Wildlife warning reflectors do not mitigate wildlife–vehicle collisions on roads

  • Published source details Benten A., Hothorn T., Vor T. & Ammer C. (2018) Wildlife warning reflectors do not mitigate wildlife–vehicle collisions on roads. Accident Analysis & Prevention, 120, 64–73.


This study is summarised as evidence for the following.

Action Category

Install wildlife warning reflectors along roads

Action Link
Terrestrial Mammal Conservation
  1. Install wildlife warning reflectors along roads

    A replicated, controlled study in 2014–2017 of 151 road sites in central Germany (Benten et al. 2018) found that four types of wildlife warning reflector did not reduce wildlife-vehicle collisions. The number of vehicle collisions was similar with and without four types of wildlife warning reflectors for three groups of mammals: deer (roe deer Capreolus capreolus, red deer Cervus elaphus, fallow deer Dama dama); wild boar Sus scrofa; and other mammals (badger Meles meles, red fox Vulpes vulpes, hare Lepus europaeus/rabbit Oryctolagus cuniculus, wildcat Felis silvestris, racoon Procyon lotor). Data are reported as statistical model results. Three types of wildlife warning reflectors were installed along 151 stretches of road (average 2 km long): dark-blue reflectors (51 sites); light-blue reflectors (50 sites) and multi-coloured reflectors (50 sites). In addition, one type of reflector (transparent/silver) with an acoustic warning (1.5 second sounds triggered by vehicle headlights) was installed along a 200 m stretch of road at 10 of the 101 sites with blue reflectors. Reflectors were installed on posts (55–100 cm high) spaced 25–50 m apart. Wildlife-vehicle collisions reported to the police (1,984 in total) were analysed for 12 months with the reflectors installed and 12 months without in 2014–2017.

    (Summarised by: Anna Berthinussen)

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