Table 1 . — Results from sampling at three stations on the eastern side of Oahu and at a 

 supplementary site off west Oahu. Numbers in parentheses indicate the actual dive 

 depths (in meters). 



tosus at anchor just prior to the dive. At station 

 2, a somewhat shallower (52 m) dive revealed a 

 substrate consisting entu'ely of soft HaUtneda 

 sand without invertebrate burrows or visible 

 fine sediment. After the bottom observations, 

 additional fishing at >61 m depths yielded a 

 single P.filamentosus. 



Since the density of juvenile lutjanids was 

 probably not great at any location, it is not sur- 

 prising that they were never sighted by divers. 

 Avoidance behavior by the juveniles may have 

 contributed to the lack of sightings. Our im- 

 pressions of the habitat based on dive observa- 

 tions were consistent with those from other 

 surveys of the study area (Smith et al. 1973; 

 Coulbourn et al. 1988). 



The portion of the life cycle during which 

 juveniles occupy the observed habitat remains 

 unknown. Fork lengths (FL's) of the collected 

 P. filamentosHS (ji = 32) ranged from 10.1 to 

 20.7 cm; most individuals were clumped at the 

 low end of the range. Planktonic individuals as 

 large as 5 cm have been recorded for a some- 

 what smaller species, P. sieboldii, by Leis 

 (1987). Until the present study, the smallest 

 recorded P. filamentosiis was 18 cm FL, caught 

 by handline during sampling for adults (Ralston 

 1981). Using Ralston and Miyamoto's (1983) 

 estimated growth curve derived from adult 

 specimens, a fish of 18 cm FL would be approxi- 

 mately 1 yr old. 



Larger identifiable prey items recovered from 

 the stomachs of 22 juvenile specimens oi P.fila- 



mentosus included early juvenile fish (probably 

 recently settled) and cephalopods (including 

 an octopod) (Table 2). The hindgut contained 

 small planktonic crustaceans, appendicularians, 

 and other gelatinous plankton. Most prey indi- 

 viduals were sinall, but the general taxonomic 

 composition of the diet of the juveniles did not 

 appear greatly different from that of adults. 

 Crustaceans and salps commonly occur in the 

 diet of adult P. filamentosus (Kami 1973; Par- 

 rish 1987). 



Table 2.— Approximate percentage of number and frequency 

 of identifiable prey items found in Prlstipomoldes fllamentosus 

 juveniles (n = 22). 



Prey type 



Percent 

 occurrence 



Percent 

 frequency 



Relatively flat, soft bottoms such as occur at 

 these stations have been largely ignored as 

 potentially important habitat for these deep- 

 water lutjanids, but they may provide essential 

 habitat for the juveniles. Artificial structures 

 placed in depths of 61-117 m in Hawaii success- 

 fully aggi'egated deepwater lutjanid adults, but 



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