The fauna associated with the bank-forming deepwater coralLophelia pertusa(Scleractinaria) on the Faroe shelf

Abstract Twenty five blocks of Lophelia pertusa weighing a total of 18.5 kg were studied. Associated with this substrate were 4626 individuals belonging to 256 species. An additional 42 species were identified from loose coral rubble. Of the 298 species found, 97 are recorded for the first time from the area around the Faroes. Most individuals were found in dead coral blocks from the inner parts of the bank or colony, but a few species were found close to the terminal branches of live coral blocks. The associated fauna of this branching deep-water coral was as rich and diverse as that of hermatypic branching species of coral. Some physical features of the coral as a substrate were measured. Large blocks of live coral harbour a more diverse fauna than do smaller ones. In contrast, on dead coral blocks the number of species and individuals had no simple correlation to block size, indicating the importance of other factors such as random colonization and length of time the substrate has been inhabited. Of the 20 most abundant species only four showed a correlation between the number of individuals and coral weight. Ecological aspects of the associated fauna are discussed and the results are compared with studies from associations on hermatypic corals. Comparing with studies of Lophelia banks from Norway and the Bay of Biscay we find very few overlaps in the associated species. A highly diverse and rich but facultative fauna is associated with the Lophelia banks.