Friday, August 10, 2007
Exhibit Halls 1 and 2, San Jose McEnery Convention Center
Predicting the impacts of climate change on species distributions is a pressing problem for ecologists. Two general approaches have been taken to address this problem: climate envelop models and physiological models. Climate envelop models predict future distributions of species given contemporary associations between climate and species presence data. Physiological models predict potential species ranges given energetic and biophysical requirements of organisms. Both approaches can be implemented in a geographic context, but neither approach considers barriers to movements between current and future habitat patches. This is because both approaches examine the influence of climate change at a considerably larger spatial scale than the scale over which individuals actually experience or interact with the environment. Thus, it is unknown how the spatial arrangement of surface temperatures at a micro-scale may inhibit movements of organisms to compensate for climate change. Here, I demonstrate an approach to examine how changes in the magnitude and arrangements of surface temperatures at a micro scale can constrain movements under current and hypothetical climate scenarios. This approach integrates the use of spatially- and temporally- explicit maps of operative temperatures in conjunction with behavioral models of animal movement that incorporate decisions to maintain body temperatures within preferred ranges while maintaining energy balance. Insights from this approach will likely reveal that animals may not be able to simply compensate for temperature change by making simple shifts in latitude or elevation, but that habitat fragmentation will instead have potentially disruptive effects on movements.
