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Fishery Bulletin 93(2), 1995 



2627, 2629, 2630), but was more common at the 

 middle slope site (dive 2623). 



Anemones, echinoderms, gastropods, and inverte- 

 brate tracks were common. Epifaunal forms tended 

 to occur in patches. Coefficients of dispersion (CD, 

 Sokal and Rohlf, 1981) were calculated for small 

 anemones, large anemones, crinoids, and gastropods 

 (data in Table 2). Coefficients of dispersion much 

 greater than 1 (indicating clumped distribution pat- 

 terns) were found for small anemones in all Cape 

 Hatteras dives where they were observed. Small anemo- 

 nes were very abundant in dive 2627. For 15 minutes, 

 the submersible traversed a dense aggregation where 

 numbers ranged from 30 to 80 individuals per inter- 

 val. Small anemones were also common (though not as 

 densely distributed) in dive 2629. Large anemones were 

 seen regularly and were relatively dense in dive 2629 

 (up to 12 in an interval ). Large anemones had a clumped 

 distribution in this dive, indicated by a high CD value. 

 Coefficients of dispersion were very high for crinoids. 

 A dense patch of crinoids appeared in dive 2629, with 4 

 to 62 individuals per interval for 6 consecutive inter- 

 vals. Another area of dense crinoids appeared in dive 

 2623, with 7-70 individuals per interval in 10 consecu- 

 tive intervals. In dive 2630, an extremely dense patch 

 of ophiuroids appeared over 4 consecutive intervals 

 (ophiuroids were not included in the statistical analy- 

 sis as they were seen in so few intervals). 



Cape Lookout — Holes and mounds were very dense; 

 holes were, in fact, too dense to count during some 

 portions of dives 2619 and 2621. As at Cape Hatteras, 



intervals with high numbers of holes also had large 

 numbers of mounds. Tubes were rarely observed and 

 were not seen in dive 2620. Grass detritus was com- 

 monly seen but was not as frequent as at Cape 

 Hatteras. Conversely, sargassum detritus was quite 

 frequent, occurring in 39-41% of Cape Lookout in- 

 tervals. Epifaunal species were not abundant and 

 were not patchily distributed. Small anemones were 

 not common (fewer than one per interval) and were 

 less abundant than large anemones. No crinoids were 

 seen in the Cape Lookout dives. 



Demersal nekton species 



Many nektonic species were observed on the tapes, but 

 only a few appeared in abundance. These were the spe- 

 cies included in analysis of habitat preferences. As no 

 voucher specimens were obtained, identifications were 

 assigned on the basis of species known to be common 

 in the area, after consultations with taxonomic experts 

 (listed in the Acknowledgments section). Table 3 lists 

 the species included in analyses of habitat choice and 

 their mean numbers in particular dives. 



The eel (Synaphobranchus sp.; Smith 5 ), though 

 rare at Cape Hatteras, was the most abundant form 

 at Cape Lookout. This genus forms an important part 

 of the middle-slope fauna (Markle and Musick, 1974; 

 Haedrich et al., 1980; Sulak 6 ). Eels were always ob- 



5 Smith, D. G. National Museum of Natural History, Washing- 

 ton, DC. Personal commun., 1992. 



6 Sulak, K. Atlantic Reference Centre, Huntsman Marine Sci- 

 ence Centre, New Brunswick, Canada. Personal commun., 1990. 



