"The phenomenon now being witnessed across the United States has been dubbed ?colony collapse disorder,? or CCD, by scientists as they seek to explain what is causing the bees to literally disappear in droves.
The usual suspects to which bees are known to be vulnerable such as the varroa mite, an external parasite which attacks honey bees and which can wipe out a hive,
appear not to be the main cause.
?CCD is associated with unique symptoms,
not seen in normal collapses associated with varroa mites and honey bee viruses or in colony deaths due to winter kill,? entomologist Diana Cox-Foster told the Congress committee."
http://www.commondreams.org/archive/2007/04/07/366/