LOVE and EBELING: FOOD AND HABITAT OF THREE FISHES 



Table 2. — Percent total volume and frequency of occurrence of 26 food items in stomachs with food of the three species of 

 kelp-bed fishes in the 151- to 300-mm size group (Table 1, Figure 1) from Naples Reef or One-Mile Reef (olive rockfish only) 

 off Santa Barbara, Calif Food items are listed by general characteristics and presumed major dajftime source. A tr 

 indicates unmeasurable trace; a dash indicates none. 



Primarily planktonic (Sum =) 

 Small crustaceans (0.5-5 mm long): 



Ostracods 



Cladocerans 



Zoea larvae 



Cope pods 



Megalops larvae 

 Large crustaceans ("^10 mm): 



Euphausiids 



Pleuroncodes 

 Small-medium sized, transparent 

 (1-10 mm): 



Eggs 



Chaetognattis 

 Tunicafes (small salps. 

 larvaceans) 

 Large, transparent (^^15 mm): 



Siptionophores. medusae, etc. 

 Fish larvae (5-15 mm) 

 Primarily nektonic (20-80 mm) (Sum = 

 Fish 

 Squid 

 Ectoparasites of other fish: 



Parasitic copepods 

 Primarily substrate oriented (Sum =) 

 Free moving animals: 

 Crabs 

 Shrimps 

 fwlysids 

 Isopods 



Gammaridean amphipods 

 Caprellid amphipods 

 Hyperiid amphipods « 



Polychaete worms ' 



Hydroids 

 Kelp, etc.: 

 Kelp (including encrustfng 



bryozoans) 

 Other algae (including 

 encrusting bryozoans) 



Total volume of food 



consumed (ml) 

 Total number of specimens 



examined 



(56.7) 



0.6 

 0.2 

 0.6 



0.6 

 1.9 



51,5 



0.7 

 0.6 



(15.7) 

 7.4 

 8.3 



(27.5) 



0.3 

 0.2 

 1.6 

 0.1 

 0.1 

 0.3 

 13.1 



10.5 

 1.3 



171.2 



20.9 

 22.4 

 11.9 



1.5 



1.5 

 10.4 



40.3 



4.5 

 10.4 



13.4 

 3.0 



6.0 

 3.0 



17.9 

 1.5 

 1.5 

 1.5 



16.4 



25.4 

 9.0 



67 



(12,6) 



0.3 

 1.5 

 0.1 



2.5 



7.8 



0.4 



(55,3) 



51.0 



4.3 



(32.3) 



0.8 

 0.7 

 0.5 

 0.2 

 2.2 

 7.5 



0.4 

 8.7 



8.8 

 2.5 



141.3 



6.0 

 7.5 

 3.0 



1.5 



16.4 

 1.5 



46.3 

 6.0 



3.0 

 1.5 

 9.0 

 1.5 

 13.4 

 13.4 



7.5 



16.4 



16.4 

 14.9 



67 



(10.5) 



0.3 

 0.3 

 2.6 



0.1 



5.4 



2.9 



15.1 

 15.1 

 24.7 



2.7 



6.8 



20.5 



(41.8) 



1.4 



85.8 



0.1 



102.9 



14.3 



1.4 



73 



72 



species (Table 2), fish with empty guts and of sizes 

 outside the middle range of 151-300 mm SL (Ta- 

 ble 1, Figure 1) were excluded. 



To test for communal switch feeding and dietary 

 consistency, we examined variation among indi- 

 viduals. We counted fish that contained mostly 

 one food item or prey type and that 1) were of one 

 species collected on the same day, 2) were of all 

 three species collected on the same day (Table 3), 

 and 3) were of all species collected at any time 

 (Table 4). 



To examine seasonal variation in diet, stomach 

 contents of each species were pooled by seasonal 

 periods that correspond roughly to different 

 oceanographic regimes off Santa Barbara. Brown 

 (1974) concluded that in the Santa Barbara Chan- 

 nel, cooling of surface water typically proceeds 



from December to July, first by surface mixing and 

 small-scale upwelling associated with storms from 

 December to April, then by large-scale upwelling 

 from May through July. This precedes gradual 

 surface warming from late June to December, 

 with strongest thermal stratification and clearest 

 water from August to December. Therefore, we 

 delimited seasonal periods as: 1) December- 

 February, a period of winter storms and the be- 

 ginning of vertical mixing and surface cooling ( in- 

 itial breeding season of many species); 2) March- 

 May, a period of most intense upwelling of deep 

 cold water (high surface productivity, zooplankton 

 blooms, appearance of young-of-the-year fish, 

 etc.); 3) June-August, a period of decreasing up- 

 welling and the beginning of thermal stratifica- 

 tion and surface warming (a transitional period); 



259 



