ABSTRACT 



Standardized methods are described for use of an index fyke net to deter- 

 mine annually the abundance of smolt mig-rations from the Kvichak River 

 system, Bristol Bay, Alaska. Details of the fyke-net construction are pre- 

 sented. The fyke-netting pi-ocedure and the fishing- season are discussed as 

 well as some of the more important river conditions for an effective fyke-net 

 site: water velocity and depth, channel changes, and debris. Annual indices 

 of smolt abundance for the years 1955 through 1959 are presented. Com- 

 parisons in the timing of migration between years are included. Results of 

 tests to determine the variation between sizes of catch and age composition 

 of fish taken in nets fished side by side and up and down river are described. 

 Information is presented showing that large parent escapements produced 

 large smolt migrations and small escapements produced small smolt migra- 

 tions. 



A sampling program of fyke-net catches to determine age composition is 

 described. Age composition has been based on length-frequency and scale 

 studies. Age composition for each year is presented. Smolt age composition 

 has been compared with fresh-water age composition of returning adults. 



IV 



