Using trait and niche data to assess ecological impacts of alien species

Impacts of alien species can vary spatiotemporally, and coupled with a lack of empirical data impact assessments often exhibit high uncertainties. Experimental approaches can generate reliable results, although these can be time-consuming and resource demanding, especially in highly invaded systems such as cities. Here I provide examples of how observational approaches using niche data can uncover processes limiting alien species establishment, while trait data can identify alien species with the strongest ecological impacts. As niche and trait data become increasingly available, impact assessments can more accurately and rapidly identify impactful alien species that should be prioritized for management.