Mark J. Fincel, Cameron W. Goble, Eli A. Felts
Landlocked Chinook salmon (Oncorhynchus tshawytscha) are a popular sport fish in Missouri River, USA, reservoirs. These fisheries are maintained through stocking, but few studies have examined specific factors at the time of stocking that may influence post-stocking survival of Chinook salmon. In this study, we used an information theoretic approach to evaluate the ability of candidate models to explain variability in the return of stocked Chinook salmon to a spawning station in Lake Oahe, a large Missouri River reservoir in central South Dakota. The best candidate models to explain adult Chinook salmon returns included the lake elevation in May and, to a lesser extent, the number of Chinook salmon stocked. Surprisingly, recruitment of Chinook salmon exhibited an inverse relationship to lake elevation. Models that included measures of predator and prey abundance showed little support. Thus, it appears that Lake Oaheâ??s fish assemblage at the time of stocking plays less of role in the return of Chinook salmon to the spawning stock compared to the lake characteristics at the time of stocking.
