chovy, Engraulis monto (Engraulididae); white 

 croaker, Genyonemus lineatus (Sciaenidae); 

 queenfish, Seriphus politus (Sciaenidae)] are 

 among the most abundant adult fishes in the 

 area, and are important links in the local trophic 

 structure. The northern anchovy is important as 

 forage for larger fishes and is fished commer- 

 cially for manufacture of fish meal and oil. While 

 the two sciaenid species have less commercial 

 value, both are important as forage for larger 

 species. 



Materials and Methods 



Samples were collected as part of a program of 

 preoperational environmental studies at San 

 Onofre Nuclear Generating Station (Fig. 1). In 

 the area near the generating station (designated 

 "treatment"), two transects extended over depths 

 of 8 to 11 m and 12 to 15 m. Transects were also 



located in a "reference" area 5.8 km northwest. 

 The two areas are similar in bottom topography 

 and in the presence of a kelp bed just south of the 

 outer transects. Each transect was 760 m in 

 length. The two treatment transects and the two 

 reference transects were each separated by 150 

 m. Monthly collections were made every 30±2 d 

 from March 1978 through July 1979. Results for 

 March through July samples for 1978 and 1979 

 are presented as mean values for the 2 yr com- 

 bined. 



Three vertical water column levels were sam- 

 pled. The neuston was sampled, using a Manta 

 net (Brown 1979). This net has a rectangular 

 mouth (86 cm X 15 cm) and is designed to sample 

 the upper 14 cm of the water column. The net fil- 

 tered a volume of approximately 100 m 3 during 

 each tow. 



Midwater samples were taken with paired 

 opening-closing 60 cm diameter circular bongo 



SANTA BARBARA 



LOS ANGELES 



PACIFIC 



OCEAN 



/ 



SAN ONOFRE 

 1 NUCLEAR GENERATING 

 STATION 



^o 



*S 



METERS 



500 IOOO 2000 



DEPTH IN FEET 



Figure 1.— Location of sampling sta- 

 tions offshore San Onofre Nuclear Gen- 

 erating Station ("treatment") and San 

 Mateo Point ("reference"). Inset locates 

 the area in relation to southern Califor- 

 nia. 



896 



