Wildlife managers in Yellowstone National Park are planning this week to release a fish toxin in Grayling Creek as part of a long-term plan to restore native fish populations to the waterway in the Madison River drainage.
Visitors are advised to avoid drinking water from Grayling Creek and nearby waters through the end of the month.
The process is aimed at ridding the creek of non-native brown and rainbow trout, species which have contributed to a decline in native cutthroat trout in park lakes, rivers and streams, according to a statement released by the park’s public affairs office.
Officials aim to restore native westslope cutthroat trout and Arctic grayling in Grayling Creek and other park waters.
Grayling Creek and its tributaries are located north of West Yellowstone in the Madison River drainage.
An interagency team of biologists will introduce a fish toxin into the streams this week as part of Yellowstone’s Native Fish Conservation Plan and Environmental Assessment, which was approved in May 2011.
Only waters within Yellowstone National Park will be treated, park officials said, and the project will not impact downstream reaches.
While the chemical Rotenone will be introduced in small quantities, visitors are advised not to swim in or drink from the streams now through August 30. Warning signs will be posted at all treated areas.
This year’s treatment is the first in a series that is expected to continue over the next two to three years. Treatments will be conducted until nonnative trout have been completely removed from the streams.
Biologists will then reintroduce genetically pure native Arctic grayling and westslope cutthroat trout to the streams. The long-term plan is not only to support native species restoration, but also for these streams to provide a brood stock population for future restoration efforts in the region.
More information on the park’s Native Fish Conservation Plan can be found online at the National Park Service website.
Contact Ruffin Prevost at 307-213-9818 or [email protected].