14. Comparison of the catch rates of shovelnose sturgeon with 

 the bottom profile of the river channel for one reach of 



the Tongue River 39 



15. Quadratic regression analysis of discharge versus catch 

 rates of shovelnose sturgeon in the Tongue River in the 



spring of 1975 41 



16. Quadratic regression analysis of discharge versus catch 

 rates of shovelnose sturgeon in the Tongue River in the 



spring of 1976 41 



17. Quadratic regression analysis of minimum and maximum water 

 temperatures versus catch rates of shovelnose sturgeon in 



the Tongue River in the spring of 1975 43 



18. Quadratic regression analysis of minimum and maximum 

 water temperatures versus catch rates of shovelnose 



sturgeon in the Tongue River in the spring of 1976 43 



19. Comparison of the linear regression analysis of the 

 weight at tagging versus the weight at recapture of 

 monel- and anchor- tagged sturgeon over the three years 



of sampling in the Tongue River 45 



20. Weight-frequency graph of sauger collected in the spring 



spawning migration of 1976 in the Tongue River 49 



21. Comparison of the age and length frequency of sauger 

 taken in the spring spawning migrations of 1976 in the 



Tongue River 49 



22. Length-weight relationship equation of all sauger collected 



in the spring of 1976 in the Tongue River 50 



23. Plot of the quantity of sauger taken per interval of dis- 

 charge in the spring spawning migration of 1976 in the 



Tongue River 53 



24. Quadratic regression analysis of discharge versus catch 

 rates of sauger collected in the spring of 1976 in the 



Tongue River 53 



25. Plot of the quantity of sauger taken per interval of maximum 

 and minimum water temperatures in the spring of 1976 in the 



Tongue River 54 



26. Quadratic regression analysis of maximum and minimum water 

 temperature versus catch rates of sauger taken in the spring 



of 1976 in the Tongue River 54 



