Distribution and behaviour of deep-sea benthopelagic fauna observed using towed cameras in the Santa Maria di Leuca cold-water coral province

Using a towed camera system, a total of 422 individuals belonging to 62 taxa (including 33 identified species) were counted in the Santa Maria di Leuca (SML) coral province (Mediterranean Sea). Our findings update the knowledge of the biodiversity of this area and of the depth records of several species. The presence of coral mounds mostly in the north-eastern sector of the SML coral province seems to influence the large scale distribution of the deep-sea benthopelagic fauna, playing the role of attraction-refuge with respect to the barren muddy bottoms where fishing occurs in northern areas. Multiple Correspondence Analysis identified 3 main taxa groups: (1) rather strictly linked to the bottom, resting or moving on the seabed, often sheltering and feeding; (2) mostly swimming in the water column and mostly observed on rugged bottoms; and (3) actively swimming or hovering near the seabed. The behavioural patterns largely related to activity and position of the fauna seem to determine their small-scale distribution. The effects of different benthic macrohabitats appear to be less important and the depth within the bathymetric range examined even less so. The behavioural patterns reflect aspects of the species life strategies, revealing common features in phylogenetically and ecologically distant species. The teleost Helicolenus dactylopterus exhibited a clear behavioural pattern of resting on the seabed in different macrohabitats. The golden shrimp Plesionika martia and the fish Pagellus bogaraveo seem to be associated with the presence of corals.