Window collisions kill an estimated one billion birds annually in the United States alone, making them one of the most significant human-caused bird mortality sources.
Birds that strike windows experience traumatic brain injury, internal bleeding, and death. Those not immediately killed may sit stunned for minutes to hours in a vulnerable state before dying or recovering. Brain trauma reduces subsequent foraging efficiency and predator avoidance even in apparent survivors. Each collision represents acute suffering that is entirely preventable with readily available window treatment products. The aggregate welfare impact of a billion bird-window collisions annually is enormous.