CD 

 UJ 



^^ 

 LU CD 



tr. 



UJ 



03 



P 



Lu tn 

 H -I 



op 



UJ H 



200 



150 



100 



50 







80 



60 



40 



20 







140° 



TOKYO 

 2200 M. 



160" 



180' 



160° 



HONOLULU 

 1200 M. 



140° 



120° 



SAN DIEGO 

 2000 M. . 



T 1 ' 



, .: - *'' 



140° 



160° 



180° 



160° 



140° 



120° 



LONGITUDE W. 



Figure 19. Variation in Size of Yellowfin Along the 

 Equator . The commercial venture stressed the importance of 

 increasing our knowledge of the distribution of tuna with respect 

 to size. The upper panel shows the change in size of the yellow=- 

 fin along a 6,000-mile stretch of the equatorial Pacific. To the 

 west of 180° each point represents a sample taken by POFI obser- 

 vers while on board Japanese motherships, while to the east of 

 180°, the measurements are from POFI catches. The size appear s 

 to increase in steps rather than in a steady progression and there 

 is an indication that the tuna are smaller east of 140° Wo 



The lower panel shows the percentage of fish that 

 weighed less than 150 pounds. Since a size of about 150 pounds 

 is the upper limit for having nnost of the catch accepted under the 

 "light meat" canning label, it is of interest to note that most of 

 the yellowfin caught west of 140° Wo longitude have been under 

 150 pounds. 



20 



