least 8 km between the release and recapture location of the fish 

 was necessary before it was considered movement. Recaptures caught 

 at the same location during the same season of the same year were 

 not included in movement analysis. 



Population and standing crop estimates were obtained for the 

 spawning walleye population downstream from Intake diversion, 1978 

 and for the Yellowstone River sauger population at Miles City, late 

 summer-autumn, 1978-1980. Fish were captured with electrof ishing 

 gear and a multiple census technique was employed using the 

 Schumacher-Eschmeyer estimate (Ricker 1975) . Population statistics 

 were computed with the aid of a computer program (Penkal 1981) . 

 Fish were aged by reading scales which were collected from an area 

 below the first dorsal fin and above the lateral line. Cellulose 

 acetate impressions of all scales were examined at 66 x 

 magnification. 



Daily flow records and water temperatures were obtained from 

 U.S. Geological survey Water Resource Data. Constant recording 

 thermographs were installed at various locations where the 

 Geological Survey did not have temperature recording stations. 



RESULTS AND DISCUSSION 

 Life History and Population Statistics of Sauger 



Chronology and Abundance During Spring 



Ripe male sauger were present in the lower Tongue and Powder 

 rivers during the last week of March through the first week of May 



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