April. However, because of the paucity of data for these two months, we cannot determine 

 whether this sort of change represents a normal condition or whether there is a gradual decline 

 in the catch rates from February through April. Spearfishes are generally scarce, but a catch 

 rate of 1. 5 in October shows that there is a possibility of taking certain amounts of thenn. 



0,0 

 If the foregoing is compared with 150 to 160 E. , 



(1) The patterns of increase and decrease for black tuna and yellowfin in the two sea 

 areas are almost same. 



(2) Bigeye catch rates are generally higher in this sea area, and the seasonal trends 

 of increase and decrease agree well. 



(3) Albacore catch rates are generally higher in this sea area, and the peeik fishing 

 season is about 1 nnonth earlier. 



(4) The spearfish catch rates are generally lower in this sea area, but the seasonal 

 changes in the fishing conditions are in general agreement. 



These factors show a very close relationship between the two sea areas. 



The most important spearfishes are striped marlin and broadbill, with some black 

 marlin mixed in. The following table shows seasonal changes in the proportions of striped 

 marlin (including black marlin) aind broadbill. 



Table 93. --Coniiposition of the spearfish catch 

 (30° to 35° N. , 160° to 170° E. ) 



On the whole striped marlin make up 60 percent and broadbill 40 percent of the total. 

 In October striped marlin are overwhelmingly predonninant, but they gradually decline thereafter. 

 On the contrary, the broadbill gradually increase and approximately equal the striped marlin in 

 December, and they sire in the majority in March. This is roughly the same situation that was 

 seen in the area of 150 to 160 E. (see table 89). 



There are many deficiencies in the data on sharks, so it is not clear what chjmges 

 take place in the shark fishing. 



As the foregoing shows, this sea area is an extrennely good albacore fishing ground. 

 The fishing season is completely confined to the winter, with the pealc of the season in January. 

 Bigeye tuna are next in innportance to albacore, and they are teiken most abundantly in November 



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