15 WIN- 45,000 C.RS. 



51 



354 S39S 44 



563 



15 MIN. CONTROL 



52 



304 



15 



63 



62 



556 



15 MIN SIREN, 20,000 TO 50,000 C.P.S. 



53 



^4\= 167 



133 



58 



50 



102 



68 



81 



296 



54 



55 



15 



56 



481 



MIN. -60^00 



C.RS. 



=42= 



II 



III 



97 



75 



87 



72 



24 



Figure 17. Distribution of fish in pens, experiments 51-56. Kxperiments 51- 

 53, 55, 56 started with 1,000 fish in pen No. 1 (far left); 51i started with 

 1,000 fish in pen No. 10 (far right). In controls, gates between pens lifted 

 for indicated period, then lowered. Tests same, except sounds of Indicated 

 durations and frequencies (cycles per second) applied at indicated location 

 while gates up. Numbers and dark bars show distribution of fish after gates 

 lowered. 



21 



