Winged Migration Grows Up
Scientists used to rely on metal bands on birds’ legs to find out how they got from here to there. Now, they can glue tiny radio transmitters to their shoulders and follow them in real time. What happened when Princeton scientists hijacked 30 white-crowned sparrows and took them from Seattle to New Jersey? Age has its advantages, it turns out. Read about it on PhysOrg and EurekAlert.
The adults soon realized they were 3,000 miles off course, and adjusted their bearing to fly southwest toward their winter quarters in Mexico. The juveniles, who had never flown home before, flew directly south. This indicates that the chicks are born with an innate compass that works OK the first time, but experience helps the adults develop a global map that can make corrections.
The white-crowned sparrow usually flies solo at night. Upon release, all the birds seemed a little disoriented at first. After a couple of days the adults converged on the correct orientation.
The article did not say if the scientists were able to bring the lost youngsters home, because the devices apparently did not have receivers to which they could send commercials, like “Fly Southwest.” Hopefully they will enjoy Florida.
Ongoing research into bird migration shows that it is a multi-faceted skill that employs magnetic fields, celestial navigation, smell, visual landmarks, and more. How the chicks of the Pacific Golden Plover fly from Alaska to the tiny specks of the Hawaiian islands, alone, across open ocean, using only an innate compass, is one of those wonders of nature that defies evolution. Time to enjoy Winged Migration again: a film whose photographic excellence and amazing content should adorn every home theater. Looks great in HDTV.