USS LAFFEY 



JULY 1946 



I67°-I68°E LONG 



Figure 14. --Vertical temperature section at 167 -168 E. 

 longitude. Adapted from Robinson (1952). Isotherms are 

 in Fahrenheit. 



There is also some indication from the pre- and post-war fishing in the mothership 

 area of long term cyclic or epochal fluctuations in abundance. Nakamura (1943) reported 

 comnnercial catches (tunas and spearfishes) of 6.05 per 100 hooks between and 5 N. latitude 

 and 1.70 north of 10 N. during pre-war years. If these data are comparable with the post-war 

 mothership data, the indications are that the location of greatest abundance was the same then as 

 now, but that the pre-war level of abundance was higher. In addition to the general figures on 

 the commercial catch, a considerable amount of exploratory fishing was carried out by the 

 Japanese in the area. Watanabe (1940) reported 3.4 yellowfin tuna per 100 hooks at 1 20'N. , 

 172 30'E. on May 16, 1940. Uehara (1941) reported catches of 10 to 14 tunas and spearfishes 

 per 100 hooks for four stations from 1 1 ' to 1 11' north of the Equator between 131 and 134 E. 

 longitude during May 1941. Dcebe (1942) reported slightly higher catches in this same general 

 longitude but south of the Equator during July 1941. Ikebe (1941) reported on five stations between 

 the Equator and 5 N. lying between 146 and 169 E. longitude with catches of yellowfin tuna of 6, 

 5, 23, 19, and 15 per 100 hooks. 



28 



