FISHERY BULLETIN: VOL. 84, NO. 3 



the depth and temperature ranges were 137 to 183 

 m, and 13.0° to 10.7°C. Mean number of species was 

 significantly higher in photographs with Cerian- 

 tharia (Mann-Whitney test, P < 0.01): Three groups 

 of epifauna (hydroids, sponges, and small white 

 anemones; Fig. 3D) were attached to Ceriantharia 

 tubes only and not found on the surrounding sub- 

 strate. Also, blackbelly rosefish, Helicolenus dacty- 

 lopterus (De La Roche) (Fig. 3B), and redfish, 

 Sebastes sp. (Fig. 3D), abundances were higher in 

 the Cerianthid C patch (0.40/frame and 0.18/frame, 

 respectively) than in the adjacent area (0.03/frame 

 and 0.00/frame); about half of the fish were nestled 

 at tube bases. 



At other dive locations, motile megafaunal species 

 often seen nestled near tubes included portunid 

 crabs (Bathynectes sp.) (Fig. 3C); jonah crabs, Cancer 

 sp.; pandalid shrimps, Pandalus sp.; American 

 lobsters, Homarus americanus Milne-Edwards; 

 hakes, Urophycis spp.; and greeneyes Chloropthal- 

 mus agassizii Bonaparte. 



Two Cerianthid B tubes (50 m apart) and adjacent 

 sediments were collected with the grab sampler of 

 the submersible Johnson-Sea-Link, in the head of 

 Oceanographer Canyon at a depth of 293 m. The 

 tubes were separated from the adjacent sediments 

 immediately after the submersible surfaced. The 

 volume of each tube was less than the volume of ad- 

 jacent sediments (80% fine sand, <0.5 mm; 10% 

 coarse sand; 10% silt) (Appendix Table 3). After 

 preservation and staining, the macrofauna (>0.5 

 mm) were identified for each sample (Appendix 

 Table 3): Polychaetes were dominant and the three 

 most abundant polychaete species inhabiting the 

 Ceriantharia tubes were absent or scarce in the ad- 

 jacent sediments; Polycirrus eximius (Leily) (a 

 tentacle feeder which sweeps the water and sub- 

 stratum for food), Marphysa sp. (a jawed omnivore), 

 and a filter-feeder, Potamilla neglecta (Sars) 

 (Fauchald 1977; Fauchald and Jumars 1979). 



DISCUSSION 



Collection Gear 



Gear differences largely account for the differ- 

 ences in Ceriantharia size and density estimates 

 from grab samples versus photographs. Due to 

 limitations in resolution, photographs provide valid 

 data only on larger epifauna (Emery et al. 1965; 

 Barham et al. 1967; Wigley and Emery 1967). How- 

 ever, since the estimated depth of penetration of a 

 0.1 m 2 Smith-Mclntyre grab sampler, the gear used 

 most frequently in this study, is only 3 to 5 cm in 



unconsolidated substrates (Smith and Mclntyre 

 1954), and large ceriantharian tubes often extend 

 much deeper than 5 cm below the seafloor (Sebens 

 fn. 5), making them difficult to dislodge, if the 

 primary objective is to sample large individuals and 

 document the associations between tubes and other 

 fauna, then photographs and direct observations are 

 more useful than grab samples. 



Species Identification 



Ceriantheopsis americanus and Cerianthus 

 borealis, identified from grab samples, occurred 

 within the geographic and bathymetric ranges noted 

 previously for these species (Table 1). Unfortunately, 

 many Ceriantharia samples were discarded, and 

 none of the available samples from depths greater 

 than 500 m contained anemones for taxonomic 

 identification. 



The morphological features used to distinguish 

 between the four species seen from submersibles 

 (Table 3) may not individually be reliable; tentacle 

 coloration may vary noticeably within a species (Arai 

 1971; Uchida 1979). However, taken together, we 

 feel the features were consistent enough to indicate 

 we saw four species of adult Ceriantharia: C. 

 borealis (probably Cerianthid B), two unidentified 

 species (Cerianthids C and D) from depths shallower 

 than about 500 m, and another unidentified species 

 (Cerianthid A) living deeper down the continental 

 slope. 



The conclusion that Cerianthid B is C. borealis is 

 based on the similarities between our descriptions 

 of Cerianthid B morphology and distribution (Table 

 3), and information from other studies on C. borealis 

 (Table 1; Gosner 1979). The only other previously 

 identified inhabitant of the study area, C. ameri- 

 canus, was probably not encountered on our sub- 

 mersible dives; the deepest record found for C. 

 americanus was about 70 m (Pearce et al. 1981), 

 whereas our shallowest submersible dive was to a 

 depth of 80 m. 



Sebens (in press) described two unidentified Ceri- 

 antharia species which occur at depths >1,000 m in 

 the Northwest Atlantic: Unidentified Species II 

 (seen at depths >1,500 m) resembles Cerianthid A 

 (Table 3, Fig. 3A), Cerianthid A in Valentine et al. 

 (1980), and a photograph of unidentified Cerian- 

 tharia taken by Grassle et al. (1975) at depths of 

 1,550 to 1,830 m just south of New England. The 

 distinction Sebens (in press) makes between Uniden- 

 tified Species I (seen at depths of >1,000 m) and 

 Unidentified Species II (Cerianthid A) is that Species 

 II is smaller (Table 1). Grassle et al. (1975) and 



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