FISHERY BULLETIN: VOL. 72, NO. 4 



with peaks during twilight (Hobson, 1965, 1968a). 

 On the other hand, nocturnal habits were noted in 

 Alphestes multiguttatus and Rypticus bicolor (the 

 latter is often placed in a separate family, the 

 Grammistidae), both of which prey chiefly on 

 benthic crustaceans (Hobson, 1965, 1968a). In the 

 same reports, a fourth sea bass, Epinephelus lab- 

 riformis, was reported to feed by both day and 

 night, chiefly on fishes in daylight and on benthic 

 crustaceans after dark. These data suggest that 

 fishes may be the major prey of sea basses in day- 

 light with crustaceans predominating after dark, 

 a generalization consistent with the limited ob- 

 servations on Cephalopholis argus in Kona. 



Starck and Davis (1966) noted that serranids of 

 the genera Epinephelus, Mycteroperca, and 

 Petrometopon behave similarly day and night in 

 the Florida Keys, with probable feeding peaks 

 around sunrise and sunset. Longley and Hilde- 

 brand (1941) reported that Epinephelus morio 

 feeds during both day and night in the Dry Tor- 

 tugas, Fla., and Randall (1967) noted that larger 

 serranids in the West Indies feed both day and 

 night, with greatest activity at dawn and dusk. 

 Collette and Talbot (1972), on the other hand, 

 reported E. guttatus in the Virgin Islands to be 

 active by day and apparently asleep at night. They 

 also found E. fulvus and E. cruentatus active in 

 daylight and suspected that these sea basses rest 

 at night. Randall (1967) considered the smaller 

 serranids, in general, to be primarily diurnal. 

 In Florida, Starck and Davis (1966) regarded 

 certain small serranids of such genera as Diplec- 

 trum, Hypoplectrus, and Serranus to be active by 

 day and inactive by night. None of these authors 

 attempted to relate time of activity with kinds 

 of prey. 



Family Kuhliidae: aholeholes 



Kuhlia sandvicensis (Steindachner) — aholehole 



This predator occurs in only a few locations 

 within the Kona study area, and there just 

 sparsely, compared to its large numbers elsewhere 

 in Hawaiian nearshore waters. Juveniles and 

 young adults live in tide pools or in schools close to 

 shore (Gosline and Brock, 1960), but the larger 

 adults congregate during the day under low ledges 

 and boulders, usually in water less than 5 m deep 

 farther from shore. They emerge from shelter at 

 nightfall, and the few observed after dark during 

 this study were solitary in the water column over 



the reef. Gosline and Brock (1960) noted that the 

 adults, at least, are nocturnal, a conclusion consis- 

 tent with the large eyes of the species. 



Of the 13 specimens (164: 132-202 mm) col- 

 lected, 8 speared during midmorning from under 

 rocky cover contained in their stomachs exten- 

 sively digested crustacean fragments (including 

 crab megalops), 1 taken under a rock at noon con- 

 tained only well-digested material scattered 

 through its intestine, and 4 speared under rocks 

 late in the afternoon were empty. 



CONCLUSION. — Kuhlia sandvicensis is a 

 nocturnal predator that feeds on free-swimming 

 crustaceans. 



Family Priacanthidae: bigeyes 



Priacanthus cruentatus (Lacepede) — bigeye, 

 aweoweo 



This priacanthid (Figure 18) is numerous in 

 Kona, where it takes shelter under rocks or coral 

 during the day, often in groups, and is active in the 

 open at night. After emerging from shelter at 

 nightfall, many individuals assemble in schools 

 high in the water column and then migrate 

 offshore. These do not return inshore until about 

 40 min before sunrise, but a lesser number of other 

 individuals, mostly solitary or in small groups, 

 remain over the inshore reefs throughout the 

 night. All of these fish return to their daytime 

 shelter by 30 min before sunrise, at least many of 

 them to specific home caves (Hobson, 1972). 



Forty specimens (173: 115-255 mm) were col- 

 lected during day and night. All 17 that were 

 speared during morning twilight (shortly after 

 they had reappeared near their diurnal shelter, 

 but before they had taken cover) had relatively 

 fresh prey in their stomachs. Four others were 

 collected from under cover during late morning, 

 and although all had full stomachs, with many 

 items identifiable, digestion was advanced, and 

 most of the material was damaged beyond recog- 

 nition. The other 19 were collected from caves late 

 in the afternoon, and although only 4 of these had 

 empty stomachs, the material in the other 15 was 

 reduced to unidentified fragments. Items in the 21 

 specimens containing identifiable material are 

 listed in Table 19. 



Hiatt and Strasburg (1960) acknowledged that 

 species of Priacanthus generally are thought to be 

 nocturnal, but contested this opinion as far as P. 



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