Symposium 18: Biological Invasions in a Time of Global Change
Organized by: J Weltzin and J Dukes
Thursday, August 7. 8:00 AM to 11:30 AM, SITCC Chatham Ballroom C.

Invasions as a consequence of climate-mediated range shifts.

Parmesan, Camille1, 1 University of Texas - Austin, Austin

ABSTRACT- Observed changes in natural systems, largely over the past century, indicate a clear global climate change signal. Even in the face of apparently dominating forces, such as direct, human-driven habitat destruction and alteration, this climate fingerprint implicates global climate change as a new and important driving force on wild plants and animals. Analyses of climate and of biotic change indicate that on a global scale, climate change has affected about half of the wild species studied (Parmesan & Yohe, 2003). One of the most prominent responses has been poleward and upward shifts in species' ranges, apparently tracking climatic shifts. In many parts of the world, this process has led to introductions of species into areas where they were previously absent, leading, in the short term, to local increases in species richness. Long-term effects are not obvious, as the outcome of interactions among novel and ancestral species are often difficult to predict. The evidence for this process occuring during recent climate change will be reviewed, and the implications discussed.

Key words: invasives, climate change, range shift, biodiversity