averaging 454 nm (17.9 in) in length and weighing 1044 g (2.30 lb) while 

 males averaged 374 mm (14.7 in) and 409 g (0.9 lb). Sauger taken in gill 

 nets from five sampling areas of the lower Yellowstone River exhibited 

 similar length and weight distributions (Peterman and Haddix 1975). 



The weight-frequency distribution of the 1976 sauger sample is shown 

 in figure 20. The peak of the sample occurred at 300 g (0.66 lb), with the 

 greatest abundance falling in the size class 200-350 g (0.44-0.77 lb). 

 Sauger length-frequency distribution for 1976 is shown in figure 21. 

 Lengths ranged from 250 mm (9.8 in) to 545 rmi (21.5 in) with the peak occurring 

 at 375 mm (14.8 in). Three age classes were evident, and scale samples showed 

 these ages to be IV (320 mm total length), V (375 mm total length), and VI 

 (430 mm total length). 



Using the 1001 lengths and weights and computing a linear regression on 

 the Log,„ of the weight (dependent variable) and Log-]o of the length 

 (indepenaent variable), the resulting equation is: 



Log w = 3.3438 log tl - 6.016 



with a correlation of r = 0.9577 (figure 22). The length-weight equation for 

 1.501 sauger from Lake Winnebago, Wisconsin (Priegel 1969) was: 



Log w = 3.1309 log 1 - 2.5091 



Age and Growth 



Scales from 274 sauger taken during the spring of 1976 were analyzed for 

 age and growth. Ages ranged from three to nine years, with age group IV the 

 dominant age (32.5 percent). Age groups IV, V, and VI made up 73.4 percent 

 of the total sample (table 11). Growth rates for the sauger collected in 

 the Tongue River are slower than those observed in other northern waters 

 (table 12). The Tongue River sauger were collected in the spring; growth rates 

 in other rivers may have allowed more of the season for additional growth. 



TABLE 11. Age and mean length of sauger taken in the Tongue River, spring of 



1976 



Age 



Number of Fish 



Mean Length (mm) 



Range (mm) 



III 



IV 



V 



VI 



VII 



VIII 



IX 



26 

 89 

 62 

 50 

 31 

 12 

 4 



289 

 332 

 374 

 418 

 444 

 478 

 544 



259-312 

 277-385 

 332-404 

 387-443 

 419-475 

 453-565 

 504-573 



48 



