Identification and distribution of non-indigenous species in the Mediterranean Sea: the Italian challenge.
Non-indigenous species (NIS) represent one of the main threats for world biodiversity, both in the terrestrial and in the marine environment, to such an extent that they are an important subject of several international conventions and directives aiming at safeguarding the environment. Since 2002, the Institute of Environmental Protection and Research (ISPRA), in cooperation with the Italian Ministry of the Environment, conceived a research project to comply with Article 8h of the Convention on Biological Diversity - aiming at preventing the introduction of, controlling or eradicating those alien species which threaten ecosystems, habitats or species - and with Article 13 of the Specially Protected Areas and Biological Diversity Protocol of the Barcelona Convention - focusing on regulating intentional or accidental introduction of non-indigenous or genetically modified species in nature. This project had the purpose of monitoring marine NIS in Italian seas and, more generally, in the whole Mediterranean Sea which is estimated to be the most invaded sea in the world, counting to date 955 NIS (Zenetos et al. 2010).