The collective effects of potential drivers on the incidence of non-indigenous species in the Mediterranean: A long-term investigation

Non-indigenous species (NIS) pose a significant threat to society and the ecosystem in the Mediterranean Sea as well as global ecosystems. These species are introduced into marine environments through a combination of various vectors that are likely interconnected. Therefore, this study collectively investigates shipping activities, environmental dynamics, and socioeconomic factors as causative drivers of NIS incidence in the Mediterranean Sea. For this purpose, data sets covering the period between 1993 and 2023 were retrieved from various online databases. The model overall largely explained the incidence rate of NIS (79.3 %) in the Mediterranean Sea. The relative contribution of the selected variables varied between 17.1 % and 7.6 %, population and bulk carrier ships, respectively. Consequently, while some of the examined variables were more important than others, this study clearly indicated that all these causative drivers need to be collectively considered for efficient management strategies of NIS.