9-9 



These hypotheses were indirectly addressed with respect to the 

 entire data set (1971-1977) by means of graphic comparisons between 

 stations and between years (Figures 9-3, 9-4 and 9-5). This was espec- 

 ially important for hypotheses 2 and 3 where the nature of the data 

 precluded the inclusion of preoperation results in the formal hypo- 

 thesis testing (see Statistical Appendix) . 



RESULTS 



Table 9-1 gives mean length, dry weight, dry weight condition 

 index, wet weight condition index and cavity volumes for control and 

 experimental oysters from 1973 - 1977, while Figure 9-3 graphs dry 

 weight condition index of control and experimental oysters for the same 

 time period. These summary data are presented for perspective and . 

 to temporarily extend the results of hypothesis testing. 



Mortality 



Figure 9-4 graphs percent survival of oysters by month from 

 1973 to 1977, while Table 9-2 presents the data with summary statistics 

 from which these graphs were developed. These data show that percent 

 survival (the complement of percent mortality) appeared similar in all 

 years (range 80-96%) except 1975 when percent survival dropped to 67- 

 69%. 



Table 9-3 displays oyster mortality data from 1974-1977. 

 These data were used to test hypothesis (1) , with regard to differences 

 in mortality attributable to station and year. Table 9-4 presents the 

 results of hypothesis testing for mortality versus year and station, and 

 Table 9-5 presents the results of a pairwise comparison of years, two 

 years at a time. The results shown in Table 9-4 indicate that oyster 

 mortality was independent of station but dependent upon year. The 

 mortality by station by year interaction was not significant. The 



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