Cost benefit analysis to identify the best type and location for a wildlife crossing structure

• Main Authors: Francesco Del Greco, Clara Tattoni, M. Gibeau, Claudio Groff, Marco Ciolli
• Other Authors: Roberta Chirichella and Damiano G. Preatoni, Del Greco, Francesco, Tattoni, Clara, Gibeau, M., Groff, Claudio, Ciolli, Marco
• Format: Conference Object
• Language: English
• Published: Associazione Teriologica Italiana ETS 2022
• Subjects: Eia; Ursus arctos
• Online Access: https://hdl.handle.net/11572/365208; https://doi.org/10.13140/rg.2.2.36637.59368; http://www.italian-journal-of-mammalogy.it/pdf-150740-76387?filename=XII

Wildlife-vehicle collisions cause damages and loss for people and animals alike and are a reason of human wildlife conflict. Collisions are considered a consequence of the landscape fragmentation which is also a major cause of biodiversity loss world- wide. In Europe the most of the recorded accidents involves ungulates, and in Trentino (N Italy) a similar trend is observed. Since 2010, an average of 700 collisions per year have been reported between wildlife and vehicles (99% ungulates of which 77% roe deer) and a total of 6 collisions involved the brown bear (Ursus arctos arctos). Even if the number of accidents with bears is small, the size of the species poses a risk for the drivers and the loss of a bear individual can have a big impact on the small and isolated population of the South Eastern Alps. Wildlife crossing structures increase habitat connectivity and reduce up to 86% the number of accidents when appropriately designed and strategically placed. This work aims to identify the best type of structure and its location to reduce bear-vehicle collisions in the Province of Trento (PAT). The data used to perform the analysis includes: habitat suitability models and connectivity models for the brown bear available from literature, the wildlife vehicle collision geo database form the PAT, GIS layers about topography, land use, road network and human settlements. The analysis included a GIS assessment to overlap the main movement corridors, the hotspots of wildlife-vehicle collisions and the terrain features that allow the building of a crossing structure. After a field survey of three possible locations, Environmental Impact Assessment (EIA) and Cost-Benefit Analysis (CBA) were used to identify the best type of structure and its final location. The cost-benefit analysis was performed using prices and other economic values available from in literature for other countries. The GIS assessment identified the road SS45bis in “Valle dei Laghi” as an hotspot with some tract with more than 10 collisions per km in 9 ...