Wild birds face mortality from human-made structures and animals at enormous scale. Window strikes, domestic cat predation, and energy infrastructure cause billions of bird deaths annually.
Wild bird mortality from human infrastructure and domestic cats represents a massive aggregate welfare harm that is amenable to practical mitigation at multiple scales. Individual window strikes cause acute trauma — broken wings, brain injury, and prolonged dying — that is preventable through bird-safe glazing films and netting. Domestic cat predation can be reduced through indoor or supervised outdoor access. Infrastructure-related mortality requires policy intervention: bird-friendly building codes, power line insulation, and wind turbine siting away from migration corridors. The scale of these harms — billions of birds annually — makes effective mitigation one of the highest-impact available wild animal welfare interventions. The good news is that many effective solutions exist and are being adopted in some jurisdictions.