WILSALL – Montana Fish, Wildlife & Parks, in collaboration with the Custer Gallatin National Forest, will begin additional phases of an ongoing project to conserve native Yellowstone cutthroat trout in the upper Shields River watershed this summer.

Yellowstone cutthroat trout have declined throughout much of their native range primarily due to competition and hybridization with non-native trout species and habitat loss. Yellowstone cutthroat trout populations have especially declined in the upper Shields River watershed largely due to the invasion of non-native brook trout. To mitigate further decline and conserve Yellowstone cutthroat trout in the upper Shields River, FWP and the Custer Gallatin National Forest began removing non-native brook trout in 2022. This year, fisheries staff will continue removing non-native brook trout from several tributaries to the upper Shields River. The project area is a stronghold for a core conservation population of Yellowstone cutthroat trout at high elevations and the northernmost extent of their range.

Brook trout will be removed from the project area using a plant-derived fish toxicant called rotenone. Rotenone is routinely used in fisheries management and breaks down quickly in the aquatic environment. It offers an effective means of removing fish species that are incompatible with the management goals of a fishery without endangering the surrounding habitat. Crews will collect Yellowstone cutthroat trout from the project area before rotenone application and return them to the streams when the project is complete. Detoxification stations will be set up to ensure there are no negative effects to gill-breathing organisms downstream of the project area.

The first phase of this year’s removal efforts will focus on Dugout Creek for several days beginning June 20. The stream will be closed to recreational access during the treatment as indicated by signage at the site, but land-based recreation in the area will not be restricted.

The next phase of this year’s efforts will focus on other areas in the upper Shields River basin. The Custer Gallatin National Forest will issue a special closure order during the time of the project, which will occur over a two-week period starting July 8. The closure area includes all spur roads, trailheads, and recreational sites and amenities on the National Forest Service Road number 844 (Upper Shields River Loop Road), starting just past the Sunlight Creek Road. This includes Crandall Creek Cabin and Road, Shields River dispersed camping sites, and the Turkey Creek Trailhead but does not include Sunlight Creek Road. Visitors should refer to the Custer Gallatin National Forest alerts website or Facebook page for updated closure information.

FWP published an environmental assessment for this project in 2022, hosted public meetings and solicited public comments.

Media Contacts

Montana Fish, Wildlife & Parks: Chrissy Webb, 406-594-1186, chrislin.webb@mt.gov

Custer Gallatin National Forest: Morgan De Meyer, 541-350-4666, morgan.demeyer@usda.gov