Window and glass collisions kill an estimated 600 million birds annually in the US alone, making collision prevention one of the most impactful individual wildlife welfare interventions available.
Bird-glass collision is one of the most pervasive and easily preventable sources of wild bird mortality — hundreds of millions of birds killed annually by structures that humans have created and can modify. The welfare impact on individual birds ranges from instant death to disorientation and delayed death from internal injury and predation following collision. Unlike many wildlife welfare problems that require systemic change, window collision prevention is directly actionable by individuals at low cost and with demonstrable effect. UV-reflective window films, properly spaced strike tape, external screens, and thoughtful positioning of bird feeders relative to windows are all effective, accessible, and affordable interventions. The aggregate welfare benefit of widespread adoption of these simple measures would be enormous.