How many decals should I put on a window?

On an average size window, one decal should be enough. A sliding door or a large window may need two or more decals. The number needed will be determined by the placement of your bird feeders, the location of trees and shrubs, the way the light reflects on your windows, and various other factors.

Will the decal stop all bird collisions?

It has been estimated that as many as one billion birds die annually from hitting windows. Many of those are killed by colliding with lighted buildings while migrating at night. In the case of birds around our houses, no method is perfect, as nothing can prevent the panic flights caused by hawks and other predators. If you work in or near buildings that are left lighted at night, please help educate those who influence that decision.