Help! A robin is hitting my window!
Image: Ann Cook

The Questions
Every year people write to Journey North asking for help because a bird — usually a robin — is flying into their window, patio door, or car mirror, over and over and over. The people are sometimes irritated by the noise, and usually worried about the bird. The window often gets smeared with feathers and even blood. What are these robins doing? What can we do to stop this behavior?

The Story
When American Robins start feeling territorial each year, they do their best to keep other adults of the same sex outside of their territorial boundaries. When a territorial robin notices its reflection in a window or mirror within its territory, it gets agitated, raises the feathers on its head, and assumes a dominant posture. Normally that is enough to make any other robins leave the territory immediately. But instead of flying away, the reflected robin seems to get equally agitated, raises its head feathers, and gets in an equally dominant posture. The first time this happens, the real robin often just leaves. If it's a male, he often goes to his favorite song perch and starts singing. When he doesn't hear a responding song, he's more certain that this is really his own territory. If it's a female, she goes back to her daily activities and stays on the lookout for other females.

If the robin sees that reflection again, it gets more and more agitated — but so does the reflection! Finally, the robin flies in to chase the other robin away. But the reflection flies in exactly the same way, and the robin hits the glass. And the reflected robin STILL doesn't leave! No matter how aggressive the real robin gets, and no matter how hard it fights, the reflection matches it. The real robin becomes more and more determined to drive that upstart away!

The Answer
Robins are not stupid. But during the nesting season their territorial urge is even more powerful than their urge to eat or sleep. Defending their territory is the way they ensure there will be enough food for their babies. No wonder they work so hard!

But the whole time the robin is fighting its reflection, it is NOT doing the things that will really ensure its babies' survival. It needs to eat, sing (if it's a male), build a nest, incubate eggs (if it's a female), and chase REAL robins away. How can we help it stop this behavior?

The only way to do this is to break the reflection. Fortunately, we don't have to break the window to do this! The simplest way, if it's a small window or mirror, is to simply tape some paper or cardboard over it, on the outside. Usually the paper needs to be up for three or four days until the robin gets busy enough with other things to forget about the "intruder." If it's a big patio window, it's harder to cover the whole thing. One technique that sometimes works is to paper over the area where the robin has been actually hitting, and then hang shiny helium balloons nearby. Most birds are frightened of helium balloons, probably because they act so different from things birds encounter in nature: they seem to fall up!

Try This! Vocabulary Stretcher!
Look up the word escalate in the dictionary. What does it mean? How does escalate relate to a robin's behavior when it is fighting at a window? Write a sentence about robins using the word escalate.

National Science Education Standards

  • The behavior of individual organisms is influenced by internal cues (such as hunger) and by external cues (such as a change in the environment).
  • Behavior is one kind of response an organism can make to an internal or environmental stimulus.
  • An organism's behavior patterns are related to the nature of that organism's environment, including the kinds and number of other organisms present, the availability of food and resources, and the physical characteristics of the environment.