Road mortality is one of the leading causes of hedgehog death in the UK, with estimates suggesting 100,000-300,000 hedgehogs killed on roads annually. As hedgehog populations have declined by over 50% since 2000, road mortality represents a significant welfare and conservation pressure that warrants targeted mitigation.
Hedgehogs have a defensive response to threat that evolved before motor vehicles: they curl into a ball and rely on their spines for protection. This response, which works against most natural predators, is fatal against cars. Hedgehogs also travel significant distances nightly (1-2km) across roads that fragment their habitat. They are most active at dusk and dawnâcoinciding with reduced driver visibility. Their dark coloring provides no visibility advantage on road surfaces at night.
Citizen science programsâincluding PTES's "Mammals on Roads" survey and iRecordâmap road mortality hotspots, enabling targeted mitigation at identified high-risk sites. Data shows road mortality is not randomly distributed: certain road sections, junction types, and habitat configurations create disproportionate mortality concentrations.
Underpasses: Hedgehog-specific underpasses at identified crossing points allow safe road crossing. Effective design requires appropriate sizing (13cm diameter minimum), dry conditions, and guidance funneling hedgehogs to crossing points. Connectivity: Reducing the need to cross roads through garden connectivity (hedgehog highways) reduces exposure. Speed reduction: Lower vehicle speeds give hedgehogs more time to respond and reduce impact severity. Habitat management: Reducing attractants near roads (compost heaps, food sources) can shift hedgehog activity away from high-risk areas.
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