FISHERY BULLETIN: VOL. 69, NO. 3 



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Figure 2. — Distribution of juvenile sl<ipjack tuna (dots) by quarters of the year in the South Pacific. The 

 shadings show the billfish sampling area. 



fishes. Only small number.s were taken between 

 January and June and between October and 

 December. In 1964 and 1965 the summer 

 peak in abundance was not so high; however, 

 juveniles were more numerous in other months. 

 The apparent abundance of juveniles was 

 highest in 1964 when an average of 21.3 ju- 

 veniles per 100 billfishes was taken. In 1965, 

 an average of 19.1 juveniles was taken, and in 

 1963 the average was 12.4. 



South Pacific 



To examine the seasonal apparent abundance 

 of juvenile skipjack tuna in the South Pacific, 

 the area north of lat 10° S was considered sep- 

 arately from the area between lat 10° and 20° S 

 (Figure 4). Because the coverage was poor in 



any one year, the data for all years were 

 combined. 



Juvenile skipjack tuna were taken through- 

 out the year north of lat 10° S. Peaks in the 

 apparent abundance were evident in April and 

 October. Larvae have been taken throughout 

 the year in the equatorial waters (lat 10° N to 

 10° S) of the central Pacific (Matsumoto, 1966). 

 They were most numerous between April and 

 July. Thus, the apparent abundance of the 

 juveniles differs somewhat from that of the lar- 

 vae in that a peak was absent in larval abundance 

 in the latter half of the year. The diff"erence 

 in apparent abundance between the larvae and 

 juveniles may not be real. The small number 

 of stomachs collected in the latter half of the 

 year may not have been adequate to reveal the 

 true abundance of juveniles. 



548 



