Figure 12.— Relative abundance (number of larvae per 1,000 m^ of water strained at the surface) of Auxis in May-October, based 

 on plankton collections made in the eastern tropical Pacific. Dashed lines enclose area under investigation by Inter-American 

 Tropical Tuna Commission in 1952-59; black dots indicate positions of plankton hauls vrith zero catches. (Klawe 1963.) 



Table 9. — Average number of Auxu larvae caught per hour during 

 different months off Cape Blanco, Costa Kica, with a 1 m (silk or 

 nylon) net towed at 1.0 m/x (Klawe 196.3). 



From the central Pacific, there is evidence that Auxis 

 spawn not only in waters around the Hawaiian Islands 

 but also to the west and south of these islands. The pres- 



ence of small larvae of 3 mm or less in plankton samples 

 indicated that spawning probably occurred in these 

 waters just a few days prior to sampling (Table 10) 

 (Matsumoto 1958; Strasburg 1959). Further evidence of 

 spawning has been reported by Yoshida and Nakamura 

 (1965), who observed that among the fish landed from 

 schools of A. t hazard and A. rochei fished by pole and 

 line off Kaena Point, Oahu, milt was flowing from the 

 vent of males of both species. The females, however, 

 showed no signs of free-flowing eggs even after pressure 

 was applied to the abdomen externally. Subsequent ex- 

 amination revealed that the females had ovaries that 

 were flaccid, translucent, and grayish such as those 

 usually seen in spent females of yellowfin tuna (June 

 1953). 



17 



