Why Do Birds Collide with Glass?

Birds do not recognize glass as a solid barrier. Instead, they may see reflections of trees, sky, clouds, and vegetation and perceive the reflection as a place they can fly. Birds may also see through transparent glass to vegetation or open space on the other side and attempt to fly through it.

Windows near trees, gardens, native landscaping, bird feeders, and other bird habitat can be particularly problematic. Glass corners, large picture windows, and other areas where birds can see through a building or structure can also create collision hazards.

Bird-window collisions can occur throughout the year, but they are especially important to address during spring and fall migration, when large numbers of birds move through Central Texas.

How Can You Make Your Windows Safer?

Effective treatments make the glass visible to birds or reduce the reflections that cause birds to fly toward windows.

• Treat the outside of the glass. Exterior treatments interrupt reflections before a bird reaches the window and are generally more effective than treatments placed inside.
• Use closely spaced patterns. Decals, dots, stripes, tape, or other visual markers should be placed across the window rather than using only one or two decals on a large pane of glass.
• Install exterior screens. Window screens can make glass more visible while also providing a physical buffer if a bird flies toward the window.
• Use bird-friendly window film or other products. A variety of films, patterns, and other treatments are available specifically to reduce bird collisions.
• Pay attention to problem windows. If you find a stunned or dead bird near a particular window, consider treating that glass even if collisions have not been observed elsewhere.
• Consider bird-friendly glass when renovating. When replacing windows or designing new buildings, consider glass or exterior treatments designed to reduce bird collisions.

These same approaches can be used at homes, offices, businesses, and other buildings.

Free Window Decals Available

The City of Sunset Valley provides free bird-window decals to residents to help make windows more visible to birds.

Residents can stop by the Sunset Valley Public Works Department to pick up free decals for try at their homes.

Small Changes Can Make a Difference

Sunset Valley's parks, neighborhoods, and more than 270 acres of greenspace provide habitat for resident and migratory birds. Making windows safer helps complement the City's efforts to protect and restore the habitat these birds depend upon.

By identifying problem windows and adding appropriate exterior treatments, residents and businesses can help reduce preventable bird collisions and make Sunset Valley a safer community for birds.