Understanding the likely future impacts of biological invasions is crucial yet highly challenging given the multiple relevant environmental, socio-economic and societal contexts and drivers. In the absence of quantitative models, methods based on expert knowledge are the best option for assessing future invasion trajectories.

This study presents an expert assessment of the drivers of potential alien species impacts under contrasting scenarios and socioecological contexts through the mid-21st century.

Based on responses from 36 experts in biological invasions, the authors show that moderate (20%-30%) increases in invasions, compared to the current conditions, are expected to cause major impacts on biodiversity in most socioecological contexts. Three main drivers of biological invasions (transport, climate change and socio-economic change) were predicted to significantly affect future impacts of alien species on biodiversity.

The study concludes that some best-case scenarios can substantially reduce potential future impacts of biological invasions. However, the authors highlight that rapid and comprehensive actions are necessary to use this potential and achieve the goals of the Post-2020 Framework of the Convention on Biological Diversity.


Essl et al. (2020) Drivers for future alien species impacts: An expert-based assessment. Global Change Biology 26:4880-4893.