Effects of Special Harvest Regulations on Largemouth Bass and Yellow Perch inSpruce Lake

摘要

The objectives of this study were to determine the effects of special harvestregulations on fishing pressure, largemouth bass (Micropterus salmoides) and yellow perch (Perca flavescens) population density, growth, harvest, and yield in Spruce Lake. Following a 9-year fishing closure, experimental regulations (12-inch minimum length limit and bag limit of 2/day on largemouth bass and use of artificial baits only) were evaluated in Spruce Lake from 1 July 1986 to 31 October 1989. The average annual fishing pressure during this study was 28% lower than it was in the late 1970s when there were no special regulations. Anglers harvested 91 largemouth bass in 1986 compared with an average annual harvest of 30 bass during 1987-89. The mean length and weight of largemouth bass harvested increased from 12.5 inches and 0.92 lb in 1986, to 13.3 inches and 1.15 lb in 1989. Limited population data for adult largemouth bass indicated that bass densities declined from 15.0/acre in 1986 to 3.9/acre in 1989, while yellow perch density increased over 650%, from 356/acre to 1986 to 2,678/acre in 1989. The bag limit regulation reduced the largemouth bass harvest during the first 2 years only.