LOW FREQUENCY TRANSDUCER 

 "WATER HAMMER" 



iPi^^ 5 MIN. CONTROL (NO SOUND) 



500- 



0-J 



39 



110 



83 



91 



93 



92 



98 



86 



88 



102 



10 MIN. CONTROL 



109 



108 



85 



94 



97 



103 



102 



96 



102 



103 



90 MIN. CONTROL 



313 



12 



52 



68 



67 



78 



117 



104 



49 



95 



16 HOUR CONTROL (OVERNIGHT) 



736 



44 



34 



13 



58 



Figure 8. Distribution of fish in pens, experiments 1-6. There were 100 fish 

 In each pen at the beginning of each experiaent. In controls, gates between 

 pens were lifted for periods indicated, then lowered. Tests differ only in 

 that sounds of Indicated frequencies (cycles per second) and durations were 

 applied at indicated location while gates up. Numbers and dark bars Indicate 

 number of fish in each pen after gates lowered. 



10 



