MAMMOTH HOT SPRINGS, WY – From August 17-23, 2020, the following areas of the upper Gibbon River drainage in the central portion of Yellowstone National Park will close for native fisheries restoration work:
- Virginia Cascades Drive
- Wolf Lake Trail to Little Gibbon Falls (see map)
Campsites in the area will remain open. However, access to the sites may be impacted. Visit the Backcountry Situation Report for details. The closures are necessary for park staff to continue work on a project to eliminate nonnative fish from the upper Gibbon River drainage between Virginia Cascades and Little Gibbon Falls. Closures may lift if the project is completed ahead of schedule.
Biologists will remove nonnative rainbow trout and brook trout using the fish toxin, rotenone. Rotenone is a naturally occurring chemical compound derived from the roots of tropical plants. Below the treatment area, biologists will add potassium permanganate to the water to remove the effects of rotenone and prevent impacts to downstream waters. This is the final treatment to remove nonnative fish from this section of river. The reintroduction of native Arctic grayling and westslope cuttroat trout will continue as needed to restore these native species.
This work continues the park’s efforts to create refuges that support the introduction of westslope cutthroat trout and Arctic grayling. The historic stocking of nonnative fish nearly eliminated these species from Yellowstone. In recent years, the park has restored them to the East Fork of Specimen Creek, Goose Lake, and Grayling Creek. Planning documents describing this work can be found on the National Park Service planning website.