Fjitai: I vyir:h to 3r.pr5s;n my deop appreciation to you for s. crifioing your -"aluable 

 time to asseiQble h3re» You have already been informed as to the purpose of to- 

 night's meeting so I believe it is unnecessary for me to rev.ew it in detail. How- 

 ever, as there are a few persons present tonight who are not acquainted with the 

 objective of this gathering, I would like to say u few ?yords .''or their benefit. 



There exist an extremely large niunber of marine fish wh )se spawning grounds 

 have not yet been determined. In fact, I feel I do not exagg3rate when I say that 

 almost none have been delineated. Furthermore, notliing has been confirmed with 

 respect to the skipjack and tuna, which are of great economic importance, especially 

 to the Japanese fishing industry. It ia to be regretted that so little is known 

 about the spawning grounds, spawning habits, and development of these fish. This 

 difficult problem, however, is not limited to Japan alone - it is universal in na- 

 ture. In Japan, such persons as the lete Kamakichi Kishinouye worked assiduously 

 in collecting skipjack and tuna juveniles. Technician Marukawa, who is present to- 

 night, and others have also been deeply concerned with this problem. They are now 

 conducting a careful investigation but results are as yet unknown. Scientists from 

 various foreign countries have also worked hard on this subject, but despite all 

 this, their situation remains the same as that in Japan in that no conspicuous con- 

 tributions have been made towards its solution. Due to these circumstances, each 

 Pacific Science Congress usually takes up the question of skipjack and tuna spawn- 

 ing and submits measures to undertake its solution through joint action of various 

 countries. Although many helpful discoveries and studies pertaining to fisheries 

 are reported on at these conferences, held at intervals of three or four years, the 

 problem concerning the spawning habits of skipjack and tuna remains the same as 

 when it was first presented more than ten years ago. No new facts have yet been 

 ascertained. 



However, in generalizing on the common efforts and observations of fishermen 

 and ichthyologists, the spawning grounds of skipjack and tuna are, to all appear- 

 ances, in tropic seas. For example, information such as the capture of skipjack 

 ready to spawn or collection of juveniles believed to be those of skipjack is 

 usually received from the tropics. 



Fortunately, our country today has extensive tropical possessions. There is 

 also the Tropical Biological Station sponsored by the Japan Society for the Promo- 

 tion of Science. It has been my wish for many years to gather various Japanese 

 scientists in an attempt to solve this important problem of spawning, using this 

 Station as a ba^e for operations. The opportunity to realize this desire was made 

 possible through the positive support given by the Pacific Society, I have, there- 

 fore, requested the presence here tonight of you authorities on the tropics and 

 those of you who are actually active in the area, to hold a discussion on skipjack 

 and tuna with the main emphasis being placed on spawning. With this symposium as a 

 foundation, I thought we could take up the formulation of a definite plan as to how 

 this undertaking should be started and how it should be effected. Your presence 

 here despite the pressure of other duties is gratifying indeed., Since we do not 

 have too much time, this will serve as an introduction. Now we would like to hear 

 your opinions. I would like first to call upon Mr, Marukawa. 



Marukawa ; In Japan, research on skipjack and tuna was conducted qhiefly by Dr.. 

 Kishinouye. Although there are Mr. Kit,ano*s report and a few others in taxonomy, I 

 believe that Dr. Kishinouye was the first to make a scientific study of these fish^ 

 The question as to the location of the spawning grounds of skipjack and tuna still 

 is definitely a mystery; I can only conceive it to be in the South Seas, I believe 

 that research soon to begin at the Palau Tropical Biological Station in the South 

 Seas is most ideal. At this point, I will go back into the past for information 



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