Parks Canada celebrates the successful return of a threatened fish species to its natural habitat in Banff National Park. After over ten years of concerted efforts, westslope cutthroat trout are now naturally spawning and repopulating Hidden Lake near Lake Louise. Shelley Humphries, an aquatics specialist within Parks Canada’s Lake Louise, Yoho, and Kootenay field unit, expressed satisfaction with the self-sustainability status achieved by the species.
The initiative to eliminate brook trout using natural means in 2011 proved unsuccessful, leading to the use of rotenone, a natural fish toxin, for brook trout removal in 2018 and 2019. Subsequently, the introduction of trout eggs into Hidden Lake over four consecutive years starting in 2021 resulted in successful spawning and the emergence of fully matured fish populations this year. Monitoring efforts will continue, with the aim of observing the trout utilizing streams and creeks beyond Hidden Lake.
Humphries emphasized the importance of witnessing the fish spawn in streams to ensure sustained growth, as some stream locations are anticipated to serve as future spawning grounds. The restoration efforts aim to undo the impact of recreational fishing and the introduction of non-native species like brook trout in the 1900s, which significantly reduced the westslope cutthroat trout’s habitat to just 10% of its original range.
Parks Canada’s commitment to protecting at-risk species extends to various projects in locations such as Helen Lake, Cascade Creek, Katherine Lake, and Corral Creek, with plans underway to address the threatened bull trout population. Humphries highlighted the ecological benefits of these efforts, particularly in supporting other wildlife like birds of prey and bears over non-native brook trout.
The overarching goal for Parks Canada is to safeguard endangered species and prevent their decline. The agency’s dedication to this cause is exemplified by its ongoing work to preserve and restore the westslope cutthroat trout population in Banff National Park.
