Many inland fisheries are supported by stocking of hatchery-produced fish, and fisheries managers often face difficult decisions regarding strain selection. Stocking evaluations designed to quantify differences in strain performance provide valuable data for designing stocking programs. Here, we use genetic tools to investigate capture rate of two strains of Muskellunge stocked in Wisconsin lakes. We genotyped a total of 1,011 Muskellunge at 13 microsatellites and used data from five reference populations to assign fish stocked in four Wisconsin lakes to their strain of origin. The strains stocked in these lakes were derived from Wisconsin populations in the Upper Chippewa and Wisconsin River drainages and from Leech Lake, Minnesota. Leech Lake Muskellunge demonstrated much lower capture rates than the Wisconsin strain, but results were variable, with a 10% capture rate of Leech Lake strain fish in Lake Monona and 2% capture rate in Lake Wissota despite similar stocking rates (~25%) in both lakes. We hypothesize that the higher capture rates of Wisconsin strain Muskellunge could be due adaptative advantages of the Wisconsin strain in these waters and suggest that managers continue to stock the nearest native (i.e. Wisconsin) strain to achieve the highest return on investment.
Keywords: Muskellunge, propagation, Wisconsin, Leech Lake, stocking evaluation, microsatellite, population genetics ms accepted
