PERRIN ET AL.: STOMACH CONTENTS OF PORPOISE AND YELLOWFIN TUNA 



Table 5. — Stomach contents of yellowfin tuna and spotted porpoise taken in a single net haul: Haul 4. 



Ommastrephidae 



Ommastrephid A (probably 



Dosuiicus Kik'i^i'' ) 

 Ommastrephid B (probably 



Syniplecloteiithis sp.) 



Enoploteuthidae: 

 Ahnilmps is affinis 



Unid. octopod 



Unid. cephalopod fragments 



Unid. cephalopod beaks 



Crustaceans: 

 Portunidoe: 



Eiiphyliix dovii 



615 42.7 38 27.3 11 55.0 



609 42.3 27 19.4 10 50.0 



6 0.4 11 7.9 4 20.0 



tr. 



18 



1.3 - 



700 48.6 37 26.6 14 70.0 



135 20.7 14 — 1 33.3 



' Complete contents were preserved and volumed for only three stomachs. All fish remains were preserved; therefore 

 the sample size for fish number and occurrence is 23. For cephalopod toxa, the sample size is three. 



to those in Haul 2. Overlap was greatest in the 

 cephalopod component. The crab Euphylax 

 dovii was dominant in the tuna and absent in 

 the porpoise. The enoploteuthid squid Abraliop- 

 sis affinis was again present in the porpoise but 

 absent from the tuna. Nearly all of the fish 

 volume in the tuna was due to the presence of 

 four frigate mackerel, Auxis sp., in one stomach. 



Haul 4 



Tuna and spotted porpoise were again sampled 

 in Haul 4 (Table 5), and the same pattern 

 emerged as in the previous hauls. Portunid 



crabs were important in the tuna but absent 

 in the porpoise, and enoploteuthid squid were 

 present in the porpoise but absent in the tuna. 

 Except for Abraliopsis, the squid and fish com- 

 ponents were very similar for the two species 

 in this haul. 



Haul 5 



Both the tuna and the spotted porpoise in this 

 haul were engorged with freshly ingested Auxis 

 and squid (Table 6), and the makeup of the 

 contents in both volume and number was re- 

 markably similar. They had obviously fed on 

 the same food at the same time. Abraliopsis 



1085 



