Wildlife Road Mortality: Scale, Welfare and Mitigation

How road infrastructure kills and injures billions of wild animals annually and what evidence-based mitigation measures reduce mortality.

Key Facts

An estimated one billion terrestrial vertebrates are killed on roads globally each year — making road mortality a leading cause of wildlife death
In the UK, approximately 100,000 hedgehogs, 50,000 deer and 3,000 badgers die on roads annually
Road mortality disproportionately affects species with low reproductive rates — badgers, raptors and larger mammals suffer most demographically
Wildlife crossing structures (underpasses, green bridges) reduce mortality by up to 90% at targeted high-risk road segments
Road lighting at night disorients moths and other night-flying insects, compounding the direct mortality from vehicle strikes
Animals struck but not killed on roads experience injuries including fractured limbs, spinal trauma and internal haemorrhage — welfare harm extends beyond mortality

Welfare Considerations

Road mortality causes welfare harm of two kinds: the acute suffering of collision injuries in animals that survive the initial impact, and the population-level distress of fragmented habitats that isolate social groups. A badger that has lost family members to road strikes may experience disrupted social bonds; a deer herd fragmented by motorway infrastructure loses the predator-detection benefit of group living. Animals that are wounded but not killed face prolonged suffering: a hedgehog with a broken pelvis cannot forage, defend itself or escape predators and will die slowly without intervention. Wildlife collision reporting networks and rapid response rescue services reduce the duration of this welfare harm when they operate effectively.

What You Can Do

Report injured wildlife on roads to your national wildlife rescue network — carry the contact number in your car
Drive at reduced speed at dawn, dusk and night in rural areas — these periods coincide with peak wildlife movement
Support local wildlife corridor mapping projects that identify high-mortality road segments and advocate for crossing structures
If you are involved in road planning or consultation, advocate for wildlife impact assessment and crossing structure funding
Install hedgehog-friendly gaps in garden fences — connected gardens reduce the pressure on hedgehogs to cross roads
Donate to organisations fitting GPS tags to badgers, deer and other species to map road mortality hotspots for mitigation planning