ABSTRACT 



This study of the whitefish fishery of Lakes Huron and Michigan includes: (1) a review of 

 the available statistics of production, 1879-1942; (2) a detailed analysis of the annual fluctua- 

 tions in the production and abundance of whitefish and in the intensity of the whitefish fishery 

 in the State of Michigan waters of the lakes, 1929-1942, with special reference to the effects of 

 fishing with deep trap nets; (3) an account of the bathymetric distribution and vertical move- 

 ments of whitefish and certain other species; and (4) a report of field observations made in 

 1931 and 1932, as related particularly to the destruction of undersized whitefish by pound nets 

 and deep trap nets. The main body of the manuscript and appendices A, B, and C, completed 

 in March 1942, contain statistics through the year 1939. Since that time, records for the 

 years 1940-1942 have become available. Because these additional data did not alter any of the 

 conclusions of the manuscript but actually strengthened them, it was not deemed justifiable to 

 expend the considerable amount of time and money that would be required to revise the study. 

 The 1940-1942 records are therefore presented in appendix D. 



From a relatively high production in the earlier years of the period, 1879 to 1942, the yield 

 of whitefish declined to a lower level about which the catch fluctuated until the late 1920's and 

 early 1930's when a general increase in production occurred. This recent increase was higher 

 and the subsequent decline more severe in the Michigan waters of Lake Huron than in other 

 areas. 



II 



