Audubon Magazine: That sounds awfully high to BirdCast researcher and Colorado State University ornithologist Kyle Horton. A mass-mortality event like the one in the video typically requires a confluence of factors, he says: a source of light pollution, winds that favor migration, and fog or a low cloud ceiling. “It’s probably not happening night after night,” since that combination occurs only occasionally, Horton says. “But I still think it’s not just something to write off, either. Dimming the lights on the boat would probably be the obvious solution, and it seems like an easy fix.”

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