Upper Shields River closed to recreation as brook trout removal begins

WILSALL — Twenty-seven miles of the upper Shields River will be poisoned to remove brook trout to preserve the northernmost habitat for Yellowstone cutthroat trout.

The Custer Gallatin National Forest has issued a special closure order during the time of the project to recreational access during the treatment.

This ongoing project, which began in 2022, is a collaboration between Montana Fish, Wildlife & Parks and the Custer Gallatin National Forest.

Yellowstone cutthroat trout have declined throughout much of their native range primarily due to competition and hybridization with nonnative trout species and habitat loss. Yellowstone cutthroat trout populations have especially declined in the upper Shields River watershed, largely due to the invasion of nonnative brook trout.

The project