During 1983, community densities were well within the range of those 

 obtained in past years. Densities at IN, although varying within any given 

 year, have been generally consistent since 1976. At EF , GN and JC, peak 

 densities occurred in 1979-80, but since then, have exhibited fairly stable 

 levels of abundance between years. 



Biomass 



Average biomass (ash-weight) of subtidal communities in 1983 ranged 

 from 0.01 g/core (IN) to 0.04 g/core (EF) (Fig. 12). Over the four 

 sampling periods, biomass fluctuated most at IN and least at JC. These 

 within year fluctuations did not consistently follow patterns of abundance. 

 In nearly all cases, periods of peak biomass corresponded to high densities 

 of arthropods and molluscs, organisms that are typically large relative to 

 annelids. During 1983, biomass exhibited less variation (except IN) than 

 in the previous years, and all values were well within the ranges typically 

 observed at our monitoring stations. 



Communi ty Dominance 



At all stations, except IN, the ten most abundant organisms accounted 

 for over 80% of all the organisms collected (Table 8) , Oligochaetes and 

 Aricidea catherinae were the only taxa among the top 10 at all stations and 

 together comprised from 32.4% (IN) to 68.4% (JC) of the individuals 

 identified during 1983. Polydora caulleryl , Chaetozone spp., and Tharyx 

 spp, were among the dominants at all but the IN station. 



Densities of individual taxa were highest at the JC station where 

 oligochaetes (Ill/core) and A_. catherinae (64/core) were most abundant. At 

 IN, even the most abundant organism, Ampelisca verrilli , occurred in 

 relatively low densities (11 /core). Beyond the top two or three taxa, each 

 of the subtidal communities included some organisms that were dominant 

 components only at single station. Polycirrus eximius and Protodorvlllea 

 gaspeensis were important components at EF, Tharyx spp. at GN , A. verrilli 

 and F.xogone hebes at IN, and £. caulleryi and Mediomastus ambiseta at JC. 



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