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Fish were collected in the Patuxent River estuary and transported to 

 the laboratory. The selected fish species inhabited ecologically different 

 sections of the estuary; therefore, the overall reactions of each species 

 were unique. 



Seven species of estuarine fish were exposed to fuller's earth and 

 natural sediment suspensions for timed periods and hematological changes 

 were noted. The effects of various concentrations of fuller's earth 

 suspensions on white perch gill tissue were determined. Oxygen consumption 

 rates of striped bass, white perch, and toadfish were measured in filtered 

 Patuxent River water and compared to consumption rates in filtered river 

 water suspensions of fuller's earth or Patuxent River sediment. 



Fish showed signs of stress in response to "suspended sediments in most 

 of the experiments. Results indicate that sublethal concentrations of 

 suspended solids can affect estuarine fish. 



Additional experiments are discussed in Appendixes A to D. 



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