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8 pounds (equivalent to 80 po\mds per acre), yet it remained clearer than pond 

 11. Other examples may be observed in the tabled data. Despite these varia- 

 tions, the carp and the chemical were considered generally effective for the 

 purposes intended. 



The use of the chemical deserves some further discussion. It cannot be 

 categorically stated that it had no effects beyond its intended function of 

 sustaining the turbidities. That the effects were limited, however, seems 

 evident from these considerations: 



1) The chemical had no observed influence on pH of the pond waters., or 

 on the production of plankton, acjuatic insects, or other invertebrate 

 forms o 



2) Survival of bass and bluegills was higher in the chemically treated 

 ponds than in the ponds made turbid by carp. 



3) Pond 9, which received a maximum amount of the chemical, produced a 

 greater weight of fishes than other ponds receiving lesser amounts. 



It was generally true, however, that production decreased with increase 

 in turbidity, and an increase in turbidity was in most cases proportional 

 to the amount of chemical used. 



4) While it was true that bluegill reproduction was greater in the carp 

 ponds than in the chemically treated ponds, it was also true that the 

 carp ponds yielded greater weights of young bluegills than the untreated, 

 clear ponds. 



Additional evidence can be marshalled on both sides of the question. Since 

 the effects were minimal, and the variations could be attributed to the demon- 

 strated individualities of the ponds, and since the results conform closely with 

 those from the farm ponds, the direct effects of the chemical are believed to 



