Liver Microsomal Enzyme Activity/Plasma Steroid Hormones/Reproductive Success 

 (January-February). Differences among sites were difficult to detect with the fish from the 

 second collection, since relatively few fish were caught at each site. AHH activity was 

 similar among fish from the three sites (Table 26). Mean testosterone concentrations in BK 

 fish were about one-third those in SC fish. Estradiol concentrations were similar among 

 sites. There was a consistent pattern of lower measures of reproductive success in fish from 

 BK compared to those from SC. The difference between site means was about three fold for 

 percent embryological success, but within-site variability was high. 



Blood Erythrocyte Micronuclei. The mean number of micronucleated erythrocytes in all 

 fish (both sampling periods) was lowest in fish from the coastal sites (SC and RR) compared 

 to those from the four sites in San Francisco Bay (Table 27). The counts were highest in fish 

 from the VJ and BK sites. OK and SP fish had similar mean values. Variability within 

 each site was high, especially in the fish from BK and OK, where the standard deviations 

 exceeded the means. The proportion of fish with zero micronucleated cells was highest in 

 the fish from the SC and RR sites and lowest at the VJ, SP, and BK sites. 



In the November-December collection, the mean incidence of micronuclei was distinctly 

 lower in the fish from RR (Table 27). No detached micronuclei were found and 77 percent of 

 the cells had no micronuclei in the RR fish. The highest mean incidences of total and 

 detached micronuclei were in BK, VJ, and SP fish; whereas, the highest mean incidences of 

 attached micronuclei were in OK and BK fish. 



The incidence of nuclear pleomorphism (loss of the usual elliptical shape of the 

 nucleus) was also recorded in each fish. The percent of the fish with this condition was 

 highest in fish from BK and OK, lower in fish from SP, and lowest in fish from VJ, SC, and 

 RR (Table 28) 



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