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Cool new research indicates that songbirds can really turn on the afterburners while on migration, and cover much more ground in a night than previously thought.

York University’s Bridget Stutchbury and colleagues attached GPS monitoring backpacks to 34 Wood Thrushes and Purple Martins during the fall of 2007, and retrieved them from 7 of those individuals (5 thrushes and 2 martins) during the summer of 2008. With this new technology, they could analyze such things as the length of stay in a particular migratory stopover location, speed of travel between stops, and the specific wintering location of birds from a specific breeding location. The latter issue, migratory connectivity, has been especially difficult to demonstrate.

The going wisdom had been that migratory songbirds could cover about 100 miles in a night, but Stutchbury’s data indicated that the birds were actually covering about 300 miles. This means that the birds were flying faster than expected. It’s unclear to me, however, if the birds were literally flying 3X faster than previous (wind tunnel?) estimates or if the extra speed came from the behavioral choice of flying only when strong tail winds could provide a powerful push.

No matter how they did it, however, it is clear that some of their trips were fast. One Purple Martin made the trek from Brazil to Pennsylvania in 13 days! Other cool findings include that fall migration was protracted (with individuals spending 2-4 weeks in stopover locations) relative to spring migration.

It’s all cool, and you can learn more here: http://www.sciencedaily.com/releases/2009/02/090212141152.htm