MOVEMENT OF THREE SPECIES OF FISHES 

 PAST A THERMALLY INFLUENCED AREA IN 

 THE COOSA RIVER, ALABAMA 



JERRY L. MOSS,* SITDHI BOONYARATPALIN, and WILLIAM L. SHELTON 

 Alabama Cooperative Fishery Research Unit, Auburn University, 

 Auburn, Alabama 



ABSTRACT 



Movement of ultrasonic-tagged largemouth bass and flathead and channel catfish 

 passing the thermally influenced area of the Coosa River, Alabama, adjacent to 

 the Ernest C. Gaston Steam Plant was studied during the warm part of the year. 

 The area of thermal influence changed with the seasons, and movement of 

 largemouth bass and catfish past the thermal zone was affected but was not 

 prevented. Movement patterns suggested that the fishes avoided passing directly 

 through the area of maximum temperature influence by traveling under or 

 around it; thus the heated water did not form an impassable barrier. 



Concern has increased in recent years regarding the effects of heated 

 discharges on the aquatic environment. The release of heated water 

 into a riverine habitat is a potential barrier to the passage of fishes. 

 Although many changes unquestionably occur when heated effluents 

 are released into an aquatic system, there is considerable disagree- 

 ment as to whether these changes are harmful or beneficial 

 (Alabaster, 1962; Cairns, 1969; Davies, 1966; Langford, 1971; 

 Nakatani, 1969; Proffit, 1969). Inasmuch as most power generating 

 stations must dispose of 50 to 65% of the energy they produce as 

 heat (Federal Power Commission, 1969, cited in Langford, 1972), 

 the disposal of heated water is expected to become an increasingly 

 serious burden on our aquatic resources. 



Since recent technological advancements in biotelemetry have 

 been especially useful in studies of fish movement in relation to 



*Present address: Game and Fish Division, Montgomery, Alabama. 



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