Some species that are introduced into new areas experience higher demographic success in their invaded compared to their native ranges. This phenomenon referred to as "invasion success," is one mechanism by which species become invasive and have impacts. Altered ecological interactions between species native and invaded ranges drive invasion success. We conduct research on the role of altered ecological interactions in driving invasion success, along with the consequences of invasion success on native ecological communities. Phytophagous insects are widespread, and often high-impact invaders. Population dynamics of phytophagous insects are governed by both top-down (enemy) and bottom-up (host plant suitability) processes, and ultimately interactions between host plants and enemies (tri-trophic interactions), and abiotic interactions. We are exploring the role of both top-down and bottom-up processes in driving the success of an invasive oak-gall former, Neuroterus saltatorius, that was introduced from Washington state to Vancouver Island, BC, Canada. This system is an ideal system to conduct rigorous tests of invasion success because this short distance introduction makes native vs. invaded range comparisons of the strengths of ecological interactions feasible and tractable. We are examining 1) how enemy parasitoid communities assemble on to novel host populations in invaded locations, 2) the role of host plant suitability and tri-trophic interactions in driving invasion success, 3) and the impacts of this species on native ecosystems.
We collaborate with Tom Powell (Binghamton University) and Jessica Hellmann (University of Minnesota) on this research.
We conduct this work in western oak ecosystems, including the threatened Garry oak ecosystem on Vancouver Island, BC.
2013: Prior KM, Hellmann JJ. Does enemy loss cause release? A biogeographical comparison of parasitoid effects on an introduced insect. Ecology 94:1015-1024.
2012: Hellmann JJ, Prior KM, Pelini SL. The influence of species interactions on geographic range change under climate change. Annals of the New York Academy of Sciences 1249:18-28.
2010: Prior KM, Hellmann, JJ. Impact of an invasive oak gall wasp on a native butterfly: a test of plant-mediated competition. Ecology 91:3284-3293.