event, the carcasses were not fotindo The fifth yellowfin died on 

 September 16, 1952o An additional yellowfin (10 pounds) was placed 

 in the pond on October 28, but it died 5 days l^ter without starting to 

 feedo 



Of 15 tunny (1 to l^l/Z pounds) introduced to Pond NOo 5 

 between July 25 and August 25, 1952, 13 started to feed and became 

 established, despite the fact that several were tagged fthe tags later 

 became detached)o The remaining 2, which were tagged„ died within 

 2 days. The 13 established tunny were present until October 16, 1952, 

 following which 6 died 3 betv^een October 16 and 20^ 2 between 

 October 21 and 27, and 1 between October 30 and 31, The remaining 

 population of 7 fish was maintained until December 5^ 1952, when 1 

 more diedo The 6 remaining fish persisted until January l6j 1953o 

 One died on January 16^ 2 between January 17 and 20, and 1 between 

 January 22 and 23^ 1953„ The 2 tunny which remained survived the 

 winter and spring and are still living at the time of writing, more theia 

 1 year after they were introducedo During this period they have in- 

 creased in weight from about 1 to 4 pounds o 



The reason for the mortalities of tunny reported above is 

 uncertaino The temperature and chlorinity in Pond NOo 5 are shown 

 in figure U The six destths in October coincided with the beginning of 

 a steep downward trend in temperature and a slight downward trend 

 in chlorinity, both of which were associated with the incidence of 

 rainy weathero However, the four deaths in Janu:jry cannot be related 

 to changes in temperature and salinityo Moreover, the two remaining 

 fish survived through February and Marchp when considerable rainy 

 weather was encountered and when the chlorinity in the pond reached 

 a low for the year (15o834 p„pomo on March 11, J.953)o 



Although comparable temperature aind chlorinity data for 

 the previous year (when all fish died following wet stormy weather) 

 are not available, in generalp the winter weather in 1952-'5 3 was nnuch 

 better than in 1951-52, with markedly fewer "kona" storms (south to 

 southeast winds with rain)o This may have contributed to the success 

 in maintaining two of the fish throughout the winter „ During the one 

 bad storm of the 1952-53 season on October 13 and 14, mortality may 

 have been reduced by tying the Salpa to the dock near the outer gates 

 and flushing fresh water from the pond with the wash of the propeller„ 



In both the tank and pond the tunas were fed during the 

 late afternoon of Tuesday;, Thursday, Saturday, and occasionally 

 Sunday, of each weeko Their food consisted mostly of tuna flesh 



