For birds, glass windows can be deadly. Reflecting foliage or sky, windows often appear as inviting spaces to fly into. With the sheer number of windows in our world, collisions pose a significant threat to bird populations. Studies estimate that up to a billion birds die annually in the U.S. alone from window strikes. This article explores why birds collide with windows and provides practical solutions to prevent these often fatal accidents.
american goldfinch killed by window strike
Fortunately, you can significantly reduce the risk to birds around your home. Simple and effective remedies can make your windows safer for our feathered friends. Organizations like the American Bird Conservancy and the Fatal Light Awareness Program (FLAP) offer valuable resources and information on preventing bird collisions.
Understanding Why Bird Window Strikes Occur
imprint of dove on plate glass window
Birds collide with windows for various reasons, primarily during daylight and nighttime hours. During the day, reflections of trees, shrubs, or the sky in windows confuse birds, making them think they are flying into open space. They might also see through the glass to indoor plants or vegetation on the other side, further contributing to the illusion.
At night, the problem shifts to artificial light. Nocturnal migrants, including many songbird species, are drawn to lighted windows, especially during low visibility conditions like fog or overcast skies. Disoriented by the light, they may circle the illuminated area, increasing the risk of collision with each other or the building. Furthermore, birds drawn off course by city lights may roost nearby, making them vulnerable to daytime window reflections the following day. Organizations like BirdCast and FLAP provide in-depth information on the dangers of artificial light at night for migratory birds.
Effective Methods to Prevent Bird Strikes
reflection of foliage in window – hazard to birds
Identifying high-risk windows is the first step. Large picture windows, windows at right angles, and those near feeders are particularly dangerous. Observe your windows from a bird’s perspective to identify reflective surfaces or see-through views that could lure birds.
Solutions for Existing Windows
Several effective treatments can be applied to existing windows to deter bird strikes. For smaller birds, markings should be spaced approximately 2 inches apart, while larger visual deterrents like Acopian BirdSavers can be spaced 4 inches apart. Crucially, all treatments should be applied to the outside of the window. Some effective options include:
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Tempera Paint or Soap: Applying a grid pattern or creative designs with tempera paint or soap is a cost-effective and durable solution.
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Decals and Stickers: Decals, stickers, or even sticky notes can be effective, but they must be applied densely, covering a significant portion of the glass surface. Hawk silhouettes are generally ineffective.
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Dot Patterns and Tape: Specialized tapes with pre-spaced dot patterns offer a convenient and long-lasting solution. Products like those from Feather Friendly are specifically designed for this purpose.
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Acopian BirdSavers: These closely spaced cords, also known as “zen curtains,” hang vertically over windows, providing a highly effective visual barrier. They are aesthetically pleasing and easy to install.
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Screens and Netting: Installing tight-fitting screens or netting on the outside of windows creates a physical barrier that prevents birds from reaching the glass.
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One-Way Transparent Film: Films like Collidescape allow visibility from the inside while making the window appear opaque from the outside, effectively deterring birds.
Strategies for New Construction and Renovations
Incorporating bird-safe strategies during new construction or renovations offers a proactive approach. These include:
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Exterior Shutters or Sun Shades: Installing external shutters or awnings can significantly reduce reflections and make windows less attractive to birds.
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Exterior Screens: Opt for windows with screens installed on the outside of the glass.
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Interior Vertical Blinds: Keeping vertical blinds half-closed can disrupt reflections and make the window less appealing to birds.
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Strategic Window Placement: Consider the placement of windows to minimize reflections of sky and vegetation.
Conclusion
By understanding why birds collide with windows and implementing practical solutions, we can significantly reduce the number of bird strikes. Whether you choose simple DIY methods or invest in specialized products, making your windows bird-safe is a crucial step in protecting bird populations. Every effort, no matter how small, contributes to creating a safer environment for birds.
