Michigan Department of Natural Resources
Research and Development Report No. 279
Institute for Fisheries Research Report No. 1790, 1972
The Food and Feeding Habits of the Bluegill and
Yellow Perch in Lakes with Good and Poor Fishing
Percy W. Laarman and James C. Schneider
Introduction.-The bluegill, Lepomis macrochirus Rafinesque, and the yellow perch, Perca flavescens (Mitchill), are found in most inland lakes in Michigan, and are the most common panfishes in the the fisherman’s creel. Some lakes consistently produce bluegills and perch of desirable size, whereas other lakes are plagued with populations of slow-growing fish.
Studies of bluegill diets have shown that zooplankton and aquatic insects are usually the preponderant foods (Moffett and Hunt, 1945; Scidmore and Woods, 1960; Seaburg and Moyle, 1964). Plants are also eaten frequently and are sometimes the predominant food during the summer (Lux and Smith, 1960). In general, larger bluegills eat larger food items such as insects, whereas smaller fish take a greater proportion of zooplankton. However, Gerking (1962) found no difference in diet related to fish size in a stunted bluegill population. He did find that bluegills were selective in the size of zooplankton that was eaten.
The yellow perch feeds primarily on zooplankton, benthos and fish, but many kinds of food may be eaten (Pearse and Achtenberg, 1921; Adams and Hankinson, 1928). In most lakes entomostraca predominate in the diet of perch up to a length of about 70 mm, insects predominate in perch 70-150 mm long, and crayfish and fish predominate in larger perch (Turner, 1920; Nurnberger, 1930; Kutkuhn, 1956). In other lakes, where cladocerans or chironomids are the principal food, there is no marked change in the diet as perch grow. When preying on cladocerans both fingerling and adult perch select Daphina larger than 1.3 mm (Galbraith, 1967).
Laarman (1963) related growth rate of bluegills and perch to morphological and chemical characteristics of lakes in Michigan, in an attempt to classify bluegill and perch waters. He found no significant relationship between growth rate of bluegills and perch and the following parameters: lake size, mean depth, alkalinity, and turbidity.
The objective of this investigation is to determine the feasibility of using zooplankton and/or benthos as an index for classifying lakes for bluegill or perch management. For this study it is assumed that food supply in relation to feeding habits may be more significant than morphological and chemical characteristics of lakes, and may provide a better index for predicting the potential of lakes to produce desirable bluegill or perch populations.