Comparisons of the Effects of 10-Inch, 8-Inch, and No Minimum Length Limits onthe Smallmouth Bass Population and Fishery in Nebish Lake, Wisconsin

摘要

Smallmouth bass Micropterus dolomieui in Nebish Lake were studied during 1972-1988 to compare the mean population statistics and fishery parameters under three minimum-length-limit regulations. No length limit was in effect during 1972-1976, whereas an 8-in minimum limit and a 10-in minimum limit were in effect during 1977-1981 and 1982-1988, respectively. Mean total length of harvested smallmouth bass was larger under the 8-in limit than during the period without a limit, and mean length was larger under the 10-in limit than under the 8-in limit. Mean annual exploitation rate for age-3 fish decreased from the no-limit and 8-in-limit periods to the 10-in-limit period. The reduced exploitation rate resulted in a higher survival rate for age-3 fish during the 10-in-limit period than during the no-limit and 8-in-limit periods. The increased age-3 survival rate during the 10-in limit resulted in higher age-4 population and biomass sizes than during the periods with the less restrictive regulations.