been doneo In actual operations the fishermen are by no means 

 unconcerned with these problems o They do adjust the float-lines 

 in various ways, however, this is not based on any reliable 

 theoretical foundation, but is merely a sort of probingo 



Assuming that the lengths of the branch lines and the float 

 lines have been settled, the next problem is their number^ The 

 number of branches is generally considered in relation to their 

 length find that of the main line„ Increasing the number of branch 

 lines is advantageous in that it means a like increase in the number 

 of hooks employed in each operationo Hov/everj the interval between 

 branch lines naturally has to be determined by considerations of 

 convenience in handling the gearo Furthermore, for reasons of 

 economy one hank of line is cut into four or five pieces in such a 

 way that none of it will be wastedo The number of branch lines is 

 also related to the weight of the gear as a whole, and so to the 

 problem of the so-called "stretch" of the line, lYhen the branch 

 lines axe few, it gives rise to a tendency for the line to stretch 

 and the danger of the line's breaking increaseso If the branch 

 lines are many, the whole gear becomes heavy and hard to handle, 

 and also occasions arise where a large number of fish are taken 

 on one part of the line which consequently breaks or simply sinkso 



When various factors of this sort are taken into consideration, 

 determining the construction of the lines is very difficulto Among 

 the gear in use at present, except for albacore lines, most of the 

 lines have either five or six brancheso This type of gear is the 

 result of many years of experience in the light of the various con- 

 ditions set forth in the foregoingo Therefore, it may well be that 

 this construction is the best possible, but there is as yet no 

 scientific evidence that this is the case. The longline construc- 

 tion most suitable for each sea area should be established upon a 

 scientific basis through the consideration of oceanographic condi- 

 tions, ease of operation, and economic problems connected with 

 materials and baito 



The problem of bait 



In the case of the skipjack fishery, bait is a very great 

 problem, in some instances a limiting factor on the development of 

 the fisheryo As everyone knows, this is because live bait is an 

 absolute requirement„ In the case of the tuna longline fishery 

 the bait does not have to be aliveo Frozen, iced, or in some cases 

 even salted bait may be used.. This fact may be considered an 

 extraordinarily strong point of this fisheiyo 



Of course fresh bait is preferable and is superior as bait. 

 This superiority may, of course, lie to some extent in the fact that 

 tuna bite better on fresh bait, but of even greater importance is 

 the fact that such bait "keeps" wello This means that the bait 

 does not fall off the hook easilyo According to the results 



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