Tiny Bird Backpacks Reveal the Secrets of Songbird Migration

The songbirds that live in the backyards and parks of the northeast United States have just earned a little more respect. Researchers strapped cutting-edge geolocator devises to the backs of purple martins and wood thrushes to track their migrations, and found that the diminutive warblers can fly more than 300 miles each day, tripling previous estimates. But researchers say the biggest achievement was proving that the new technology works, which lays the groundwork for future studies of small birds.