Compared with the waters between 140 E. and 150 E. the fish 

 are generally 1.2 to 1.7 times larger. At 30 N. to 32 N. , 150 E. to 

 l60°E., the size of the fish is greater than in any sea area to the east 

 or west, marking a break in the general trend for the size of the fish 

 to increase to the eastward. It is, however, impossible to tell whether 

 this condition always obtains without accumulating more data. 



Table 13a and b presents the relationship between the surface 

 water temperature and the catch rates between l60 E, and 170 E. 



Table 13a. --Surface temperature and catch rate, December, 30 N. - 

 35°N. , 160°E. -170°E. 



Average water tennperature where fish were taken, 18.6 C. 



Table 13b. --Surface temperature and catch rate, December, 35 N, 

 40°N. , 160°E.-170°E. 



Average water tennperature where fish were taken, 17.8 C. 



It can be seen from the table that between 30 N. and 35 N. the 

 o o 



mode is between 18 and 19 C. and catch rates are approximately 3.0 



or above within the rajige of 17 C. to 21 C. Consequently, it will be 



profitable to avoid waters having temperatures below 17 C. or above 



21 C. in operating in this area. 



Between 35 N. and 40 N. , the mode is between 17 C. and 19 C. 

 but fairly good catch rates are seen at the other water temperatures 

 represented. 



49 



