Wildlife

Bird Window Collisions: Scale and Prevention

Window and glass collisions kill an estimated hundred million birds annually in Europe alone, making them one of the most significant preventable sources of bird mortality.

Key Facts

An estimated 100-300 million birds die from window collisions in Europe each year
Windows are invisible to birds as they see reflections of sky and vegetation
Dawn and dusk are peak collision times corresponding to bird flight activity
Products including CollidEscape and Feather Friendly tape significantly reduce collision rates
Placing feeders very close to or very far from windows reduces collision risk

Welfare Considerations

Birds that strike windows often die immediately or suffer head trauma and internal injuries leading to delayed death. Survivors may be temporarily stunned and vulnerable to predation or secondary trauma. Prevention is straightforward and inexpensive relative to its impact. Widespread adoption of bird-safe glazing in new buildings and retrofitting of high-risk existing windows could prevent millions of deaths.

What You Can Do

Apply bird collision deterrent film or tape to high-risk windows
Place feeders either within 1m or over 10m from windows to reduce collision risk
Use patterned glass in new building construction in bird flight paths
Monitor for collision evidence and adjust deterrents if strikes continue
Report collision data to BirdLife International monitoring programmes