Macrofaunal structure and habitat utilization within deep coral bank communities on the southeastern United States slope

No abstracts are to be cited without prior reference to the author.

Deep coral banks, composed mostly of Lophelia pertusa, occur in scattered patches off the southeastern US (350-700 m). Fish and invertebrate communities of these banks are poorly known. Also, the affinity of organisms for reef habitat in the deep sea is not well understood. From 2000-2004 we surveyed the macrofauna of deep coral banks off the Carolinas using a research submersible and bottom trawls. We documented community structure (composition, abundance, sizes, habitat utilization) of macrofauna on and near the coral habitat, and investigated to what extent the fauna is obligate to the reef. In particular how are organisms distributed within the reef structure (prime high reef, secondary low colonies, coral rubble zones)? Continental slope Lophelia coral banks off the southeastern US support a distinctive fish assemblage compared to non-coral habitats of similar depths. We have identified over 41 fish species and approximately 20 invertebrate species on coral banks. Numerically dominant fish species observed on this habitat include Beryx decadactylus, Helicolenus dactylopterus, Laemonema melanurum, Hoplostethus occidentalis, Conger oceanicus, and L. barbatulum. Numerically dominate invertebrates include two crustaceans (Eumunida picta, Rochinia crassa) and four echinoderms (Ophiacantha bidentata, Echinus gracilis, E. tylodes, Novodinia antillensis). Several fishes (Squalus asper, L. melanurum, H. occidentalis, S. meadi, and B. decadactylus) may be restricted to the coral habitat and should be considered primary reef fishes. The invertebrates, however, are common locally and may use the habitat more opportunistically. Further investigation will add species to this deep reef assemblage and help refine our hypothesis of primary reef associates versus opportunistic reef utilization.