Climatic Niche Breadth Predicts Invasion Success at the Transport Stage in Ants

Aim Identifying traits that predispose species to successfully invade environments is key to predicting future invaders. A large climatic niche breadth in the native range has been hypothesized to increase invasion success elsewhere. Previous investigations of this hypothesis have mostly focused on a single stage of the invasion process, often establishment or spread, potentially obscuring the effect of niche breadth across stages. Additionally, most studies have focused on vertebrates and higher plants, largely overlooking invasions of terrestrial invertebrates. Over 500 ant species have been transported beyond their native ranges with varying degrees of subsequent invasion success. Location Global. Methods We quantified the native climatic niche breadth of 1420 ant species. Using logistic regression models, we then modelled species' success in transport, establishment and invasiveness according to native niche breadth, while accounting for native range size and shared ancestry among genera. Results By isolating transport and establishment, we showed that native niche breadth and range size promoted likelihood of transport, but not establishment. This contrasts with previous findings in plants and vertebrates where niche breadth was consistently associated with establishment success. Finally, native niche breadth showed only weak support as a predictor of impact‐based invasiveness and did not predict spread‐based invasiveness. Main Conclusions Our study highlights the importance of investigating transport success and explicitly modelling invasion stages.