7-10 



at East Shore in October 1973 and 1977 and at Long Wharf in October 1974 

 and 1977 (Figure 7-2) . 



Although variable, no trends were apparent in annual species 

 richness values, except a slight increase from 1971 to 1977 (Table 7-4) . 

 seasonal trend was fairly consistent: generally, richness was greater 

 in fall than spring, related to spring/summer recruitment and winter 

 "die off". The greatest number of species occurred at Sandy Point, 

 possibly related to its protected nature as discussed above, and its 

 proximity to cleaner, outer harbor waters. Lowest species richness 

 occurred at East Shore for most years and overall. 



Ten taxa were selected as overall dominants whose distribution 

 at particular stations was fairly consistent (Table 7-1) . At East Shore, 

 fauna were sparse in May, except for moderate numbers of annelids and 

 molluscs. In October, Mya arenaria, Balanus improvisus and Nereis 

 succinea were abundant for four out of seven years, and Limulus poly- 

 phemus for three (Table 7-6) . At Sandy Point, Ilyanassa obsoleta was 

 abundant in spring/fall for most years and Gemma gemma for the first 

 three years and spring 1974 (Table 7-7) . At Long Wharf Mya was the main 

 dominant, with Nereis occurring in lesser numbers for most years (Table 

 7-8). Of the dominant species, four appeared in all sample periods: 

 Nereis succinea, Mya arenaria, Ilyanassa obsoleta, and Gemma gemma. 



Dorrtinant Species 



Population densities of dominant species in New Haven Harbor, 

 as indicated by the sampling program, are presented by station and month 

 in Tables 7-6 through 8. Most species showed trends in spatial and 

 temporal distribution. The eight highest ranked species (Table 7-2) are 

 discussed in some detail below. 



The soft-shell clam [Mya arenaria) was the most numerous 

 bivalve sampled in the New Haven Harbor intertidal community (Figure 7-2) 



Text continued on page 7-15 



