What Impacts Return-to-Anglers of Landlocked Fall Chinook Salmon in a Large Reservoir?

Landlocked Chinook Salmon are a popular sport fish throughout the three largest Missouri River reservoirs. However, a paucity of literature examining factors that influence return-to-anglers of landlocked Chinook Salmon exists. Thus, we sought to identify specific variables that impact returns of Lake Oahe’s Chinook Salmon fishery. We formulated ten candidate models and used Akaike’s Information Criterion, adjusted for small sample size to determine which model best explained Chinook Salmon return-to-angler. The most supported model indicated that smolt size at stocking was inversely related to return-to-angler. Models indicating a positive relationship with Walleye catch-per-unit-effort and Rainbow Smelt abundance also received support. The lowest Residual Sums of Squares were exhibited in models that incorporated both smolt size and Rainbow Smelt abundance but corrections for sample sizes resulted in low weights for these models. Smaller size at stocking was associated with earlier stocking dates and time periods that corresponded to movement patterns in both Walleye (spawning movements away from smolt stocking locations) and Rainbow Smelt (spawning movement into smolt stocking locations) that appear to benefit smolt survival. Stocking Chinook Salmon smolts earlier may reduce exposure to predation pressure while utilizing a predation buffer species ultimately increasing post-stocking survival.