Wildlife road mortality in a plain landscape of high conservation value (Eastern Po Valley, Northern Italy)

Road infrastructures are one of the biggest manmade changes to the natural environment. They promote the loss of biodiversity in a constantly threatened world. This study set out to estimate the road mortality of vertebrates (roadkill) along two roads (the RA8 and Via Comacchio) in the Eastern Po River plain that lead from the city of Ferrara to the Northern Adriatic coast, crossing a territory rich in natural areas. The goals were to investigate which factors enhance or, on the contrary, reduce vertebrate mortality and ultimately to study possible mitigation measures that could help to contain the phenomenon. The RA8 is a highway used by high levels of trucks and cars, while Via Comacchio is a provincial road mainly used by local residents. The RA8 was affected by 46 roadkills (km -1 year -1 ). Via Comacchio was affected by 10 roadkills (km -1 year -1 ). The most important explanatory variables were the road morphology (such as the presence of underpasses and road barriers and the level of the road), the proximal habitat (such as rows of trees and reed beds) and the intensity of the traffic. Mitigation measures should focus on factors that decrease the numbers of casualties, for example underpasses, external fences and rows of trees. This kind of study could make it possible in the future to understand how to contain roadkill and how to decrease the ecological barrier effect of roads. Ecological, economic and road safety benefits could be relevant.