Starting in 2006, commercial migratory beekeepers along the East Coast of the United States began reporting sharp declines in their honey bee colonies. Because of the severity and unusual circumstances of these colony declines, scientists named this phenomenon colony collapse disorder (CCD). Current reports indicate that beekeepers in most states have been affected. Overall, the number of managed honey bee colonies dropped an estimated 35.8% and 31.8% in the winters of 2007/2008 and 2006/2007, respectively. Preliminary loss estimates for the 2008/2009 winter are reported at 28.6%. To date, the precise reasons for colony losses are not yet known. In the United States, bee pollination of agricultural crops is said to account for about one-third of the U.S. diet, and to contribute to the production of a wide range of high-value fruits, vegetables, tree nuts, forage crops, some field crops, and other specialty crops. The monetary value of honey bees as commercial pollinators in the United States is estimated at about $15 billion annually ( Table 1 ). How CCD Differs from Past Bee Colony Losses

Current bee colony losses seem to differ from past losses in that colony losses are occurring mostly because bees are failing to return to the hive (which is largely uncharacteristic of bee behavior); bee colony losses have been rapid; colony losses are occurring in large numbers; and the reason why these losses are occurring remains still largely unknown. As outlined in USDA's 2007-2008 progress report, the available research over the past few years on the numerous possible causes for CCD has led USDA and university researchers to conclude that "no single factor alone is responsible" for CCD. Currently, USDA states, researchers are focusing on three major possibilities: 
1. pesticides that may be having unexpected negative effects on honey bees; 2. a new parasite or pathogen that may be attacking honey bees, such as the parasite Nosema ceranae or viruses; and 3. a combination of existing stresses that may compromise the immune system of bees and disrupt their social system, making colonies more susceptible to disease and collapse. Stresses could include high levels of infection by the V arroa mite; poor nutrition due to apiary overcrowding, pollination of crops with low nutritional value, or pollen or nectar scarcity; exposure to limited or contaminated water supplies; and migratory stress. As outlined in USDA's progress report, prior study of the numerous possible causes for CCD has led researchers to further examine the hypothesis that CCD may be "a syndrome caused by many different factors, working in combination or synergistically." Available USDA Research Funding

Funding for honey bee and CCD research at USDA's ARS has increased, following enactment of the 2008 farm bill ( P.L. 110-246 ) and also FY2009 and FY2010 appropriations ( P.L. 111-8 and P.L. 111-80 , respectively), which, among other things, provide additional funding for research and conservation programs addressing honey bees and pollinators.
Starting in late 2006, commercial migratory beekeepers along the East Coast of the United States began reporting sharp declines in their honey bee colonies. Because of the severity and unusual circumstances of these colony declines, scientists named this phenomenon colony collapse disorder (CCD). Reports indicate that beekeepers in most states have been affected. Overall, the number of managed honey bee colonies dropped an estimated 35.8% and 31.8% in the winters of 2007/2008 and 2006/2007, respectively. Preliminary loss estimates for the 2008/2009 winter are reported at 28.6%. To date, the precise reasons for colony losses are not yet known.
Honey bees are the most economically valuable pollinators of agricultural crops worldwide. Scientists at universities and the U.S. Department of Agriculture (USDA) frequently assert that bee pollination is involved in about one-third of the U.S. diet, and contributes to the production of a wide range of fruits, vegetables, tree nuts, forage crops, some field crops, and other specialty crops. The monetary value of honey bees as commercial pollinators in the United States is estimated at about $15-$20 billion annually.
Honey bee colony losses are not uncommon. However, losses in recent years differ from past situations in that colony losses are occurring mostly because bees are failing to return to the hive (which is largely uncharacteristic of bee behavior); bee colony losses have been rapid; colony losses are occurring in large numbers; and the reason(s) for these losses remains largely unknown.
Based on the available research over the past few years on the numerous possible causes of CCD, USDA concluded in its 2007-2008 progress report (released in June 2009) that "it now seems clear that no single factor alone is responsible for the malady." This has led researchers to further examine the hypothesis that CCD may be "a syndrome caused by many different factors, working in combination or synergistically." Currently, USDA states, researchers are focusing on three major possibilities:
pesticides that may be having unexpected negative effects on honey bees; a new parasite or pathogen that may be attacking honey bees, such as the parasite Nosema ceranae or viruses; and a combination of existing stresses that may compromise the immune system of bees and disrupt their social system, making colonies more susceptible to disease and collapse. Stresses could include high levels of infection by the Varroa mite; poor nutrition due to apiary overcrowding, pollination of crops with low nutritional value, or pollen or nectar scarcity; exposure to limited or contaminated water supplies; and migratory stress.
Funding for honey bee and CCD research at USDA's Agricultural Research Service (ARS) has increased sharply, following both the enactment of the 2008 farm bill (P.L. 110-246) and the FY2009 and FY2010 appropriations process (P.L. 111-8 and P.L. 111-80, respectively). These legislative actions contained additional provisions that would, among other things, provide additional funding for research and conservation programs addressing honey bees and pollinators. Total ARS funding for honey bee and CCD research averaged more than $7.7 million each in FY2007 and FY2008, increasing to $8.3 million in FY2009 and $9.8 million for FY2010.