This sudden and mysterious disappearance of bees seems like a sci-fi horror story. But this is happening NOW, across the US. It is a new and deadly malady named colony collapse disorder, or CCD. This mystery is rapidly joining the list of major threats such as mad cow disease, West Nile virus, SARS and avian flu.

The CCD scenario is this: worker bees fly off in search of pollen and nectar, but their homing instruments, usually good for miles, seem to fail and they vanish. Other bees assigned duties within a hive take over the foraging role, until they, too, disappear. In a few days, the tens of thousands of bees in a healthy colony dwindle to a few hundred and then finally just to the queen and her attendants.

Beekeepers and entomologists are alarmed by the speed and scale of the losses. It's estimated that 25% of the estimated 2.4 million beehives nationwide have been lost to CCD just since last fall.

Absolutely no one yet knows why the bees are disappearing. Some people think it may be pesticides which are causing disorientation for bees. Perhaps genetically modified foods. Even cellphones - perhaps cellphone microwaves are wrecking the bees' radar homing mechanisms. Others think it's a fungus. These are just theories and everyone is still guessing.

This disappearing-bee crisis threatens to wipe out production of crops which are dependent on bees for pollination. Bee pollination is involved in the production of a wide range of fruits, vegetables and forage crops - apples, avocados, cherries, cranberries, cucumbers, melons and sunflowers. The estimated loss is about $ 15B a year.

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