TABLE I. Number of species (S), number of individuals (N) and percentage of the total (%) for each 

 major taxon collected at Millstone intcrtidal stations September 1985 - June 1987, with ranges from 

 1980 -1985. 



of the range. Thus at WP, the overall contribution 

 of rhynchocoels increased, accounting for 59-68% 

 of the total organisms in 1986-87 versus a maxi- 

 mum of 40% during the pre-operational period. 

 In 1986-87, polychaetes continued to be the major 

 component at GN, and there were no major 

 changes relative to 1980-85. 



Community Abundance 



Quarterly mean abundance with multiple regres- 

 sion predictions, and adjusted annual mean abun- 

 dances of the three intertidal communities are 

 plotted in Figures 3 and 4, respectively. Abun- 

 dance (exponentials of values in Figure 3) during 

 1986-87 ranged from 4 - 95/core at GN, 23 - 

 701 /core at .IC and from 3 - 62/core at WP. In 

 both 1986 and 1987, strong seasonal peaks were 

 evident at .IC and WP in June, while at GN 

 densities peaked in either June or September. 



When compared to previous years, abundances 

 at JC during 1986-87 were within the range ob- 

 served in past years. At WP, 4 of the 8 quarterly 

 means obtained since September 1985 were at or 

 below the extremes observed during 1980-85. 



The multiple regression analyses indicated that 

 there have been no increasing or decreasing trends 

 in community abundance at any of the intertidal 

 stations since 1980. In addition, comparisons of 

 annual means (t-tests) revealed few significant dif- 

 ferences among comparisons involving 1986 or 

 1987. The 1986 abundance at JC was significantly 

 different from only 1982, while 1986 at WP was 

 significant from 1980 and 1984. At GN, 1986 and 

 1987 abundances were not significantly different 

 from any of the previous years. 



66 



