Composition and Distribution of Macrobenthic Invertebrate Fauna 



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NOV* GULF OF GEORGES SOUTHERN GEORGES SOUTHERN 



SCOTIA MAINE BANK NEW ENGLAND SLOPE NEW ENGLAND 



SHELF SLOPE 



GEOGRAPHIC AREA 



Figure 70 

 Density and biomass of Annelida in each of the six geographic areas. 



Geographic Distribution 



Annelid worms were found in all parts of the study area 

 (Fig. 69). Only the Mollusca, Crustacea, and Echino- 

 dermata compare with their widespread distribution, 

 and only the Crustacea are more numerous. 



The density of annelids on the continental shelf and 

 slope generally averaged between 100 and 1,000 indi- 

 viduals/m 2 . Over approximately 10% of the shelf and 

 slope area, the density of annelids was high, 1,000 to 

 12,000/m 2 . About 30% of the shelf and slope area 

 yielded less than 100/m 2 . In deepwater regions beyond 

 the continental slope, the density was relatively low, 

 usually less than 100/m". 



The biomass of annelid worms on the continental 

 shelf and slope, with few exceptions, averaged between 

 1 and 50 g/m 2 and reached a maximum of 325 gm-'. 

 Among the six standard geographic areas, two slope 

 areas (Georges Slope and Southern New England Slope) 

 had the lowest numerical density and smallest biomass 

 of annelids, 80 to 149 individuals/m 2 and about 4 to 5 

 g/m 2 (Tables 6-9; Fig. 70). 



In the four continental shelf areas the numerical den- 

 sity of annelid worms was high. Average densities ranged 

 from 291 to 648 individuals/m and greatest density was in 

 the Nova Scotia area. Biomass in these areas, also, was 

 moderately high; average values ranged from 8 to 30 g/ 



