PART IV 



OBSERVATIONS ON SOUND PRODUCHON AND RESPONSE IN TUNA^/ 



b7 



Iwao Miyake 

 Associate Professor of Physics 

 University of Hawaii 



INTRODUCTION 



At the outset of this investigation, two questions were asked, 

 Cl) do tuna produce sound, and (2) do tuna respond to sound stimuli? 

 If tuna produce sound, there was the possibility that their presence 

 in the open ocean naght be detected by the use of listening deviceso 

 If tuna responded to sound stimuli ^ there was the possibility that 

 the emission of sound of a certain quality and quantity might attract 

 them to a fishing vesselj or that the emission of sound of another 

 quality and quantity might repel them to practical advantage in fish= 

 ingj eogoj upwards from the lead line of a purse seine during pursing 

 operationso 



The exploratory observations reported below were conducted at 

 intervals from August 1951 to January 1952s on tuna confined in a 

 tank and a pond (Tester 1952) at the Hawaii Marine Laboratory 3 

 Coconut Island, Oahu, To Ho 



MATERIAL AND APPARATUS 



When the experiments were first conducted m the concjrete tankj 

 it contained but one yellowfin ( Neothunnus macropterus ) and a few 

 manini ( Acanthurus sandvicensis )o Later j another yellowfin and a 

 small tunny C E'-^thynnus yaito jlyere present o When the experiments 

 were conducted in the large pond, one yellowfin and one tunny were 

 present, along with several small reef fishes of various ^ecieSo 



Three dLfferenx types of borrowed eqiiipment were used during the 

 course of the worko These consisted of Model OAJ iioimd Measuring 

 Equipment (reception range^ 1 to 10 kilocycles per second) and Model 

 OCP-1 Sonar Test Equipment' (reception range 7 to 70 kilocycles per 

 secondi transmission range, 5 to 88 kilocycles per second) ^ both 

 loaned through courtesy of local representatives of the U.. S,, Navy<, 

 and NEL Underwater Sound Monitoring Equipment C^eception range, about 

 100 cycles to 10 kilocycles per second),; loaned through courtesy of 

 the Navy Electronics Laboratory, San Franciscoo In addition,, a 

 sound generator consisting essentially of a P-H (Packard-Hewlett) 

 audio oscillator (transmission range, 20 cycles to 30 kilocycles per 

 second) was also usedo 



Contribution Noo 25 of the Hawaii Marine Laboratory., University 

 of Hawaii. J Honolulu, Tc Ho 



59 



