Table 12. --Abundance of bird flocks in relation to distance fronn lajid— 



1/ 



— Includes incidental as well as systematic scouting results. 



Live bait fishing by itself was never a major objective of the cruises. It was carried on 

 in conjunction with tests of tuna attractants, which were usually performed in the calm leeward 

 waters where the tuna were easy to observe. On scouting runs live bait was available only a 

 small part of the time and it was used to sample as many schools as possible. 



Our relative success in fishing schools may be judged only by the percentage of schools 

 from which we caught fish. In no instance was our catch indicative of what might have been taken 

 by a comnnercial fisherman, because we regularly stopped fishing as soon as a sample of the 

 school was obtained. Of a total of 83 schools chummed, 36 or 43 percent were successfully 

 fished (table 14). The failures were those which did not respond at all or which did not approach 

 the vessel atfter rising to the surface for the chum. No consideration was given the number of 

 passes made in the school or the number of fish taken. There were some variations in the per- 

 centage of success during the various cruises, but the numbers are so snnall that the differences 

 are not statistically significant. 



Our sampling bore out what is common knowledge among the fishermen- -that the skipjack 

 school by sizes. The length and weight frequencies of skipjack taken are given in table 15. Many 

 of our samples are too small to be indicative of the range of sizes in the school, but in some of 

 the schools of small fish from which adequate ssmiples were obtained the range was as narrow as 

 fronn 2-3/4 to 3-3/4 pounds (on April 28 and July 5). Other schools were more mixed, the one 

 fished on June 8 ranging from about 2-1/4 to 9-1/2 pounds and another, on June 9, from about 

 1-3/4 to 12 pounds. The larger fish were always by thennselves, and with an average size of 

 about 20 pounds they commonly included a range of 10 or 12 pounds. Brock (1954) also found 

 skipjack to school by sizes, and he reported the mean range in length of fish in a school (based 

 on 120 school samples taken in 1950) to be 11.3 cm. compared to the range of 47 cm. for fish 

 in the landings as a whole. 



21 



