DWR conducting upcoming waterbody treatments in High Uintas to help restore native cutthroat trout

Vernal — For the third consecutive year, the Utah Division of Wildlife Resources will be coordinating with the Ashley National Forest to conduct follow-up treatments to two drainages in the High Uintas to help restore native Colorado River cutthroat trout.

Over the past decade, DWR biologists have treated different waterbodies on the north and south slopes of the Uintas with rotenone to help with native cutthroat trout conservation. The treatments consist of using rotenone to remove non-native fish from the areas where native cutthroat trout will be restored.

Rotenone is a natural substance that comes from the roots of a tropical plant in the bean family. It's a respiratory toxin to fish, but it is not dangerous to people, pets or other wildlife, especially in the extremely low quantities that biologists use to treat streams and lakes. However, there will be a lot of crews and equipment in the area during the treatments, and the U.S. Forest Service will be closing the impacted areas. The public should stay out of these areas during the treatments, so the DWR can safely and effectively complete the projects.

This year, biologists will be conducting the treatments in the following areas in the High Uintas:

• Oweep Creek drainage (south slope) from July 28-31. (The area should reopen to the public on Aug. 2.)
• South Fork Sheep Creek (north slope) on Aug. 28. (The area should reopen to the public on Sept. 2.)

Since these are follow-up treatments, the DWR will not issue any emergency fishing changes for any of the lakes or drainages, as there should be very few fish in the systems at this time.

"The temporary closure of the treatment area only affects treated waters and prohibits the public from entering the water and obtaining drinking water from sources in the treatment area. All hiking trails and other access will remain open to public use," DWR Northeastern Region Outreach Manager Tonya Kieffer-Selby said. "The treatment areas will be well signed and will reopen after the treatment process is over and rotenone levels are no longer detectable in the streams."

A series of two to three treatments is the standard protocol for effective cutthroat trout restoration. For Oweep, this will be the third year of treatment and for the South Fork of Sheep Creek, this is the second year. There may be another treatment in 2025 on the South Fork, but that will depend on what biologists find in this year's treatments.

Why rotenone treatments are done

In addition to increasing the diversity of angling opportunities, these project treatments will help the native fish and ensure cutthroat trout populations improve. Habitat loss, spawning with non-native trout and competition from non-native trout have caused dramatic declines in native cutthroat trout populations around the West, leading to concerns about the species' future.

"As the trustee and guardian of wildlife in Utah, we're conducting Colorado River cutthroat trout restoration work across the fish's native range," DWR Regional Sportfish Biologist Bryan Engelbert said. "The activities will protect the species, while also providing people with great areas to fish for these native species."

The treatments will remove the brook trout, non-native cutthroat trout and rainbow trout currently found in the streams. Biologists predict that brook trout populations could completely replace cutthroat trout in these areas in less than 20 years without intervention. The goal of this work is to create a population of cutthroat trout that will contribute to the conservation of native cutthroat trout species and prevent them from being listed under the Endangered Species Act.

After the treatments

Biologists plan to restock the Oweep Creek drainage in the fall of 2024 after the treatments have been completed. The South Fork of Sheep Creek will not be restocked until the treatments are complete, most likely in 2025. The north slope treatment is part of a larger effort to treat the upper portions of streams connected to the Sheep Creek canal.

Restocking efforts in other locations, such as the East and West Fork of Carter Creek, have already begun.

Angler opportunities

Even though brook trout are being removed from these treatment areas, anglers can still find them in thousands of streams and lakes throughout the Uinta Mountains. Information about different fishing opportunities is available on the Utah Fish Planner map on the DWR website, so the public can easily find waters to fish by species.

The DWR plans to continue providing abundant angling opportunities for several species, including both brook trout and cutthroat trout, in the Uinta Mountains. To learn more about the cutthroat trout restoration happening in the Uintas, listen to the latest Wild podcast episode.

If you have questions about the treatment, call the DWR's Vernal Office at 435-781-9453.