Why Birds Attack Your Windows

Thwap! Thwap! Thwap! Nothing says summer like the maddening irregular percussion of a bird’s beak rapping repeatedly against your window, but why do they do it? To you, your windows appear transparent, but to belligerent birds in bright daylight, you may as well have tiled the exterior with mirrors. A robin looking at your house sees another robin looking back at him, and then, of course, they fight. Window attacks are different from bird strikes, the violent collisions that occur when a bird thinks your house is the sky and flies straight into it. Strikes are dangerous and often deadly for the birds involved. Territorial attacks are mostly just annoying for everyone, including the bird. If you tend to find your home beset by angry birds, there are some concrete things you can do. For starters, move any feeders away from windows to discourage visitors. Then stand outside on a bright afternoon and check your windows for glare. You can cover any offending surfaces with fine mesh netting or a drop cloth to disrupt the reflection, or apply one-way film to make the glass appear opaque from the outside. If you’re really desperate and have some time (and extra cash) on your hands, you can install shutters on the outside of the house. Unfortunately, covering one window may simply push your problem a few feet away. American robins in particular have been known to attack as many as 15 windows in a single house. A territorial bird can be very persistent, so the best course of action is to be patient and wait for the breeding season to end — usually around August. In the meantime, hang in there.