5-43 



nant species showed changes in distribution or abundance that could be 

 related to station operation. Three previously unrecorded species at 

 Harbor Station and other stations were found in 1976: Rithropanopeus 

 arrissi, Eteone heteropoda and Euplana gracilis. Numerous other species 

 have been variable in occurrence (Table 5-8) . 



The study conducted at Bridgeport Harbor 1971-1972 (NAI, 1973) 

 did not discern any effect of thermal effluent on faunal composition. 

 The difference between control and effluent station temperatures was 

 11°C (March-August 1971) . The most obvious effect was the month-earlier 

 settlement of most species in the effluent. Species present are listed 

 in Table 5-6. Faunal diversity was greater at the discharge than the 

 control; this is the opposite of the result at the Piscataqua River 

 estuary in New Hampshire and Millstone Harbor where the immediate dis- 

 charge area was lower in diversity (NAI, 1977a; Battelle, 1977). In 

 addition, at Millstone, a subtropical species. Teredo bartschll , has 

 occurred regularly in the effluent since 1975. 



Careful examination of potential modes of electrical gener- 

 ating plant impact indicate that there has been no measurable effect on 

 New Haven Harbor Station fouling communities. 



SUMMARY 



A total of 75 species and numerous higher taxa were identified 

 from New Haven Harbor exposure panels during the sampling period August 

 1971-October 1977 (Table 5-8) . The dominant species were the barnacles, 

 Balanus eburneus and B. Improvisus , the hydroid, Obella longlsslma, the 

 amphipod, Corophlum Insldlosum, the polychaete, Polydora llgnl, the 

 mussel, Mytilus edulls , and the ship borer. Teredo navalls . Spatial 

 trends in species richness were evident within the harbor. Species 

 richness at Fort Hale and Harbor Station, was higher than at Long Wharf 

 for most years. General seasonal trends in species richness were not 

 consistent. The maximum number of species occurred in either spring. 



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