Invasions of ants (Hymenoptera: Formicidae) in light of global climate change

Climate change and biological invasions are among the greatest threats to biodiversity, and their impacts might increase by the end of this century. Among invasive species, ants are a prominent group due to their negative impacts on native species, ecosystem processes, human and animal health, agro-ecosystems, and the economy. Ants are expected to be particularly sensitive to climate change. In this review, we examine the mechanisms by which climate change will affect future ant invasions and whether their interaction could lead to a synergistic effect. We describe three major modelling approaches used to forecast the future of invasions under climate change: species distribution models, mechanistic models, and coupled models, which couple range predictions with dispersal or population dynamics. We then examine predictions for invasive ant species globally, regionally, and within the world's biodiversity hotspots. These predictions are heterogeneous, varying in the magnitude and the direction of the impacts across species and across spatial and temporal scales. Overall, it is unlikely that climate change will systematically increase ant invasions. However, several invasive ants will benefit from more and higher climatic suitability and will therefore have the potential for further spread. Globally, spatial range predictions of future ant invasions will allow comparing and prioritizing the management of certain species and areas. Future development of invasion forecasts under climate change should particularly (a) focus on methodological improvements of the existing methods to qualitatively improve range predictions by incorporating the biotic interactions and microclimatic conditions experienced by ants, (b) tease apart the impacts of climate change on different stages of the invasion process, and (c) account for the combined impacts of changes in habitat disturbance and climate change on invasions