Fishing impact on Italian deep coral gardens and management of these vulnerable marine ecosystems

Coral gardens have been internationally recognized as unique habitats characterized by numerous structuring species, generating complex and fragile ecosystems, which act as important oases of biodiversity in the deep realm. Deep corals are generally believed to constitute poorly resilient assemblages presenting a low recovery potential from the impact of destructive deep fishing activities. For these reasons, the international scientific community has recently proposed the inclusion of some of these species in many protection lists, recognizing their ecological value and their vulnerability to human activities. A wide ROV video archive was used to characterize the fishing impact on numerous deep rocky shoals along the entire Tyrrhenian and Ligurian Seas (Italy). Lost fishing gears represent the great majority of the marine litter on the bottom, reported in the totality of the explored sites. Some regional differences were highlighted, with Liguria and Campania among the most impacted areas. Various features, such as the explored depth range, the accessibility of the shoals and the local fishing traditions play a synergistic role in defining the observed pattern. Additional indicators of impact have been identified in order to characterize the health status of the coral aggregations in heavily impacted fishing grounds. No active ecosystem-based fishery management of the deep Italian rocky shoals hosting these coral gardens has still been defined, if we exclude some local initiatives. A network of deep marine protected areas, that might apply experimental fishing restrictions, is here proposed for the Italian Seas.