FISHERY BULLETIN: VOL. 74, NO. 3 



Figure lO.-A solitary walleye surfperch, Hyperproaopon argen- 

 teiim, swims in the water column at night. 



was empty; the rest were full of prey, much of it 

 fresh. 



Clearly, this is a nocturnal fish. Those seen in the 

 study area at night, however, tended to be smaller 

 on the average than those seen in the diurnal 

 schools, suggesting that the larger fish might 

 range farther away. All prey in the 34 individuals 

 containing identifiable material were organisms 

 that occur in the water column, as listed below. 



3. ISOPODS (72: 21.1: 10.2) 



Paracercies sp. (65: 19.5: 7.6); gnathiid juveniles (21: 1.0: 0.6); 

 Pentidotea resecata (15: 0.2: 0.6); Excorallana kathae (3: 0.1 

 1.0); Cirolana diminuta (15: 0.2: 0.2); Rocinella belliceps (6: 

 <0.1: 0.2); ExoRpheroma sp. (6: <0.1: <0.1); idoteid sp. (3: <0.1 

 0.1). 



4. CAPRELLID AMPHIPODS (41: 2.1: 6.0) 



Caprella pilidigita (24: 1.4: 4.7); C. caUforn tea (21: 0.7: 1.2); C. 

 penantiK (3: <0.1: <0.1); Tritella laevis (3: <0.1: <0.1). 



5. POLYCHAETES, SWIMMING (35: <0.7: 6.4) 



epitokous nereids (9: 0.7: 5.5); unidentified fragments (26: ?: 

 0.9). 



6. OSTRACODS (62: 1.7: 1.6) 



Paraatvrope sp. A (38: 0.7: 0.6); Ciichleberia lohiancoi (23: 0.5: 

 0.4); Philomedef! sp. (9: 0.4: 0.4); species (3: <0.1: <0.1); 

 species N (3: <0.1: <0.1). 



7. MYSIDS(21:0.6:1.3) 



Siriella pacifica (15: 0.5: 1.2); Acanthomysis sculpfa (3: <0.1: 

 <0.1); unidentified fragments (3: 0.1: <0.1). 



8. CARIDEAN ADULTS AND JUVENILES (21: 0.9: 0.9) 



Hippolyte clarki (3: 0.2: 0.1); unidentified (24: 0.7: 0.8). 



9. BRACHYURAN MEGALOPS (26: 0.7: 0.5) 



unidentified. 

 TANAIDS(15:0.5:0.5) 



Leptochelia duhia (6: 0.2: 0.3); unidentified (9: 0.3: 0.2). 

 NEBALIACEANS (6: <0.1: <0.1) 



Nebalia ptigettensis. 

 CARIDEAN LARVAE (3: <0.1: <0.1) 



unidentified. 



10 



11 



12 



1. GAMMARIDEAN AMPHIPODS (100: 63.6: 47.0) 



Bafea transversa (85: 39.8: 24.2); Am pit hoe spp. (41: 3.3: 3.8); 

 Hyale nigra (9: 2.8: 2.9); Ericthonias braziliensis (15: 0.5: 

 1.1); Ampelisca sp. (15: 0.6: 1.0); Synchelidium sp. (24: 0.4 

 0.3)rlysianassid spp. (15: 0.6: 0.2); Heterophilias seclusus (6 

 0.1: 0.1); Photis sp. (3: <0.1: 0.1); Paraphoxus sp. (3: <0.1 

 <0.1); Aoroides colu mbiae (3: <0.1: 0.1); unidentified (91: 15.4 

 13.2). 



2. CUMACEANS (85: 52.9: 25.2) 



Cyclaspis nubila (76: 51.2: 24.8); Cumella sp. A (18: 1.7: 0.4). 



B rachyistius frenatus— kel p perch 



The kelp perch, which Miller and Lea (1972) 

 claimed can attain a length of 214 mm, was 

 numerous close among the rising stands of giant 

 kelp. It often aggregated immediately under the 

 canopy (Figure 11), but occurred along the entire 

 length of the plants from water's surface to the 



Figure 11. -Kelp perch, Brackyistius 

 frenatus, aggregated close to kelp, 

 pluck zooplankters from the water 

 column during the day. 



588 



