Influence of the cessation of harvest on a formerly exploited Walleye population
Published in Transactions of the American Fisheries Society, 2026
Abstract Objective The decline of native Walleye Sander vitreus populations in inland lakes raises concerns about conservation and continued exploitation in these fisheries. Although Walleye have been intensively studied, available data on the long-term trajectories of exploited populations are limited. We tested for trends in the dynamics of an exploited Walleye population in Escanaba Lake, Wisconsin, following the implementation of a harvest-eliminating regulation in 2003.
Methods We used long-term fisheries-dependent and -independent surveys of the Walleye population of Escanaba Lake during 1982–2022 to test for regulation effects. We compared sex-specific mortality and growth before and after the no-harvest regulation was enacted. We also performed breakpoint analyses on annual estimates of density and age-0 relative abundance and Walleye-specific angler effort, angler catch per unit effort, and distance traveled by Walleye anglers.
Results Total mortality declined and there was a lower growth potential (von Bertalanffy ) for both sexes following the elimination of harvest. A rapid increase in density occurred during an initial recovery phase (2004–2008), which was followed by a decade of variability (2009–2022) that appeared to stabilize toward the end of the data set. The recruitment dynamics were decoupled from adult population responses, and no trends over time were detected with the breakpoint analysis. Walleye-specific effort declined following the elimination of harvest, yet catch rates remained dynamic and were not related to the regulation change.
Conclusions Our findings emphasize the importance of density-dependent processes and interannual variability when evaluating responses to regulations. Walleye populations may be capable of recovery when they maintain their productive capacity despite high harvest. We found that Walleye catch rates and age-0 recruitment may not be the best indicators of adult Walleye population dynamics. Implementing management strategies to ensure the resilience of Walleye populations under changing ecological and anthropogenic stressors will be critical to their long-term persistence.
Recommended citation: Preul-Stimetz, T. N., Shaw, S. L., Renik, K. M., & Sass, G. G. (2026). Influence of the cessation of harvest on a formerly exploited Walleye population. Transactions of the American Fisheries Society.
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