GPS the robin? Scientists have known for decades that migratory birds rely on the Earth's magnetic field to "adjust" their internal navigation tools that allow them to travel even thousands of kilometers in the right direction.
Devices we use every day produce noise – electromagnetic noise that is not perceived by our ears. But even the electromagnetic hum of computers or AM radio signals may be enough to throw off the internal GPS of migrating birds, a new study reveals.
Scientists have known for decades that migratory birds rely on the Earth's magnetic field to "tune" their internal navigation tools that allow them to travel thousands of kilometers in the right direction. But the new study shows for the first time how humans' reliance on devices affects this internal compass, disorienting the birds.
Henrik Mauritsen of the University of Oldenburg came to this conclusion almost by accident. Based in the Danish countryside, the researcher had been studying the behavior of European robins for years. Every year at the same time, his captive birds turned their bodies in the direction they would fly if they were free. When Mauritsen moved from the countryside to the city of Oldenburg, the robins stopped “looking” in the right direction.
Experiments with changes in food, lighting, cages, etc. did not bring any results. Until a colleague of the researcher suggested that he cover the birds' wooden "house" with aluminum plates. Indeed, the robins returned to their old habits and Mauritsen began to notice that the plates acted as a sound shield from the electromagnetic noise of the city's devices, the "electrosmog", as he calls it.
"We found a very clear and repeatable effect of electromagnetic noise generated by electrical equipment that prevents a bird – in this case the European robin – from using its magnetic compass," the biologist explained to the Washington Post.
But where exactly does this "electric fog" that disorients birds come from? Researchers are not entirely sure, although so far they have ruled out cell phone signals or wi-fi and suspect AM signals and electromagnetic fields from computers, printers, and even refrigerators.
