Parks Canada has achieved a significant milestone in the restoration of a threatened fish species in Banff National Park. Following more than a decade of dedicated efforts, westslope cutthroat trout are 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 excitement over the self-sustainability of the fish. She highlighted the successful restoration work in the United States, which has led to the removal of westslope cutthroat trout from the list of threatened species.
Efforts to eliminate brook trout began in 2011 but were unsuccessful. In 2018 and 2019, rotenone, a natural fish poison, was used to eradicate brook trout. Subsequently, starting in 2021, eggs were introduced into Hidden Lake for four consecutive years, resulting in successful spawning and the appearance of fully grown fish this year.
Humphries emphasized the importance of ongoing monitoring and expressed the desire to see the westslope cutthroat trout expand beyond Hidden Lake into streams and creeks. The overall population numbers are promising, and the focus now is on observing spawning activities in various stream locations besides the headwater lake.
Westslope cutthroat trout, which historically inhabited a vast area from the northern to the southern regions of Banff National Park, faced habitat challenges due to recreational fishing and the introduction of non-native brook trout in the 1900s. This led to a significant decline, leaving them in only 10% of their traditional waterways.
Parks Canada aims to rectify past mistakes and is actively working on restoring the westslope cutthroat trout population in multiple mountain lakes and creeks. Additionally, plans are underway to extend similar conservation efforts to the threatened bull trout species. Humphries highlighted the ecological benefits of preserving at-risk species, emphasizing the agency’s commitment to safeguarding species in jeopardy.
The federal agency is engaged in similar conservation projects in areas like Helen Lake, Cascade Creek, Katherine Lake, and Corral Creek. They are also exploring future initiatives to protect bull trout. Humphries stressed the importance of protecting endangered species and expressed determination not to lose them without a fight.