Three phases of investigation in the protected marine areas of the Gulf of Asinara and Capo Carbonara led to the recovery of about 2 tons of waste extracted from the seabed. A booty consisting of trawls, lost or abandoned fishing gear, fishing lines, trammel nets and pots.
An activity that engaged researchers from Ispra for a year and a half, the body that leads the Mo.Ri.Net project "Monitoring, census, collection and start of recycling of ghost nets", the result of a partnership also made up of PolieCo, University of the studios of Siena, Amp Isola dell'Asinara and Amp Capo Carbonara. The objective was to remove marine litter, in particular lost or entangled nets or parts of them, previously geolocated, in two pilot areas: the protected marine area of the Asinara Park, the Gulf of Asinara and the protected marine area of Capo Bacon and egg.
The results will be illustrated during a meeting in Porto Torres at the Park headquarters. During the first phase of the project, the two areas subject to protection were characterized in terms of biodiversity, with the description of the populations present and the identification of habitats, protected species, areas of value and of conservation importance. At the same time, through the use of Multibeam and ROV tools, the number, type and density of marine litter were determined for an initial assessment of their impact on the communities present. In addition, sampling of microplastics and the taking of biopsies on cetaceans were carried out.
An average of 97 objects per square kilometer were found in the Gulf of Asinara, with a maximum of 732 objects, but in some coves (4 out of 37) no waste was found. The second, and most important phase, allowed for the removal of marine litter. Overall, about 2 tons were collected. In addition to the help of the Cagliari underwater carabinieri nucleus, the contribution of the fishermen who collaborated in the project was invaluable, providing logistical support and collecting on board the fishing boats the waste caught in the nets during their fishing activity.
The lost nets, freed from the bottom by the divers, were then brought to the surface by lifting balloons and set sail by the fishing vessels that offered their support. In the third phase, the recovered waste, given the impossibility of being recycled, took the path of disposal. The Ispra researchers, who constantly monitor the seabed with the help of the ROV, have observed how waste and lost fishing gear interact negatively with the marine environment. The damages are mainly attributable to the phenomenon of entanglement, i.e. the covering, abrasion and/or complete coverage of the organisms.
