Parks Canada has achieved a notable milestone in the restoration of westslope cutthroat trout, a threatened fish species, to its native habitat in Banff National Park. Following over ten years of dedicated efforts, the federal agency has observed the natural spawning and resurgence of these trout in Hidden Lake, located near Lake Louise.
Shelley Humphries, an aquatics expert for Parks Canada overseeing the Lake Louise, Yoho, and Kootenay field unit, expressed satisfaction in the self-sustainability of the trout population. She emphasized the significance of this accomplishment, noting that the successful reintroduction aligns with similar initiatives in the United States that have led to species recovery and removal from endangered lists.
The restoration work initiated in 2011 to eliminate invasive brook trout proved ineffective until rotenone, a natural fish toxin, was utilized in 2018 and 2019 to eradicate the brook trout population. This intervention, coupled with the strategic introduction of trout eggs into Hidden Lake annually since 2021, has resulted in successful spawning and the emergence of mature fish this year.
Continued monitoring is planned to ensure the trout’s expansion beyond Hidden Lake into streams and creeks. Humphries highlighted the positive population trend, emphasizing the importance of observing the trout’s spawning behavior in various waterways to secure their long-term sustainability.
Historically, westslope cutthroat trout inhabited a vast area from the northern to the southern regions of Banff National Park. However, the introduction of recreational fishing and non-native species like brook trout in the 1900s led to habitat degradation, restricting the trout to only 10% of their original waterways.
Humphries acknowledged the past mistakes that jeopardized the trout population but remains optimistic about the ongoing conservation efforts. She emphasized the correctability of these errors and the imminent rescue of the westslope cutthroat trout, affirming the importance of safeguarding endangered species like these fish.
Apart from Hidden Lake, Parks Canada is engaged in similar conservation projects at various locations, including Helen Lake, Cascade Creek, Katherine Lake, and Corral Creek. Plans are also underway to extend similar restoration work to the threatened bull trout population. Humphries emphasized the ecological benefits of preserving native trout species, highlighting their significance in supporting the broader ecosystem, including bird species and bears, over non-native species like brook trout.
The overarching goal for Parks Canada is to protect and preserve endangered species like the westslope cutthroat trout, ensuring their survival through proactive conservation measures. By prioritizing the preservation of at-risk species, Parks Canada aims to combat species decline and promote biodiversity within the national park.