CONTENTS 



Page 



Introduction 1 



History 1 



The project 2 



Acknowledgment 2 



Description of Upper Mississippi River 3 



General topography 3 



Navigation pools 4 



Characteristics of the fishery 4 



Fishing methods 4 



Kinds of fish 4 



Quantitative aspects 5 



Trends 5 



Methods 6 



Field operations 5 



Report form s 5 



Tabulating procedures 5 



General figures 7 



Number of returns 7 



Fishermen, trips, and hours 7 



Residence and distance travelled 7 



Catch composition 10 



Species composition of catch jq 



Composition by seasons, pools, and localities 10 



Fishing success 22 



Definitions and terms 22 



Success by seasons 22 



Success by localities 22 



Variation throughout the season 27 



Comparison of two years 3 1 



Influence of certain factors 35 



Fishing pressure 35 



Bait 35 



Time of day 37 



Sex of fishermen 37 



Water temperature ; 37 



Changes in water levels 39 



Weather, moon phases, etc 41 



Depth of snow 41 



Relationships and correlations 42 



Two successive years 42 



Sampling at intervals 45 



Possibilities for reducing the size of the sample 51 



Summary 57 



Literature cited gg 



