Predicting elusiveness: potential distribution model of the Southern smooth snake, Coronella girondica, in Italy

Abstract

Predictive models of species distribution may be very useful for understanding actual distribution of elusive species, including several snakes. The southern smooth snake (Coronella girondica) is likely the most elusive snake species of peninsular Italy, and is therefore well-suited for predicting potential distribution studies. In this paper we predict the potential distribution map of this species in Italy by using MAXENT algorithm, that finds the probability distribution of maximum entropy that is constrained by considered ecological parameters. Presence data for Coronella girondica were gotten from CKmap. The potential distribution model of Coronella girondica showed a very good overall performance (AUC = 0.959), and indicated that high suitability areas correspond mainly to Tyrrhenian north and central regions, including Liguria, western Emilia-Romagna, Tuscany, Umbria, and northern Latium. Southern Italian regions were clearly unsuitable for this snake species. Overall, our study revealed that previous distribution maps indicating the occurrence of Coronella girondica in southern Italy and Sicily were poorly reliable. The conservation and management implications of our study are also addressed.