For over half a century, the fish populations in the Williston Reservoir have undergone tremendous changes since the reservoir reached its full pool in the early 1970s. The transition from river to lake habitat brought about a shift in species composition, isolating fish upstream of the W.A.C. Bennett Dam.

Over the last few decades, various stocking efforts for Kokanee have introduced non-native stocks, which are now mixed with historically present populations in the watershed. With the continually evolving fishery in the Williston Reservoir, the BC Hydro Fish and Wildlife Compensation Program, Provincial Fisheries Biologists, UNBC Researchers, and Chu Cho Environmental have taken on a project to shed light on the abundance and genetic composition of the Kokanee populations in the reservoir.

Bryce O'Connor, a Fisheries Biologist with Chu Cho Environmental, leads the team of experts in their quest to understand the fishery. Marty Izony, who has been working with Chu Cho Industries for many years, uses a jet boat to navigate the rough waters of the Williston Reservoir. The team sets gill nets to capture the fish, which are then identified, measured, and aged, with genetic samples collected for further analysis. The odilith, similar to an ear bone, is extracted to determine age, while fin clips and muscle tissue are collected for genetic mapping and mercury content analysis in collaboration with researchers at the University of Northern British Columbia.

Nathan French, an Environmental Scientist with Chu Cho Environmental, explains the significance of this project and other ongoing studies in the territory. The goal is to protect the endemic fish populations impacted by the creation of the Williston Reservoir, while collecting valuable data on Kokanee and other species such as Bull Trout and Lake Trout. This project provides a unique opportunity to pool resources and gain a deeper understanding of this dynamic and evolving fishery.

With the findings from this project, we can gain valuable insights into the populations and ecology of the Kokanee in the Williston Reservoir, helping to protect this vital fishery for future generations.