The researchers equipped 14 wood thrushes and 20 purple martins with tiny geolocators—the first tracking devices small and light enough for songbirds to carry—to map their round trip between North America and the tropics with unprecedented accuracy.
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Stutchbury and her team released their birds in summer 2007 and snagged returnees the next spring, along with data on their routes and migration rates.

The birds' travel speeds astounded them. All flew two to six times faster during their spring return journey than in fall. One female purple martin dashed back north in 13 days at a speed of about 358 miles (577 kilometers) a day, shattering previous estimates for songbirds of 93 miles (150 kilometers) a day.

"Maybe this is some kind of super-bird, but still I was really impressed that any bird can do this," Stutchbury said. "These birds are traveling really fast and breaking all the rules." ...