Ecological niche modeling and the importance of human disturbance in predicting the distribution of an invasive ant, Wasmannia auropunctata, under current and future conditions

Invasive species are one of the leading causes of global biodiversity loss and management efforts can reach into the billions of dollars. Predictive modeling can be used to guide management decisions aimed at preventing further spread of invasive species. Studies that utilize modeling techniques typically focus on climatic variables. However, anthropogenic disturbance is another important factor that impacts biological invasions. The little fire ant, Wasmannia auropunctata, (LFA) is an invasive ant present in Florida that has had negative impacts on ecosystems and economies around the globe. To date, the role of disturbance in describing its ecological niche and its potential to spread further into the United States was unknown. Here I utilized ecological niche modeling (ENM) techniques to predict the potential distribution of LFA in the southeastern US by generating Maxent and ensemble models using climatic and disturbance variables under current and future conditions and two climate change scenarios. I asked the following questions: (1) is human disturbance important in describing LFA’s ecological niche?; (2) what is the current potential distribution of LFA in the southeastern US?; and (3) how will its potential distribution shift by the years 2050 and 2070? I found that human disturbance is important in describing this species ecological niche. I also found that LFA’s potential distribution currently extends beyond its observed range in Florida, and that suitable areas will expand under future conditions. These results will be important for guiding management decisions that aim to prevent further spread of LFA in the southeastern US.