density does vary substantially in both these regions and the 

 submersible obviously did not cover the exact dredge path. 

 Nevertheless, the level of agreement, even if somewhat serendipi- 

 tous, is worthy of comment. In contrast to this high level of 

 agreement between dredge and submersible comparisons, Caddy 

 (1968, 1971) reported much lower scallop drag efficiencies 

 ranging from 0.69 to 42.4% in a much more rigorous comparative 

 submersible/ dredge study. 



On the Richibucto grounds, Gulf of St. Lawrence, Caddy 

 (1970) found that the scallop densities varied over the course of 

 a dive track similar to the results reported here (see Figure 3). 

 Caddy (op. cit. ) tested the population distribution for depar- 

 tures from randomness and found the distribution to be contag- 

 ious. On the scallop beds we studied the results are similar; 

 scallops show a clustered distribution even at the lowest density 

 observed. Our data was further analyzed to test for a model that 

 adequately described the population structure. For both high and 

 low density areas (i.e., Fippennies Ledge and Jeffreys ledge) a 

 negative binomial model gave the best fit to the data (Figures 4 

 and 5 ) . 



Faunal associations at the three study sites in the western 

 Gulf of Maine are very similar with three invertebrates being 

 clearly recognized as dominant. The association between these 

 three animals (the sea scallop, myxicolid worms and cerianthid 

 anemones) is significant on Fippennies Ledge but is not as 

 clearly defined at the other two sites. Ecologically the 

 significance of these associations is not yet understood. The 

 scallop and myxicolids are both suspension feeders, preying on 

 similar sized particles (Dales, 1957; MacDonald and Thompson, 

 1985) while the cerianthids are carnivorous passive suspension 

 or impingement feeders ( Shepard et al., 1986). All three animals 

 would require adequate currents and suspended material for 

 feeding. Food availability may therefore be an important factor 

 in the co-occurrence of these populations. Sediment type may 

 also be important but detailed grain size analysis, organic 

 content determinations, etc., are only now being done for the 

 1987 samples. As far as scallop occurrence is concerned 

 observational data on sediment type has shown that scallops are 

 most abundant on the more sandy substrates. Caddy (1970) also 

 observed the highest density of scallops on sand rather than mud 

 substrates. 



Caddy and Carter (1984) evaluated faunal adjacencies on 

 scallop grounds in the lower Bay of Fundy. Comparison of their 

 faunal list from the eastern Gulf and ours from the western Gulf 

 show a high degree of species overlap but a lower level of 

 diversity (55 species in the east vs 26 in the west). However, 

 further data collection and analysis, through 1987, may expand 

 our species list. What is most interesting is that different 

 species, apart from scallops, are dominant in the two regions. 

 For example, Myxicola , our numerical dominant, does not occur in 

 Caddy and Carter's faunal list although Myxicola ' s range includes 



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