eDNA Metabarcoding Analysis as Tool to Assess the Presence of Non-Indigenous Species (NIS): A Case Study in the Bilge Water

One of the most important causes of biodiversity loss are non-indigenous species (NIS), in particular invasive ones. The dispersion of NIS mainly depends on anthropogenic activities such as maritime traffic, which account for almost half of the total NIS introduction in the European seas, as reported by the European Environmental Agency. For this reason, NIS management measures are mainly focused on commercial ports (i.e., ballast water management and Marine Strategy Framework Directive monitoring), underestimating the role of marinas and tourist harbors; these host small vessels (