How to stop birds from flying into your windows, according to experts
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For many of us, the sound of a bird crashing into a nearby window might be an unfortunately common occurrence. As unpleasant as it is to think about, hundreds of millions of birds die annually due to window collisions, but there is something we can do about it. While large-scale construction changes can have the largest impact, everyday homeowners and apartment dwellers can take a few small steps to help prevent bird collisions at home.
Applying window decals is one way to help prevent window collisions, but they must be installed properly. Dr. Christine Sheppard, director of the glass collisions program at the American Bird Conservancy, says that you can use any kind of decal — or anything that will stick to the window, for that matter — as long as you keep a few things in mind.
Your visual markers must be large enough for birds to see. Dr. Sheppard recommends decals at least 1/4-inch wide and says that bigger is better because birds can see them from farther away.
Opaque decals are best because translucent ones are harder for birds to see.
Regardless of the size of the decals, they should be spaced no more than 2 inches apart. This spacing creates a visual barrier, as birds will consider the two inches between decals too small to fly between, so they won’t attempt it.
Research shows that visual markers should be installed on the outside surface of the glass, meaning you have to install the decals outside, not inside. If the decals are installed indoors, then reflections could make decals invisible to birds.
Keep in mind that each product typically comes with its own set of instructions, which you should read before installing it. Some window decals don’t come with directions, and if they don’t, you’ll usually want to clean the exterior of the window before applying the clings to the wet surface. Then you’ll want to press them down to squeeze out all the air bubbles. Because common window cleaners can leave a residue that makes it hard for decals to stick, Sheppard recommends washing windows with just water or with water and a small amount of alcohol.
Now that you have the basics of installing bird window decals, here is a selection of window decals, along with some do-it-yourself options and other suggestions to prevent bird collisions at home or in the office.
Window decals to prevent bird collisions
Petallo Hummingbird Window Clings
These simple double-sided window decals are easy to install, and they stay adhered to the glass despite wind and rain. The set comes with twelve vibrantly colored hummingbirds that you simply peel off and adhere to the exterior of a clean window. I tested these window clings at my mother’s home and found that they were the easiest to install, and they tied with the Yovvky tree branch decals for staying on the best.
Yovkky Spring Summer Tree Branch Bird Strike Window Clings
The Yovkky tree branch and bird decals are, by far, the most complicated decals on this list to install, but they are also the prettiest. The difficulty comes from the nature of the design, a complex set of tree branches, leaves, buds and birds that stretch across nine pages. The product does come with a corresponding picture guide that shows how and where to place the decals from each page, but I found the process a bit overwhelming. Instead, I peeled off the two-sided clings and put them up as I saw fit, ensuring no more than 2 inches were between the decals. The result was absolutely beautiful, and it covers a larger area than the Petallo decals.
Yovkky Farmhouse Eucalyptus and Tulip Window Clings
Like Yovkky’s tree branch and bird decals, this set of window clings is an effective and attractive way to decorate a window to prevent bird collisions. What’s nice about this set is that, unlike most decals, which are limited to birds, this set is made up of eucalyptus leaves, old-fashioned trucks, mason jars, bicycles and tulips. The design is two-sided, so though you’ll need to install the decals on the window’s exterior, you’ll also enjoy them indoors. Because the design is less intricate than the tree branch version, they are also much easier to install.
Boao Assorted Leaf Bird Window Decals
This set of assorted leaf decals — which come in sets of 20 or 40 — is another stick-and-peel option to help prevent bird (and people) collisions with windows. This set does have installation directions, but they are only on the Amazon product page; they don’t come printed with the decals. The decals are semitranslucent, and according to the manufacturer, they reflect ultraviolet sunlight as a warning sign to birds. That said, our expert, Dr. Sheppard, recommends opaque decals over translucent. Also, while the directions may say to allow no more than 6 inches between decals, as previously mentioned, bird experts suggest placing the decals no more than 2 inches apart to prevent birds from attempting to fly between the decals. I also tested these window decals and found that, though they were a bit harder to pull off and install than other models, they did stick to the glass quite well.
Eacilles Hummingbird Static Window Clings
This 20-piece set includes five different styles of bird, and each decal is about 4 to 7 inches long. The semitranslucent decals are made with a translucent prismatic vinyl that captures sunlight. Though the manufacturers says that the decals will transform this sunlight into rainbows that reflect into your room, this wasn’t my experience when testing them. This could be because the manufacturer states (incorrectly) that the decals can be applied inside or outside, and the images on Amazon show the decals installed on the interior of the window. While installing them indoors in order to create a rainbow-like effect in your home might be pretty, it is not the best way to prevent bird collisions. To do so, be sure to install the decals on the outside of the window.
Though most reviews are fairly positive, some users complain that the decals do not stick well to the window, which was also my experience when testing them. They repeatedly fell off over the month I had them installed, which didn’t happen with any other brand I tested.
Window tape, paint and markers to prevent window collisions
Paul Groleau, the vice president of FeatherFriendly, which offers DIY, commercial and professional long-term solutions to prevent bird collisions, says that some window decals offer a false sense of security. For instance, some products don’t offer directions on proper placement, so they are improperly installed and only offer minimal protection. Other birds of prey decals, such as the widely available but largely ineffective hawk stickers, imply that birds will be too scared to fly into the window, though birds only see the images as black blobs because they don’t actually see hawks. Groleau adds that UV decals must be replaced every four to six months as the UV dissipates. Does this mean that bird decals are ineffective altogether? Certainly not, but if they are not installed properly and replaced frequently enough, they simply won’t be effective.
Groleau says that, if you’re unable to afford (or not yet ready to take the plunge) to install the more effective long-term anti-collision solutions that FeatherFriendly offers, he suggests trying bird tape, paint pens and markers.
FeatherFriendly ABC BirdTape
This American Bird Conservancy-approved tape comes in two styles, a 3/4-inch tape or 2-inch squares. In either case, the tape is applied to the exterior of clean windows, ideally on a day when the temperature is above 50 degrees Fahrenheit (10 degrees Celsius) and when there is no precipitation. The squares can be placed on the windows individually, and the tape can be cut as long or short as needed. In addition to spacing the tape two inches apart, FeatherFriendly provides suggested patterns that are the most effective, such as vertical or diagonal stripes across the windows.
FeatherFriendly Pro-DIY Dots for Fly-Through
These dots are a less-expensive, professional-quality solution if you want to maximize protection for birds without having to pay for professional installation. Dr. Sheppard of the American Bird Conservancy recommends these dots by FeatherFriendly, as they cover the least amount of glass while offering maximum protection. Though she says that larger (and cheaper) decals are fine, they are typically quite large, so when spaced 2 inches apart, they cover a lot of glass. Some also have to be replaced frequently, which brings up the long-term cost. These Pro-DIY dots cover are large enough that birds can see them but small enough that your window is not obstructed. As they are professional-quality, they are a long-term solution. The dots come on a sheet, so to install, you simply press the sheet on the glass and remove the backing, which leaves behind just the dots.
Akarued Acrylic Paint Pens
Available in white, red, gold, silver and black, these acrylic paint pens are designed to be used not on paper but on metal, stone, wood, canvas and glass. They can be used to draw unique and one-of-a-kind designs directly onto windows to prevent bird collisions. These nontoxic, water-based markers are easy to use, but if you use them instead of decals, ensure that the images drawn are large and no more than 2 inches apart. Also, keep in mind that darker colors will be more easily seen by birds.
Dixon Phano China Markers
These multipurpose marker-pencils can be used to draw in notebooks, create art on wood or stone, mark up your car’s windshield and tires or create window art to prevent bird collisions. The marker-pencils are easy to use — you just draw right on the windows and peel away the point to sharpen them — but because the tips are so thin, it will take longer to create designs than the previously mentioned paint pens. That said, they have different alternate uses from the paint pens, so you may find them a better fit for your needs.
DIY options and other tricks to prevent window collisions
Heidi Trudell, an architectural consultant, window collision researcher and the operator of the Just Save Birds Facebook page, says that birdbaths and bird feeders should be moved as close as possible to windows (ideally less than 3 feet) to help prevent collisions. Though she recommends more long-term solutions (like FeatherFriendly dots) since they are the most effective and suggests the previously mentioned window markers are the next best option, she does offer a different kind of DIY option in a pinch. As a quick, short-term fix, she suggests making a very dense checkerboard pattern of Post-it notes on the window. Trudell adds that this is a last-resort scenario and should not be used in place of a more effective solution.
EdcX Pre-Shrunk Paracord
Trudell says that a good DIY project to help protect birds would be to use pre-shrunk paracord (which is essentially a thin nylon rope) to make something called acopian bird savers. You hang the cords a few inches apart in front of a window to break the window’s reflection, which is what birds are attracted to. Without that reflection, birds are no longer at risk of flying into the window. This simple yet elegant solution is so effective that a birding lodge in Costa Rica saw a 99% reduction in bird collisions after installing them in 2016. They made this video explaining how to install the paracords. Note that while the EdcX paracord comes in two dozen colors, the darker colors will be more visible and, thus, more effective than the light colors.
Songbird Essentials Heated Birdbath
Many portable birdbaths have flimsy bases that may not stand up to wind and snow, and if you live in a very cold climate (like I do), most birdbaths will freeze over during the winter. The Songbird Essentials heated birdbath solves all these problems by heating the water once the temperature drops below 32 degrees, and by having a sturdy base that can be moved right up next to the window. It comes with a 12-inch power cord, so you’ll likely need to purchase an outdoor-appropriate extension cord to reach your outlet.
Note: The prices above reflect the retailers' listed price at the time of publication.
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