Catch Rates and Catchability of Walleyes in Angling and Spearing Fisheries in Northern Wisconsin Lakes

Abstract

We examined relationships between angling and spearing catch rates (catch/h) and walleye population density (number/acre) in 118 northern Wisconsin lakes to determine if walleye catchability in these fisheries was density dependent. The densities of both adult and total walleye populations were unrelated to lake surface area. Similarly, the catchability of walleyes in angling and spearing fisheries was unrelated to lake surface area. Angling catch rates of walleyes were linearly related to total walleye population density, whereas spearing catch rates of walleyes were exponentially related to adult walleye population density. Walleye catchability in the angling fishery was not significantly related to population density, whereas walleye catchability in the spearing fishery was inversely related to population density. We conclude that walleye angling is density independent and is therefore self-regulating, whereas walleye spearing is density dependent and is therefore not self-regulating.