MOVEMENT OF THREE SPECIES OF FISHES 



541 



E. C. GASTON J5/ 

 STEAM PLANT-^J 



Fig. 4 Plot of location of flathead catfish, Aug. 27 to Sept. 11, 

 1974. Dashed hne connecting positions ( C) indicates contin- 

 uous tracking. 



temperature was about 31°C. After a brief reacclimation period, the 

 fish was released in the Coosa River about 400 m below the steam 

 plant at 1110 hours on Sept. 4. Position plots represent 8 days of 

 tracking. This fish was not located after Sept. 19. Positions 2 to 10 

 represent 4 consecutive tracking days. Positions 11 to 17 were 

 recorded at intermittent periods between Sept. 10 and 19 (Fig. 5). 

 After her release, the fish moved rapidly toward the east side 

 (positions 1 and 2) and then upstream at a depth of 3 to 5 m 

 (positions 3 and 4). Her movement was not continuous but included 

 apparent stationary periods. She moved upstream past the thermal 

 zone within 3 hr (positions 5 and 6). As the fish moved past the 

 plant, transmitted temperatures were between 28.9 and 29.4°C, and 

 corresponding surface temperatures were 29 to 33°C. Swimming 

 depth was estimated to be about 3 m on the basis of vertical 

 temperature profiles. Upstream from the plant the fish appeared to 

 be deeper, about 5 to 7 m. Upstream movement stopped opposite 

 the mouth of the Yellowleaf Creek (position 7), and the direction 



