during the spawning run in 198 0, however, ranged from 94 to 4 04 cfs 

 (Figure A-27) . 



The number of male sauger collected in the Tongue River on a 

 river km basis was lowest in 1980 and highest during 1979 (Figure 

 4) . To make comparisons between years, however, a qualification 

 must be noted. The 220 V electrof ishing gear used in 1980 and 1979 

 was approximately twice as effective in catching sauger as was the 

 110 V gear used during 1976-1978. This was determined by sampling 

 with both types of gear during 1979. So, if figures for the years 

 1976-1978 are multiplied by a factor of 2, the maximum number of 

 males collected ranged from 36-48 per km during 1976-1978. This 

 compares nicely to the 38 sauger collected per km during 1979 and 

 isolates 1980 as an odd year when a maximum of 11 males sauger per 

 km were captured, only 25% of that for the previous years. 



Spawning success in the Tongue River during 1980, estimated 

 from the maximum drift rate of larval fish, was one third of that 

 of the previous year (Table 24). Unlike other years, in 1980 

 numbers of male sauger in the Tongue River never reached one 

 distinct peak. Instead, two major declines were evident including 

 one in the middle of the run when the river discharge declined to 

 300 cfs (Figure A-27) . Apparently a flow of 300 cfs is not 

 sufficient in the tongue River to stimulate continued sauger 

 presence or movement into this tributary. The second peak in male 

 sauger numbers in 1980 may be from a movement of sauger out of 



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