FISHERY BULLETIN: VOL. 83, NO. 2 



Table 6. — Prey taxa comprising ^1% of the diet (by IRD of immature, adult male, and 

 adult female queenfish collected during the night from the mid-depth (11-16 m) block. Data 

 for the two periods of onshore distribution are pooled; for further details of diet characteriza- 

 tion see Table 4. Mean (and range) of body lengths (SL, mm) were immatures — 71 (42-86), 

 adult males — 126 (83-183), and adult females— 147 (103-207). 



are well recognized (Barnard and Given 1961; 

 Hobson and Chess 1976). 



The significant amount of shallow-living prey 

 such as D. tenuis and Labidocera trispinosa pres- 

 ent in the stomachs of queenfish captured offshore 

 at night (Table 6) nonetheless clearly illustrates 

 that these fish had recently emigrated from depths 

 nearer to shore. Numerous data characterize D. 

 tenuis as largely restricted to within the 30 m 

 isobath (Barnard and Given 1961; Parr and 

 Diener'). Diastylopsis tenuis, in fact, declines >1 

 order of magnitude in abundance in benthic core 



^Parr, T. D., and D. D. Diener San Onofre sand bottom 

 benthic studies, San Onofre Nuclear Generating Station 

 (SONGS) Units 2 and 3, pre-oi>eration monitoring results. Vol- 

 ume 2. A study submitted to the Marine Review Committee of 

 the California Coastal Commission, May 8, 1981. Unpubl. rep., 

 109 p. Marine Ecological Consultants of Southern California, 

 531 Encinitas Boulevard, Encinitas, CA 92024. 



samples between 8 and 15 m depths near San 

 Onofre (Parr and Diener footnote 7). Labidocera 

 trispinosa, a holoplanktonic copepod, also has 

 been described as much more abundant inshore of 

 12-15 m bottom depths, both off La Jolla (Barnett 

 1974) and off San Onofre-Oceanside (Barnett et 

 al.^). It seems less likely that nearshore forms 

 such as D. tenuis andL. trispinosa are more avail- 

 able as prey offshore at night, since they are 

 markedly less abundant offshore. 



The presence of offshore prey in the stomachs of 

 adult queenfish collected offshore obviously re- 

 flects nocturnal foraging while in that region. 



^Barnett, A. M., A. E. Jahn, P D. Sertic, and S. D. Watts. The 

 ecology of plankton off San Onofre Nuclear Generating Station, 

 Volume II. A study submitted to the Marine Review Committee 

 of the California Coastal Commission, April 30, 1981. Unpubl. 

 rep., 105 p. Marine Ecological Consultants of Southern 

 California, 531 Encinitas Boulevard, Encinitas, CA 92024. 



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