Every spring, one of the most extraordinary wildlife events on the continent unfolds across North America.

Between mid-March and mid-May, billions of birds migrate north, traveling thousands of miles to reach their breeding grounds. Warblers, thrushes, hummingbirds, raptors, and countless other species move across cities, suburbs, forests, and farmland in a massive seasonal movement.

But during this journey, birds face a growing and often invisible danger: glass or other reflective surfaces.

Why Migration Is the Most Dangerous Time for Birds

During migration, birds are navigating unfamiliar environments. Many travel overnight, resting and feeding during the day in places they have never encountered before.

This creates a perfect storm for window collisions.

Research shows that up to 1 billion birds die each year in the United States from window strikes, making it one of the leading human-caused threats to bird populations.

During migration season, the risk becomes even greater:

• Collision risk increases 3–4× as birds move through new territories
• Peak activity occurs from mid-April through mid-May
• Birds are drawn to reflections of sky, trees, and open habitat in glass

To a bird, a window often looks like clear air or open sky. They simply don’t recognize it as a barrier.

Why Birds Hit Windows

Glass presents two visual illusions to birds:

1. Reflections of sky or vegetation make windows appear like safe flight paths.
2. Transparent glass makes birds believe they can fly straight through a building.

Because birds rely primarily on vision to navigate, these illusions can be fatal.

The Good News: Prevention Is Simple and Effective

The encouraging part is that window collisions are highly preventable.

Birds can see ultraviolet light, something humans cannot. By applying materials that reflect UV, we can make glass visible to birds without obstructing the view for humans.

UV bird-safe decals create a visual signal that tells birds: there is a barrier here.

The result:

• Birds recognize the window and avoid it
• People still enjoy a clear view outside
• Collisions drop dramatically

A Small Action That Saves Lives

Protecting birds during migration doesn’t require major changes to your home or building.

Adding properly spaced window markers can dramatically reduce collisions and help birds safely continue their journey north.

If more homes and buildings take this simple step during migration season, we can prevent millions of unnecessary bird deaths each year.

Migration Is Happening Right Now

From mid-March through mid-May, the skies above North America are filled with traveling birds.

With just a few small changes to our windows, we can make that journey safer.

Because every bird that avoids a window strike gets to continue the incredible migration that has been happening for thousands of years.

And that’s something worth protecting.