Management & Regulation Research: Evaluation of an Open Panfish and Closed Predator Fishery

Objectives of this research project are to test whether closing a lake to predator harvest augments predaceous gamefish populations and controls panfish population size structure.

Background

The problem of slow-growing or stunted panfish plagues many Wisconsin lakes. Management practices such as chemical treatment, size limits, and mechanical removal have resulted in limited and variable success. In addition, these practices cost too much in terms of money, time, and/or public opinion.

Previous research has demonstrated that panfish populations can become overabundant without adequate predation. Overabundance leads to stunted individuals since there are too many fish for the available food supply. Stocking predators has been tried as a management technique, but anglers catch the predators before benefits can be realized.

However, the public appears to understand long-term changes in population dynamics and thus may accept new ecological management alternatives. In a pilot study and a 1985 questionnaire, anglers felt that potentially improving panfish quality on Round Lake outweighed the disadvantage of going to other nearby lakes for predator angling experience. This technique may provide the means for inexpensive and passive management. Fewer panfish will result in better individual growth, more large fish in the population, and increased angler satisfaction.