and 56 part-time Illinois River commercial fishermen in 1973, and 

 9 full-time and 47 part-time in 1971. Nor is it explained by a decline 

 in economic value of the catch. The catch from the Mississippi River 

 bordering Illinois has been relatively constant from 1950-1973. A 

 general decline in profits would be reflected in a general decline in 

 fishing effort in both the Illinois and Mississippi Rivers and a cor- 

 responding decline in catch. 



Some of the reasons for the changing distribution patterns and 

 abundance of Illinois River fishes will be discussed in more detail in 

 the next section. 



42 



