I'm certain you are all aware that growers of fruits and vegetables are seriously worried about the heretofore unexplained absence of honeybees upon which the farmers rely to pollinate their plants. So far, no masses of dead bees have been identified.
I've come upon the answer, though, and the problem is only temporary. It appears the bees have been working so hard for so long that they decided they needed a period for the entire population to rest and recover from their efforts.
They've all convened at a single location for a few weeks. This is the first known example of global swarming.