Birds' Magnetic Compass: Can RF Waves Disrupt It?

Did you know that night-migratory songbirds use the Earth's magnetic field to navigate? This is thanks to a special light-dependent magnetic compass sense. Scientists believe this sense works because of certain light-sensitive proteins called cryptochromes in the birds' eyes. Interestingly, weak radiofrequency (RF) waves can confuse these birds. Researchers have been using this fact to understand how the magnetic compass sense works. They predicted that RF waves could disrupt this sense up to a certain frequency. A study on Eurasian blackcaps, a type of songbird, found that RF waves in two specific frequency bands (140 to 150 MHz and 235 to 245 MHz) did not affect their magnetic orientation. This means these birds could still find their way despite the RF waves. Scientists think that RF waves affect the birds' magnetic sense in a certain way, and this effect should be the same up to a frequency of around 116 MHz. Beyond this, the birds' sensitivity to RF waves decreases significantly. Combining this new finding with previous research, it's clear that the magnetic compass of migratory birds works through a process involving light-sensitive proteins. This process is called the radical pair mechanism.