Birds attacking windows

Here’s a question I received via email from Mike Flynn of Michigan:

"We have a female cardinal that is fervently trying to enter our house. She continues to gently fly against window tapping her beak, running up the window with legs and wings. This has been going on for several days and this morning has been non-stop, going to different windows around the house. I can stand in the window and she doesn’t seem concerned that I’m so close. Please let me know if you have any experience with this and are willing to share."

An excellent question! I have seen the behavior you’ve described in birds before. The cardinal is exhibiting a type of territorial behavior – it sees its own reflection and thinks it's an intruder, and not itself.

Last spring an American Robin spent a lot of its time and energy “attacking” side mirrors of cars in our parking lot at Eagle Optics. This behavior went on for several days, but eventually the robin moved on to other things - perhaps it gave up defending this particular territory.

We determined that the robin would become particularly feisty whenever cars were parked near a patch of trees along the road – perhaps it was considering it for a nesting site. We tried to avoid parking there, but this wasn’t always possible. It was in our best interest to do so because the robin wasn’t very discriminating about where it pooped! Other than parking our cars elsewhere, there wasn’t much we could do about the robin – it wouldn’t have been practical to go around covering up side mirrors of cars in our lot or along the road in front of our store.

Read what Cornell has to say (below) about covering your windows so the bird can no longer see its reflection. That should take care of it, or you can just wait the bird out...if you can put up with it!

Birds attacking windows (from Cornell’s website):

Many people become alarmed or annoyed when birds start attacking their windows in spring. The male cardinal pecking at your window is fighting what he perceives as an intruder and is simply defending his territory—he doesn't understand that it's his own reflection. In fact, both males and females may do this, especially species that often nest close to houses, such as American Robins, Northern Cardinals, Chipping Sparrows, and Song Sparrows.

Try covering the outside of the window with netting or fabric so the reflection is no longer visible. You can also try drawing soap streaks across the window to break up the reflection. This territorial reaction may be so strong that the bird may exhaust itself, but it usually doesn't result in fatal injury.

American Robin image © 2006 Mike McDowell