AIS data, a mine of information on trawling fleet mobility in the Mediterranean Sea

Armelloni, Enrico Nicola; Tassetti, Anna Nora; Ferrà, Carmen; Galdelli, Alessandro; Scanu, Martina; Mancini, Adriano; Fabi, Gianna; Scarcella, Giuseppe;

In the Mediterranean Sea, fishing vessels often operates throughout the geographical subdivisions adopted for statistical data collection (Geographical Sub-Areas; GSAs), causing a potential mismatch between catches site and reporting site. This paper provides a quantitative assessment of the fluxes of fishing activity of bottom trawlers across the Mediterranean Sea, by analyzing the Automatic Identification System (AIS) data broadcasted in 2017. Fishing activity was analyzed from three perspectives: fishing site, port of arrival and registration site of the vessel. For each GSA, a “fidelity score” was calculated to quantify the proportion of fishing time spent in the home GSA; an “intrusion score” was computed to quantify the effort deployed by vessels registered elsewhere. Major vessel fluxes were detected between GSAs, and fleets were classified based on their mobility. Areas showing fleet overlaps were identified and those characterized by the largest overlaps were selected as case studies. The lowest fidelity scores were observed in the central Mediterranean (GSAs 11.2, 15, 16 and 18), while the highest intrusion score was recorded in the southern Mediterranean and around Crete. The vessels responsible of the largest fluxes were those registered in GSAs 16, 18, and 6. The case studies included: GSAs 23, where several fleets exploited narrow slope areas; GSA 13, where multiple fleets overlapped in a relatively wide area; and GSA 17, where two fleets overlapped in a wide platform area. Mobility was distinguished in short-range – involving platform areas of contiguous GSAs – and long-range – involving slope areas of non-contiguous GSAs.

2021 - Journal article

Marine policy 129 (2021). doi:10.1016/j.marpol.2021.104571

Keywords: AIS data, Fishing effort, Fleet mobility, Geographical Sub-Areas, Mediterranean Sea

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The research activities of the Institute are carried out in the context of research, development and innovation projects, both national and international, based on regional funding programs (POR FEAMPA - Regional Operational Program of the European Maritime Affairs Fisheries Fund and Aquaculture and POR FESR - Regional Operational Program of the European Regional Development Fund) or ministerial (PRIN - Projects of relevant national interest, PNRA - National Research Program in Antarctica, PO FEAMPA - National Operational Program European Maritime Affairs Fisheries and Aquaculture Fund) , programs for European Territorial Cooperation (Interreg), direct funding programs of the European Commission (Horizon2020 and Horizon Europe, Life, JPI - Joint Programming Initiatives, ERA-NET Cofund) and thematic collaboration initiatives managed by international organizations such as, for example , the FAO - GFCM (General Fisheries Commission for the Mediterranean). The Institute also develops funded projects in the context of collaborations with private companies in the sectors of the blue economy as well as technology transfer and research results. Research projects, mainly of a collaborative nature, are developed through a wide network of partners that include major Italian and foreign research institutions and universities.

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