Stizostedion sp. eggs were similar these two years. In 1979, flows 

 were as high as 16,800 cfs during the spawning period and water 

 temperatures were 3.5 to 4 . O^C lower than 1977 and 1978. Maximum 

 egg abundance and number of mature walleye were sharply lower this 

 year. Allocated instream flows during April for the mainstem at 

 Sidney (rive km 56) is 6,808 cfs and should be adequate for 

 mainstem walleye and sauger reproduction. 



Fourteen walleye spawning sites, in addition to the one at 

 Intake, were located during 1980. The upstream and downstream most 

 sites were at river kilometer 163 (upstream from Glendive) and 26 

 (Montana-North Dakota border) . Few spawning sites were located 

 downstream from Sidney (river km 56) because of the paucity of 

 suitable substrate and lack of adequate velocities. Most spawning 

 sites were runs along the head or mouth of dry side channels or 

 along gravel islands. None of the sites, the largest being several 

 hundred meters long, were nearly as extensive as the Intake 

 spawning area. Spawning flows determined to be adequate for the 

 Intake spawning area would also probably be sufficient for these 

 other areas. To maintain the unique physical characteristics at 

 these sites a periodic bankful flow of 52,000 cfs is necessary in 

 2 of 3 years. 



Intake diversion does not block upstream migration of sauger 

 or walleye but does tend to concentrate these two species 

 particularly during spring and fall. At allocated discharges of 

 2670 and 3276 cfs during September and October migration over this 

 structure, particularly by young fish, may be greatly reduced or 



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