Colony Collapse Disorder (or CCD) is a phenomenon in which worker bees from a beehive or Western honey bee colony abruptly disappear. While such disappearances have occurred throughout the history of apiculture, the term Colony Collapse Disorder was first applied to a drastic rise in the number of disappearances of Western honey bee colonies in North America in late 2006. European beekeepers observed similar phenomena, albeit to a lesser degree.

The cause or causes of the syndrome are not yet fully understood, although many authorities attribute the problem to biotic factors such as Varroa mites and insect diseases (i.e., pathogens including Nosema apis and Israel acute paralysis virus). Other proposed causes include environmental change-related stresses, malnutrition and pesticides (e.g. neonicotinoids such as imidacloprid), and migratory beekeeping.” <wiki>

Note: In the most recent episode of The Simpsons (Season 20, Ep.08), Lisa’s subplot refers to the current world wide disappearance of bees. <DailyGreen>