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Detailed knowledge about the distribution of species in need of protection is required for the management of Marine Protected Areas, a major tool to reduce marine biodiversity loss. Such knowledge is deficient for most marine invertebrates. Axinella polypoides is a marine sponge included on the list of protected species by the Barcelona Convention (1976) and the Bern Convention (1987). This large and erect species has an important ecological role in habitat forming and benthic–pelagic coupling. Bathymetrical, geographical and ecological data over the last 60 years were collated from publications and reports, together with new surveys to assess the distribution and protection status in Liguria of A. polypoides. It identified a more widespread distribution than previously thought, which points at a general need for dedicated investigations on the occurrence of species that require protection. Bathymetrical distribution was trimodal, with peaks corresponding to different geomorphological settings: coastal cliff bases (around 38 m depth), inner shelf shoals (52 m) and rocks amidst coarse sediment on the outer shelf (79 m). Density was significantly greater at the shallowest depths. The species was mostly found in the coralligenous biocoenosis, in association with other characteristic species or forming a monospecific facies. On (sub)vertical cliffs, A. polypoides often exhibited an unusual cane shape, rather than the typical bushy morphology, thus causing confusion with the congeneric A. cannabina, a more southern species. Records of the latter in the Ligurian Sea therefore need confirmation. Only a minority (22.6%) of A. polypoides records were in Marine Protected Areas, the remainder being located in areas with no current environmental protection plans in place. While the occurrence of this species in MPAs remained stable over the decades, the only quantitative historical data available indicated that populations in non‐protected areas were declining owing to anthropogenic impacts (fishing and anchoring).

Recent ROV surveys conducted on the Ragusa bank in the Sicily Channel (Mediterranean Sea) documented illegal and continuous use of the ‘ingegno’ gear for red coral fishing. Three lost gears were recorded showing different levels of epibiosis thus supporting multi-annual exploitation of the bank. The red coral population of the Ragusa bank showed a typical ‘forest-like’ configuration with upright, medium-sized colonies similar to those of other commercially exploited deep Mediterranean banks. The direct negative effect of this trawling gear was evident from numerous rocky boulders completely enveloped by lost nets and occasionally turned over. Red coral fragments as well as fragments of ‘ingegno’ nets were observed in high abundance on the sea floor. This evidence suggests that this gear is highly destructive even on rough sea floors, contrary to the traditional view, which is that it has a more random impact on rough rocky bottoms. The estimated coral uptake of ‘ingegno’ is 45% of the total coral biomass, while the estimated coral loss, in terms of fragments, is 9%, demonstrating the high impact of this gear. The study highlighted the infringement of the red coral fishing ban by trawling gears as well as a lack of effective policing. The strengthening of controls on landings at nearby harbours, and education programmes for the local maritime communities are among the management actions proposed to protect these surviving red coral populations from the ongoing illegal fishing activity.

Association between habitat structuring organisms and other species has great relevance for ecosystem-based conservation measures. Those occurring in temperate areas, particularly in the upper portion of the continental margin, are mostly unknown or not properly understood because of the difficulty to discriminate co-occurrence and real functional linkages among species. Deep water coral assemblages over the Carloforte Shoal (south-west Sardinia; 180–210 m depth) were investigated using ROV surveys. During the surveys, more than 740 egg-capsules of the spotted catshark Scyliorhinus canicula, identified after hatching experiments in captivity, were found attached exclusively to colonies of the long-living black coral Leiopathes glaberrima. Although based on a spot finding, the results show that coral forests are not only hotspots of biodiversity, but can also serve as nursery grounds for S. canicula. The protection of these millennial coral forests is therefore to be considered a priority.