Parks Canada has achieved a milestone in the restoration efforts for a threatened fish species in Banff National Park. The westslope cutthroat trout, after over a decade of dedicated work, is now naturally spawning and repopulating Hidden Lake near Lake Louise. Shelley Humphries, an aquatics specialist for Parks Canada’s Lake Louise, Yoho, and Kootenay field unit, expressed satisfaction that the trout population is becoming self-sustaining.
The process began in 2011 to remove brook trout naturally, which was later replaced with the use of rotenone, a natural fish poison, in 2018 and 2019. Starting in 2021, eggs were introduced into Hidden Lake annually for four consecutive years, resulting in successful spawning and the appearance of fully grown fish this year.
Humphries emphasized the importance of monitoring the situation and expressed hope that the westslope cutthroat trout will expand their habitat by utilizing streams and creeks beyond Hidden Lake. She noted the positive status of the trout population and the expectation of seeing them spawn in streams in the future.
Westslope cutthroat trout, once abundant in Banff National Park, faced a decline due to recreational fishing and the introduction of non-native species like brook trout in the early 1900s. This led to a significant reduction in the trout’s traditional waterways, with only about 10% of their original habitat remaining. Humphries acknowledged the past mistakes and highlighted the correctability of the situation, stating that the fish are highly salvageable.
Parks Canada is actively engaged in similar conservation projects at various locations including Helen Lake, Cascade Creek, Katherine Lake, and Corral Creek. Additionally, plans are in motion to extend similar restoration efforts to the threatened bull trout species. Humphries emphasized the ecological benefits of preserving at-risk species, mentioning the positive impact on other wildlife such as birds of prey and bears compared to non-native brook trout.
The overarching goal for Parks Canada is to protect species at risk and ensure they are not lost without a fight. The agency remains committed to these efforts to safeguard the biodiversity of Banff National Park and beyond.
