Parks Canada is celebrating the successful return of a threatened fish species to its traditional habitat in Banff National Park. The westslope cutthroat trout, which has been the focus of conservation efforts for over ten years, is now starting to spawn naturally and reestablish itself in Hidden Lake near Lake Louise.

Shelley Humphries, an aquatics specialist with Parks Canada’s Lake Louise, Yoho, and Kootenay field unit, expressed excitement over the self-sustaining population growth. She mentioned that similar initiatives in the United States have resulted in positive outcomes, leading to the delisting of endangered species.

Efforts to remove brook trout from the area began in 2011 but were unsuccessful. In 2018 and 2019, Parks Canada resorted to using rotenone, a natural fish poison, to eliminate brook trout. Starting in 2021, they introduced trout eggs into Hidden Lake for four consecutive years, resulting in successful spawning and the appearance of fully grown fish this year.

Humphries highlighted the importance of monitoring the fish population and expressed hope that the westslope cutthroat trout will expand beyond Hidden Lake to utilize streams and creeks for spawning. The overall population numbers are currently promising, and Parks Canada aims to see the fish thriving in various waterways, not just in the headwater lake.

Westslope cutthroat trout, which historically inhabited a vast area from the northern to the southern end of Banff National Park in Alberta, faced habitat degradation due to recreational fishing and the introduction of non-native species like brook trout. This led to a significant decline in their presence, restricting them to only 10% of their traditional waterways.

Humphries emphasized the importance of rectifying past mistakes and expressed optimism about the rescue and recovery of the westslope cutthroat trout population. Parks Canada has ongoing conservation projects in other locations such as Helen Lake, Cascade Creek, Katherine Lake, and Corral Creek, and is planning similar initiatives to protect the threatened bull trout.

The ecological impact of preserving these species extends beyond the fish themselves, benefiting other wildlife like birds of prey and bears more than the invasive brook trout. Humphries reiterated Parks Canada’s commitment to safeguarding endangered species and ensuring their survival through proactive conservation efforts.