Bird-window Collisions

 
 

Urbanization fundamentally changes ecosystem function and structure and has profound effects on wildlife populations. Birds that reside in urban settings face numerous human-related threats to survival, including mortality from bird-window collisions (BWCs).


Window glass is an invisible barrier to birds, and collisions occur as birds attempt to fly through what appear to be images of open space and vegetation.


Understanding the nature of BWCs is important because urbanization is accelerating faster than human population growth, and knowledge of how the urban environment affects bird survival is needed for conservation and management.


Previous work has demonstrated that the local drivers of BWCs are the amount of windows in buildings and proportion of habitat available to birds in urban areas (Hager et al. 2013). For example, buildings with high window area and levels of green space are patchily distributed across the urban landscape and both window area and development work in concert to create spatial variation in mortality.

Birds that reside in urban settings face numerous human-related threats to survival, including mortality from bird-window collisions (BWCs).

Research Program / Stephen B. Hager

Research Questions

  1. BulletWhat are the drivers of BWCs at local and regional scales?

  2. BulletIs there variation in drivers of BWCs among regions of North America?

  3. BulletDoes collision mortality affect the population health of affected species?

  4. BulletCan the factors that drive BWCs be used to model collision mortality across the urban landscape? 

  5. BulletCan models of mortality be used to inform conservation practices that minimize impacts resulting from window collisions?

Despite advances in our knowledge of how BWCs vary at small scales, we understand little about (1) the factors that influence BWCs at local and regional scales, (2) spatial variation in BWCs throughout North America, and (3) how BWCs work in concert with other factors to affect the population trajectories of affected species.

Current Research