Yellowstone Park to conduct invasive species removal to preserve cutthroat trout

Yellowstone National Park will conduct an invasive species removal project in the northern part of the park as part of an ongoing conservation effort to preserve native Yellowstone Cutthroat trout.

Beginning Aug. 31, Buffalo Creek, a tributary of Slough Creek, will be closed to the public from the northern park boundary downstream to the confluence with Slough Creek. The closure will last until Sept. 7.

Biologists remove invasive rainbow trout from the creek by applying the EPA-approved piscicide (fish poison), rotenone. The treatment will not affect the potability of water at Slough Creek Campground, which will be safe to drink. Signs will be posted notifying the public of the closures.

Invasive rainbow trout have been competing and hybridizing with native Yellowstone cutthroat trout in Slough Creek, Soda Butte Creek and the Lamar River. Removal of the rainbow trout source population, identified in Buffalo Creek is key to ensuring the long-term persistence of Yellowstone cutthroat trout in the Lamar River watershed, according to park officials.

Yellowstone cutthroat trout rarely occur in Buffalo Creek, but any captured by electrofishing prior to the project will be moved to waters outside the treatment zone.

Yellowstone cutthroat trout are the only trout species native to the park. They are the most ecologically important fish of the Greater Yellowstone Ecosystem and are highly regarded by anglers.

Genetically pure Yellowstone cutthroat trout populations have declined throughout their natural range in the Intermountain West due to competition with, and predation by, nonnative fish species, a loss of genetic integrity through hybridization and habitat degradation. Learn more about ongoing preservation efforts at Native Fish Conservation Program.