Short communication Traffic mortality and the role of minor roads Frank van Langevelde a, * , Coby van Dooremalen b , Catharinus F. Jaarsma c a Resource Ecology Group, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands b Animal Ecology Group, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands c Land Use Planning Group, Wageningen University, Gen. Foulkesweg 13, 6703 BJ Wageningen, The Netherlands Received 30 August 2006; received in revised form 24 August 2007; accepted 14 September 2007 Available online 20 February 2008 Abstract Roads have large impacts on wildlife, as they form one of the principal causes of mortality, and disturbance and fragmentation of habitat. These impacts are mainly studied and mitigated on major roads. It is, however, a widespread misconception that most animals are killed on major roads. In this paper, we argue that minor roads have a larger impact on wildlife with respect to habitat destruction, noise load and traffic mortality. We use data on traffic related deaths in badgers (Meles meles) in The Netherlands to illustrate that traffic mortality is higher on minor roads. We ask for a more extensive investigation of the environmental impacts of minor roads. Moreover, we argue that the success of mitigation on roads drastically increases when both major and minor roads are integrated in the planning of traffic flows. Therefore, we propose a strategy based on the concept of a ‘‘traffic-calmed area’’. Traffic-calmed areas create opportunities for wildlife by decreasing limitations for animal movement. We ask for further studies to estimate what size traffic-calmed areas should be to maintain minimum viable animal populations. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Habitat fragmentation; Mitigation; Road ecology; Traffic and road characteristics; Traffic-calmed area 1. Introduction Roads have large impacts on wildlife, as there are at least four negative effects of roads and their traffic on wildlife (Van Langevelde and Jaarsma, 2004): destruction or alteration of habitat due to construction, disturbance of habitat along the road (noise, vibrations, car visibility, etc.), barriers created by the road (increased resistance for movement), and barriers by traffic (collision risk during crossing). The barrier and mortal- ity effects of roads may influence animal populations, e.g., insects (Vermeulen, 1994), reptiles and amphibians (Hels and Buchwald, 2001; Aresco, 2005a), birds (Clevenger et al., 2003), and mammals (Lankester et al., 1991; Clarke et al., 1998; Huijser and Bergers, 2000). Collisions with traffic mortality are considered to be among the major causes of death for many of these animals in human-dominated land- scapes (Groot Bruinderink and Hazebroek, 1996; Forman and Alexander, 1998; Philcox et al., 1999; Trombulak and Frissell, 2000), and for some species, it is the most likely cause of regional extinction (e.g., badgers, Lankester et al., 1991; Clarke et al., 1998). Notably, these negative effects of roads on wildlife are studied mainly on major roads (e.g., Kanters et al., 1997; Forman et al., 2003). It is, however, a widespread misconception that most animals are killed on major roads (Seiler, 2002). In this paper, we argue that the remaining road network, i.e., minor roads, has a larger impact on wildlife with respect to habitat destruction, noise load and traffic mor- tality. We use data on traffic related deaths in badgers (Meles meles) in The Netherlands to illustrate that traffic mortality is higher on minor roads (example 1). For reasons of declining biodiversity (Seiler, 2002; Forman et al., 2003) and risks of accidents (Garret and Conway, 1999), mitigation is frequently applied to reduce barriers to animal movement and traffic mortality. These interventions include keeping wildlife off the road (e.g., fences: Romin and Bissonnette, 1996; Putman, 1997; Aresco, 2005b), providing alternative routes (e.g., fauna passages and ecoducts: Keller and Pfister, 1997; Jackson and Griffin, 1998), or reducing the risk of collisions (e.g., highway lighting or mirrors: Romin * Corresponding author. Tel.: þ31 317 484750; fax: þ31 317 484845. E-mail address: frank.vanlangevelde@wur.nl (F. van Langevelde). 0301-4797/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.jenvman.2007.09.003 Journal of Environmental Management 90 (2009) 660e667 www.elsevier.com/locate/jenvman