land Article Sustainable Landscape Planning to Mitigate Wildlife–Vehicle Collisions Ancuta Fedorca 1,2,† , Mihai Fedorca 1,2,† , Ovidiu Ionescu 1,2 , Ramon Jurj 1 , Georgeta Ionescu 1 and Marius Popa 1,2, *   Citation: Fedorca, A.; Fedorca, M.; Ionescu, O.; Jurj, R.; Ionescu, G.; Popa, M. Sustainable Landscape Planning to Mitigate Wildlife–Vehicle Collisions. Land 2021, 10, 737. https://doi.org/10.3390/ land10070737 Academic Editors: Christine Fürst and Ileana Pătru-Stupariu Received: 11 June 2021 Accepted: 12 July 2021 Published: 14 July 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1 Wildlife Department, National Institute for Research and Development in Forestry Marin Dracea, 077190 Voluntari, Romania; ancutacotovelea@yahoo.com (A.F.); mihai.fedorca@yahoo.com (M.F.); o.ionescu@unitbv.ro (O.I.); ramon@icaswildlife.ro (R.J.); titi@icaswildlife.ro (G.I.) 2 Silviculture Department, Faculty of Silviculture and Forest Engineering, Transilvania University of Bras , ov, 500036 Bras , ov, Romania * Correspondence: mmp4444@gmail.com; Tel.: +40-742-120-175 † Ancuta Fedorca and Mihai Fedorca are equally contributing authors. Abstract: Road development, traffic intensification, and collisions with wildlife represent a danger both for road safety and species conservation. For planners, deciding which mitigation methods to apply is often problematic. Through a kernel density estimate, we analyzed 715 crossing locations and wildlife–vehicle collisions (WVCs) involving brown bears, lynx, wolf, red deer, roe deer, and wild boar in the Southeastern Carpathian Mountains. We identified 25 WVC hotspots, of which eight require urgent mitigation of existing infrastructure. Moreover, many of these hotspots are in Natura 2000 sites, along road sections where vegetation is in close proximity, animal movement is the highest, and driver visibility is low. Our study is the first in Romania to recommend practical solutions to remediate WVC hotspots and benefit sustainable landscape management. Keywords: traffic; wildlife–vehicle collisions; infrastructure; safety 1. Introduction Natural populations and habitats are affected by roads in numerous ways, such as wildlife–vehicle collisions (WVCs), gene flow restrictions, and decreased landscape con- nectivity [1,2], especially in combination with habitat loss and land-use changes [3]. The frequency of wildlife–vehicle collisions is likely to increase as road networks and traffic volume continue to expand [4,5]. Moreover, species diversity and abundance near roads decrease with increasing traffic volume [6,7]. Many studies over time found that WVCs were not random but spatially clustered [8,9], and their probability was mainly predicated on accident datasets [10,11], wildlife move- ment data [12], expert opinion, literature-based model [13], or landscape-based approaches for delineating hotspots [14]. Other methods have applied clustering approaches [15,16] or assessed roads based on segments of equal length, with WVC data aggregated later [17,18]. Recent techniques have used fatality-based habitat identification and characteriza- tion [19], whereas kernel density estimation (KDE) remains the conventional spatial element for hotspot clustering [16,20,21]. Important causes of WVCs were identified in previous studies, such as road characteristics, traffic volume, visibility, and intersections [11,22,23]. Nevertheless, the driving forces behind mitigation efforts were human safety and eco- nomics [20,21]. Given the existing tools and methods, new infrastructure could benefit from spatial mapping, connectivity models, and explicit guidelines [22], so that road administrators can implement long-term cost-effective mitigation measures with multiple benefits [23]. Identifying wildlife road-crossings and wildlife–vehicle collisions hotspots should become priority preventive measures [4,24]. If an area is of high importance for wildlife crossing and a collision hotspot, that is where mitigation efforts should begin [25,26]. Land 2021, 10, 737. https://doi.org/10.3390/land10070737 https://www.mdpi.com/journal/land