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Geolocators Track Migrating Songbirds

New technology reveals fascinating information
© Kira Delmore and Darren Irwin, UBC View Large

With many migratory songbirds in North America declining at an alarming rate, it’s important to map their travels – and learn what they require for food and shelter.

Until recently, it was difficult to monitor the precise journey of migratory birds. Thanks to the development of geolocators like the one on this Swainson’s Thrush, scientists can now collect data about migratory patterns that will help us protect critical bird habitats, including nesting grounds, wintering grounds, and migratory stopovers.

Full Transcript



Tracking Long-Distance Songbird Migration Using Geolocators

Written by Todd Peterson

This is BirdNote.

[Song of Wood Thrush]

With many migratory songbirds in North America declining at an alarming rate, it’s ever more important to map their travels – to learn what they require for food and shelter, when and where. But until recently it’s been impossible to monitor the precise journey of a bird such as this Wood Thrush. 

[Song of Wood Thrush]

Now we have tiny, light-weight geolocators. When attached to songbirds, these devices record light levels at sunrise and sunset, marking the birds’ exact location. When scientists affixed them to Wood Thrushes and Purple Martins in Pennsylvania, the next spring the returning birds provided new and fascinating information.

[Song of Purple Martin]  

The geolocators showed that during fall migration the songbirds rest and feed at specific stopover points in the Southeastern U.S. and the Yucatan Peninsula. And in the case of the Wood Thrushes, they winter in a narrow band of habitat in Honduras and Nicaragua.  

The geolocators also documented that spring migration is much more rapid than previously thought.  One female Purple Martin flew [the 4,660 miles] from the Amazon Basin to northern Pennsylvania in 13 days, with nine days on the wing – an average of over 350 miles a day.  [It turns out that spring migration is two to six times faster than in the fall.] 

Whether spring or fall, we’re learning the location of habitats that need to be protected, to help the birds survive.  

[Song of Wood Thrush]

For BirdNote, I’m Michael Stein.


Bird sounds provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York.  Song of the Wood Thrush [40807] recorded by G.F. Budney; Song of Purple Martin [109261] G.A. Keller; flock of Purple Martins [8091] by C.A. Sutherland.  Ambient midway drawn from [12084] C. Duncan.

BirdNote’s theme music was composed and played by Nancy Rumbel and John Kessler.

Producer: John Kessler

Executive Producer: Chris Peterson

© 2013 Tune In to    July 2013   Narrator: Michael Stein

ID#  geolocator-02-2013-07-22             geolocator-02

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