Abstract

Overview

Night-migratory songbirds rely on a light-dependent magnetic compass, thought to be influenced by the photochemical formation of radical pairs in cryptochrome proteins. This compass helps them orient using the Earth’s magnetic field.

Findings

• Weak radiofrequency (RF) electromagnetic fields have been observed to disrupt bird orientation, a critical diagnostic for understanding the radical pairs’ identities in cryptochrome (Cry) proteins.
• The study tested RF noise at frequency bands 140 to 150 MHz and 235 to 245 MHz on Eurasian blackcaps and found no effect, suggesting operational frequencies for magnetic orientation.
• Significant disruption occurs under 116 MHz, declining sharply above this frequency.

Conclusion

The evidence strengthens the theory that bird orientation is managed via a radical pair mechanism sensitive to specific RF field frequencies, highlighting the potential risks of RF pollution to natural navigation systems in wildlife.