Window strikes: Stop the thudding!

Birds tend to collide with windows in rural yards with trees and birdfeeders—the very picture of bird-friendly habitat. The more birds that there are in the yard, and the more birds that are closer to a house and windows, the more likely that a collision is going to occur simply by sheer numbers. These are disturbing findings. Hanging birdfeeders and growing native plants are among the best ways to provide food, water, and shelter to birds as they migrate across an increasingly developed continent. If homeowners want to attract and provide refuge for birds, they must also safeguard their yards against threats such as windows, toxins, and cats.

The good news is that it’s not difficult to make your windows—and yard—safer for birds. Here’s a step-by-step guide to get you started:

Understand the Problem
People take windows for granted; we don’t even think about them. When we see a framed patch of green leaves on the outside of a building, we intuitively understand that it’s an illusion—a pane of glass reflecting a nearby tree—if we notice it at all.
Birds cannot make this distinction. If they’re flying straight towards a glass window, they won’t see it. Ever. What they see are the reflections of habitat or sky, things they know and need.

Take a Bird’s-Eye Tour of Your Home
Now that you know what a bird can’t see, stroll around your house and observe it from their perspective. Identify windows that reflect sky or greenery at certain times of day, or those that provide a clear view inside to what looks like nice habitat, such as houseplants or a water feature. If you find evidence of a window collision (like a dead bird or smears from feathers or blood), make that window a top priority.
The occasional collision might not seem like a big deal, but just one or two collisions per house per year can mean that hundreds of millions of birds are dying annually.

Relocate Your Feeders
Many people hang birdfeeders in a tree close to their house so they can easily watch the birds from a window. This is the worst place to put them. It draws birds close to windows while also giving them space to gain the necessary flying speed to hurt themselves. Your options are twofold: Place feeder and birdbaths within three feet of the nearest window so that birds don’t hurt themselves upon liftoff; or place them more than 30 feet away so that feeding birds have plenty of space to clear the house.

Put Some Strings On It
Hanging strings, ribbons, or cords in front of your window is an inexpensive way to help birds avoid your windows. All you need is some medium-weight string (too heavy and birds might get tangled up) and a pair of dowels. Hang one dowel horizontally above the window; tie a piece of vertically hanging string to the dowel every four inches; and tie the ends to the other dowel to weigh the string down.
The real beauty of a solution like that is you can put them up whenever you need them as bird collisions tend to cluster around certain times of year, particularly during migration and when chicks are fledging. Once you identify those months with heavy bird traffic in your yard, you can hang and remove the string accordingly.

Don’t Clean Your Windows
Looking for an excuse to avoid your chores? Blame the birds. Dirty windows are less reflective and can reduce collisions. If you’re going to wash windows, wash them after the majority of migrants have moved through.

Use a Lot of Decals
Many forest birds readily dart between branches and leaves, so a single decal will not deter them. The barrier needs to be dense, as if it were impenetrable foliage. What you’re trying to do is create enough of a pattern that a bird says: No, I’m not going to fly through there; I’m going to fly around instead.
A single decal of a hawk stuck to a window is a common sight, but they don’t fool birds into thinking they’re heading toward a real predator. One hawk decal in the middle plus four more could make a bigger difference.

Think Beyond Windows
If you hang feeders or otherwise invite birds into your yard, you need to make sure you’ve considered all threats. Lights directed upward can disorient birds when they migrate at night, so make sure any exterior lights are covered. Don’t use pesticides or other toxins on your property that could injure or kill birds. And while windows are a big problem, they come in second to cats as the biggest killers of migrating birds. You absolutely cannot have free-roaming cats in the yard and put bird feeders up–that includes your neighbor’s cats, too.

American Bird Conservancy has a list of window strike solutions. is the company that Hoy used last spring for demonstration tapes.

Let’s get ready for the spring migration and make it safer for the birds.

Helen Pugh
Hoy Audubon Society