SREL Reprint #3175

Can invasive Burmese pythons inhabit temperate regions of the southeastern United States?

Michael E. Dorcas1, John D. Willson2, and J. Whitfield Gibbons2

1Department of Biology, Davidson College, Davidson, NC 28035-7118, USA
2Savannah River Ecology Laboratory, Aiken, SC 29802, USA

Abstract: Understanding potential for range expansion is critical when evaluating the risk posed by invasive species. Burmese pythons (Python molurus bivittatus) are established in southern Florida and pose a significant threat to native ecosystems. Recent studies indicate that climate suitable for the species P. molurus exists throughout much of the southern United States. We examined survivorship, thermal biology, and behavior of Burmese pythons from South Florida in a semi-natural enclosure in South Carolina, where winters are appreciably cooler than in Florida, but within the predicted region of suitable climate. All pythons acclimated to the enclosure, but most died after failing to seek appropriate refugia during sub-freezing weather. The remaining snakes used refugia but died during an unusually cold period in January 2010. Although all snakes died during the study, most survived extended periods at temperatures below those typical of southern Florida and none exhibited obvious signs of disease. Our study represents a first step in evaluating the results of climate matching models and we address factors that may affect range expansion in this invasive species.

Keywords: Everglades National Park, Invasive alien species, Python molurus bivittatus, Range expansion, Risk assessment, Thermal biology

SREL Reprint #3175

Dorcas, M. E., J. D. Willson, and J. W. Gibbons. 2011. Can invasive Burmese pythons inhabit temperate regions of the southeastern United States? Biological Invasions 2011(13): 793-802.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).