7-21 



heterogeneity in the fauna of the expansive Long Wharf intertidal flat. 

 At Norwalk, Connecticut, Gemma gemma, Ilyanassa obsoleta , Mya arenaria , 

 and Scoloplos acutus were most numerous (NAI, 1974) . At Stamford Harbor 

 the most numerous fauna were Mya arenaria , Ilyanassa obsoleta , Nereis 

 succinea, and Spionidae (NAI, 1974). A Bridgeport Harbor study (NAI, 

 1973) indicated that Nereis arenaceodonta , Scolecolepides viridis , 

 and Spio setosa were the most ubiquitous of the polychaetes, that the 

 wide-ranging molluscs were Ilyanassa obsoleta, Mya arenaria and Gemma 

 gemma, and that Limulus polyphemus was the most prevalent arthropod. 



Other community parameters, such as seasonal species richness 

 and abundance were variable between New Haven Harbor and other areas. 

 In the current New Haven study, species richness and abundances were 

 generally greatest in the October sample period, due to spring and 

 summer recruitment. Cunningham's data also indicated high summer abun- 

 dances in 1972 and; 1973. At Stamford (NAI, 1974) sampling in July and Octo- 

 ber showed that samples taken in August 1971 and January, February, March 

 and May of 1972 at low and mid-intertidal stations in Bridgeport yielded 

 maximum summer species richness, but abundances were greatest in the 

 winter, due to high year-round populations of polychaetes and bivalves 

 (NAI, 1973) . 



ANALYSIS OF IMPACT 



The purpose of the seven-year monitoring program was to detect 

 any direct or indirect impacts of the United Illuminating Company gener- 

 ating station on the fauna of New Haven Harbor. The condenser-cooling 

 system of New Haven Harbor Station is a potential source of impact on 

 the intertidal fauna of the harbor. In general, the use of estuarine 

 and oceanic water in power station cooling systems has resulted in high 

 rates of invertebrate and fish larval mortalities for those entrained 

 (Enright, 1977). However, Enright (1977) suggested that, due to high natu- 

 ral excesses of larvae produced, larval mortality from entrainment may not 



significantly influence adult settling populations. 



