Long-Term Population Densities 



The abundances of the top four infaunal taxa collected at each 

 Millstone subtidal station during 1983 were examined to identify seasonal 

 patterns of abundance and station-specific or area-wide trends in density 

 that have occurred during the past six years. 



Oligochaetes 



Oligochaetes are small, deposit-feeding worms that feed on fine bottom 

 deposits. During 1983, oligochaetes ranked first in abundance at JC and 

 EF, second at IN and fourth at GN. This taxon was among the top four 

 dominants at all subtidal stations and have been among dominant infaunal 

 organisms collected at all monitoring stations since 1976. Oligochaetes 

 have typically been most abundant at JC and least abundant at IN. During 

 the last six years, no seasonal trends have been evident at any of the 

 stations (Figs. 13 A-D) . Year-to-year densities have been most stable at 

 IN, where lowest abundances occur. During the last two years, densities at 

 both JC and EF have also remained quite stable while those at GN have 

 exhibited a gradual decline in abundance. 



Arlcidea catherinae 



Aricidea cath erinae is a small deposit-feeder that occupies a wide 

 range of habitats and is subsequently a common member of many subtidal 

 communities. Despite its widespread abundance, surprisingly little is 

 known about its food preferences, reproductive strategy, and function 

 within marine communities. 



During 1983, Aricidea ranked first in abundance at GN, second at EF 

 and JC, and third at IN; this species was the only taxon other than 

 oligochaetes that was among the top four at all subtidal stations. 

 Aricidea has consistently been among the top ten taxa at all stations since 

 1976, despite the strong within and between-year fluctuations in density 

 that have occurred at all stations (Figs. 13 E-H) . On a seasonal basis, 

 peak densities often occurr in September or June, although peaks have 

 occured in all seasons. The abundance of Aricidea has been most 



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