Kejimkujik National Park in Nova Scotia has decided to halt its annual brook trout survey due to the detrimental impact of an invasive species on the local environment. Since the 1990s, volunteers, mainly fly fishers, have participated in the census by recording the number, weight, and size of brook trout they caught to aid Parks Canada in monitoring the species.
However, this year, the census has been suspended as chain pickerel, an invasive species responsible for the majority of fish caught in the national park in western Nova Scotia since 2025, has significantly affected the brook trout population. The presence of chain pickerel has reduced the number of brook trout reported in the census, making it challenging to maintain the statistical power required for the monitoring project, according to a spokesperson for Parks Canada.
Chain pickerel, introduced illegally to Nova Scotian waters in 1945, have rapidly spread throughout the province and were first detected in the park in 2018. Once established in a water system, chain pickerel aggressively dominate the ecosystem by preying on various species, including fish, reptiles, frogs, dragonflies, and even ducklings.
Efforts to mitigate the spread of chain pickerel within Kejimkujik, such as the installation of fish barriers, have been hindered by flooding. Despite the challenges, Parks Canada, with the assistance of volunteers, has successfully removed over 5,300 chain pickerel to date, emphasizing the mandatory retention of chain pickerel caught by anglers while native fish species, like trout, must be released back into the water.
To continue monitoring the brook trout population, Parks Canada will utilize alternative methods, including the angler diaries program and deploying fyke nets annually in various water bodies within Kejimkujik to track native fish populations. Conservationists are advised to shift their focus to areas not yet impacted by chain pickerel to prevent further proliferation of the invasive species.
Trevor Avery, a professor at Acadia University, has been studying chain pickerel in Kejimkujik since their introduction, analyzing their feeding habits. Avery highlighted the effectiveness of consistent fishing practices in managing the chain pickerel population, although eradication remains challenging.
Nova Scotia, renowned for its brook trout fisheries, faces the dual challenge of preserving native species like brook trout while managing the impact of chain pickerel. The history of exceptional fishing experiences in Nova Scotia, as depicted in “The Tent Dwellers,” offers anglers a unique opportunity to engage in recreational fishing activities.
Despite the setback caused by the invasive species, conservation efforts will persist to safeguard the biodiversity of Kejimkujik National Park.