Nest box programs support cavity-nesting birds that have lost natural habitat. Providing appropriate boxes in gardens and on buildings significantly helps declining species.
Providing nest boxes is one of the most direct welfare and conservation contributions available to individuals and organizations in urban and suburban settings. Many cavity-nesting birds that once relied on old trees with natural holes have lost these sites to woodland management and urban development. Nest boxes directly compensate for this loss, allowing birds to breed successfully in habitats that would otherwise exclude them. The welfare benefit extends beyond breeding: birds that successfully raise young have better survival than failed breeders, and nest sites reduce the energy cost of nest-building. Maintaining boxes through annual cleaning prevents accumulation of parasites that would harm future occupants.