A mesophotic black coral forest in the Adriatic Sea

Abstract

A forest of the black coral Antipathella subpinnata was found from 52 to 80 m depth in three different sites at Tremiti Islands Marine Protected Area (MPA; Mediterranean Sea), with two of them hosting a monospecific forest on horizontal and vertical substrates. Colonies of A. subpinnata showed a mean density between 0.22 ± 0.03 and 2.40 ± 0.26 colonies m −2 (maximum local values of 2.4-7.2 colonies m −2). The link between the local distribution of A. subpinnata and the main oceanographic features confirmed the fundamental role of the currents in shaping the distribution of the species in presence of hard substrata. This black coral forest represents the only one known thus far in the Adriatic Sea, but it could be linked with other unseen forests all over the Mediterranean Sea. The associated megafauna highlights the importance of these forests as habitat for species of both conservation and commercial importance but, at the same time, makes such habitat a target for fishing practices, as many lost fishing gears were found within the coral forest. The enlargement of the MPA borders and the enforcement of controls in the area of the A. subpinnata forest is urgently needed for the proper conservation of this protected species.

Impacts of Marine Litter on Mediterranean Reef Systems: From Shallow to Deep Waters

“…highlighting as marine litter represents one of the major pollution problems harming benthic organisms and habitats (Gilman, 2015). These methods do not cause any impact to the marine environment and are thus applicable in protected and sensitive areas such as marine protected areas (MPAs) and coral reefs (e.g., Betti et al, 2019Betti et al, , 2020Chimienti et al, 2020). From videos and frame/photo, it is possible to obtain high-resolution quantitative data (depending on optical device), precise geolocalization, and provides in situ information at various depths.…”

“…They recovered with an Agassiz trawl some fragments of a Desmophyllum pertusum colony growing on a nylon net cords at 752-864 m depth in the Blanes Canyon (Western Mediterranean Sea). Chimienti et al (2020) observed a steel cable directly within a group of Antipathella subpinnata colonies in the Tremiti Islands MPA. Angiolillo and Canese (2018) observed fishing lines fully incorporated in the yellow scleractinian Dendrophyllia cornigera on the Mantice Shoal in the Ligurian Sea.…”

“…The accumulation of fishing debris represents one of the major causes of habitat degradation of Mediterranean reefs. Thus, destructive practices (e.g., fishing and anchoring) that can threaten arborescent corals should be banned in the proximity of the coral forests (Chimienti et al, 2020).…”

“…Bioconstructor frameworks can provide a complex network of ecological niches for a large variety of organisms, including endangered and protected species, as well as species of high commercial value (Chimienti et al, 2020), functioning as habitat for shelter and feeding, spawning and nursery areas, substrata for both larval settlement and juvenile growth (e.g., Tursi et al, 2004;D'Onghia et al, 2010D'Onghia et al, , 2015Rosso et al, 2010). Since bioconstructions increase spatial complexity and settlement opportunities at every level, they are known worldwide to play a pivotal ecological role in enhancing and maintaining high marine biodiversity.…”

Local Conditions Influence the Prokaryotic Communities Associated With the Mesophotic Black Coral Antipathella subpinnata

“…Antipathella subpinnata commonly lives in mixed assemblages with arborescent gorgonian octocorals, such as Paramuricea clavata (Risso, 1826) ( Enrichetti, 2019 ; Chimienti et al, 2020 ) and Eunicella cavolini (Koch, 1887) ( Bo et al, 2009 ; Gori et al, 2017 ), which are commonly found at shallow and mesophotic depths. While it is unknown how these black corals and gorgonians interact, the similar colony structures and polyps sizes ( Weinberg, 1976 ; Bo et al, 2018 ) suggest that they may occupy the same trophic niche.…”