100° w 



80° W 



60° W 45° W 30° W 



20° E 



30° N 



20° N 



10° N 



30° S 



30° N 



5° N 

 0° 



20° S 



30° S 



100° W 



15° W 



20° E 



Figure 1. — Areas used in this study. 



Table 1. --Summary of catch and effort in the Japanese Atlantic longline fishery, 1956-64 



[Estimates, adjusted for whole fleet on basis of sample in each year. 

 Symbol represents 500 or fewer fish] 



1 Includes striped marlin. 



2 Includes spearfish and sailfish. 



Note: This table embodies certain corrections of Wise and Le Guen's (in press) table 1. 



The distribution of fishing effort in each of 

 the areas for 1956 through 1964 is shown in 

 table 2. (The Gulf of Mexico area, CM, was 

 included in the Florida area in the previous 

 analysis. It is north oflat. 20<> N.,westof long. 

 80° W., plus the ocean area between long. 90° 

 and 100O W., north of lat. 15° N.) The greatest 

 changes in effort between 1963 and 1964 were 



in the Guianas, North Oceanic (West), Bahia, 

 and Rio de Janeiro areas. All these areas in 

 which fishing effort increased markedly arem 

 the western Atlantic; three of them are among 

 the best areas for albacore (table 4). 



The mean catch rates for yellowfin tuna for 

 the 11 areas, 1956-64, are shown in table 3. 

 The mean rate was determined by adding the 



