Colony collapse disorder (CCD), disorder affecting honeybee colonies that is characterized by sudden colony death, with a lack of healthy adult bees inside the hive. Although the cause is not known, researchers suspect that multiple factors may be involved. The disorder appears to affect the adult bees’ ability to navigate. They leave the hive to find pollen and never return. Honey and pollen are usually present in the hive, and there is often evidence of recent brood rearing. In some cases the queen and a small number of survivor bees may remain in the brood nest. CCD is also characterized by delayed robbing of the honey in the dead colonies by other, healthy bee colonies in the immediate area, as well as slower than normal invasion by common pests, such as wax moths and small hive beetles. The disorder appears to affect only the European honeybee (Apis mellifera).
The unexplained loss of honeybee colonies that came to be known as CCD was first reported in the fall of 2006 by a commercial beekeeper from Pennsylvania, U.S., who was overwintering his colonies in Florida. (Subsequent investigations suggested that beekeepers had experienced unexplained colony losses for at least the previous three years; similar losses had been reported previously as well, including in the late 19th century and in various decades of the 20th century.) By February 2007 several large commercial migratory beekeeping operations in the United States had reported cases of CCD, with some operators suffering the loss of 50–90 percent of their colonies. Many of these larger operations were overwintering their colonies in California, Florida, Oklahoma, and Texas. By late February 2007 some nonmigratory operations located in the mid-Atlantic region and the Pacific Northwest of the United States also had reported the loss of more than 50 percent of their colonies. The absence of dead bees in the affected hives made initial investigations difficult and inconclusive. That same year, other countries, including Canada, Portugal, Italy, Spain, Greece, Germany, Poland, France, and Switzerland, also reported substantial losses of honeybees. From 2006 to 2011 total annual colony losses in the United States averaged around 33 percent; beekeepers cited CCD as the cause of roughly one-third of those losses.
Beekeeping is a critical component of modern agriculture. CCD not only threatens the beekeeping operations that provide pollination service and honey production but also has the potential for crippling the production of the many crops that are dependent on honeybees for pollination. In the United States, beekeepers provide pollination service for more than 90 commercially grown crops, including many fruits and vegetables. The economic value of U.S. crops that benefit from honeybee pollination has been estimated at $15 billion annually. In 2006 the California almond export crop alone was valued at $1.9 billion and required more than one million bee colonies for pollination (out of a total of about 2.6 million colonies in the United States). With the number of available colonies for crop pollination in the country in decline, the beekeeping industry faced a tremendous challenge in meeting the demand for pollination services.