Originally, CCD struck hardest in the U.S., but the condition has begun to turn up in other locales. British beekeeper John Hamer, seen here, tends to his bees at the Blackhorse Apiary Beekeeping Centre in St Johns.

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Vanishing Bees

Honeybees are social creatures, one of the reasons they're ideal pollinators for commercial beekeepers. They're relatively easy to transport and manage, and they aren't too picky about where their nectar comes from, so they can adapt to pollinating many plants.

However, the job of beekeeping is tough. There are several factors that can complicate the rearing of honeybees. For example, mites and fungi can infest a hive and cause health-related problems for the bees. It can be expensive and challenging to provide bees with all the proper nutrition they need, especially as foraging land becomes scarcer.

Bees can also give their beekeeper a nasty shock when they go missing from their hives. Regular attrition rates are always present in hives and usually peak in winter (generally up to about 20 percent is normal), but Colony Collapse Disorder is on a whole other scale [source: Barrionuevo].

According to the USDA Agricultural Research Service, Colony Collapse Disorder may have been present in the U.S. as early as 2002, although it wasn't until 2006 that the numbers hit a fever pitch. Between October and December 2006, U.S. beekeepers saw their hives failing at rates much higher than the normal yearly turnover. Of the affected beekeepers, some 30 to 90 percent of their bees were dying. Between September 2007 and March 2008, U.S. losses were estimated at about 36 percent of managed hives [source: Science Daily].

Colony Collapse Disorder is characterized by the inexplicable absence of the majority of a hive's bees. Sometimes the queen, larvae and a few younger bees are still present, along with the colony's honey and bee bread (a combination of pollen and nectar), but the rest of the community is absent. An empty hive can be hot real estate in the insect world, especially if it's full of honey. But other insects, like moths, beetles and other bees that would typically leap at the chance to become the new tenants of a beehive, avoid CCD colonies for at least a few days. So what's happening to these vanishing bees?

This recent outbreak of CCD is not the first time bees have pulled a disappearing act, but it's the most severe and widespread. First noticed on a large scale in the U.S., cases have since been reported in other parts of the world like Europe. Although Australia has had trouble with CCD, the year 2008 turned out to be normal for beekeepers. CCD could spell disaster for the agriculture industry because of its reliance on honeybees as pollinators. Many industry leaders and researchers are looking into alternatives in the event the worst should happen and bees are no longer viable agricultural pollinators.

So what's making some bees fly off to greener pastures (or, more likely, fly off to die)? That's the million-dollar question that researchers and apiarists (beekeepers) are trying to answer. On the next page, we'll look at some of the possible causes of CCD.