FISHERY BULLETIN: VOL. 72, NO. 4 



there are relatively few in the Kona study area. 

 During the day this species stays close to cover, 

 where it usually occurs in small groups under 

 ledges. At night solitary individuals are active 

 close among rocks and coral on the reef. 



Of the 11 specimens (157: 137-173 mm) col- 

 lected, 6 speared close to reef crevices late in the 

 afternoon either were empty or contained only a 

 few well-digested fragments, whereas all 5 col- 

 lected in the same places within 1 h after sunrise 

 had stomachs full of prey, some of it fresh, as listed 

 in Table 27. 



CONCLUSION .—Parupeneus porphyreus is a 

 nocturnal predator that feeds mostly on benthic 

 crustaceans. 



Parupeneus chrtjserydros (Lacepede) — moano 

 kea 



The scientific name of this goatfish remains un- 

 certain. I follow Gosline and Brock (1960) in rec- 

 ognizing the nominal P. chryserydros, even 

 though some authors (e.g. Lachner, 1960) refer 

 this form to P. cyclostomus (Lacepede). Growing to 

 about 600 mm long (Gosline and Brock, 1960), P. 

 chryserydros is the largest of the goatfishes occur- 

 ring regularly on Kona reefs. 



During the day, solitary individuals or groups of 

 two to five move over the reef, where their excep- 

 tionally long barbels work through the covering 

 on rocky substrata. More often than not, groups of 

 P. chryserydros are accompanied by a single jack, 

 Caranx melampygus, which follows close behind 

 them. For 1 mo I recorded all sightings of P. 

 chryserydros that swam in groups of two or more, 

 and of 24 such groups, 16 were accompanied by a 

 jack. Usually solitary individuals of this goatfish 

 are not thus accompanied, but this too was seen 

 four times during the month. Clearly, it is the jack 

 that maintains the association, probably as a tac- 



tic to capture prey driven from cover as the forag- 

 ing goatfish disturb the substratum. Apparently 

 the jack finds this advantage only with P. 

 chryserydros, as it was not seen similarly follow- 

 ing other species. Titcomb and Pukui ( 1952) listed 

 many ancient Hawaiian fish names which they 

 were unable to associate with species recognized 

 today. One of these, moano ukali ulua, translates 

 as "moano with ulua following," and probably re- 

 fers to P. chryserydros. Whereas the adults of P. 

 chryserydros are followed by the jack, the 

 juveniles of this goatfish frequently swim close 

 beneath various labrids, especially Thalassoma 

 duperrey, and here it is the goatfish that main- 

 tains the associations, though to what advantage I 

 do not know. 



Of the 20 specimens (261: 123-363 mm) col- 

 lected, all 3 that were speared as they rested on the 

 reef at night (between 4 h after sunset and first 

 morning light) had empty guts, whereas 15 of 17 

 taken as they swam close to the reef at various 

 times of the day (between midmorning and late 

 afternoon) had prey in their stomachs, and only 

 the other 2 were empty. 



Fish were the major item, occurring in 13 of the 

 15 individuals that contained food (mean percent 

 of diet volume: 83.1; ranking index: 72.02). Other 

 food items were: xanthid crabs in two individuals 

 (mean percent of diet volume: 8.3; ranking index: 

 1.11), caridean shrimps in one (mean percent of 

 diet volume: 1.3; ranking index: 0.09), and 

 unidentified fragments in two (mean percent of 

 diet volume: 7.3; ranking index: 0.97). 



The fishes in the diet ranged between 25 and 102 

 mm long, and included the following species: 

 Abudefduf imparipennis (1), Cirrhitops fasciatus 

 (2), Istiblennius gibbifrons (1), Plagiotremus gos- 

 linei (1), Cirripectus sp. (4), and a labrid (1). All of 

 these are diurnal fishes that swim close to the reef 

 in daylight, but take cover when a predator ap- 

 proaches. Judging by how P. chryserydros feeds. 



Table 27. — Food of Paruperfus porphyreus. 



962 



