Sense
Magnetoception (or magnetoreception) is the ability to detect the direction one is facing based on the Earth's magnetic field. Directional awareness is most commonly observed in birds, which rely on their magnetic sense to navigate during migration. It has also been observed in insects such as bees. Cattle make use of magnetoception to align themselves in a north-south direction. Magnetotactic bacteria build miniature magnets inside themselves and use them to determine their orientation relative to the Earth's magnetic field.
Magnetoreception
In similar fashion, European ("Bufo bufo") and Natterjack ("Epidalea calamita)" toads appear to rely, at least somewhat, on magnetic information for certain orienting behaviours. These species of anurans are known to rely on vision and olfaction when locating and migrating to breeding sites, but it seems magnetic fields may also play a role. When randomly displaced from their breeding sites, these toads remain well-oriented, and are capable of navigating their way back, even when displaced by more than 150 meters. However, when this displacement is accompanied by the experimental attachment of small magnetic bars, toads fail to relocate breeding sites. Considering experimental attachment of non-magnetized bars of equal size and weight does not affect relocation, it seems that magnetism is responsible for the observed disorientation of these toads. Therefore, researchers have concluded that orientation toward breeding sites in these anurans is influenced by magnetic field information.