MINNESOTA (Cont. ) 



5. Study of Relative Efficiency and Selectivity of Cotton and Nylon Experimental 

 Gillnets 



The project has been undertaken to determine the relative effectiveness of 

 cotton and nylon gill nets and to develop a factor whereby previously collected 

 catch data from cotton gill nets nnay be expressed in terms of nylon gill net 

 catches. The comparative selectivity of the two types of nets is determined. 



Statewide; began Jiine 1956, to close October 1957; W. J. Scidmore, Leader; 

 reports available. 



Address inquiries to: W. J. Scidmore, as in No. 2 above. 



6. Statewide Creel Census 



A quantitative as well as qualitative census is being carried out on 29 lakes 

 and 4 trout streams to determine total yield in terms of numbers and pounds; 

 relationship between fish population structure and size to yield; relative effi- 

 ciency of fishing by different methods; and, to evaluate effects of fish manage- 

 ment measures on yield. The stream census was designed to also check dif- 

 ferential vulnerability of two important trout species. 



Statewide; began December 1952, continuing; $93, 000; Merle Johnson, 

 Leader; reports available. 



Address inquiries to: Jerome H. Kuehn, as in No. 4 above. 



7. Investigation of Year Class Formation in Game Fish 



Studies are in progress to determine relative influence of physical, 

 chemical, and biological factors which affect the natural reproduction success 

 of northern pike and largemouth bass. Such work is intended as furnishing a 

 means of assessment of year class strength in the earlier stages of life of 

 more important game fish species. 



University of Minnesota cooperating; George Lake; began April 1955; 

 $12,800; Lloyd L. Smith, Jr., Leader. 



Address inquiries to: Lloyd L. Smith, Department of Entomology and 

 Economic Zoology, University of Minnesota, St. Paul, Minnesota. 



8. An Economic Evaluation of the Sport Fishery in Minnesota 



This is a project which is designed to give an accurate and reliable esti- 

 mate of the extent of the economic value of the sport fishery of Minnesota. 

 The first phase of the project, which is a survey by mail of non-resident fisher- 

 ment, is being carried out during the fall of 1956. The second phase is a sur- 

 vey by personal interview of Minnesota resident fishermen which will be carried 

 out during the fall of 1957. Both phases of this project will be carried out on a 

 scale large enough to give statistical reliability to within 10 percent. 



Headquarters - St. Paul; began October 1956, to close November 1957; 

 $200; Zane Scheftel, Leader. 



Address inquiries to: Zane Scheftel, Fisheries Research Unit, 400 Shubert 

 Building, St. Paul 2, Minnesota. 



9. Evaluation of Fish Management Operations 



Investigations are in progress in several management programs to deter- 

 mine their effectiveness and value to the over -all management effort. These 

 investigations are as follows: (1) Evaluation of artificial panfish removal 

 as a means of improving growth rates and average size of individuals in stvinted 

 panfish lakes, (2) a study of the results of stocking with stunted panfish obtained 

 from artificial population thinning operations, (3) evaluation of the use of refuge 

 nursery streams as a stream trout management technique, and (4) a study of 

 the effect of stream improvement practices on trout populations and fishing. 



Statewide; C. R. Burrows, Leader. 



Address inquiries to: C. R. Burrows, Supervisor, Fisheries Research Unit, 

 400 Shubert Building, St. Paul 2, Minnesota. 



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