RKACTION OF TUNA TO STIMULI, 1953 



By 



Albert L. Tester, Heeny Yuen, and Mlchio Takata 



INTRODUCTION 



During 1951 and 1952, studies of the response ol' tuna (mostly "little 

 tunny", Euthynnus af finis ) to stimuli were conducted in tanks and ponds of the 

 Hawaii Marine Laboratory at Coconut Island, Oahu, under contract (I6fw-13331 and 

 I6fw-18564) between the University of Hawaii and the U. S. Department of the In- 

 terior, Fish and Wildlife Service, Pacific Oceanic Fishery Investigations. The 

 results of these studies (Special Scientific Report: Fisheries Nos. 71, 91, and 

 130) indicated that the most promising line of attack on the immediate practical 

 problem--discovering a means of attracting tuna to within reach of a fishini? ves- 

 sel at sea--wa3 in the field of chemo-reception. It was found that the tuna in 

 the pond responded positively and often violently to extracts of tuna and other 

 fish flesh, viscera, etc. 



In June 1953 another contract (14-19-008-2126) was negotiated to pursue 

 these studies further. The testing of materials in the pond was to be continued. 

 Sea tests were to be conducted to observe the response of "wild" tuna not only to 

 extracts, but also to visual stimuli such as lures of various sizes, shapes, and 

 colors, used either alone or in conjunction with extracts. 



This report includes the results of this third study. Although the work 

 was conducted mostly from June to October 1953, sea tests extending from January 

 29 to November 13, 1953, are included, 



ACKNOVVLEDGMENTS 



As in past years, troll fishing to stock the ponds with tuna was conduc- 

 ted under the skillful direction of Mr. Lester Zukeran, skipper of the University 

 of Hawaii research vessel Sal pa . Mr. Eugene Nakamxira and Mr. Royden Ikeda, stu- 

 dents, assisted in both fishing and sea testing with this vessel. Mr. Charles 

 Nakamoto, assistant to the Hawaii Marine Laboratory, again was responsible for the 

 feeding and care of the captive fish. 



We are again indebted to Mr. Raoul Pantaleoni of E. I. Du Pont de Nemours 

 & Company, to Dr. Ernst T. Theimer of van Ameringen-Haebler, Inc., to Mr. George 

 H. Zirkel of P. R. Dreyer, Inc., and to Mr. R. E. Horsey of Sindar Corporation for 

 supplying many of the chemical compounds which were tested in the pond. In parti- 

 cular, we are grateful to Mr. Fritz Jermann of Hawaiian Tuna Packers Ltd. for pre- 

 paring most of the extracts vjhich were tested at sea. 



The staff of the Pacific Oceanic Fishery Investigations cooperated to 

 the utmost. Special thanks are due Mr. 0. E. Sette, Director, and Mr. D. L. McKer- 

 nan and Dr. iV. F. Royce for advice and assistance. Not only were the two research 

 ships Charles H. Gilbert and Hugh M. Smith made available for sea testing, but 

 also many of the staff members conducted or assisted in conducting the sea tests, 

 including D. L. McKernan, J. Slipp, D. Yaraashita, H. Mann, and T. Otsu. 



The senior author, who directed the investigation, assumes responsibility 

 for the compilation of this report and for the analysis and interpretation of the 

 data which are included. Most of the sea testing was undertaken by the second 

 author; most of the pond testing was undertaken by the third author. 



