When wood thrushes arrive in northern Mississippi on their spring migration and begin to serenade my neighborhood with their ethereal, harmonized song, it’s one of the great joys of the season. It’s also a minor miracle. These small creatures have just flown more than 1,850 miles (3,000 kilometers), all the way from Central America.

Other birds undertake even longer journeys — the Swainson’s thrush, for example, nests as far north as the boreal forests of Alaska and spends the nonbreeding season in northern South America, traveling up to 5,600 miles (9,000 kilometers) each way.

These stunning feats of travel are awe-inspiring, making it that much more tragic when they are cut short by a deadly collision with a glass window.

This happens with alarming regularity. Two recent scientific studies estimate that more than 1 billion birds – and as many as 5.19 billion – die from collisions with sheet glass each year in the United States alone, sometimes immediately but often from their injuries.

In fact, window collisions are now considered the top human cause of bird deaths. Due to window collisions and other causes, bird populations across North America have declined more than 29% from their 1970 levels, likely with major consequences for the world’s ecosystems.

These collisions occur on every type of building, from homes to skyscrapers. At the University of Mississippi campus, where I teach and conduct research as

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