Propagated Fish in Resource Management

Short-Term Survival of Small Walleye Fingerlings Stocked into Wisconsin Lakes

Jeffrey M. Kampa, Martin J. Jennings, and Gene R. Hatzenbeler


Abstract.—We evaluated the short-term survival of stocked walleye Sander vitreus fingerlings during 1997 through 2002 in lakes with no natural reproduction. Lake surface area ranged from 40 to 160 ha. The stocked fingerlings were reared in 0.2-ha, plastic-lined ponds at the Governor Tommy G. Thompson State Hatchery in Spooner, Wisconsin and stocked during early summer. Stocked fingerlings ranged from 30 to 45 mm in total length and were stocked at densities of 124/ ha (N = 18) or 248/ha (N = 8). Fall electrofishing surveys were conducted on all lakes after surface water temperatures were < 22°C. The Serns’ Index was used to predict fingerling abundance, which was then used to calculate percent survival for the 3-month period between stocking and fall sampling. Mean survival was 0.4% (SE = 0.1%; N = 26) and ranged from 0.0% to 2.9% for all lakes. Fall fingerlings were not detected for 15 of the 26 stocking events. Stocking density did not appear to be important in determining contribution to the fall fingerling population. The current stocking program for lakes lacking natural reproduction has the potential to establish low-density populations of adult walleye. Creel data showed stocked fisheries in the northern third of Wisconsin provided a mean harvest rate of 0.021 (SE = 0.0042; N = 18) walleye per hour of directed effort or one walleye harvested for every 48 h of directed fishing effort. In comparison, the harvest rate for lakes supported by natural reproduction was approximately four times higher (mean = 0.079; SE = 0.0056; N = 158).