FISHERY BULLETIN: VOL. 77, NO 4 



from others to escape exposure to infected fish, 

 even pelagic larvae. 



Yet, neither tagging nor parasite data indicated 

 whether fish move offshore from the Ellwood area 

 to Naples Reef. However, size-frequency data of 

 fish taken on Naples Reef and at Haskels (adjacent 

 to the Ellwood Pier) (Figure 2), are evidence that 

 there was probably little movement from Ellwood 

 to Naples. Naples Reef harbors primarily juvenile 

 and preadult olive rockfish (Love and Ebeling 

 1978) and adults are rarely observed (Ebeling^). 

 Apparently, fishing pressure removes fish before 

 they can mature. However, adults were abundant 

 at the lightly fished Ellwood Pier, and limited 

 sampling along a 16 km stretch of kelp inshore of 

 Naples Reef indicated that mature fish were com- 

 mon throughout the bed. Apparently, few of these 

 fish move across the sandy stretch between Naples 

 Reef and the inshore bed. 



Though inshore movements seem to be inhibit- 

 ed by stretches of sandy bottom, movement from 

 one oil platform to another obviously is not: tagged 

 fish must traverse at least 0.8 km over sandy bot- 

 tom with a depth of about 50 m to reach the adja- 

 cent site. Miller and Geibel ( 1973) observed a simi- 

 lar greater mobility in deep waters for blue 

 rockfish, S. mystinus. 



Olive rockfish off Santa Barbara feed primarily 

 on midwater organisms (nekton and plankton) 

 rather than substrate-oriented prey (Love and 

 Ebeling 1978). It is not known whether these prey 

 are less abundant at the platforms compared with 

 inshore waters. However, if they are less abun- 

 dant, olive rockfish might be more likely to leave 

 the platform to follow prey. I have noted olive 

 rockfish feeding on anchovies as much as 300 m 

 away from the platforms. Perhaps in these in- 

 stances some fish may not return to the original 

 platform. 



This study emphasized movements of fish that 

 inhabit isolated reefs. Little work was done on fish 

 from the extensive area of continuous kelp forest 

 which grows mostly on sandy bottom and parallels 

 most of the Santa Barbara coast, because sam- 

 pling is more time consuming in such areas of low 

 rockfish densities. Moreover, much of the tagging 

 was done aboard partyboats which rarely fish 

 these extensive beds. It is quite possible that olive 

 rockfish in kelp beds move about considerably 



more than those on isolated reefs. I suspect that 

 the limited movements observed may be due to the 

 lack of cover on the relatively barren bottom sur- 

 rounding the reeflike study sites. Olive rockfish 

 have been rarely taken over sand, either in otter 

 trawls (Ebeling et al.**), or seen in underwater 

 transects in kelp beds over a sand bottom (Quast 

 1968), and seem to be strongly attracted to high- 

 relief substrate, such as that of platforms and 

 rocky reefs. Kelp beds may provide "bridges" from 

 one reef to smother. 



Previous studies (Table 4) indicate that many 

 other shallow water rockfish exhibit limited 

 movements. The two most extensively investi- 

 gated benthic species, S. carnatus and S. 

 chrysomelas, defend small feeding territories and 

 shelter holes (Larson 1977; Hallacher 1977). 

 Also, agonistic displays by S. serriceps (Feder et 

 al. 1974; Haaker 1978) and long-term residence 

 in particular crevices by S. nebulosus (McEl- 

 derry') indicate that these benthic species may 

 also be territorial. Thus, it seems likely that most 

 or all benthic reef rockfish may move relatively 

 little. 



Similarly, some midwater rockfishes that live 

 over these shallow reefs, seem to stay within a 

 fairly small area. In particular, tagging of S. mys- 

 tinus (Miller and Geibel 1973) indicated re- 

 stricted movements, and tagging of S. flavidus 

 (Carlson and Haight 1972) showed that this 

 species has a strong homing tendency. However, 

 movements of tagged S. melanops (Coombs 1979), 

 along with pelagic capture (Dunn and Hitz 1969) 

 indicate that it probably moves about exten- 

 sively. 



Relatively parochial midwater rockfish, such as 

 S. mystinus, S. serranoides, and S. flavidus, do 

 not appear to be territorial, in the sense that a 

 territory is a "defended" (Noble 1939) or "exclu- 

 sive" (Schoener 1968) area. Indeed, these species 

 often form single or multispecies aggregations of 

 thousands of individuals, which show little or no 

 agonistic behavior. The sizes of rockfish home 

 ranges have not been estimated, though Miller 

 and Houk* believed that S. mystinus aggrega- 



'Ebeling, Alfred W. Department of Biological Sciences, Uni- 

 versity of California, Santa Barbara, CA 93106, pers. commun. 

 February 1978. 



'Ebeling, A. W., W Werner, F. A Dewitt, Jr . and G M. 

 Cailliet. 1971. Santa Barbara oil spill: short-term analysis of 

 macroplankton and fish. EPA, Water Qual. Off. Doc. no. 

 15080EA02/71, 68 p. 



'H. McElderry Department of Biology, University of Victoria, 

 Victoria, B.C. pers. commun. January 1978. 



«D. Miller and J Houk, California Department of Fish and 

 Game, 2201 Garden Road, Monterey, CA 93940, pers. commun. 

 January 1978. 



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