FISHERY BULLETIN: VOL. 74, NO. 3 



15. MYSIDS(3:<0.1:<0.1) 



Siriclla pacifica. 



16. CUMACEANS(3:<0.1:<0.1) 



CyclaspiK niihiki. 



17. CARIDEAN ADULTS AND JUVENILES (3: <0.1: <0.1) 



Hippolyte clarki. 



Although these fish preyed heavily on zoo- 

 plankters, clearly many of the organisms in the 

 above list were plucked from a substrate. The 

 major gammaridean, Microjas.sa litodes, was 

 never seen or taken by us in the water column, but 

 was a predominent form on the surface of giant 

 kelp (Hobson and Chess in prep.) Similarly, the 

 many forms known to occur in the water column 

 only at night, e.g., Siriella pacifica, Cyclaspi>; 

 nubila, Pa race tries sp., Batea transversa, and 

 Hippolyte clarki were probably plucked by these 

 day feeders from the algae or sand where they 

 occur in the daytime. 



Foods taken by individuals that had been feed- 

 ing at night are ranked below. 



1. GAMMARIDEAN AMPHIPODS (100: 3.3.8: 71.1) 



Batea tram^rcrsa (66: 8.1: 22.1); Ericthuiiiax hrazilieusis 

 (44: 0.9: 2.6); Micnijasya lito(h'!< {22: 1.6: 1.7); Ampithoe spp. 

 (22: 0.3: 0.9); Hjiah nigra (11: 0.4: 0.9); Aoroides columhiat 

 (11: 0.1: 0.3); unidentified, at least some probably juveniles 

 of the above (100: 22.4: 42.6). 



2. CAPRELLID AMPHIPODS (66: 4.4: 15.0) 



Caprella califoniica (55: 2.0: 9.5); C. pilidigifa (11: 2.0: 4.1); 

 unidentified (22: 0.4: 1.4). 



3. ISOPODS (44: 0.5: 6.6) 



Paracercies sp. 



4. CARIDEAN ADULTS AND JUVENILES (55: 0.7: 5.1) 



unidentified. 



5. MYSIDS(22:0.2:1.1) 



Siriella pacifica (12: 0.1: 1.0); erythropinid sp. (11: 0.1: 0.1). 



6. POLYCHAETES, NONSWIMMING (22: 0.2: 0.3) 



Spirnrbis sp. 



7. OSTRACODS (22: 0.2: 0.2) 



Parasterope sp. A (12: 0.1: 0.1); Cytlicre.^ia sp. (11: 0.1: 0.1). 



8. FORAMINIFERANS(11:0.1:0.2) 



unidentified. 



9. HARPACTICOID COPEPODS (11: 1.0: 0.1) 



Porcellidium sp. A. 



Two specimens also contained fragments of 

 algae {Macrocystis in one, Sargassiun in the other) 

 that probably had been taken incidentally along 

 with prey. Clearly this fish took at least some of its 

 nocturnal prey from a substrate- Spirorbis sp., for 

 example. Nevertheless, because the diet is com- 

 prised mostly of organisms that swim in the water 

 column at night, we believe this was probably 

 where most of them were taken. Most of these 

 prey organisms also occurred on rocks and algae 

 after dark, but if substrate-feeding had 



predominated, we would have expected a greater 

 proportion of strictly substrate-dwelling forms. 



Oxyjulh californica—sehont2i 



The senorita, which can attain a length of 250 

 mm (Miller and Lea 1972), is perhaps the most 

 widespread fish in nearshore habitats at Santa 

 Catalina Island. It is strictly a diurnal species that, 

 like other labrids, rests under cover on the sea floor 

 at night (Hobson 1971). Often during the day it 

 swims in large assemblages 1 to 2 m above the sea 

 floor (Figure 12). 



Most senoritas feed by plucking material from 

 the surface of algae-often from algae drifting as 

 fragments in the mid-waters-but plankton-feed- 

 ing is widespread, and predominates in smaller 

 juveniles. Limbaugh (1955) concluded that the 

 senorita is an omnivorous carnivore that feeds "on 

 almost any animal protein." Hobson (1971) found 

 that specimens between 110 and 195 mm long had 

 fed primarily on bryozoans that encrust algae, and 

 on caprellid amphipods. Quast (1968) reported the 

 principal foods to be small gastropods and crus- 

 taceans commonly associated with algae, but 

 noted that specimens 50 to 60 mm long had fed 

 heavily on copepods, ostracods, and bryozoan 

 larvae. 



Direct observations, complemented by our food 

 habit data (see below), agree that smaller in- 

 dividuals mostly pluck their prey from the water 

 column, whereas larger individuals mostly pluck 

 their prey from some substrate. In this respect, 

 then, the senorita is similar to the kelp perch, 

 described above. So, as with the kelp perch, this 

 paper considers only those individuals less than 

 100 mm long, leaving the larger individuals for a 

 later paper. We have better reason for drawing 

 the dichotomy at this point with the sefiorita than 

 with the kelp perch: the smallest senorita we found 

 containing prey obviously plucked from a sub- 

 strate was 101 mm long, and although planktivo- 

 rous habits predominated in certain individuals up 

 to 175 mm (which were among the largest taken), 

 most over 100 mm seemed to feed primarily on a 

 substrate. So unlike the diverse feeding habits of 

 smaller kelp perch, the smaller senoritas seemed 

 strictly planktivorous. Bray and Ebeling (1975) 

 stated: "Unlike kelp perch, senoritas did not 

 exploit the plankton as a major source of food." 

 Although this view would seem to disagree with 

 our findings, their samples of the two species were 

 not comparable on this point. Most of their kelp 



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