"[citation needed] The fish may have begun to disappear from the upper Muddy Creek in the 1850s as a result of physical changes made to the environment by travelers, the introduction of the brook trout and other non-native species, and possibly the over-trapping of beavers, which affected dams and dependent habitats.

[citation needed] While feared extinct, 8 isolated populations were discovered in and around the San Juan National Forest in mid-2018.

Shortly after the rediscovery of the San Juan cutthroat, their remnant populations were threatened by the 416 Fire, which was closing in on their remaining habitat.

In response, 58 San Juan cutthroats were removed from two remote creeks north of Durango and are being held in hatcheries, with the ultimate goal of captive breeding and reintroduction.

[4] The Wyoming Game and Fish Department in cooperation with the Bureau of Land Management, Little Snake Conservation District, the U.S.