Noise From Our Electronics 'Disrupts Bird Navigation'
Interference from electronics and AM radio signals can disrupt the internal magnetic compasses of migratory birds, according to a new study.
Previously, experiments have shown that migratory birds can orient themselves on migration paths using internal compasses guided by Earth's magnetic field. However, not much evidence was available that established the fact that electromagnetic radiation created by humans affects the process.
The study raises the possibility that cities might have a significant effect on bird migration effects.
"At first, I was highly sceptical that this could be the explanation," Prof Henrik Mouritsen, from the University of Oldenburg in Germany, who carried out the research, told BBC.
"But if you have seemingly unlikely effects then the proof needs to be much stronger - and that is why we have done so many experiments over seven years and it has taken a long time before we were confident to come out with this to the public."
Some birds perform remarkable feats of navigation, migrating half way around the world, wrote BBC.
Prof Mouritsen said he stumbled across the finding that low frequency waves could be interfering with this by accident while he was studying European robins.
"The basic experiment we do in bird navigation research is that we put birds into an orientation cage," he explained.
"They are so eager to migrate, that they will jump in the direction in which they want to fly, and if you turn a static magnetic field in the horizontal plane they will start to jump in a different direction.That experiment has worked for more than 40 years in a number of locations. But here in Oldenburg, we couldn't get that basic experiment to work until one day we got the idea to screen these huts on the inside with aluminum plates so the electromagnetic noise was reduced about 100 times.And suddenly the birds started to orientate."
The study has been published in the journal Nature.