Marine Alien Macrophyte in Sicilian Marine Protected Areas: an updated overview

Non-indigenous species (NIS), widely recognized as one of the main drivers of global change, may in time become invasive, determining significant environmental impacts. Sicilian Islands and all the Marine Protected Areas (MPAs) they host, are vulnerable to biological invasions, due to their strategic position at the crossroads between the South-Western and Eastern Mediterranean Sea, by virtue of the intense maritime traffic. The impact of NIS on marine habitats within MPAs can be significant even highly detrimental. Therefore, monitoring NIS distribution is crucial in these areas for planning effective conservation strategies. This updated overview on NIS within Sicilian MPAs, is based on the analyses of the most up-to-date available literature and personal observations. In Sicilian MPAs 26 NIS are currently reported against 27 registered for the Italian MPAs. Egadi and Ciclopi MPAs registered the highest number of NIS, 13 and 11 respectively. Among NIS, Caulerpa cylindracea was the most frequently recorded species. Our results evidence that protection does not hinder the introduction and spreading of NIS within MPAs. To manage this phenomenon within MPAs, surveillance actions and regular monitoring activities are mandatory in the Management planning. This work represents an important base to create a regularly updated list of NIS within the Sicilian MPAs.