Colony Collapse Disorder

Colony collapse disorder (CCD) is the phenomenon that occurs when the majority of worker bees in a colony disappear and leave behind a queen, plenty of food and a few nurse bees to care for the remaining immature bees and the queen. While such disappearances have occurred throughout the history of apiculture, and were known by various names (disappearing disease, spring dwindle, May disease, autumn collapse, and fall dwindle disease), the syndrome was renamed colony collapse disorder in late 2006 in conjunction with a drastic rise in the number of disappearances of western honey bee (Apis mellifera) colonies in North America. European beekeepers observed similar phenomena in Belgium, France, the Netherlands, Greece, Italy, Portugal, and Spain, Switzerland and Germany, albeit to a lesser degree, and the Northern Ireland Assembly received reports of a decline greater than 50%.

Colony collapse disorder causes significant economic losses because many agricultural crops (although no staple foods) worldwide are pollinated by western honey bees. According to the Agriculture and Consumer Protection Department of the Food and Agriculture Organization of the United Nations, the worth of global crops with honey bee's pollination was estimated at close to $200 billion in 2005. Shortages of bees in the US have increased the cost to farmers renting them for pollination services by up to 20%.

In the six years leading up to 2013, more than 10 million beehives were lost, often to CCD, nearly twice the normal rate of loss. To put this in perspective, according to U.N. FAO data, the world's beehive stock rose from around 50 million in 1961 to around 83 million in 2014, which is about 1.3% average annual growth. Average annual growth has accelerated to 1.9% since 2009.

Several possible causes for CCD have been proposed, but no single proposal has gained widespread acceptance among the scientific community. Suggested causes include: infections with Varroa and Acarapis mites; malnutrition; various pathogens; genetic factors; immunodeficiencies; loss of habitat; changing beekeeping practices; or a combination of factors. A large amount of speculation has surrounded a family of pesticides called neonicotinoids as having caused CCD.

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