Bees and electromagnetic waves
The possibility of electromagnetic pollution is controversial and not much investigated. This hypothesis is suggested by some beekeepers but is not yet been proven or refuted by probative studies.
We know that bees make use of magnetite crystals present in their abdomen, to capture the earth's magnetic field in order to get their bearings in space. It is believed that bees are sensitive to the earth's magnetic fields, but it remains to be proven that these waves are a cause or not of the decline of bees as observed in the recent years.
According to the research conducted in the 80s, bees are able to detect weak variations of the magnetic field, but this sensitivity decrease as the frequency of this magnetic field increases (above 60 Hz). However, electromagnetic waves emitted by wireless devices such as mobile phones, use high frequencies (MHz or GHz). According to this research, the bees would therefore not be affected by these waves.
Doubts resurfaced with the publication of various works highlighting the sensitivity of bees to electromagnetic fields. Researchers at the University of Koblenz have studied the effect of electromagnetic fields on bees. These scientists subjected some hives to radiations from wireless phone stations operating under DECT standards. According to this study, the acquired weight of the cell frames of irradiated colonies is 20% lower than that of non-irradiated colonies. Moreover, the number of irradiated bees returning to the hives is much lower than that of non-irradiated bees. Now we know that if the bees do not return to the hive, they die. These results should be taken with caution since the methodology used in this work has been severely criticised.
Large-scale studies still need to be conducted. At present, no such study exists in Belgium.