made to determine how their removal affects their population structure and to 

 determine what percentage of the younger bullheads must be removed to produce a vj gorous 

 popuj.ation. 



Lake herring : 



Minnesota /^-S-R Charles R. Burrows $9,200 



Minnesota commercial fisheries improvement - western Lake Supericr - The University of 

 Minnesota is making this study to obtain life history information on species associated with 

 the lake herring. Of special interest are food habits, distribution, and abundance. 



Lake trout : 



Michigan 4-2-R Myrl Keller $32,780 



Surveillance of lake trout restoration in Michigan waters of Lake Michigan - This project is 

 undertaken to assess and describe conditions of lake trout stocks. Investigations are con- 

 fined to the northerly areas of the Lake where hatchery-produced lake trout are being 

 released and where sea lamprey control efforts began. 



Minnesota A-38-R Charles Burrows $12,500 



Lake Superior commercial fisheries assessment studies - The primary aim of this work is 

 to ascertain the condition of the lake trout and other commercial fish stocks in Minnesota 

 waters of Lake Superior. To meet this aim, the progress and effectiveness of sea 

 lamprey control in local areas and the survival and dispersal of stocked lake trout are in- 

 vestigated. The abundance and distribution of other commercial fish populations, as well as 

 the commercial production, are also investigated. 



Wisconsin /i.-7-R Ronald Doff $30,000 



Assessment of lake trout restoration in the Wisconsin waters of Lake Michigan - This project 

 is a part of the broad assessment of fish populations, including lake trout, in Lake Michigan. 

 Fish samples, scales, stomachs, and other biological data, as well as statistical records 

 of the fisheries, are collected in Wisconsin waters of Green Bay and Lake Michigan. 



Rainbow trout : 



Utah 6-10-R Clair B. Stalnaker $18,8^0 



Investigation of the intensity of natural selection upon different pheno types (blood types) 

 of rainbow trout in commercial trout rearing ponds and reservoirs - The work is carried out 

 at the Utah Fish and Game Department's Experimental Fish Hatchery at Logan and the Utah State 

 University Fisheries laboratory. Information is obtained on blood groups among the breeding 

 stock of rainbow trout used as brood stock for the fingerlings that are given commercial 

 trout farmers. Also established are tests that will provide information on the genetic 

 control of the blood types found. The major aim is to eliminate undesirable genotypes from 

 the breeding population. 



Walleye : 



Wisconsin AFC-2 Russell Daly Completed 1967 



Walleye population study in respect to a possible commercial fishery - Walleye were tagged 

 and released between Port Wing and Superior Harbor on Lake Superior to estimate population 

 size and to observe migration. Age and growth determinations were made by examination of 

 scales. 



Ot hers : 



Arizona 6-1-R W. L. Minckley $9,363 



Investigation of commercial fishery potential in reservoirs - This project is undertaken to 

 investigate populations of buffalofish, carp, and threadfin herring in reservoirs in central 



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