Fig. 16. — A carp-goldfish 

 hybrid collected from the pol- 

 luted upper Illinois Ri\er. Note 

 the eroded tail and fin.s. 



tants have been degraded by the activities of man (Fig. 

 16). Here and there man has tempered this degrada- 

 tion — wildlife refuges and public hunting and fishing 

 grounds have been established, and management of some 

 areas by hunting clubs has produced better habitats than 

 existed prior to this activity. 



We trust that the deleterious trends now apparent in 

 the Illinois River can be changed. Some of the knowl- 

 edge of how to do this is now available. More must be 

 gained. There must be the desire on the part of agricul- 

 ture, municipalities, industn', and individuals to trans- 

 late present knowledge into action. 



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I 



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23 



