Fargo (Moorhead Area) Diversion is coming online and they’re in construction now, there are big questions to be answered on how modifying the river is going to impact the fish access up- and downstream,” Pegg said.