Midwest Fish & Wildlife Conference 2017

AUTHORS: Jason C. Doll, Ball State University; Andrew Bueltmann, Indiana Department of Natural Resources; Sandra Clark-Kolaks, Indiana Department of Natural Resources

ABSTRACT: Walleye Sander vitreus are one of the most sought after sport fish in Indiana. To meet this demand Walleye have been stocked in Monroe Reservoir since 1982 at an average rate of 36 fingerlings/acre. Previous research on yield-per-recruit models has provided insight into effects of various exploitation rates at multiple minimum length limits; however, exploitation for Monroe Reservoir Walleye is unknown. As such, a mark recapture study was conducted from 2015 to 2016. Walleye were tagged in early spring. Tag loss was estimated by double tagging every other Walleye. Non-reporting rate was estimated with an angler creel survey in 2015. Exploitation was estimated using the Ricker method at multiple levels of reporting rates. A total of 157 Walleye were marked with Floy tags in the spring of 2015 and angler reports were accepted through the summer of 2016. Overall, fifteen tags were reported with forty percent of the reported tags being from Walleye caught in the Monroe Reservoir tailwaters. Exploitation rate was estimated at 0.15, 0.22, and 0.44 at a reporting rate of 75%, 50%, and 25%. Maximum yield estimated from the yield-per-recruit models was achieved at an exploitation rate of 0.70 and minimum length limit of 406 mm. The probability of yield reaching 80% of the maximum yield under the current minimum length limit of 356 mm at exploitation rates of 0.15, 0.22, and 0.44 is 0.1%, 74.7%, and 100%. Our results suggest that an increase in the minimum length limit would increase yield if the reporting rate from the creel survey was moderate to high.