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BULLETIN OF THE BUREAU OF FISHERIES 
INTRODUCTION 
In 1927 the Wisconsin Geological and Natural History Survey and the United 
States Bureau of Fisheries instituted a cooperative study of the life histories of the 
fishes that inhabit the lakes of the highland district of northeastern Wisconsin. By 
the arrangements agreed upon, the survey furnished facilities for the conduct of field 
operations and staff members of the two organizations cooperated in the collecting and 
investigation of the research materials. The limnological laboratories of the survey 
at Trout Lake, Wis., served as headquarters for all field operations. 
During the summer and early autumn of 1927 Dr. Stillman Wright of the Bureau, 
with the aid of an assistant made collections of fishes from several lakes of the region. 
In 1928, when it was impossible for Dr. Wright to be in direct supervision of the field 
work, the collections were made by Dr. Joseph Goldsmith and an assistant. A part 
of the collections for the years 1927 and 1928 served as a basis for a preliminary report 
on the growth of the rock bass in Trout and Muskellunge Lakes (Wright, 1929). 
In 1929 Dr. Wright found it necessary to devote his entire time to limnological investi- 
gations on Lake Erie and collecting operations were suspended during that year. 
The collection of data for the investigation of the life histories of the fishes of the 
region was resumed in 1930. During this season the field work was carried on by Dr. 
Edward Schneberger of the survey and Dr. Ralph Hile of the Bureau. (In 1931 the 
collecting of materials was continued under the supervision of these 2 investigators 
with the aid of 2 assistants.) In 1932, when it was impossible for Dr. Hile to partici- 
pate in the field operations, the collections were made by Dr. Schneberger, aided by 
one assistant. 
Although the materials collected have afforded data on a number of species, the 
investigations have centered upon the life histories of three forms: The yellow perch, 
Perea flavescens Mitchill; the rock bass, Ambloplites rupestris Rafinesque; the cisco or 
lake herring, Leucichthys artedi (Le Sueur). Dr. Schneberger has given his attention 
to the study of the perch and Dr. Hile to the study of the rock bass and the cisco. 
The small collections of game fishes collected in the various years formed a part of the 
material used by Juday and Schneberger (1930, 1933) in their studies on the growth of 
game fishes in Wisconsin. 
The ultimate aim of these studies of the fishes of northeastern Wisconsin is a 
more precise evaluation of the various environmental factors in their relation to the 
growth and abundance of the different fish forms. Since 1925 the survey has been 
conducting extensive limnological investigations on the lakes of the region. 2 The fish 
collections that were made for the growth studies have served also as material for 
study by survey staff members of food habits and parasitic infestation in the 
various species. The general consideration of the relationship between growth and 
environment awaits the termination of these several lines of investigation. In the 
present publication references will be made to relationship between growth and 
certain environmental factors, but no exhaustive discussion of the question will be 
undertaken. 
In the investigation of the ciscoes an attempt was made to select the populations 
for study from “type” lakes. The selection of the four lakes with which this study 
ispn^rily concerned was based principally on the amount of fixed CO, present in 
» For a history of the survey’s operations consult Juday and Birge (1930). Annual summaries of the survey’s activities appear 
in the Bureau’s reports on Progress in Biological Inquiries (Eich, 1926; Higgins, 192Sa, 1928b, 1930, 1931a, 1931b, 1932, and 1933). 
