Effects of Discontinuing Walleye Stocking on Fish Populations in Lake Thirteen

摘要

Fish community responses to discontinuing walleye Stizostedion vitreum stockingwere monitored during 1986-1996 in Lake Thirteen, a 222 ha north-central Minnesota Lake. Responses were compared to natural population fluctuations in a 54 ha reference lake (Sand Lake). The effect of discontinued walleye stocking, along with a apparent lack of northern pike Esox lucius recruitment, was to decrease the relative abundance of younger age predators in Lake Thirteen. Yellow perch Perca flavescens was the species most sensitive to changes in the predator populations. Increases in relative abundance of small yellow perch coincided with reductions in numbers of small walleye and northern pike.