(Figures 4 and 5) . Female sauger were also present in these two 

 tributaries as early as late March but were not collected in a ripe 

 or spent condition until mid April to mid May depending on the 

 year. 



It appeared that large numbers of male sauger moved into the 

 Powder River earlier than in the Tongue River. Maximum peaks 

 occurred 2 3 days earlier in the Powder than Tongue River during 

 1978 and 1977 and 14 days earlier in 1976 (Figures 4 and 5) . The 

 Powder was not sampled during the early period in 1980. Female 

 numbers appeared to peak slightly earlier in the Powder than Tongue 

 River (8 days in 1980 and 4 days in 1978) or simultaneously as in 

 1977 and 1976. 



Of the over 3,000 sauger captured in the lower Tongue and 

 Powder rivers during March-May, 1976-1980, over 90 percent were 

 sexually mature. Males comprised 84 and 79 percent of the sample 

 in the two rivers, respectively (Table 2) . 



When numbers of mature sauger peaked in the Tongue and Powder 

 rivers, numbers were at low levels or sharply declining in the 

 Yellowstone River near the mouth of these tributaries (Figures 4, 

 5, 6, 7, and 8). Mature sauger were not abundant at other 

 locations in the mainstem of the Yellowstone River (except 

 occasionally downstream from Intake diversion) at a time when 

 sauger were concentrated in the Tongue and Powder rivers (Figures 

 9 and 10) . 



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