Quarterly numbers of species, total numbers of individuals and relative abundances from September 

 1979 to March 1986, for each major taxon collected at intertidal stations are presented in Appendix I. 

 Highest abundances of polychaetes and oligochaetes generally occurred in September or June. Molluscs 

 and arthropods, more common in the JC community, have also been most abundant in either September 

 or June. Rhynchocoels, an important component of the GN and WP communities, were generally most 

 abundant in colder months (December and March). 



In the three 1986, sampling periods (September/ December 1985 and March 1986), there were 

 temporal shifts in general community composition evident at all intertidal stations. For instance, 

 polychaete species number at WP and GN stations was lower than all previous observations in the 

 September collections. The total number of individuals at WP in September was lower than most 

 previous observations. The GN and WP stations also had relatively low total numbers of individuals 

 in December and March collections, lower numbers of polychaete species and total numbers of species 

 in the December collections. Although the three JC sample periods were similar to most previous 

 sampling periods, the total number of individuals in December was sightly lower. The JC 1986 March 

 collection was among the highest for total numbers of species and individuals recorded for that period. 



Community Dominance 



Since 1980, intertidal communities have been numerically dominated by species of polychaetes, 

 oligochaetes and rhynchocoels, and during this period, only one one arthropod {Gammarus lawrencianm) 

 and one mollusc {Gemma gemma) species have accounted for more than 5% of the total individuals 

 collected (Table 3). Only Scolecolepides viridis, Polydora ligni, and oligochaetes were among the 

 dominants at all stations. At GN and WP, 9 of 10 numerical dominants were the same over the 

 baseline period. In contrast, six of the top ten most abundant taxa at JC were dominants at only this 

 station. 



Sandy beach communities in the Millstone Point area were typically comprised of a few taxa that 

 occurred in high densities over all sampling years, along with less abundant forms that exhibited temporal 

 variations over the monitoring period. This was particularly true at JC, where oligochaetes accounted 

 for over 60% of all individuals in 5 of the past 6 years and was the most abundant taxon in each of 

 the last six sampling years (BIV= 100%). Scolecolepides viridis and Hediste dtversicolor were the orily 



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