Management & Regulation Research: Effects of a Minimum Length Limit and a Daily Bag Limit on a Smallmouth Bass Fishery

Objectives of this research project are to determine the effects of restrictive angling regulations (i.e., a 16-inch minimum length limit and a daily bag limit of 2) on angling pressure, population density, growth, harvest, and yield of Smallmouth bass in Pallette Lake.

Background

The change in Wisconsin´s bass management philosophy from maximum- to optimum-sustained yield has been based on data generated from models, not actual evaluations, of restrictions in size limits or bag limits.

Smallmouth bass populations in northern Wisconsin, where reproduction is adequate to sustain a fishery, rarely have substantial numbers of fish above 12 or 14 inches. The frequency of small fish in these populations suggest over-exploitation. Even subjected to a low angling pressure, the exploitation rate of 8-inch and larger smallmouth bass in Pallette Lake (a lake located 0.5 miles from the nearest road and having only carry-in access) during the late 1980s was 44%.

If Smallmouth bass are to be managed as a keystone predator, a substantial portion of the population must be approximately 12 inches or larger to maintain a density of smallmouth bass high enough to control forage fish and panfish effectively.

This study will determine whether high minimum size limits are a feasible alternative for managing smallmouth fisheries in infertile waters, or whether undesirable reductions in growth, survival, or catch occur.