The Blackburnian Warbler is a small songbird with a flame-orange head. The striking bird largely nests in the far Northeastern United States, around the Great Lakes, and into Canada, but when it’s time to head south, this neotropical migrant, which weighs less than an ounce, wings it all the way to the Andes Mountain in South America. Blackburnians have been making this trek for thousands of years, but over the past century, the odyssey has become increasingly treacherous. Now tall towers of glass and steel protrude into the sky; houses, roads, and concrete cover the once virgin landscape; and at night, the world can look like a neverending Lite Brite. All of these changes, in one way or another, pose deadly dangers to the Blackburnian and millions of other migrating songbirds every year, putting an abrupt end to their heroic journeys. It doesn't have to be this way. Though we might not be able to reverse human development, we can be proactive about preventing bird...