The ecology and population dynamics of fish that inhabit interconnected waterbodies are challenging to understand. Movement of fish among waterbodies presents difficulties in estimating population size and exploitation rate, and movement of native and non-native forage complicates food web dynamics. The Inland Waterway in northern Michigan is a lake chain that consists of four lakes (Burt, Crooked, Mullett, and Pickerel) and connecting rivers that contain walleye, which is a highly mobile species. Walleye within the Inland Waterway are harvested from two distinct fisheries; spearing and recreational-angling fisheries. Harvest quotas are based on spring mark-recapture population estimates of adult walleye for individual lakes using a closed population model and a constant maximum exploitation rate (u = 0.35) harvest control rule. I estimated the post-spawn movement and fishing mortality rates to determine the appropriateness of the current model assumptions for making harvest management decisions. I developed a tag-recovery state-space model fitted using Bayesian estimation techniques to determine the spatial structure of walleye populations in this waterway. Walleye moved extensively among waterbodies, with rates of moving out of a lake or river post spawn ranging between 0.10 and 0.82. This level of intermixing is substantial enough to warrant consideration in the population estimation and harvest allocation processes. I developed a stochastic simulation model to determine the influence of movement patterns on the application of the current harvest control rule. The total allowable catch needed to maintain the desired level of maximum exploitation (u = 0.35) on the individual spawning populations required lake-specific adjustments during the angling harvest period. Although adjustments were needed to meet target exploitation rates, current estimates of exploitation rate were low enough that no individual spawning population was being overexploited. Movement of non-native species into a lake chain system can negatively influence the foraging ecology of native predators. The Inland Waterway has experienced the secondary spread of round goby, alewife, and rainbow smelt from the Great Lakes. Prior to this study, little was known on how these non-native species have been integrated into the foraging pattern of the system's native top predator. Using stomach contents and stable isotope analysis, I determined that walleye foraging did not always follow the pattern that would be expected based on available literature. We also determined that the non-native round goby became a dominant portion of the walleye diets in Burt and Mullett lakes, which were the two lakes where round goby were abundant. In addition, we determined that walleye did not prey on non-native pelagic fish prey, despite the large area of pelagic habitat and established populations of alewife in Burt and Mullett lakes. This study illustrated that native predators in smaller inland lakes exhibit flexibility in their response to non-native species, but much like predators within the Great Lakes, predators from our smaller scale study lakes have integrated round goby into their forage ecology.
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