5 MIN.- 160 C.P.S. (INTERMITTENT) ONE SEC. INTERVALS 



tl 



I 



5 MIN. CONTROL 



32 



I 



5 MIN.- 140 TO 200 C.P.S. (SIREN EFFECT) 



>}: 



I 



10 MIN. CONTROL 



34 



■T 



23 



10 MIN.- 700 C.P.S. 



ft' 



20 MIN. CONTROL 



36 



^53J 36~ 



63 



48 



Figure 13.- -Distribution of fish in pens, experiments 31-36. All experiments started with 1,000 fish in pen No. 

 1 (far left). In controls, gates between pens lifted for indicated period, then lowered. Procedure same in 

 tests, except sounds of indicated duration and frequency (cycles per second) applied at indicated location 

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



12 



