FISHERY BULLETIN: VOL. 72, NO. 4 



Table 65. — Food oi Rhinecanthus rectangulus. 



CONCLUSION. — Rhinecanthus rectangulus is 

 a diurnal omnivore, feeding mostly on gammari- 

 dean amphipods and other small organisms. 



Sufflamen bursa (Bloch and Schneider 

 humuhumu umaiima lei 



This is the most numerous and widespread 

 triggerfish on Kona reefs. A solitary species, ac- 

 tive by day close to rocks and coral, it picks at 

 organisms on the sea floor. It is less inclined to 

 seek cover in reef crevices than are Melichthys 

 niger and Rhinecanthus rectangulus, above, but 

 nevertheless is a wary animal that shys away 

 from humans. At night it is inactive, resting on its 

 side under cover on the reef until morning. 



Thirteen individuals (140: 109-164 mm) were 

 speared at various times of day and night. The four 

 that were collected in darkness as they rested in 

 reef crevices during the last 2 h before daybreak 

 were empty, whereas the nine that were collected 

 at various times during the day as they swam over 

 the reef were full of food, as listed in Table 66. As 

 was true of the food of R. rectangulus, these food 

 items, including the echinoids, are mostly small 

 animals between 1 and 6 mm in their greatest 

 dimension, taken intact; the exceptions are frag- 

 ments of about this size from larger organisms. 

 Unlike the omnivorous R. rectangulus, however, 

 S. bursa seems to be strictly carnivorous (the few 

 algal fragments among its gut contents probably 

 were taken incidentally along with prey). No 



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