Soda Butte Creek in Yellowstone National Park is widely regarded as one of the most beautiful trout streams in the entire world. Throughout its reaches, anglers can fish for cutthroat and cutthroat-rainbow hybrid (cuttbow) trout, and its upper reaches holds brook trout that rise eagerly to dry flies. Soda Butte is a healthy, vibrant fishery. But the presence of brook trout, an invasive species, has many worried for the troubled, native Yellowstone cutthroat trout. Pure-strain Yellowstone cutthroat trout are struggling to survive throughout much of the park's range but are thriving in Yellowstone's Lamar River, into which Soda Butte Creek drains. Concern over Soda Butte's brook trout population is so significant, that the park is considering poisoning the upper portion Soda Butte to eradicating all trout in the creek and restocking it with pure-strain Yellowstone cutthroat trout.
The proposed action is part of a planned cooperative effort between the National Park Service and partner agencies Montana Fish, Wildlife & Parks, the Wyoming Game & Fish Department and the U.S. Forest Service. The project would target brook trout and hybridized cutthroat trout, but would also kill any other fish in the project area -- Soda Butte Creek and its tributaries upstream of Icebox Canyon. Overall, 38 miles of stream are targeted. Removal would be accomplished via the application of an EPA-approved piscicide (rotenone), which is a naturally occurring plant compound that degrades quickly and does not persist in the water supply.
According to the project's proponents, removal of all fish in the upper Soda Creek is the most practical course of action given that two decades of mechanical eradication efforts (manual removal of brook trout and other target species via electrofishing) has failed to wipe out brook trout populations.
Montana Fish & Wildlife's environmental assessment of the project states that "Soda Butte Creek presents an opportunity to work towards several goals and meet some objectives. By removing nonnative brook trout from the upper Soda Butte Creek watershed, project partners are working to ensure the long-term, self-sustaining persistence of Yellowstone cutthroat trout within its historic range. Brook trout pose a threat to the Soda Butte Creek population and they are spreading downstream into YNP. Given the ability of brook trout to displace Yellowstone cutthroat trout, they are a risk to not only Soda Butte Creek, but the entire Lamar River watershed. Removing brook trout would contribute to securing Yellowstone cutthroat trout throughout the Lamar River watershed, which is among the conservation objectives in the MOU. Removal of the existing hybridized fish is also consistent with goal of maintaining genetic integrity. Although existing fish are slightly hybridized, they remain a source of nonnative genes to Soda Butte Creek and the Lamar River watershed."
But opponents of the project claim the four-agency partnership proposing the actions is grossly overreacting, citing the impacts that the project will have on angling in Soda Butte -- most notable amongst them the fact that angling opportunities on upper Soda Butte will cease to exist for many years. But objectors also call the project a waste of money, calling Soda Butte's brook trout a non-threat to Yellowstone cutthroat populations elsewhere in the park -- noting the long-time presence of brook trout in the creek's upper reaches, and the continued decline of their population thanks to electrofishing efforts.
Anglers are widely divided on the issue, perhaps due mostly to the health and excellent angling opportunities that currently exist throughout the entire length of the creek. In order to determine whether the project will proceed, Yellowstone National Park and Montana Fish & Wildlife are accepting public comments until June 13th. To make your voice heard, visit http://fwp.mt.gov/news/publicNotices/environmentalAssessments/conservation/pn_0026.html.