DRAGOVICH and POTTHOFF: FOOD OF SKIPJACK AND YELLOWFIN TUNAS 



NUMBER 



SKIPJACK TUNA 



UN -6801 



VOLUME 



FREQUENCY OF OCCURRENCE 



Fishes 



Crustaceans I 



Cephalopods | 



Other mollusks | 



Miscellaneous | 



Fishes 



Crustaceans 

 Cephalopods | 

 Other mollusks I 

 Miscellaneous I 



UN -6802 



I 



I 



YELLOWFIN TUNA 



NUMBER 



UN- 6801 



VOLUME 



FREQUENCY OF OCCURRENCE 



Fishes 



Crustaceans I 



Cephalopods I 



Other mollusks | 



Miscellaneous | 



Fishes 

 Crustaceans 

 Cephalopods 

 Other mollusks 

 Miscellaneous 



PERCENT 



UN-6802 



50 



PERCENT 



100 



50 



PERCENT 



Figure 3. — Percentage of total food (by five categories) in stomachs of skipjack 

 and yellowfin tunas captured during cruises UN6801 and UN6802 off the west 

 coast of Africa. Food items are represented in terms of numbers, volumes, and 

 frequency of occurrence. 



For UN6801, fish families Acanthuridae, Ca- 

 rangidae, Dactylopteridae, Gempylidae, Gonos- 

 tomatidae, Lutjanidae, Mullidae, Priacanthidae, 

 Scombridae, and Serranidae ranked high in 

 terms of volume and frequency of occurrence 



for both species of tunas. Owing to the large 

 numbers of V. nimbaria in the diet of both spe- 

 cies of tunas, the family Gonostomatidae was 

 the most important forage item for both species 

 in terms of volume. In the diet of skipjack tuna, 



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