Glacier National Park just approved an ambitious and untested experiment at Gunsight Lake in the St. Mary watershed. The plan involves poisoning out the rainbow trout that were planted decades ago, then transplanting westslope cutthroat trout, mountain whitefish and bull trout into the lake – fish that were never there.
The project is rife with problems.
Gunsight Lake water quality is characterized in the environmental assessment as excellent and reflects “the pristine attributes that stimulated the creation of Glacier National Park and its designation as a Biosphere Reserve” yet this project will poison the lake, wetlands and three miles of the St. Mary River headwaters killing not only the rainbow trout they hope to eradicate but also amphibians, aquatic macroinvertebrates, zooplankton and other aquatic life.
Deploying this poison requires helicopters, motorboats, generators and other activities that violate the Wilderness Act. [Glacier Park is designated as recommended wilderness but under Park Service policy it is to be managed as if it were Wilderness.] The Park admits that the project will have short- and long-term adverse impacts to recommended wilderness through manipulation of the biophysical environment; the rotenone application equipment, motorized watercraft, water pumps, generator and helicopters; closing the area to the public; and mortality of native aquatic organisms. Yet, that won’t stop them!
After the lake, river and wetlands have been poisoned they will then plant westslope cutthroat trout back into the lake. They portray this as restoring pure strain, non-hybridized cutthroats but when you dig deeper the assessment discloses that they won’t necessarily be transplanting pure strain fish, seemingly because those fish will be there to feed the bull trout that they plan to introduce. The decision added mountain whitefish to the mix as an additional food source.
The environmental assessment has no analysis or even current monitoring data to determine impacts to the small core areas of bull trout that will serve as the donor fish for this project.
Glacier has no park-wide fisheries management plan – the one they proposed in 2016 has been abandoned in favor of site-specific projects that they can get money to implement. They also have not developed the plan for how they will propagate bull trout to transplant into the lake. It should be noted that the bull trout recovery plan for the St. Mary watershed includes actions to facilitate recovery in this unique population on the east side of the continental divide – it does not include anything remotely similar to this experiment!
This project has too many unknowns that will impact the Gunsight Lake and upper St. Mary River ecosystems. It will disrupt the healthy populations of bull trout in Slide and Cracker lakes. Bull trout may not even stay in the lake but instead try to return to their home lakes. History has shown us that tinkering with natural ecosystems rarely results in a successful outcome because we, as humans, do not comprehend the interconnectedness of the web of life. If non-native fish hadn’t been planted in Gunsight Lake then there would not be a need now to try to poison them out. The misguided planting of mysis shrimp impacted the entire fishery of Flathead Lake.
We should learn from history rather than repeating it.
Arlene Montgomery is program director for Friends of the Wild Swan.