6-55 



between preoperational and postoperational species richness (t= 

 .4285, 0.5 < p < 0.9). Because late summer appears to be the period of 

 greatest stress for populations in the harbor, the species richness data 

 for August of 1974 were compared and paired by station, with similar 

 data for 1975, 1976 and 1977. In all cases, results were not signifi- 

 cant, indicating no decrease in summer species richness after operation 

 of New Haven Harbor Station commenced. 



Species Riahness 



The primary factor limiting the application of statistical 

 analysis to the New Haven Harbor benthic data is the large degree of 

 variability. The results of the three-way ANOVA to test the impact of 

 year, season and station on species richness and faunal density indicate 

 that all three factors and their interactions were significant (p < 

 .001) for all parameters, with the exception of season vs. station. 

 Numbers of taxa for each station-season combination were examined for 

 significant differences between preoperational and postoperational data. 

 For two of these comparisons (Station 8, spring; Station 13, summer) the 

 results were significant, with greater numbers of taxa postoperationally 

 at Station 8 and greater niombers of taxa preoperational ly at Station 13. 

 Because the transformation procedure was not successful in eliminating 

 heteroscedasticity (unequal variance) for the faunal density data, and 

 the overall results of the ANOVA indicate an apparently patternless 

 variability, these contrasts were not analyzed for numbers of individ- 

 uals. These results are indicative of a system with large and extremely 

 variable changes in its faunal structure in both time and space. The 

 only meaningful statistically significant relationship concerning spe- 

 cies richness was that between the inner harbor and Morris Cove. The 

 preoperational and postoperational species richness data were compared 

 for inner harbor stations vs. Morris Cove stations and paired by sam- 

 pling period. In both cases Morris Cove was found to contain signif- 

 icantly more species than the inner harbor (preoperational, t = 4.5134, 

 p < .001; postoperational, t = 5.628, p < .001). 



