BAGGS - On Aug. 7, 800 Colorado River cutthroat trout were hiked into headwater streams of the Little Snake River in the Sierra Madres east of Baggs, as part of a multi-year, multi-agency project to restore the species to its native range.

Crews from the Wyoming Game and Fish Department and the Medicine Bow-Routt National Forest, used backpacks to carry the fry ,or young fish, to their new home in Haggerty, Bachelor, Vole and Deep creeks.

Colorado River cutthroat trout historically occupied portions of the Colorado River drainage in Wyoming, Colorado, Utah, Arizona and New Mexico. The species was the only trout found in the Little Snake River prior to settlement of the area during the early 19th century. By 1883, the West’s cutthroat populations had already been decimated due to importation of exotic trout via the newly completed transcontinental railroad.

By the mid-1880s, rainbow and brook trout fry were brought in from Wisconsin and California. Unfortunately, the brook trout ate cutthroat eggs and fry and competed with the native cutthroat for habitat and forage. The rainbows interbred with the native fish and hybridized the species. Cutthroat habitat and range diminished over time with the mining activity on Haggerty Creek. Biologists believe the Colorado River cutthroat occupies less than 14 percent of its historical range.

Green River Fisheries Biologist Bill Wengert says efforts to manage and increase the number of stream miles occupied by Colorado River cutthroat trout began in the 1970s.

"Beginning in the mid-1970s, headwater streams were closed to angling, non-native trout were no longer stocked, and fish barriers, like the one at Haggerty Creek, were constructed to prevent brook trout from moving upstream," Wengert said. "By the early 21st century, 111 miles of stream in the Little Snake River Drainage in Wyoming contained the cutthroat."

Wengert says barriers are a physical block or obstacle to the movement or migration of fish. They may be natural, such as a waterfall, or man-made, like the Haggerty Creek fish barrier.

"There are two natural and eight man-made fish barriers within the cutthroat restoration area," he said. "Barrier placement, along with chemical treatments to remove non-native fish, and stocking of pure Colorado River cutthroat, combine to protect and enhance cutthroat populations."

Water quality in the region has also been influenced by previous mining copper mining operations. After litigation, the Wyoming Department of Environmental Quality is testing treatment for mining contamination.