Fouling assemblages associated with off-coast aquaculture facilities: an overall assessment of the Mediterranean Sea

Aquaculture facilities provide a suitable habitat for a wide group of marine species that are able to colonise and settle on artificial structures. This study aims to determine the composition of fouling communities in off-coast facilities, with special emphasis on motile epifauna and amphipods as a main group. Seventeen aquaculture sites were sampled along the Mediterranean coast, collecting samples by scraping fouling organisms directly from the ropes. Additionally, thirty publications were reviewed, in order to assess the similarity of aquaculture fouling with other fouling communities. Our results reflect that amphipods accounted for more than 80% of the epifauna associated with farms fouling communities. This characteristic epifauna was defined by seven amphipod species well-adapted to colonise and survive in these off-coast habitats. Most species common in farms have also been commonly found in harbours, marinas, and/or offshore on turtles, buoys or platforms etc., showing a great resistance to polluted areas but also to dispersal via rafting on floating objects. In this study, two exotic species were identified: Caprella scaura and Stenothoe georgiana, the latter being the first report from the Mediterranean Sea. The presence of Jassa slatteryi was also confirmed, underestimated until now in the Mediterranean.