Bird Window Strike Prevention | Animal Welfare Hub

Window collisions kill hundreds of millions of birds annually in North America alone — and most are easily preventable.

Key Facts

An estimated 600 million birds die from window strikes annually in the United States alone
Birds cannot perceive glass as a barrier — they either see sky or vegetation reflected in it and fly toward it at full speed
The collision typically causes severe head trauma and internal hemorrhage — death may be immediate or follow hours later
Buildings with large glass areas including offices, homes, and transit stations are the primary sources of strikes
Simple, low-cost interventions including exterior window film, tape patterns, and external screens reduce strikes by 90%+
The American Bird Conservancy and similar organizations provide free guidance on collision prevention
Migratory birds are particularly vulnerable during spring and fall passage — urban areas with abundant glass represent gauntlets

Welfare Considerations

Window strikes cause an extraordinary amount of wildlife suffering that is almost entirely preventable. Each collision kills or seriously injures a bird through trauma that is acute but often not immediately fatal — birds who appear stunned on the ground after a strike may regain consciousness only to die hours later from internal hemorrhage. The suffering in the hours between impact and death is real and significant. The extraordinary scale of this harm — hundreds of millions of individual birds annually — multiplied by the low cost and high effectiveness of prevention measures makes window strike mitigation one of the best welfare-per-dollar interventions available to individual householders and building managers.

What You Can Do

Apply bird-safe window film or tape in 2-inch grid patterns on the outside of windows (patterns must be on the exterior)
Install exterior insect screens which provide a visible barrier that birds can perceive as solid
Move indoor plants away from windows to reduce the vegetation-reflection that attracts birds toward glass
Report your window strike prevention actions to the American Bird Conservancy FLAP database to contribute to impact data
Advocate for bird-safe building standards in your local planning and building regulation framework
If you find a stunned bird, place it in a ventilated cardboard box in a quiet, dark space and contact wildlife rehabilitation