Predicting global climatic suitability for the four most invasive anuran species using ecological niche factor analysis

Invasive species have a massive impact on their environment and predicting geographical zones at risk of invasion is paramount to the control of further invasions. Invasive anurans are particularly detrimental to native amphibian species, other vertebrates, and even aquaculture through competition, predation, disease transmission, toxicity, or a combination of these. Four species have been designated as the worst anuran invaders worldwide: Duttaphrynus melanostictus, Rhinella marina, Lithobates catesbeianus and Xenopus laevis. In this study, we modelled global habitat suitability for all four species using ecological niche factor analysis (ENFA) to predict the most susceptible areas to invasion. Models showed suitable climatic conditions for all four species expanded beyond their current native and invasive ranges. Tropical, subtropical, and island biomes around the world were among the areas with the highest ENFA suitability for all four species. Further, marginality statistics indicate niche expansion in D. melanostictus, and generalism in the three other species. As only climatic variables were used in the modelling, these results show the ultimate distributions if all landscape conditions are met without significant barriers to invasion.