Despite the Doctor's supposition (Doctor Who, The Stolen Earth) that the bees were led off planet by wavelengths in the Tandocca Scale, it seems the answer is more terrestrial. A new study by the Swiss Federal Institute of Technology reports that honeybees are "fatally confused by the electromagnetic signals coming out of cellphones."
The theory here is that the magnetic fields emitted by cellphones interfere with the bees ability to navigate and communicate. This is picked up by a pigment in the bees called cryptochrome. In June of 2010, researchers in India at Panjab University in Chandigarh put cellphones next to bee hives and activated them for 15 minutes a day. In three months, the bees stopped producing honey and egg production by the queen dropped in half.
I can remember a few days in the summer of 2010 when I was driving on route 206 in New Jersey and there were miles of road with swarms of bees buzzing about the cars. It was so unusual and the swarms so dense that a local radio station reported it with no explanation. It seems likely now, that the talking and texting (shame on those texting), of passing motorists may have been the cause.
It's no sercret that bees are important to our ecosystem: they pollinate a good majority of the world's crops. The economic impact to farmers alone is estimated to be about $12 billion in the U.S. alone. The long-term ecological forecast would only be worse.
Andrew Goldsworthy, a biologist from the U.K.'s Imperial College in London has studied this effect for the past few years. He suggests a change of phone frequencies would keep the bees from being confused: "It's possible to modify the signal coming from the phones and the base station in such a way that it doesn't produce the frequencies that disturb the cryptochrome molecules."
Let's hope the worlds cellular carriers are at least looking into possible frequency changes.