FISHERY BULLETIN: VOL. 72, NO. 4 



Figure 17. — Scorpaena coniorta, a scorpionfish, nestled among coral branches during the day. 



captured during the day. In comparison, 14 of 22 

 individuals collected at night, between 3 h after 

 sunset and first morning light, had food in their 

 stomachs. Brachyuran crabs, almost all of them 

 xanthids, occurred in 7 of the 15 individuals that 

 contained identifiable items (mean percent of diet 

 volume: 39; ranking index: 18.2). Caridean 

 shrimps occurred in six (mean percent of diet vol- 

 ume: 28.3; ranking index: 11.33), and fishes in one 

 (mean percent of diet volume: 6.7; ranking index: 

 0.45). Unidentified crustacean fragments oc- 

 curred in six (mean percent of diet volume: 26; 

 ranking index: 10.4). Many of the xanthids and 

 carideans found in specimens less than 50 mm 

 long are forms that cooccur with these fish among 

 the coral branches. 



CONCLUSION. — Scorpaena coniorta is a noc- 

 turnal predator that takes benthic crustaceans, 

 mostly xanthid crabs and caridean shrimps. Some 

 prey are also captured during the day. 



Scorpaenopsis cacopsis Jenkins — nohu 'oniakaha 



This species, the largest Hawaiian scorpaenid, 

 grows to over 50 cm long (Gosline and Brock, 

 1960) I observed no overt difference in its be- 

 havior between day and night as it was seen rest- 



ing immobile on the reef at all hours, often fully 

 exposed. Despite its large size and frequent dis- 

 dain for cover, this fish remains virtually unseen, 

 owing to body hues and texture that render it 

 much like the reef on which it rests. It was not seen 

 feeding, but its morphology and behavior suggest 

 that it lunges forward to attack prey that have 

 strayed within range, and sucks them in with a 

 sudden expansion of its cavernous mouth. 



Of the five specimens (256: 73-375 mm) ex- 

 amined, three had prey in their stomachs: one, 

 taken within 1 h after sunrise, contained a fresh 

 fish, Pomacentrus jenkinsi (104 mm); a second 

 taken at night, 4 h after sunset, contained a rel- 

 atively fresh octopus; and the third, taken late in 

 the afternoon, contained fish fragments. The 

 other two, both empty, were collected during 

 morning twilight. 



CONCLUSION. — Scorpaenopsis cacopsis 

 attacks fishes and motile invertebrates during the 

 day. Its nocturnal activity remains uncertain. 



General Remarks on Scorpionfishes 



Scorpionfishes on tropical reefs are widely de- 

 scribed as predators that rest on the bottom, and 



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