Wildlife Road Mortality: Infrastructure Solutions for Safe Animal Crossings

Road traffic kills billions of animals annually worldwide, but targeted infrastructure investments including wildlife crossings and road underpasses can dramatically reduce mortality.

Key Facts

Road vehicles kill an estimated 340 million vertebrates annually in the USA alone according to roadkill monitoring programs
Wildlife crossings including overpasses and underpasses have been shown to reduce large mammal road mortality by 80-90%
The Banff wildlife overpasses in Alberta Canada are among the most studied, with documented use by bears, wolves, cougars, and elk
Smaller culverts and underpasses under roads significantly reduce amphibian mortality during migration seasons
Speed reduction in areas of known wildlife road crossing reduces collision frequency and severity
Digital wildlife warning systems using animal detection sensors are being trialled in multiple countries as cost-effective alternatives to infrastructure

Welfare Considerations

Road mortality represents an enormous source of wildlife suffering and population decline that receives relatively little welfare attention compared to other human-wildlife conflicts. The suffering caused by vehicle strikes includes immediate fatal injury, prolonged dying after non-fatal collision, and orphaning of dependent young. Infrastructure solutions including wildlife crossings are not cheap but have strong cost-benefit profiles when road rebuilding or new road construction is already planned. Retrofitting existing roads with underpasses and fencing systems to guide animals toward safe crossings is increasingly being prioritised as an effective conservation and welfare investment.

What You Can Do

Support advocacy for wildlife crossing inclusion in all new road construction and major road improvement projects
Report wildlife road casualties to monitoring databases that inform infrastructure priority planning
Reduce driving speed in wildlife-rich areas and during dawn and dusk when animal activity peaks
Donate to organisations that advocate for and monitor the effectiveness of wildlife road crossing infrastructure