Wednesday, December 16, 2009: 4:15 PM
Room 103, First Floor (Convention Center)
I report on the results of several recent studies in my research group that reveal limitations on geographic range change under climate change. Poleward range shifts are considered key to the preservation of species under climate change. In a study led by Shannon Pelini, we performed a field and laboratory translocation experiment on two species of co-occurring butterflies with contrasting life history characteristics (Erynnis propertius and Papilio zelicaon). We found that the impacts of warming affected peripheral populations of the two species differently. Fitness in E. propertius at the range edge was increased under summer warming but decreased under winter warming; in P. zelicaon, mean warming did not increase peripheral populations and extreme warming caused fitness declines. In both species, interactions with host plants are likely to be important in future range shifts because host plants of E. propertius are geographically limiting and hosts of the P. zelicaon change in relative quality under a warming scenario. In complementary experiments on range change in the hosts of P. zelicaon, led by Travis Marsico, we found that dispersal limitation plays a key role in setting northern range boundaries, suggesting that future range change of both plants and butterfly could be limited by the natural colonization of plants.