By Susan Milius
When Martin Wikelski and David Wilcove went bird-watching in Cape May, N.J., one fall day in 2004, they were surprised to find that the main spectacle had four wings instead of two. Migrating dragonflies filled the air, flashing iridescent green and blue as they hovered over dunes, perched, then zipped off.
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“They were everywhere,” says Wikelski, who’s a biologist at Princeton University. He and his Princeton colleague Wilcove had come to admire birds that take a break on the long haul up and down the East Coast, but insects on long journeys need rest stops too.