Michigan Department of Natural Resources
Fisheries Research Report No.1872, 1979
Effects of Regulations on the Fisheries of Michigan Lakes, 1946-65
James C. Schneider and Roger N. Lockwood
Abstract.-Creel census statistics and related data, collected 1946-65, are presented for 22 Michigan lakes where sport fishing regulations were tested. The main objective was to determine if increased fishing opportunity could be provided without damaging the populations or their fisheries. For panfish, removal of the closed spring season, removal of the 6-inch size limit, and removal of creel limits were tested. For game fish, length of the closed spring season, both high and low size limits, and a ban on northern pike spearing were tested. For rainbow trout stocked in lakes, spring and winter fishing seasons were tested. Most of the lakes were of the largemouth bass-bluegill type.
It was difficult to accurately discern the effects of the fishing regulations because of imprecise statistics, a large increase in fishing pressure following World War II, a widespread increase in fishing for bass coupled with a decrease in fishing for panfish during the 1950's, irregular recruitment, and other uncontrolled events. It is clear that, in general, no dramatic changes in fisheries or populations resulted; however, some experienced a gradual deterioration which may or many not be linked to the tests. It is recommended that game fish size limits and closed seasons be retained on most lakes in Michigan.
Pumpkinseeds, rock bass, black crappie, and in some lakes largemouth bass and smallmouth bass, were especially vulnerable to spring fishing. Size limits typically had strong effects on the catches of bass and northern pike, as predicted by Latta (1972, 1974, 1975).