Invasion Dynamics of the Alien Amphibian Xenopus laevis in France: Perspectives for Management

ABSTRACT Background: Invasive alien species (IAS) are recognised as pervasive drivers of global environmental change and pose significant threats to socio-ecosystems worldwide. Although much attention is focused on prevalent IAS, the oversight of species that are still contained and approaching critical invasion thresholds raises concern. In this context, scientific support to implement effective and spatially informed management strategies is critically needed. Aims: Our study focuses on the African clawed frog, Xenopus laevis, a concerning IAS projected to undergo a substantial expansion in Europe. Materials & Methods: Using a comprehensive analysis of three distinct datasets, our study aimed to document newly colonised sites and provide an up-to- date overview of the current distribution and invasion dynamics of X. laevis in France. Results: Our results revealed recent colonisation of new sites within the established range of the species and the continuous progression of the invasion front at a rate of 1.2 km per year. This annual progression currently translates to an expansion of approximately 400 km2 per year in the predicted distribution range of the species. Discussion: Emphasising the urgent need for proactive management, we recommend measures encompassing prevention, early detection and rapid responses to invasion, delineated across three strategic zoning levels. Conclusion: Immediate and coordinated efforts are imperative to anticipate and mitigate the considerable socio-environmental impacts associated with this species in the future.