Window Collisions and Bird-Safe Windows

Every year, 600- 900 million birds die due to window collisions in the United States. We can prevent these window collisions by using methods that make windows visible to birds.

To learn more, click here for a video or scroll to the bottom of the page for Frequently Asked Questions.

For more information on the best ways to make your windows bird safe click here, or for direct assistance email Research Coordinator Ava Landgraf at

What is Detroit Audubon doing?

Detroit Audubon is currently focusing our efforts on implementing bird-safe window retrofits for buildings on the Wayne State University campus. Detroit Audubon has been surveying the buildings around the Wayne State campus for the past five years to see which buildings result in the most window collisions. By using this data, and considering feasibility and outreach value, we selected two sections of windows that will have the highest impact for reducing window collisions and creating opportunities to educate people about these collisions. Detroit Audubon is partnering with Wayne State University and Detroit Zoological Society to install bird-safe window retrofits and educational signage regarding bird-safe windows and window collisions in 2023.

Report a Window Collision

If you find a bird (injured or deceased) that appears to have hit a window or building, please take a picture and report the incident to Global Bird Collision Mapper at You can easily register and then report any collision incident and where the bird was found. This information is extremely helpful to better understand bird collisions and especially to Detroit Audubon in order to determine which buildings are most problematic. 

Frequently Asked Questions about Bird-Window Collisions

Why do birds fly into windows?

Birds hit glass and other reflective surfaces for two main reasons: 1) Birds see the reflection of the sky or vegetation in the glass and try to fly to it, and 2) Birds see the sky or vegetation on the other side of the glass and attempt to fly to it.

Why don’t birds “see” glass?

Both humans and birds have a hard time seeing glass. Many people have accidently walked into a glass door but usually we are able to use context clues to tell us when there is glass. We see streaks, cracks, window panes or the rest of the building and know, without thinking about it, that there is glass. Birds and most wildlife do not know the concert of glass and cannot use visual cues to see glass. If a bird hits glass and survives, it may learn to be cautious of that area, but it will not extrapolate to understand and avoid all glass. Furthermore, when a bird hits glass it is very different from a human running into glass. On average, birds travel at much faster speeds than people. They are also much smaller than people and have hollow bones far more susceptible to breaking and fatal injuries

Why don’t we see more dead birds around glass?

Many people are surprised by the number of birds killed from window collisions because they rarely ever find a dead bird at their window. Studies have shown that many birds will not die instantly from a window collision, but instead suffer an injury that becomes fatal. Many collision victims face a broken bone or head trauma and in their weakened state they are unable to feed or become an easy meal for a predator. Even when a bird is killed on impact we rarely see them because a scavenger or urban predator – such as a rat, cat, raccoon – finds them first. Some predators have even learned to patrol windows and wait for these easy meals during dusk and dawn when birds are most active.