Reduce Window Threats

Some home windows can be deadly for birds because glass is invisible to them. Up to 1 BILLION birds die every year after colliding with U.S. buildings, nearly half at our homes. Reflections of trees, plants and sky — or such habitat seen through a window on the other side — can be a problem. Read more.

The good news is that typically only a few windows in our home are problems for birds. Try fixing one window — where you’ve heard birds hit before, windows next to feeders or bird baths, or picture windows or sliding glass doors. Find easy, inexpensive and effective options below.

Easy options for making windows safer for birds

Man installs an external insect screen

Add an external insect screen or bird screen

Tests by researchers have shown that installing ordinary removable insect screens on the outside of the window is effective in preventing bird collisions. Full-window screens are best, according to the American Bird Conservancy Glass Collision Program.

The Bird Screen Company sells a specialized removable bird screen that can be attached to the outside of windows with suction cups.

The reflection on a patio door is broken up by a grid of light colored dots

Apply a commercial film or markers to outside of windows

Visible patterns applied to the outside of windows following spacing guidelines can prevent collisions and be effective and unobtrusive. We’ve heard good things about Feather Friendly, Bird Divert and ABC BirdTape and all three have been tested and proven effective by the American Bird Conservancy’s Glass Collision Program.

A curtain of dark parachute cord hangs in front of a window

Hang an Acopian BirdSavers curtain on the outside of windows

If you don’t want to apply something directly on the outside of your window, try installing a curtain of parachute cord to hang on the outside of it. These Acopian BirdSavers, also known as “zen wind curtains” are easy, long-lasting, and very effective.

  • Get 15% off customized Acopian BirdSavers from April 1 to May 31, 2024. Enter the Coupon code "SOS Wisconsin" at check out.

Apply decals or use non-toxic Tempura paint or oil-based markers to add lines or other designs to the outside of windows, following guidelines from American Bird Conservancy’s Glass Collision Program :

  • Space lines or dots 2 inches apart so hummingbirds and other very small birds don’t try to maneuver through. Lines should be at least 1/8 inch thick, dots 1/4-inch in diameter.

  • Use decals that are at least 1/4 inch in diameter and spaced 2 to 4 inches apart.

  • Try these DIY decals with instructions and printable bird decal stencils from New York Audubon: https://ny.audubon.org/conservation/how-create-window-decals-prevent-bird-collisions

  • If the window reflections are dark, make the lines, patterns or decals light-colored. For glass railings outside or if the window is reflecting sky, dark colors are best.

Paint decorations or place decals on outside of windows

How to handle hard-to-reach windows

Local contractors or window washers may be able to help add treatments to windows you can’t reach from the ground. Another option: The Home Depot provides access to independent licensed, insured contractors.

Doing something is better than doing nothing. If you can’t put a treatment on the outside, turn window blinds at an angle so it creates a bar for birds to see. These might be hidden by reflections and not work, but it could make a difference. Or, add decals or some other solution to the inside of the problem window, following spacing, thickness and color recommendations above.

Shield lights and turn them off at night during migration

Lights from our homes can pose a problem for migrating birds at night. The lights contribute to a “glow” that may signal to birds its time to stop and take a rest when it’s better for them to travel on to more rural areas where there’s a lower density of windows, cars, cats and other threats.

Shield lights or direct the light down, and turn off lights from midnight until it’s light in the morning during spring and fall migration will help birds survive and reach nesting sites. Learn more.

Want to get involved in more bird-collision prevention efforts?

Several Wisconsin organizations work on a broader scale and with bigger buildings to reduce bird collisions. Learn more about these efforts and volunteer!

Madison Audubon’s Bird Collision Corps volunteers conduct weekly surveys for dead or stunned birds around their assigned buildings during spring and fall migrations. Learn more and volunteer. 

Aldo Leopold Audubon’s Safe Passage program with the city of Stevens Point enlists businesses in taking actions during peak migration periods to prevent bird collisions with their buildings.

Wisconsin Humane Society’s Night Guardians for Songbirds recruits volunteers to patrol parts of downtown Milwaukee in early morning during peak migration to collect and rescue injured or dead songbirds.

Photo caption: Songbirds killed after colliding with buildings in Madison monitored during migration by Madison Audubon’s Bird Collision Corps. Credit: Madison Audubon