DO THIS, NOT THAT – Practical Steps to Preventing Window Strikes.

It probably happened to you at some time. You are at home, and you hear something that sounds like a soft thud in the background. You get up and investigate. Where did the sound come from? It sounded like it came from outside, but you look outside and see nothing. You step out your door and look around at eye level. Still nothing. Then as you come around the house you look down, and that is when you see it – a bird. It may be stunned, in which case you can ensure it is protected from predators by placing it in a box or paper bag and leaving it quietly to recover, which may take minutes or hours. More likely than not, however, it will be dead, and what is most heartbreaking is that it was an avoidable death.

Soon, the spring migration will be underway, so the likelihood of this occurring is much greater. A 2014 study by the US Fish and Wildlife Service and the Smithsonian Institution estimated that between 365 million to one billion birds are killed annually by building collisions in the U.S.

Why does this happen? During daylight hours, shiny glass exteriors confuse birds, who are unable to distinguish reflection from an open flyway. It may have even happened to you as you walked back from the pool and did not recognize that the sliding glass doors into your home were closed. Birds (and sometimes people) need clues on or around glass to warn them that it is there, and they are not moving into an open area. Collisions often occur repeatedly at the same window.

What can you do, as an individual homeowner?

Before we even address this, I presume that you are reading this article because you care and want to eliminate bird strikes on your property. All the effective solutions available will require you to balance your concern for the birds vs aesthetics, as all the solutions will affect your views from the windows you want to add protection to—some more than others. There are several effective solutions out there, so you’ll need to find the one that’s most aesthetically pleasing to you while still getting the job done. These solutions will probably not be required for every window in your home, but if you experience consistent collisions against several windows, you will want to address them. It’s easy to become confused with the many options available.

dead catbird

Now on to solutions. A good article on preventing collisions can be found on Audubon PA and the National Audubon Society. A longer guide can be found here. Also—click on “Quick Advice” to get a summary that is slightly longer than 1 page.

A general google search will reveal lots of good information. Simple solutions include creating patterns on reflective glass surfaces (Note that quantity and spacing matter: multiple markings 2 to 4 inches apart are recommended -one or two large stickers on a window will not work). Adding screens on the outside of windows will prevent injury. Window decals may help, but only if they are placed no more than 2-4 inches apart to be effective. Birds will try to fly through larger gaps. I personally opted for a dot pattern which is available from Feather Friendly that you can see in this image of my deck through the window. This coming spring the dot patterns will be available from Feather Friendly in rolls, which will make them very easy to apply. Right now, they are only available in strips, and their application is time consuming. I installed them on the large sliding glass doors to my deck 6 months ago, and to be honest, I don’t even notice their presence anymore. They do work very well.

I’m seeing more examples of decorative decals, on rolls, that comply with the requirements on spacing. Two examples are sold by Decorative Films and have been installed at both the Bronx and Philadelphia Zoos. They have an outdoor life of 7 years and are easily replaceable.

Bird Safety Film from Decorative Films

SX-BSFT Trellis Bird Safety Film

The Acopian Bird Savers system is a series of dark olive-green colored parachute cords hung vertically on the outside of the window four inches apart. According to Acopian, BirdSavers are unique in that most people find them “visually appealing and “elegant.” They can be purchased or made very easily by the homeowner. You can buy them at It is a very cost effective system because of its long life.

In addition to purchasing window protection, you can also show your support for birds by urging your federal representatives to support the Bird-Safe Buildings Act (H.R. 1986/S.971), re-introduced by Rep. Mike Quigley and Senator Cory Booker, to ensure that birds are protected from collisions with federal buildings.

Need to convince someone in your home? Peter Saenger, a researcher and expert on the subject from Muhlenberg College, provides details on the magnitude of the problem in his article Bird Collisions – The Numbers.

Birds are not a nice-to-have, they are a must-have for a healthy environment. Besides, who can imagine a beautiful spring day without the sounds of their singing? It would be a very quiet, very sad world.

Barbara Beck, Richland Township Bird Town Leader

Photography Credits:

First window image, Visitor’s Center of the Middle Creek Wildlife Management Area, by Christine M. Du Bois

Deceased Bird, by Jim Cubie, Acopian Center for Ornithology at Muhlenberg College

Image of deck, by Barbara Beck

Images of windows of applied products by Decorative Films LLC and Acopian BirdSavers