The Annual 9/11 ‘Tribute in Light’ Really Messes With the Birds

A new study shows that one million birds have been influenced by NYC's annual "Tribute in Light," which memorializes 9/11 victims. Scientists say the study shows the larger impact of light pollution. (Image by Abc36/Wikimedia Commons) For one night every year, 88 Manhattan searchlights beam two columns of light toward the heavens. These “phantom towers,” known as the Tribute in Light, are an annual reminder of the thousands who died in the 2001 terrorist attacks. But these ethereal lights are also a beacon for migrating birds. Like bugs to a streetlight, they’re drawn in from far off paths. The birds — warblers and cuckoos and scarlet tanagers and Baltimore orioles and many more — circle endlessly, expending much needed energy, until they break free of the trance. Sometimes, they die. And in a study published Wednesday in the Proceedings of the National Academy of Sciences, researchers have put a number on the impact. The ornithologists estimate that the Tribute in Light disoriented 1.1 million migrating birds over the seven nights — across seven years — that they conducted their study. But these scientists, who’ve worked with memorial organizers since nearly the beginning, are not calling for the Tribute in Light to be changed in any way. Rather, they’ve used the circumstances as a natural experiment to study how urban light pollution impacts birds. “The unique part of this is that we can see what happens when we shut the lights off,” says lead author Andrew Farnsworth, an ornithologist at Cornell University.