Poster

1. The disruption of magnetic compass orientation in night-migratory songbirds by radiofrequency magnetic fields is mediated by a

separate
sensory system
Nikita Chernetsov1,2, Julia Bojarinova1, Dmitriy Sannikov1, Roman Cherbunin1,2, Alex Pakhomov3,
Aleksandra Fedorishcheva4, Kirill Kavokin1,2
1 Zoological Institute RAS 2 St. Petersburg State University 3 Biological Station Rybachy
4 Lomonosov Moscow State University
Magnetic compass in migratory birds is disrupted by oscillating magnetic fields (OMFs) in the
radiofrequency range. We subjected pied flycatchers to OMFs with carrier frequencies of 1.41 and 1.5
MHz with the square-wave amplitude modulation at 500 Hz.
Orientation in the natural magnetic field (NMF), in 47 nT sinusoidal OMF at 1.41 MHz and in
square wave modulated (SWM) OMF (autumn)
Orientation in NMF, in 47 nT sinusoidal OMF at 1.5 MHz and in SWM OMF (autumn)
Orientation in NMF, in 30 nT sinusoidal OMF at 1.5 MHz and in SWM OMF, (spring)
The modulated OMF, having twice less mean power than that without modulation, caused disorientation
at a lower amplitude of the carrier wave than the unmodulated OMF. The prediction of the
photochemical theory is exactly the opposite, therefore we conclude that the effect of OMFs on magnetic
orientation of birds is not related to the decoherence of electron spins in cryptochrome they would cause.
Instead, we suggest that OMFs are perceived by a separate sensory system, most likely based on
electromagnetic induction.
Supported by Russian Science Foundation grant 24-14-00085