FISHERY BULLETIN: VOL. 83, NO. 2 



Table 4. — Prey taxa comprising ^1*^ of the diet (by IRI) of immature, adult male, and 

 adult female queenfish during the two periods of onshore distribution combined. Sample 

 fish collected during both day and night and at shallow (5-10 m) and middepths (11-16 m) 

 are pooled (see text). Diet characterized by number (N), reconstructed wet weight (Wt), and 

 frequency of occurrence (FO) of prey; overall contribution to diet evaluated by IRI (Pinkas et 

 al. 1971). Prey ranked by IRI within queenfish categories. A^ = number of fish examined 

 that had food in their stomachs. Mean (and range I of body lengths (SL, mm) of fish examined 

 were immatures — 70 (34-100), adult males— 127 (76-210), and adult females — 146 (102- 

 214). 



night for both immature and adult queenfish 

 (Table 5), indicating that all sizes of fish fed 

 primarily at night. 



DISCUSSION AND CONCLUSIONS 



Functions of Nocturnal 

 Offshore Dispersal in Queenfish 



Diel migrations of queenfish have been previ- 

 ously reported. Queenfish have been directly ob- 

 served emigrating offshore at dusk from inactive 

 daytime schools nearshore at Santa Catalina Is- 

 land, one of the Channel Islands offshore of the 

 southern California mainland (Hobson and Chess 

 1976; Hobson et al. 1981). Similar behavior has 



been noted by Hobson^ in mainland waters off La 

 Jolla, near San Diego. Allen and DeMartini (1983) 

 have characterized the general pattern of noctur- 

 nal offshore dispersal of queenfish near San Diego. 

 Direct observation (Hobson and Chess 1976; Hob- 

 son et al. 1981) and examination of stomachs offish 

 collected during the day and at night (Hobson and 

 Chess 1976; Hobson et al. 1981; Allen and DeMar- 

 tini 1983; this study) confirm the primarily noc- 

 turnal feeding habits of queenfish. A spawning 

 function has also been implicated for the offshore 

 movements of adult queenfish at dusk (DeMartini 



'Edmund S. Hobson, Southwest Fisheries Center Tiburon 

 Laboratory, National Marine Fisheries Service, NOAA, 3150 

 Paradise Drive, Tiburon, CA 94920, pers. commun. May 1978. 



180 



