also larger populatiuiis of the smaller and youiig-er tish, that 

 now are not taken at all. 



Speaking at the Governor's Conference on Science and 

 Technology, State of Hawaii, in January 1965, John C. Marr. 

 BC'F Area Director. Hawaii, said, "It has been estimated 

 that these resources could yield an annual catch of jjerhaps 

 200.000 tons. We know that the resources exist, we know 

 the general — but not the specific — details of their geograph- 

 ical distribution, we know that they generally occur beneath 

 the surface, and we suspect that they occur in schools. We 

 do not know where major concentrations occur, if such 

 exist, we do not know their depth distribution and how this 

 may vary, and we do not know certainly that the fish occur 

 in .schools." 



As this report has shown, much of the work of our 

 Laboratory is shaped toward solving the problems in meas- 

 uring, locating, and harvesting this great hidden re.source. 



Tunas in the Indian Ocean 



.■\lthough it covers one-seventh of the globe, until recently 

 the Indian Ocean has been one of the least explored areas 

 on earth. Our Laboratory has planned and implemented 

 that portion of the U. S. contribution to the great Inter- 

 national Indian Ocean Expedition that is concerned with 

 fishery biology. Scientists, technicians, and crew members 

 from the Laboratory participated in .several of the cruises 

 of the U. S. biological research vessel Anton Bnittti. In the 

 course of these cruises, our Laboratory collected informa- 

 tion on the distribution and abundance of tunas; when 

 examined in conjunction with data from the Japanese tuna 

 catches there, this information should Ijring a new uiuier- 

 standing of the food resources of the Indian Ocean, which 

 is bordered by teeming nations whose need of new supplies 

 of animal protein is jiressing. 



HfTort in the Indian Ocean was devoted to carrying out a 

 wide north-south survey to determine the distributional 



limits of the \arious species and to gather environmental 

 data. 



Richard S. Shomura, who is analyzing the information 

 on the high-sea resources of the Indian Ocean, found a most 

 distinct separation of water types along the transect at 

 long. 70 E. (fig. 18). Arabian Sea Water with high temper- 

 atures and high salinities in the surface layers extended 

 south to about lat. 10" N. In the central Indian Ocean, 

 equatorial water was found from lat. 10' N. to about lat. 

 11 S. From there to lat. 37- S., the southernmost station. 

 South Indian Ocean Central Water prevailed. The other 

 three transects showed more complex relations. 



All of the catches of albacore tuna were made south of 

 lat. 8 S. in waters that seem to be of the South Indian 

 Ocean Central type. The albacore were mostly large. 



The yellowfin tuna were taken widely in the central and 

 western Indian Ocean. In the central portion, they were 

 taken from'about lat. 10 N. to about lat. .30 S. They ap- 

 peared to be associated with both the equatorial water and 

 South Indian Ocean Central Water. They averaged 76 

 pounds. 



Bigeye tuna were caught from lat. 10 N. to the southern- 

 most station, but a gap appeared to exist between lat. 12 S. 

 and 40 S. They averaged 100 pounds. 



The data from the Indian Ocean cruises will be added to 

 the tremendous store from the Japanese fisheries in a co- 

 operative study that will be carried out with scientists from 

 the Nankai Regional Fisheries Research Laboratory. The 

 study will examine the relation of distribution and abun- 

 dance to oceanograi)hic features. 



One of the aims of the biological program in the Indian 

 Ocean was to gather information on creatures of the sea 

 other than food fishes. Included were the zooplankton — those 

 little drifting marine animals that make up much of the 

 food of fishes. These data are still being studied. From the 

 [ireliminary studies have come some interesting results. 



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