PS 11-127 - A Review of Theory: Comparing Invasion Ecology and Climate Change Induced Range Shifting

Abstract: Human actions have led to large scale shifts in the distributions of species. The introduction of non-native species to new regions and the shift of species into new ranges to track a changing climate have both contributed. While the context of these species redistributions is not the same, some have advocated applying an invasion framework to the study of range shifting. This idea has been met with strong criticism due in part to the negative connotations around invasive species and conservation fears of applying those to native species that are shifting in range. In this review, I compare the relevance to each research area of the theoretical literature surrounding the success of a species in a new location and the impacts of that species on the previously existing ecosystem. Through an extensive survey of the literature, eight theories were selected based on their perceived relevance to both range shifting and invasion, as well as their general acceptance by the ecological community. Studies addressing these theories were classified by evidence type, study taxa, range shifting or invasion context, and whether the theory was supported. The results demonstrate the usefulness of theories for comparison between different contexts and highlight key differences between range shifting and invasion in factors such as local adaptation and spatial scale. These findings do not support a blanket application of an invasion framework to climate change induced range shifts. However, the two areas of study do have significant overlap and could benefit from each other. Specifically, many of the theories have been empirically tested in invasion systems but not range shifting. Conducting similar experiments to allow for direct comparison could provide insight into both areas of research.