Why Do Birds Peck at Windows?

Bird and window interactions are rarely desirable. Occasionally a bird will fly up to one of your windows and peck at it vigorously, disturbing (or possibly amusing) anyone inside the house. And in ever worse instances, a bird will fly full-tilt into a pane of glass, stunning or killing itself, and leaving bloody feathers stuck to the window. Why do birds do this, and what can be done to stop them? The answers are fascinating.

Statistics

Though most people only experience a bird-and-window incident a few times a year, for the unlucky few it's much more common. Researchers estimate that over a hundred million birds are killed by flying into windows annually, in just North America alone. Simple pecking, though rarely deadly, is even more common---particularly in the early spring.

Defending Territory

But why do birds do it? The problem lies in the fact that birds can see reflections in the windows. If a bird sees its reflection, it believes it sees another bird. In the early spring, most birds are very territorial, and will attack anyone they believe to be an intruder. Because a bird establishing its territory is likely to stay in one place, a single bird's attacks can go on for days.

Clear for Flying

Even when birds don't voluntarily attack a window, they still will often accidentally collide with it. Again, this is because of reflections: birds can see the yard and trees outside of a window reflected inside, and believe that they can safely fly through. Unfortunately, such a mistake often ends in death or mutilation.

Altering Flight Paths

There are two main ways you can prevent birds from hitting your windows. The first is to stop them from flying near your windows in the first place, drastically reducing the chance of their being confused by reflections. If you have a birdfeeder near an often-hit window, take it down, or place the feeder somewhere else. Birds coming to feed may take off in the wrong direction, or see themselves in the window and move in for a battle. Stickers stuck to a window can also prevent accidental collision, by breaking up reflections and showing birds that a physical object is blocking their path.

Intimidation

The second approach is to frighten birds away. You can put an image of a large predatory bird, such as a hawk, in your window. This will be seen by smaller birds as too great a threat, and they will leave your window alone. Hawk statues or silhouettes can also be placed in nearby trees, to keep the birds at bay.

References

• Preventing Window Strikes
• Why do Birds Peck at Glass Windows?