Large carnivores shape road safety through effects on prey space use.

Presence of pumas reduces deer-vehicle collisions by up to 67% on the Olympic Peninsula, demonstrating a significant top-down effect on road safety.

• Why it matters: Understanding how large carnivores influence prey behavior and human safety addresses a critical gap in conservation and transportation management, promoting coexistence.
• What they did: Researchers analyzed camera trap and collision data across the region, using occupancy models to assess how puma presence alters deer habitat use and activity patterns over five years.
• The result: Findings show pumas cause deer to avoid high-traffic areas and shift activity to daylight hours, leading to substantial reductions in collision risk and enhancing road safety.