Michigan Department of Natural Resources
Fisheries Research Report No. 1794, 1973

The Standing Crop of Fish in Michigan Lakes


James C. Schneider


      Abstract.-Estimates of the standing crops of fish in 64 lakes and ponds in Michigan were summarized. The estimates were adjusted, when necessary, to include fish which were not estimated originally. Lakes with slow-growing bluegills had the highest total standing crops of fish, 182 pounds per acre. Lakes with only slow-growing yellow perch had the smallest fish crops, 46 pounds per acre. Lakes with fish populations of normal species diversity and growth averaged 88 pounds per acre. Other lakes, with poor or unusual fish populations, contained 104 pounds per acre. Multiple regression-correlation analyses were performed. Lake alkalinity, area, depth, alkalinity divided by depth (index), and the logarithm of each of these variables-these factors accounted for only 25% of the variation in the logarithm of fish standing crop when data from all lakes were pooled. Stratifying the data according to type of fish, and to trout lake versus warmwater lake, resulted in significant regressions. However, application of these results is limited because: (1) sample size was small in certain strata, (2) performance of particular variables in different regressions was inconsistent, and (3) the range in variables was relatively narrow.