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Commercially harvested since ancient times, the highly valuable red coral Corallium rubrum (Linnaeus, 1758) is an octocoral endemic to the Mediterranean Sea and adjacent Eastern Atlantic Ocean, where it occurs on rocky bottoms over a wide bathymetric range. Current knowledge is restricted to its shallow populations (15-50 m depth), with comparably little attention given to the deeper populations (50-200 m) that are nowadays the main target of exploitation. In this study, red coral distribution and population structure were assessed in three historically exploited areas (Amalfi, Ischia Island and Elba Island) in the Tyrrhenian Sea (Western Mediterranean Sea) between 50 and 130 m depth by means of ROV during a cruise carried out in the summer of 2010. Red coral populations showed a maximum patch frequency of 0.20 ± 0.04 SD patches·m−1 and a density ranging between 28 and 204 colonies·m−2, with a fairly continuous bathymetric distribution. The highest red coral densities in the investigated areas were found on cliffs and boulders mainly exposed to the east, at the greatest depth, and characterized by medium percentage sediment cover. The study populations contained a high percentage (46% on average) of harvestable colonies (>7 mm basal diameter). Moreover, some colonies with fifth-order branches were also observed, highlighting the probable older age of some components of these populations. The Ischia population showed the highest colony occupancy, density and size, suggesting a better conservation status than the populations at the other study locations. These results indicate that deep dwelling red coral populations in non-stressed or less-harvested areas may diverge from the inverse size-density relationship previously observed in red coral populations with increasing depth. [ABSTRACT FROM AUTHOR]

In this study we characterized the deep assemblages dwelling at 200-250 m depth on a large shoal off Capo St. Vito Promontory ( Northwestern coast of Sicily, South Tyrrhenian Sea) by means of ROV-imaging. Two assemblages of suspension feeders, dominated by the gorgonian Callogorgia verticillata and by the black coral Leiopathes glaberrima, together with a tanatocoenosis of the colonial yellow scleractinian coral Dendrophyllia cornigera, were examined. The three main species were significatively distributed into two areas corresponding to different habitat preferences: a more elevated hardground hosting black corals and a gently sloping, silted rocky bottom hosting the other coral species. The study area is subjected to a heavy pressure from the professional fishery, resulting in the mechanical damage of numerous colonies, some of which are then overgrown by various epibionts including a parasitic bioluminescent zoanthid, new for the Mediterranean fauna, and tentatively identified as Isozoanthus primoidus. In the Mediterranean Sea, these deep off-shore rocky banks are widely known among recreational and professional fishermen due to their rich fish fauna. However, there has been still little effort into quantifying and characterizing the extent of the impact and its consequences on the benthic communities, which may represent, as in this case, only a partial picture of their original structure and extent. [ABSTRACT FROM AUTHOR]

The occurrence of the candelabrum coral Ellisella paraplexauroides in Italian waters (Sicily Strait, Mediterranean Sea), was documented during a remotely operated vehicle cruise, carried out by ISPRA in May 2010 on-board the RV ‘Astrea’. Five specimens were photographed and sampled from 80 to 94 m depth on the north-east coasts of Pantelleria Island, confirming the distribution of this species in the central Mediterranean Sea. A description of the living colonies and other taxonomic and ecological characteristics is provided. [ABSTRACT FROM AUTHOR]

The anthropogenic marine debris, especially abandoned, lost or otherwise discarded Fishing Gear (ALDFG), represents a rising concern, because of its potential harmful impact on the marine animal forests. We carried out 13 km of video recordings, by means of a remotely operated vehicle, from 10 to 210 m depth, in an anthropised area of the Tyrrhenian Sea (Mediterranean Sea). This site, for its high ecological importance and biodiversity value, has been identified for the establishment of a new marine protected area (MPA). The aim of this paper was to assess marine litter abundance and its effects on the benthic fauna. The debris density, in the study area, ranged from 0.24 to 8.01 items/100 m 2 , with an average of 3.49 (±0.59) items/100 m 2 . The derelict fishing gear, mainly fishing lines, were the main source of marine debris, contributing 77.9% to the overall litter. The impacts of debris on the benthic fauna were frequently recorded, with 28.5% of the litter entangling corals and impacting habitats of conservation concern. These impacts were exclusively caused by the derelict fishing gear (91.2% by longlines), and the highest percentage (49.1%) of ALDFG causing impacts was observed from 41 to 80 m depth, in the coralligenous biocenosis. The results of the present study will help the fulfilment of "harm" monitoring, as recommended by the Marine Strategy Framework Directive (MSFD) and the UN Environment/MAP Regional Plan on the marine litter management in the Mediterranean Sea. Regarding the actions to reduce the derelict fishing gear, preventive measures are usually preferred instead of the extensive removals based on cost-effectiveness and sustainability. The establishment of a new MPA in the area could be a good solution to reduce ALDFG, resulting in the improvement of the ecological status of this coastal area., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A Mediterranean "roche du large" ecosystem, represented by four rocky shoals, located a few miles apart on a muddy bottom at 70-130 m depth in the gulf of St. Eufemia (Calabria, South Tyrrhenian Sea), was studied by means of Remotely Operated Vehicle (ROV) photo imaging. The shoals host highly diversified coral communities, mainly composed of arborescent colonies of gorgonians (Callogorgia verticillata, Paramuricea clavata, Paramuricea macrospina, Bebryce mollis, Villogorgia bebrycoides, Corallium rubrum, and Leptogorgia sarmentosa), and antipatharians (Antipathella subpinnata, Antipathes dichotoma and Parantipathes larix). The coral colonies reach high densities (up to ca. 17 colonies m(-2)) and large sizes, such as the over 1.5 m wide antipatharian colonies. We hypothesized that the abundance and composition of the coral assemblages differed significantly among the rocky shoals and with respect to the surrounding soft bottoms. Various environmental variables were tested as possible explanatory factors of the observed differences. Moreover, due to their off-coast localization, we report here that these unique ecosystems are potentially subjected to a strong pressure from the local fishing activities, which were tentatively characterized. The recorded coral β-diversity among the shoals supports the hypothesis that these habitats behave like small oases of hard substrata interspersed in a muddy bottom. Because of their intrinsic beauty and rarity and their biological and ecological value, we stress the need of specific actions aimed at the urgent protection of these oases of biodiversity.