Mystery Ailment Killing Bees

Now this is a real mystery to be solved. What is killing all those bees?

Reports of unusual colony deaths have come from at least 22 states.
Some affected commercial beekeepers — who often keep thousands of colonies —
have reported losing more than 50 percent of their bees. A colony can have
roughly 20,000 bees in the winter, and up to 60,000 in the summer.

And here are the clues that they have assembled so far:

• Although the bodies of dead bees often are littered around a hive, sometimes carried out of the hive by worker bees, no bee remains are typically found around colonies struck by the mystery ailment. Scientists assume these bees have flown away from the hive before dying.

• From the outside, a stricken colony may appear normal, with bees leaving and entering. But when beekeepers look inside the hive box, they find few mature bees taking care of the younger, developing bees.

• Normally, a weakened bee colony would be immediately overrun by bees from other colonies or by pests going after the hive's honey. That's not the case with the stricken colonies, which might not be touched for at least two weeks, said Diana Cox-Foster, a Penn State entomology professor investigating the problem.