Sustainable Exploitation Rates of Walleye II: Alternative Regulations and a Changing Climate

We have developed general theory for estimating sustainable exploitation rates for walleye (Sander vitreus) based on life history variation and climate. Although preliminary results suggest that walleye can support a rate of fishing mortality that is approximately equal to natural mortality rate, we have so far assumed a simple regulation whereby length at capture was equal to length at maturity. In this study we relaxed this assumption to include the suite of walleye regulations that is found in North America (simple bag limits, minimum size limits, slot limits, “1 over” limits, etc.). We found that the amount of fishing mortality that a population could sustain depended strongly on the type of regulation, the length limit(s) associated with a particular regulation, and climate. Using these results, we then provide state- and province-specific management advice with respect to walleye regulations and fishing mortality rates under both contemporary and changing climates.