On the sandy substrate these anemones were often observed 

 attached to a rock outcrop or loose boulder rather than directly 

 on the sand itself. Pandalid shrimp were found on sandy-silt 

 while the sea scallop, Placopecten , was primarily restricted to 

 sand. The asteroid starfish which include a variety of genera 

 and species (e.g., Asterias , Hippasteria , Henricia , Crossaster , 

 Solaster ) occur over a broad range of substrate types. They are, 

 however, more prevalent on the coarser grained substrates and 

 virtually absent on clay. In contrast, ophiuroids do not occur 

 on gravel substrates in any numbers while they are the dominant 

 species group on silts and clays. The only fish species that 

 occurred in sufficient numbers to demonstrate any substrate 

 specificity was the silver hake Merluccius bilinearis . This 

 species was observed resting on the bottom on silty sand and 

 finer sediments. 



DISCUSSION 



This study is the first, broadscale, macrobenthic survey in 

 the Gulf of Maine using manned submersibles. The 

 characterization of the benthos that emerges from this work is 

 surprisingly simple. Relatively few taxa, or taxonomic groups, 

 from two phyla dominate the benthos on a numerical basis (Table 

 1, Figure 2). It's interesting that these phyla ( Echinodermata 

 and Cnidaria) are different from the dominants found by Emery et 

 al. (1965), (Arthropoda and Annelida) in their survey using 

 surface deployed sampling gear. Obviously both temporal and 

 spatial scales can account for some of these differences; Emery's 

 stations extended well beyond the confines of the Gulf of Maine 

 and predates the present work by twenty years (compare Figure 1 

 with Emery et al's. Figure 3). In a more detailed evaluation of 

 the same database Theroux and Wigley (MS, in prep. ) found that in 

 the Gulf of Maine, per se, molluscs, annelids and crustaceans 

 were the three numerically dominant groups. Echinoderms were 

 fourth in abundance with ophiuroids accounting for the majority 

 of this group. Again, the differences between the studies, even 

 with reduced spatial variability, is substantial. It is 

 unlikely, however, that climatological changes over twenty years 

 would account for these differences. It is more likely sampling 

 methodology, quantitative grabs vs photographs, generated the 

 differences. Grab sampling would be expected to produce samples 

 containing higher numbers of molluscs and annelids whereas 

 photographs highlight the epibenthic organisms. One might expect 

 more overlap between the two databases with groups like the 

 crustaceans but, again, the sampling methodology virtually 

 precludes this. Theroux and Wigley reported crustaceans as being 

 the third most dominant group of animals but these were almost 

 exclusively amphipods which can not be resolved in the 

 submersibles photographs. As a consequence of the sampling 

 methods, it is truly impossible to quantitatively compare the two 

 databases. What is needed is simultaneous sampling using the 

 submersible to characterize the macro-epibenthos and general 

 habitat and grabs to quantify the infauna. 



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