Dispersal asymmetries between species in multi-trophic foodwebs: implications for species invasions

Background/Question/Methods Theory shows that species in communities with competition and predation exhibit dispersal asymmetries: dispersal of species that are inferior competitors for a common resource but less susceptible to a common natural enemy have a disproportionately large effect on coexistence and species' distributions compared to species that are superior competitors but are more susceptible to a common natural enemy. Such asymmetries can play an important role in species invasions. For instance, an exotic species that is an inferior resource competitor compared to native species may nevertheless successfully invade and spread if it is less susceptible to the natural enemies that attack the native species. Results/Conclusions I investigate the consequences of dispersal asymmetries for species invasions in both spatially patchy and spatially continuous environments. I derive comparative predictions for the conditions under which dispersal asymmetries between native and invasive species facilitate vs. impede invasion success.