material collected in the past and now 

 being taken could be profitably used to 

 gain some understanding of the variations 

 that occur in the seasonal distribution and 

 availability of the albacore. 



Little is known about tuna behavior. 

 Personnel at the Bureau's Honolulu labora- 

 tory, under the direction of Vernon E. 

 Brock and his distinguished predecessors, 

 has recognized the need for such knowledge 

 and considers it one of the basic require- 

 ments for increasing fishing efficiency. 

 Scientists have embarked on a program to 

 learn about the behavior of tuna in 

 Hawaiian waters. They believe that the 

 elucidation of patterns of behavior can 

 help make existing fishing methods more 

 efficient and may also help in suggesting 

 more effective means of harvesting. There 

 is need for similar studies in the. Eastern 

 Pacific. Live bait fishermen encounter all 

 types of schools ; so do albacore jig-boat 

 fishermen, and so do purse seine fishermen* 

 Some schools bite well, others bite poorly, 

 and still others do not bite at all. 

 Schools are often too scattered or too fast 

 to catch with either a purse seine or live 

 bait. Purse seiners find some schools are 

 accompanied by too many porpoise. Since 

 fishermen have to stop fishing at nightfall, 

 schools they are working then are often 

 lost by morning. Do these schools maintain 

 themselves during the night? Can they be 

 followed if they do? If fish are biting 

 well at night, can they be expected to bite 

 the next morning? When can nonbiting 

 schools be expected to become biting 

 schools? When are scattered schools likely 

 to become compact? These are only a few of 

 the questions that fishermen would like 

 answered. They point out that studies of 

 tuna behavior would be useful to the fish- 

 ermen. 



More knowledge of the behavior of the 

 bait species while in captivity aboard tuna 

 boats might well contribute to reducing 

 time spent on fishing trips. Fishermen 

 have varied success in keeping bait fishes 

 alive, and since a considerable amount of 

 time is used to catch these fishes and to 

 run to and from baiting and tuna fishing 

 areas, studies of optimum crowding, whether 

 and what bait fishes should be fed, temper- 

 ature requirements, and other features could 

 contribute to minimizing the duration of 

 fishing trips. 



THE ROLE OF THti BUREAU IN REDUCING 

 FISHING TEE 



Our present thinking leads us to 

 believe that the Bureau can make its maxi- 

 mum contribution to the fishing industry 

 through studies of oceanography, biology, 

 fishing strategy, and by collecting and 

 disseminating current information consid- 

 ered useful to the fishing industry. Let 

 us examine some of the more promising 

 possibilities. 



Oceanography 



The Scripps Institution of Oceanography 

 of the University of California is, under a 

 three year contract with the Bureau, study- 

 ing the relationship between ocean features 

 and tuna availability. This work began in 

 late 1957 and the contract will expire in 

 June 19^0. The University, under 

 Dr. Maurice Blackburn's guidance, is making 

 good progress in these studies. We have 

 pointed out the contribution that oceanog- 

 raphy is potentially capable of making and 

 believe that this type of investigation 

 should continue. 



The Bureau' s Stanford Biological Lab- 

 oratory is engaged in a study to determine 

 on an ocean-wide scale the relationship of 

 medium and long term (more than one month) 

 changes in environmental conditions to 

 medium and long term fluctuations of fish 

 stocks in the Pacific Ocean. Dr. C. E. 

 Sette, veteran Bureau scientist, has a 

 small but select team examining air cir- 

 culation indices, sea level variations 

 and mean sea surface distribution for 

 the past 30 years. We believe the results 

 of these investigations will be most use- 

 ful to the scientists studying oceanography 

 in relation to tuna availability and that 

 they will eventually contribute materially 

 to tuna forecasting. 



The Bureau recently assumed responsi- 

 bility for a project initiated by the 

 American Tuna Boat Association to analyze 

 and plot existing data on soundings in the 

 Eastern Pacific which have been made over 

 the years from research craft of Scripps 

 Institution and other vessels. It is 

 known that yellowfin tuna are frequently 

 found to be abundant around sea mounts. 

 The recent accidental discovery of Shimada 

 or Hurricane Bank and the ensuing large 



57 



