PERCENTAGE OF FISH REMAINING IN PEN NO. ONE 

 PLOTTED AGAINST CONTROL AND SOUNO TESTS. 



SOUND WAVES WERE BEAMED TO HOLD FISH IN PEN ONE. 



NOTE THE TENDENCY FOR THE FISH TO LEARN 

 TO REMAIN IN PEN NO. ONE. 



52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 

 TEST NUMBER 



CONTROL TESTS • 

 SOUND TESTS X 



Figure 20. Effect of conditioning on e3q)arijnental fish. 



24 



