7-4 



2 



Species were analyzed for abiindance (#/in ) and frequency of 



occurrence (percent occurrence) . High percent occurrence (number of 

 sample iseriods a taxon was present divided by total number of sample 

 poriods) was used to identify species that were consistently present, 

 includint) those that W(!rc low in abundance. Abundant taxa wore those 

 wlii.ch characterized a station, based on their higher relative abundances 

 in samples (Table 7-4) . Overall dominance (common taxa) was determined 

 by ranking all taxa collected both by frequency of occurrence in samples 

 over seven years and by total abundance over the same period. Rank 

 scores were assigned to taxa on both lists (i.e., the taxon ranked first 

 was given a score of 1, second ranked 2, etc.). Scores for each taxon 

 were added from both lists and the lowest 10 scoring taxa were desig- 

 nated as dominant (Table 7-1) . Species richness (total number of taxa) 

 was used as a measure of diversity for a given station or year. 



Obvious constraints are imposed upon interpretation of results 

 by the complexity of the intertidal environment as well as the temporally- 

 limited (semi-annual) sampling regime. The abbreviated sampling regime 

 was selected because of the minimal plant operational impact anticipated 

 in the intertidal area; spring and fall sampling were most likely to re- 

 flect any changes in faunal overwintering success and recruitment. 

 Knowledge of unrecorded interim events would have simplified interpre- 

 tation of the data; nonetheless it is clear that any major changes in 

 the community habitat would have been evident. 



CHARACTERIZATION OF NEW HAVEN HARBOR INTERTIDAL FAUNA 



During the seven-year period of biological monitoring along 

 intertidal transects in New Haven Harbor, a total of 90 invertebrate 

 taxa and 6914 individuals were collected (Table 7-1) . Of the 90 taxa, 

 22 were represented by only one or two individuals, and 60 taxa were 

 found in either one (35 taxa) , two (18 taxa) or three (7 taxa) sample 

 sets. Samples taken at a given station in a single month and tidal 

 period were considered a sample set. Mya arenaria. Nereis succinea. 



