1100 -I 



1000 - 



900 - 



-£ 800 - 



E 



:i700 - 



600 - 



500 - 



400 - 



300 



I 



# Average Length 

 Range 



t 



1964 66 



—I r 



68 69 



1^ 



70 



72 



1— 

 73 



74 



"T~ 

 75 



76 



Figure 32. Average length and length range of northern pike from 

 gill -net catches, Tongue River Reservoir, 1964-76. 



of northern pike from various habitats across North America generally range 

 between 1.5 and 4.6 kg/ha. The low population levels shown in this reservoir 

 are probably the result of poor habitat quality and the lack of natural repro- 

 duction. 



TABLE 29. Population estimates of northern pike determined from trap net 

 catches, Tong'je River Reservoir, 1974-76. 



Year 



Number 

 Examined 



Number 

 Recaptured 



Population 

 Estimate 



Confidence 

 Intervals^ 



1974 

 1975 

 1976 



169 



180 



85 



36 

 52 

 48 



272 

 228 

 138 



218-238 

 116-172 



^Confidence interval not computed for northern pike in 1974 due to variation 

 in recapture distribution. 



96 



