518 



Fishery Bulletin 88(3), 1990 



LU 

 O 

 CO 

 LU 

 Q. 



El Nino 

 1983 



1981 : 1982 



1983 



El Nino 



1984 



1985 1986 



>5 Prey Taxa 



= (= 5.E5IS Q.E5 

 <i5 "''rn "iS ".5 < 



1985 



1986 



Figure 8 



Seasonal occurrence of single and multiple 

 prey taxa found in 1304 California sea lion 

 scats. 1981-86. No samples were collected in 

 winter 1986. 



The relative frequencies of different prey taxa per 

 scat varied among seasonal sampling periods during 

 the study period (Fig. 8). Relative frequencies of prey 

 taxa per scat for years 1982-85 were the same for all 

 seasons in 1983 (x" = 22.067, df = 15, P = 0.1061) and 

 1985 (x-= 18.219, df=15, P = 0.2513), but greater 

 numbers of prey taxa were found in scats in 1982 

 (x- = 35.892, df=15, P = 0.0018) and 1984 

 (X^ = 44.046, df = 15, P = 0.0001). 



Discussion 



California sea lions using SCI consumed a variety of 

 prey, consisting primarily of fish and cephalopods as 

 indicated by the presence of fish remains in 98.5% of 

 the scats and cephalopod remains in 35.5% of the scats. 

 They fed on schooling fishes (e.g., northern anchovy, 

 jack mackerel, Pacific mackerel, Pacific whiting, black- 

 smith, and rockfish), schooling cephalopods (e.g., mar- 

 ket squid; Hurley 1978), and pelagic crustaceans that 

 drift in large swarms (e.g., pelagic red crab; Boyd 

 1967). Our temporal analysis of nine prey taxa in- 



