Non-indigenous macrophytes in Adriatic ports and transitional waters: Trends, taxonomy, introduction vectors, pathways and management.

The Adriatic Sea is considered as a hotspot of marine biodiversity but, due to intense human activities (e.g. maritime transport, mariculture), it is also a recipient area of non-indigenous species (NIS). This study analyzed the scientific literature on non-indigenous macrophytes (NIM) recorded in ports, marinas and transitional waters (TWs) of the Adriatic Sea, in the period 1987-2018. The results show that 51 out of 118 Mediterranean NIM are found in Adriatic ports and TWs. The Venice Lagoon is the main Adriatic recipient area of NIM. Mariculture is the main vector of introduction, whereas the principal pathways of NIM dispersal are shipping and shellfish transfer. The largest group of NIM is of temperate northern Pacific origin. This study corroborated the fact that ports and TWs act as dispersal hubs and invasion hotspots. The importance of early detection of NIM at such sites should be considered in any environmental management strategy.