PART III 

 OBSERVATIONS ON THE REACTION OF mi A ID ARTIFICIAL LIGHlV 



by- 

 Sidney Co Hsiao 

 Associate Professor of Zoology- 

 University of Hawaii 



INTRODUCTION 



The jj'esponse of fish to visual stimuli -was studied as early as 

 1880 by Kuhne and Sewall, Since that early date^ a great deal of 

 information has been accumulated on the structure and function of 

 the piscian -visual organ^ and on the question of color vision in fishj 

 a subject of discussion and dispute amoung physiologists o The liter- 

 ature on color vision in fishes has been critically reviewed by 

 Warner (1931) » Wall's (19U2) monograph dealing with the adaptive 

 radiation of the vertebrate eye brings the literature review up to 

 19l;lo No further re-view has appeared over the past 10 years. 

 Nearly all the experiments on piscian vision^ both achromatic and 

 chromatiCj were doie on favorable laboratory specimens „ which were 

 hardy and of suitable size for indoor tanks „ As far as can be 

 ascertained^, no experimental work on the physiology of vision in 

 tuna has been reported^ none is included in a recently published 

 bibliography on the biology of the Pacific species (Shimada 19^1) » 

 Field observations made by amateurs and professional fishermen have 

 been accumulated for some time^ but conclusions based on them are 

 badly in need of verificationo 



It is the purpose of these studies to discover the pattern of 

 reaction of tuna, established in captivity,, to different quantities 

 and qualities of light stimuli » The former is concerned with tb& 

 intensity and duration of light stimulation, and the latter with the 

 frequencies of the light usedj that is^ the different portions of 

 the -visible spectrum -Jrhich are involvedo The success of Tester 

 (19^2) in capturing several species of Pacific tuna^ transporting 

 them to shore, and keeping them alive in the confined space of an 

 outdoor pond and tankj makes it possible to experiment with these 

 oceanic species under controlled conditionSo It was hoped that 

 attraction or repulsion stimuli would be discovered which might have 

 some use in explaining the behavior of tuna in their natural habitat, 

 and perhaps in suggesting new or improved methods of captureo 



The work was undertaken during the summer of 19^1 at the Hawaii 

 Marine Laboratory under the general direction of DTo Ao Lo Tester, 

 University of Hawaiij, whose assistance iff gratefully acknowledgedo 



^/"contribution Noo 2U of the Hawaii Marine Laboratory, University 

 ~ of Hawaii J Honoluluj To Ho 



36 



