Glass has been around for nearly 3000 years, but it’s only been a bit over 100 years since the invention of sheet glass, making mass production of windows possible. Birds and windows have been in conflict ever since, if not before.
Every year at this time I get lots of questions on my website, www.ornithology.com asking why a certain bird is pecking at or flying into a window as if they were trying to get into the house or why birds are attacking their car’s side-view mirror, hubcap, or windshield. The simple answer is that the birds are attacking their own reflection.
In the spring, many male birds establish territories as the beginning of their breeding season, territories being necessary to protect resources like food and nest sites and attract a female. Naturally, they want to keep other males out, so they chase them away. Unfortunately, some birds are so aggressive and apparently not discriminating enough in evaluating the “intruder” that they attack their own reflection. The bird that seems to make a real habit of this is the Northern Cardinal of the Eastern and Southwestern U.S. Coming in second are the American Robin and the three species of bluebirds. Since cardinals, robins, and bluebirds are suburban species, it makes sense that they most often end up seeing their reflection in human-made objects. A smattering of other species such as towhees, wrens and titmice participate in this activity.
In the past, it was thought that a bird attacking a window was a sign of an imminent death in the household and that the bird was coming to lead the soul of the dead person to the afterlife. Some people still express fear at the thought of a bird entering their home, although I can’t imagine anything ominous resulting from that.
So what do you do if you have a bird tapping and flapping at your window at 6am?
Here are some suggestions. Eliminate the reflection by covering the window with cloth or soaping it. Put objects in or on the window that make it seem impassible – mylar strips, decorative window films or decals, tape, etc. Or block access to the window with a screen, a frame of netting, or a plastic covering.
Birds rarely suffer serious injury from this futile behavior which will stop after nesting is over. More serious are the collisions of birds with windows in homes and office buildings, especially tall ones. There are no exact figures, but good estimates from 40 years of collecting data tell us that at least 100 million and perhaps one billion birds are killed by colliding with windows in the U.S. In Chicago, for example, one tall skyscraper might be responsible for 2000 or more bird fatalities. There is no easy solution at
present to the problem that would be acceptable to most people who live in these homes and offices.
Wind turbines, microwave towers, and power lines are also hazards to birds that I’ll address in another blog.