Bird-glass collisions kill an estimated 600 million birds annually in the US alone. Prevention through building design, window treatments, and urban planning changes represents a significant welfare opportunity.
Bird-glass collisions cause acute traumatic injury and death on a massive scale. Individual birds that survive initial impact often die from internal haemorrhage, brain injury, or shock within hours. The welfare scale of the problem is extraordinary given the cumulative annual mortality. Prevention is technologically straightforward but requires commitment from building owners, architects, and urban planners. Glass treatment products and design features that make glass visible to birds are widely available and effective when applied correctly. New building design standards incorporating bird-safe glass requirements — now adopted in some jurisdictions — prevent the problem at source. Existing buildings can be retrofitted with window films, decals, and external screens. Individual householders applying deterrents to home windows contribute meaningfully to cumulative collision reduction.