Appendix D. Distribution of expected catch rates for all lakes and all scenarios.
Catch rates at equilibrium are shown for all 157 lakes and all scenarios that vary density-dependent catchability, catch importance, and regional effects. Generally, the variation in catch rates declines with catch importance and density-dependent catchability. The figure helps illustrate the widespread collapses of walleye stocks in extreme scenarios of density-dependent catchability and regional effort.
FIG. D1. Harvest per unit effort at equilibrium with varying levels of density dependent catchability (DDC and b), regional effort, and catch importance (VL – very low, L – low, M – medium, H – high, and VH – very high; base – harvest rate at biological carrying capacity).