first or second as prey of three of the five West 

 Indian boxfishes studied by Randall (1967). 

 Furthermore, polychaetes and sponges also were 

 found to be important prey in the Atlantic species 

 just as they are in O. meleagris from Kona. In the 

 Marshall Islands, the major foods of O. cubicus 

 are mollusks, polychaetes, and algae (Hiatt and 

 Strasburg, 1960). 



At least some boxfishes, including O. meleagris 

 in Hawaii (Gosline and Brock, 1960; Thomson, 

 1964), release a substance that is toxic to other 

 fishes. This may give them some immunity from 

 predation, as suggested for some tropical Atlantic 

 species by Randall (1967). 



Family Tetraodontidae: balloonfishes 



Arothron hispidus (Linnaeus) — opn hue, keke 



This solitary balloonfish is widespread on Kona 

 reefs, but is nowhere numerous. In daylight it 

 frequently hovers inactively several meters above 

 the reef, although just as often it swims slowly 

 among the rocks and coral. After dark it continues 

 to swim actively, close to the reef. 



Nine individuals (253: 187-332 mm) were 

 speared during day and night. The guts of two 

 were empty: one of these was hovering high in the 

 water column during early afternoon when col- 

 lected; the other was swimming close among rocks 

 during the hour immediately before first morning 

 light. All of the other seven, taken as they swam 

 close to the reef — five during midday, two during 

 midnight — contained identifiable material, as 

 listed in Table 70. The tunicates taken by this 

 balloonfish include several benthic species, both 

 compound and simple forms; the echinoids are the 

 crushed tests and spines of echinometrids and 

 cidarids; the asteroids are mostly tips of the ap- 

 pendages from Linckia. 



FISHERY BULLETIN: VOL. 72, NO. 4 



Generally the items are hard-bodied forms that 

 remain recognizable for a relatively long time 

 after ingestion; nevertheless, material from the 

 two individuals collected at night appeared 

 fresher overall than that from the individuals col- 

 lected during midday. 



In the Marshall Islands, the single A. hispidus 

 examined by Hiatt and Strasburg (1960) had fed 

 on much the same material as listed above, except 

 that it also had ingested some living scleractinian 

 corals. 



CONCLUSION. — Arothron hispidus preys on 

 a variety of benthic invertebrates, especially 

 those having a hard or leathery external covering. 

 Limited evidence indicates it is active during 

 both day and night. 



Arothron meleagris (Bloch and Schneider) — 

 'opu hue, keke 



Like its congener A. hispidus, above, the soli- 

 tary species A. meleagris (Figure 41) is wide- 

 spread on Kona reefs, but is nowhere numerous. It 

 does not hover inactively above the reef during 

 the day as A. hispidus often does, and on the few 

 occasions when it was seen at night — always 

 under ledges or in crevices — A. meleagris seemed 

 inactive. During daylight it swims slowly among 

 the rocks or corals. 



Eleven individuals (221: 146-393 mm) were 

 collected during the day. Of three whose guts were 

 empty, two were speared as they swam close to the 

 reef within an hour after sunrise, and one was 

 taken from a small cave during midafternoon. The 

 remaining eight, taken as they swam close to the 

 reef during midday, all contained identifiable 

 material. Seven of these had taken scleratinian 

 corals (mean percent of diet volume: 43.1; ranking 

 index: 37.71), mostly small chunks of encrusting 



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