FISHERY BULLETIN: VOL. 78, NO. 2 



perch, Brachyistius frenatus, and senorita, 

 Oxyjulis californica) usually aggregated within 

 and just below the kelp canopy; "bottom species" 

 (e.g., gopher rockfish, Setes^es carnatus) rested on 

 the rocky reef surface far below; while "commuter 

 species" (e.g., kelp bass, Paralahrax clathratus) 

 swam about at all depths. "Inner-marginal 

 species" (e.g., black perch, Embiotocajacksoni) oc- 

 curred abundantly over mixed rock and sand in- 

 shore as well as deeper reefs offshore. Members of 

 different groups tended to mingle in areas of con- 

 tinuous reef and kelp where habitat types were 

 close together. The more complex and extensive 

 island reefs harbored the greatest numbers of 

 "reef specialists" in the kelp-rock group. 



The present study is an analysis of annual var- 

 iability in species composition, diversity, and 

 abundance of kelp-bed fishes in the faunistically 

 transitional (Neushul et al. 1967; Hubbs 1974; 

 Horn and Allen 1978) Santa Barbara Channel. 

 There have been few long-term studies of stability 

 and variability in reef-fish communities (Thomson 

 and Lehner 1976; Sale 1978). Yet, understanding 

 the scope and causes of variation in natural com- 



munities has both practical and theoretical impor- 

 tance (Larkin 1978; Wolda 1978). Our primary 

 purposes, therefore, were to 1) document yearly 

 changes in kelp-bed fish assemblages, which had 

 previously impressed us as appearing relatively 

 uniform in time, and 2) relate observed changes to 

 environmental variables that we could readily ob- 

 serve. Secondarily, we assessed the use of under- 

 water movies to census fishes in a complex envi- 

 ronment. To these ends, we made annual censuses 

 of fishes in and about the canopy of giant kelp and 

 over the bottom in areas of continuous rock reef at 

 sites off the Santa Barbara mainland and Santa 

 Cruz Island. 



METHODS 



Study Sites 



Sampling was conducted in areas of rocky reef 

 and kelp on either side of the Santa Barbara 

 Channel (Figure 1). Our mainland sampling site 

 was Naples Reef, an isolated system of rocky out- 

 crops and ledges located about 1.6 km offshore, 24 



PT. CONCEPTION 



MONTEREY 266 KM V 

 SAN DIEGO 342 KM 



N 



MAINLAND SITE 



w-^ 



f,HTA BARB^^^ 



'^*N HEL 



SAN MIGUEL IS, 



ISLAND SITE 



*NACAPa 



IS. 



25 KM 



FIGURE 1.— Study sites for yearly sampling of fish assemblages in areas of reef and kelp off Santa Barbara, southern California. 

 Circled letters identify the mainland site, Naples Reef (NA), and the island site, Fry's Harbor and vicinity (FR). 



362 



