fairly good between 150 E. and l60 E. , but no concentrated fishing 

 grounds had developed west of 150 E. In 1950— the trends were in 

 good agreement with the chart presented here. 



Table 1. --Comparison of prewar and postwar catch rates 



The "postwar" figures include the prewar data 



Table 1 is a comparison with prewar data (from Nankai Regional 

 Fisheries Research Laboratory Report No. 1). Except for the areawest 

 of 150 E. longitude, in general the fishing conditions appear to be inferior 

 to those of the prewar period, but the reasons for this are not cleaur. 



The distribution of catch rates appears to show a gap between 

 150 E, and l60 E. According to UdaZ', judging from the sizes of the 

 fish there are three different age groups in this area, each following a 

 different migratory path but all nnigrating in a clockwise direction, 

 Nakamura—' pointed out that at the beginning of the fishing season 

 (November) there is one group appearing in the area centered at 150 E. 

 and another group in the area centered at 165 E. ; in December isolated 

 fishing grounds are formed in the Kinan Sea Area, cuid a tendency can 

 be detected for part of the group in the vicinity of 150 E. to appear to 

 move toward the southeast, but aside from these observations it is not 

 possible to show any differences between the groups on the basis of catch 

 rates. 



The sizes of albacore taken in the North Pacific show local differ- 

 ences in the east-west direction and also in the north-south direction. 

 Table 2 shows these local differences. 



3/ 



— Nankai Regional Fisheries Research Laboratory, High Seas 



Resources Section, Summary Report of Investigations, 1952, Chart No. 23, 



4/ 



— Uda, Michitaka and Eimatsu Tokunaga, Bull. Jap. Soc. Sci. 



Fish., Vol. 5, No. 5, pp. 295-300, 1937. 



5/ 



— Nakamura, Hiroshi. Nankai Regional Fisheries Research 



Laboratory Report No. 1, 1951. 



14 



