There are remarkably few data for the area from 160 to 170 E. , so that it is 

 impossible to compjire it with the areas farther to the west. For the whole region the areas 

 centered on 150 E. longitude show the highest catch rates. The majority of the catch is com- 

 posed of yellowfin in all of the areas. Except for the extreme western portion, there is little 

 discernible variation in the yellowfin catch rates. In the case of the bigeye tuna, it appears 

 that there is a tendency for the catch rates to increase as one goes eastward. The catch rate for 

 spearfishes is highest in the vicinity of the area of 140 to 150 E. longitude, that is west of the 

 Caroline Islands. The jilbacore was scarce everywhere, but was markedly more abundcint in the 

 waters of the Caroline Islands than in the other areas. 



Table 32 is based on data collected in the past 2ind it completely ignores fluctuations 

 from year to year in the fishing conditions, seasonal changes in catch rates, differences in the 

 longitude of the points surveyed, cind changes in the catch due to the construction of the fishing 

 gear. Of these variables, the changes from year to yesir in the fishing conditions cannot be 

 discussed with the data we have at our disposal. Nor do we have data which will enable us to 

 make any judgments concerning the changes in fishing conditions brought about by differences 

 in the construction of the gear. The fact that there Jire violent fluctuations in fishing conditions 

 due to latitude was shown in table 31 and it is naturally to be imagined that there will be conspic- 

 uous changes in the fishing situation accompanying the chjmge of seasons. 



In order to see the effect of latitude on the differences shown in table 32, the following 

 table presents the same east-west divisions further divided by the line of 5 N. latitude into 

 northern and southern portions. 



Table 33. --Fishing conditions in divisions of 10 of 

 longitude on either side of the line of 5 

 N. latitude (southern part of former South 

 Seas Mandate) 



Note: The catch rates are combined for tunas and spearfishes. 



Leaving out of consider ation the area east of 160 E. longitude because of the lack of data, the 

 highest catch rates south of 5 N. latitude were in the area between 140° and 150° E. longitude. 

 North of 5 N. latitude the highest catch rates were between 150 and 160 E. Catch rates were 

 low between 130 and 140 E. both north and south of 5° N. 



In order to see how the data in table 32 are affected by seasonal chcinges in the fishing 

 conditions, the following table has been made using the same areas as table 32 and dividing the 

 data according to whether they represent the season of southwesterly or northeasterly winds. 

 The area between 160 and 170 E. , for which little data is available, has been eliminated from 

 this table. 



69 



