Refining climate change projections for organisms with low dispersal abilities: a case study of the Caspian whip snake

• Published in: PloS one Vol. 9; no. 3; p. e91994
• Main Authors: Sahlean, Tiberiu C, Gherghel, Iulian, Papeş, Monica, Strugariu, Alexandru, Zamfirescu, Ştefan R
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 26.03.2014; Public Library of Science (PLoS)
• Subjects: Algorithms; Amphibia; Amphibians; Analysis; Animal Distribution; Animals; Biodiversity; Biology and Life Sciences; Case reports; Case studies; Climate Change; Climate models; Climatic analysis; Climatic conditions; Cost analysis; Current distribution; Dispersal; Dispersion; Earth Sciences; Ecological conditions; Ecological monitoring; Ecological niches; Ecological studies; Ecology; Ecology and Environmental Sciences; Ecosystem; Endangered & extinct species; Forecasting; Geographic information systems; Geomorphology; Global climate; Global temperature changes; Global warming; Models, Biological; Niches (Ecology); Organisms; Population Dynamics; Reptiles; Reptiles & amphibians; Snakes; Snakes - physiology; Species; Statistical analysis; United States > US; Oklahoma
• DOI: 10.1371/journal.pone.0091994
• ISSN: 1932-6203

Climate warming is one of the most important threats to biodiversity. Ectothermic organisms such as amphibians and reptiles are especially vulnerable as climatic conditions affect them directly. Ecological niche models (ENMs) are increasingly popular in ecological studies, but several drawbacks exist, including the limited ability to account for the dispersal potential of the species. In this study, we use ENMs to explore the impact of global climate change on the Caspian whip snake (Dolichophis caspius) as model for organisms with low dispersal abilities and to quantify dispersal to novel areas using GIS techniques. Models generated using Maxent 3.3.3 k and GARP for current distribution were projected on future climatic scenarios. A cost-distance analysis was run in ArcGIS 10 using geomorphological features, ecological conditions, and human footprint as "costs" to dispersal of the species to obtain a Maximum Dispersal Range (MDR) estimate. All models developed were statistically significant (P<0.05) and recovered the currently known distribution of D. caspius. Models projected on future climatic conditions using Maxent predicted a doubling of suitable climatic area, while GARP predicted a more conservative expansion. Both models agreed on an expansion of suitable area northwards, with minor decreases at the southern distribution limit. The MDR area calculated using the Maxent model represented a third of the total area of the projected model. The MDR based on GARP models recovered only about 20% of the total area of the projected model. Thus, incorporating measures of species' dispersal abilities greatly reduced estimated area of potential future distributions.