HIDA: FOOD OF TUNAS AND DOLPHINS 



Table 1. — Frequency occurrence of organisms in the stomachs of 268 

 skipjack tuna, 44 bigeye tuna, 45 yellowfin tuna, and 9 dolphin (2 com- 

 mon and 7 little) examined from cruise 116 of the Charles H. Gilbert. 



contents of 13.1 9f of the skipjack tuna and 

 45.4% of the bigeye tuna examined was of par- 

 ticular interest. Of the invertebrates, squids 

 were most frequently found in the contents. 

 Many of the stomachs examined were empty. 



This study revealed that only a few varieties 

 of organisms were eaten in the oceanic environ- 

 ment, which contrasted markedly with Ronquil- 

 lo's (1953) work showing a great diversity of 

 organisms eaten in an environment influenced 

 by land. The fact that 5. buccaneeri was found 

 only in the stomachs of tunas from two schools 

 that were close to each other suggests that it 

 was not widespread in this area. 



SAMOA ISLANDS 



Table 2 shows the results of examining 205 

 skipjack tuna, 23 kawakawa, 24 yellowfin tuna, 



and 1 common dolphin which were caught on 

 cruise 117 of the Charles H. Gilbert. S. bucca- 

 neeri occurred very frequently in the stomachs 

 examined. Other fishes occurring frequently 

 belonged to the families Acanthuridae and Holo- 

 centridae. Stomatopod larvae, of the inverte- 

 brates, occurred most frequently in the contents. 

 Many of the stomachs examined were empty. 



The variety of organisms eaten around the 

 Samoa Islands was limited. However, a com- 

 parison of the studies shows a greater diversity 

 ingested around Samoa than in the equatorial 

 eastern Pacific, probably because of the proxim- 

 ity to the islands. The distribution of S. bucca^ 

 neeri was found to be widespread in this area. 

 Their frequency of occurrence in the stomachs 

 suggested that they were an important forage 

 for the tunas and dolphins here. 



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