Parks Canada has achieved a milestone in the recovery of a threatened fish species in Banff National Park. Over a decade of effort has resulted in the westslope cutthroat trout starting to spawn naturally and repopulate Hidden Lake near Lake Louise. Shelley Humphries, an aquatics specialist for Parks Canada, expressed satisfaction that the trout population is now self-sustaining.

The initiative to remove invasive brook trout began in 2011 but was unsuccessful. Subsequently, Parks Canada used rotenone, a natural fish poison, to eliminate brook trout in 2018 and 2019. Starting in 2021, they introduced trout eggs into Hidden Lake for four consecutive years, leading to successful spawning and the appearance of fully grown fish this year.

Humphries emphasized the importance of ongoing monitoring, with hopes that the westslope cutthroat trout will expand their habitat beyond Hidden Lake into streams and creeks. She noted that the overall trout population is robust and expressed a desire to witness spawning in streams, anticipating further expansion beyond the headwater lake.

The westslope cutthroat trout, once abundant from the northern to the southern end of Banff National Park, faced a decline due to recreational fishing and the introduction of non-native species like brook trout. This led to the displacement of the westslope cutthroat trout from 90% of its traditional waterways.

Parks Canada is dedicated to rectifying past mistakes and is actively working on similar conservation projects in various locations, including Helen Lake, Cascade Creek, Katherine Lake, and Corral Creek. Plans are underway to extend these efforts to protect threatened bull trout as well. Humphries highlighted the ecological benefits of these initiatives, not only for fish but also for other wildlife such as birds of prey and bears.

In line with its commitment to safeguard endangered species, Parks Canada aims to fiercely protect and preserve at-risk species like the westslope cutthroat trout. The agency’s efforts extend to maintaining a healthy ecosystem that supports a diverse range of wildlife and habitats.

[Image: Westslope cutthroat trout swim in Hidden Lake in Banff National Park. The fish species is threatened under the Species at Risk Act and Parks Canada is working to grow its population in several mountain lakes and creeks.]

Parks Canada is actively engaged in restoring the westslope cutthroat trout population in Banff National Park, with a focus on preserving biodiversity and ensuring the long-term sustainability of the ecosystem.