Living on the edge: habitat selection of <i>Hierophis viridiflavus</i>

Abstract

We analysed habitat choices of H. viridiflavus in a continental area of northern Italy and compared our results with those reported from central Italy by other authors. We used two different field techniques, visual encounter surveys (VES) and radio tracking (RT), and both pointed out a clear preference for edges, while uniform habitats (like mature woods or meadow) were avoided. The same pattern of habitat use is documented for other whip snakes and can be related to the high thermal quality of edges, although other factors could not be ruled out (e.g., prey/shelters abundance). Nevertheless, other researches on Mediterranean populations do not show such a preference, suggesting that at lower latitude habitat thermal quality is not the main constraint and H. viridiflavus can behave as a habitat generalist. Finally, comparing the two field techniques, we find that VES partially overestimates the importance of edge use, suggesting that caution should be used about its utilization to obtain information in this kind of research.