13 



V, 



►) 



►5 



5 MIN. CONTROL 



I 



5 MIN.- 70 C.P.S. 



I 



5 MIN.- 70 TO 700 C.P.S. (ONE SEC. INTERVALS) 



i 



5 MIN. -80 C.P.S. 



I 



5 MIN. -90 C.P.S. 



5 MIN- 100 C.RS. 



1 



Figure 10.- -Distribution of fish in pens, experiments 13-18. Each experiment started with 1,000 fish in pen 

 No. 1 (far left). In control, gates between pens were lifted for indicated period, then lowered. In tests, pro- 

 cedure was the same, except that sounds of indicated frequencies (cycles per second) and durations were 

 applied at indicated location while gates up. Dark bars show number of fish after gates lowered. 



