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A COMPARISON OF THE GROWTH 
RATES OF BLUEGILL 
(LEPOMIS MA CROCHIR US) IN LAKE WINGRA AND 
LAKE MENDOTA, WISCONSIN 
Farouk El-Shamy 
University Wisconsin — Madison 
ABSTRACT 
 Adult bluegill grew faster in Lake Mendota than in Lake Wingra. The mean
lengths for three-, four-, and five-year-old Lake Mendota fish were 135,
163, and 181 mm, respectively. The corresponding values for Lake Wingra fish
were 125, 142, and 147 mm, respective 
ly. 
 Small fish from the two lakes (one- and two-year-old fish) had similar growth
patterns and grew at a rate similar to that of fish from other Wisconsin
lakes. The decline in the growth of Lake Wingra fish was attributed to the
disappearance of large predators and the successful reproduction of pan fish.
INTRODUCTION 
 Preliminary observations on fish of Lake Wingra and Lake Mendota suggested
marked differences in the growth rates of bluegill. Lake Wingra has been
characterized recently as having stunted or slow-growing centrarchids. Thus
a comparison between bluegill in the two lakes should be analyzed in relation
to the ecology of the lakes. Body growth as determined by annual marks on
the scales was used as a basis for comparison. Growth in length and weight
at different ages was considered important for later studies. The scale method
is a well-established technique (Van Oosten 1929, Hile 1941, Schuck 1949,
Regier 1962, Snow 1968, and Stucky and Harold 1971). 
Study Sites 
 Lake Wingra and Lake Mendota are located in Dane County at Madison, Wisconsin.
Lake Mendota is the larger lake with an area of 3938 hectares and a mean
depth of 12 m. The study area is located in the littoral zone along Picnic
Point at University Bay, which supports a bed of aquatic macrophytes dominated
by Myriophyllum spicatum. 
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