Stopping bees swapping hives keeps disease down and productivity up

MUCH GUFFUN has been written in recent years about the risk of honey bees disappearing. They are not—which is hardly surprising, because unlike most other insects they are domesticated animals and their numbers are therefore controlled ultimately by human desire for the honey they produce and the pollination services they provide. Estimates by the Food and Agriculture Organisation suggest that, far from falling, the number of hives in the world is increasing by about 2% a year.This is not to say, however, that beekeepers have had it easy. A decade ago a mysterious phenomenon called colony-collapse disorder, in which worker bees deserted hives for no apparent reason, struck apiarists in Europe and America. More prosaically, crowding brought about by domestication can promote disease. A particular risk is , a parasitic mite that has been spreading through the world’s hives since the 1970s. The mites themselves suck body fat from their hosts. They also carry a virus that affects bees’ development, deforming the insects’ wings.