downstream from their tagging location. The highest densities of 

 adult walleye were found in the upper one-third of Garrison 

 Reservoir (Berard 1980) . 



Homing to the Intake spawning area from one year to the next 

 was high. Several studies have found evidence of homing behavior 

 in walleye (Forney 1963, Cowe 1962, Olsen and Scidmore 1962). 

 Olsen et al. (1978) hypothesized and Olsen and Scidmore (1962) 

 provided evidence that homing behavior in walleye is learned. This 

 tends to suggest that as walleye continue to spawn successfully in 

 the lower Yellowstone River, spawning numbers should increase. 

 Angler Harvest 



A total of 2,311 walleye were tagged from 1974 through 1980 

 and during this time 5 percent (108) were returned by fisherman; 

 most were caught in Garrison Reservoir, North Dakota. The low rate 

 of returns suggests that the harvest rate is not excessive. 



Ph ysical Requirements for Sauqer and Walleye Reproduction 



Intake 

 Spawning Critera 



During April and early May of 1977, 1978, and 1979; 233, 238 

 and 148 Stizostedion sp. eggs were collected on the Intake gravel 

 bar to determine sauger and walleye spawning criteria for depth, 

 mean velocity (measured at 0.6 the depth) and substrate. Walleye 

 and, to a much lesser degree, sauger were found spawning in the 

 mainstem of the Yellowstone downstream from Intake diversion and 



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