Geo-biology of Mediterranean Deep-Water Coral Ecosystems

Cold (or deep) water corals (CWC) are a spectacular and widespread component of the ocean biota. Highly structured CWC ecosystems serve as biodiversity hotspots suggesting the need for the proper management of these unique habitats. Among the most relevant actors in promoting the growth of conspicuous structures (deep water reefs and mounds) are branching stony corals like Lophelia pertusa and Madrepora oculata. These widespread frame-builders occur also in the Mediterranean basin and are the backbone of Recent CWC provinces identified thus far in the Ionian Sea (Santa Maria di Leuca), South Adriatic Sea, Strait of Sicily, Catalan-Provenc¸al canyons and Alboran Sea. CWC distribution seem strongly influenced by oceanographic factors coupled with proper substrata, such as steep (canyon heads, seamount walls etc.) or rugged (slumped blocks) topographies. Dead pre-Modern coral assemblages are present in the entire Mediterranean Sea. These submerged fossil assemblages have been mostly U/Th and 14C dated at the latest Pleistocene documenting propitious basin-wide conditions for their successful growth during glacial periods.