YOSHIDA: AMERICAN SAMOA LONGLINE FISHERY 



qI I I I I '' I I I I I I I I I I I I I I I I I I I I I I ]] I II Ill I I I I I I I I I I I I I I I ill 



1963 1964 1965 1966 1967 1968 1969 1970 1971 



Figure 5.-Monthly mean albacore CPUE and effort, 1963-71. 



z 



O 25 



o 

 a: 



o 



I 



5 10 15 20 25 30 35 40 45 50 55 



ESTIMATED TOTAL ANNUAL FISHING EFFORT (MILLIONS OF HOOKS) 



Figure 6.-Relatlon between total catch of albacore and total 

 effort, 1963-71. 



the fishery taken as a whole. It is of interest to 

 compare the conditions north and south of lat. 

 20°S, especially since the geographic boundaries of 

 the fishery have been expanding over the years. 

 That is, it would be useful to see how the CPUE in 

 the older fishing grounds north of lat. 20°S com- 

 pares with that in the more recently exploited 

 grounds south of lat. 20°S. The annual mean 

 CPUE was computed for the area north of lat. 

 20°S, which represents the older fishing ground, 

 and the area south of lat. 20°S, which represents 

 the newer grounds (Figure 8). This analysis must 

 be viewed with some caution, however, since total 

 effort expended south of lat. 20°S is less than that 

 expended in the north. Southern waters are fished 

 heavily only in certain quarters of the year and 

 these are the quarters when good catch rates are 

 obtained. The mean catch rates in the southern 

 waters therefore, may be overly weighted by the 

 catch rates obtained in these quarters. However, 

 the mean annual CPUE is higher in the newer 

 grounds than in the old. The mean annual CPUE's 



751 



