FISHERY BULLETIN: VOL. 82, NO. 1 



TABLE 7.— Mean numerical and biomass densities (per 1,000 m 3 ) of fishes observed inn daily samples per depth stratum at the SOK-D area in 

 the San Onofre kelp bed during fall 1 97 9. Values are the grand means (± 1 standard error) of the daily means (adjusted for transect volume) over 

 transects taken each sampling day. 



TABLE 8. — Mean numerical densities (per 1,000 m 3 ) of young-of- 

 the-year (yoy), all juveniles (including yoy), subadult, and adult kelp 

 bass inn daily samples per depth stratum at SOK-U and SOK-D 

 during fall 1979. Grand means calculated as in Tables 6 and 7. 



kelp beds off northern San Diego County (DeMartini 

 et al. 6 ). 



Seven of the 13 common species were most abun- 

 dant near the bottom (Tables 5, 6, 7). Rainbow 

 seaperch and rock wrasse rarely, if ever, strayed 

 above the bottom. Black perch and rubberlip 

 seaperch were recorded occasionally at 12 m, but 



6 E. DeMartini, F. Koehrn, D. Roberts, R. Fountain, and K. Plum- 

 mer. Variations in the abundances of fishes within and between 

 stands of giant kelp {Macrocystis pyrifera) during successive years. 

 Manuscr. in prep. Marine Science Institute, University of Califor- 

 nia, Santa Barbara, CA 93106. 



were much more abundant on the bottom. Pile perch 

 were seen, at one site or the other, in all strata, but 

 were most abundant on the bottom and at 12 m. 

 Barred sand bass also concentrated on the bottom 

 and, to a lesser degree, at 1 2 m. California sheephead 

 were observed as shallow as 3 m at SOK-D, but no 

 shallower than 12 m at SOK-U. 



Species composition and relative abundance in 

 each stratum reflected the distributional patterns of 

 the species (Tables 9, 10). The three cosmopolitan 

 species were among the three to five most abundant 

 species in every stratum, particularly above the bot- 

 tom. At 3 and 7.6 m, they made up 89-99% of total 

 numerical density. The remaining fish in these strata 

 were mainly upper water-column species, with a few 

 of the more errant bottom species (such as California 

 sheephead and pile perch) entering at 7.6 m. The 

 three cosmopolites again dominated the assemblage 

 at 12 m, forming 86-94% of fish numbers. A few 

 individuals of canopy species were present at 12 m, 

 however, and a greater number of bottom species 

 were observed. The bottom stratum contained the 

 greatest number of recorded species, and individuals 

 were distributed more evenly among these species. 

 The cosmopolites were still among the most abun- 

 dant species on the bottom, but several of the 

 bottom-zone species (such as California sheephead, 

 black perch, and barred sand bass) were also abun- 



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