Vanishing honeybees mystify scientists

Go to work, come home. Go to work, come home. Go to work -- and vanish without a trace.

Billions of bees have done just that, leaving the crop fields they
are supposed to pollinate, and scientists are mystified about why.

The phenomenon was first noticed late last year in the United
States, where honeybees are used to pollinate $15 billion worth of
fruits, nuts and other crops annually. Disappearing bees also have been
reported in Europe and Brazil.

Commercial beekeepers would set their bees near a crop field as
usual and come back in two or three weeks to find the hives bereft of
foraging worker bees, with only the queen and the immature insects
remaining. Whatever worker bees survived were often too weak to perform
their tasks.

If the bees were dying of pesticide poisoning or freezing, their
bodies would be expected to lie around the hive. And if they were
absconding because of some threat -- which they have been known to do
-- they wouldn't leave without the queen.

Since about one-third of the U.S. diet depends on pollination and
most of that is performed by honeybees, this constitutes a serious
problem, according to Jeff Pettis of the U.S. Agricultural Research
Service.

"They're the heavy lifters of agriculture," Pettis said of
honeybees. "And the reason they are is they're so mobile and we can
rear them in large numbers and move them to a crop when it's
blooming."  Continued...