Electromagnetic waves emitted by sources such as the morning radio could be interfering with migratory robins' ability to navigate through their pilot sense.
"Modern-day charlatans will try to exploit this study to claim that cellphone radiation causes damage, but it's not screwing up the robins," geobiologist Joseph Kirschvink of the California Institute of Technology in Pasadena, who was not involved in the study, said, AAAS Science reported. "It's telling them to use a different sense."
Robins tend to migrate using Earth's magnetic field, but they heave other options. The sense shuts down when it could lead them off course, such as when the Earth's geomagnetic field has a fluctuation in strength.
During the spring and autumn robins are so drawn to the direction of migration that they will scratch at the wall facing that direction if kept in captivity. When kept in wooden huts on the University of Oldenburg campus the birds did not exhibit this behavior.
The research team installed aluminum walls and metal rods in the birds' huts to absorb the electromagnetic waves. Once these were installed the robins started exhibiting the behavior once again.
"We added a number of securities to protect ourselves from wishful thinking," neurosensory biologist Henrik Mouritsen of the University of Oldenburg, who led the study, said. "The conditions were repeated with different generations of students, and experiments were blinded on all levels."
The most disorienting frequencies were found to be those emitted by AM radios stations and electronic article surveillance; these waves are 1,000 times less powerful than those emitted by cell phones and 400 times higher than those produced by power lines.
"I just wonder where this strong field originates," retired zoologist Roswitha Wiltschko, who co-discovered the avian magnetic compass with her husband Wolfgang but was not involved in the study said, AAAS Science reported. "We were doing these experiments in the central district of Frankfurt, a major city, and we never had problems with magnetic fields disrupting the orientation of our birds." Wiltschko feels the study is "really well done" but thinks more research is needed before claiming that this is a general occurrence.
