Save the Birds

Windows kill an enormous number of birds each year, and homes are part of the problem. Studies put the U.S. toll at well over a billion birds a year, and researchers say low-rise buildings—including houses one to three stories tall—account for a large share of collisions, more than skyscrapers do. Birds don't perceive glass as a barrier, and even clear glass acts like a mirror in daylight, reflecting sky, trees, or landscaping in ways that confuse birds into flying straight at it.

Fixes exist for homeowners who want to reduce strikes at their own windows. Patterned window film, decals, or dot-and-dash products applied to the outside of glass can help birds recognize it as solid, as long as the pattern is spaced closely enough (roughly a 2-by-2-inch grid) and covers the full pane rather than a few scattered stickers. Products like Feather Friendly and Solyx window films are examples used on buildings of all sizes. Outdoor lighting also matters: turning off or dimming exterior lights during spring and fall migration, especially near peak migration dates for your area (available at birdcast.info), can reduce the chance of birds getting disoriented near your house.

Beyond individual homes, cities including New York, Washington D.C., and San Francisco now require bird-friendly glass on new construction, and free tools such as FLAP Canada's BirdSafe DIY assessment let anyone, including homeowners, evaluate how risky their own building's windows and surroundings might be for birds.