Huge numbers of honeybees began disappearing throughout North America in the winter of 2006. Beekeepers opening their hives expecting to find thousands of bees humming, buzzing and working instead found them barren.

The U.S. Department of Agriculture dubbed the devastating enigma Colony Collapse Disorder.

Experts discussed possible causes of CCD at a 2012 National Stakeholders Conference on honeybee health, finding that parasites, diseases and insecticides all contribute to deaths, and that an increase in genetic diversity is needed.

The number of honeybee colonies had been steadily declining prior to 2006 as well. According to the USDA, in the 1940s there was an estimated 5 million colonies. Today there are only 2.5 million.

More Information

Fact box

In winter 2006, beekeepers across the country reported that 30 to 90 percent of their hives had been lost.

In general, a majority of the hives are lost during the winter. From October 2012 to April 2013, the USDA reported that the national average of hives lost was 31.1 percent.

The life of a honeybee is not easy. The factors behind CCD include the presence of the verroa destructor, a parasitic mite that feasts on the hemolymph (blood, basically, in insects) and kills bee pupae, (the life stage prior to adulthood); the host of chemicals used in weed killers and pesticides that can kill bees or cause them to lose their sense of direction, preventing them from returning to the hive; and changes to bees' natural environment.

The cost to humans is significant. American agriculture relies heavily on honeybees. Honeybees are responsible for the pollination responsible for an estimated one-third of the all food and beverages in the country, according to the USDA. Bees pollinate many of the crops consumed and exported in the United States.

In Connecticut, crops pollinated by bees constitute a $70-million industry, according to the Mark Creighton, the state's apiary inspector.

"There is an important link between the health of American agriculture and the health of our honeybees for our county's long-term agricultural productivity," said Kathleen Merrigan, the agriculture deputy secretary, in a May USDA press release.

Agriculture, made up of the fruits and vegetables grown on local farms, as a whole in Connecticut is a $3.5 billion industry. Some of the crops that are grown in Connecticut include apples, corn, squash, strawberries, asparagus, broccoli, peaches, garlic and more.

mspicer@bcnnew.com; 203-330-6583; @Meg_DarienNews

twoods@bcnnew.com; 203-330-6582; @Woods_NCNews