Invasion biology has faced a number of challenges concerning the impacts of invasive alien species. One such challenge is the development of predictive methodologies that can reliably forecast the ecological impacts of existing, emerging and potential invasive species. These challenges need to be addressed to advance both the fundamental science of invasion ecology and provide practical methodologies that can mitigate invasions.
Consequently, the comparison of the classical ‘functional response’ (relationship between resource use and availability) between invasive and trophically analogous native species may allow prediction of invader ecological impact. Indeed it has now been shown that a range of damaging invasive species have consistently higher functional responses than comparator native species. Importantly is has been shown that such heightened responses correlate to a high degree with known field impacts. Ecological impact of new and emerging invaders may therefore be predicted by the magnitude of difference in such functional responses.
In this seminar, a review of this work to date will be presented, demonstrating how comparisons between invasive and native species allow for testing of the likely population-level outcomes of invasion events for affected species. The methodology, already supported by a number of studies, is highly transferable and discussion will be made on its applicability across a range of systems. It thereby provides a tool that will aid in filling in gaps that exist in theory and application for the prediction of impact by invasive species.