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... now it seems that the dangerous varroa-mite was mainly responsible for the death of approx. 300k (out of only 1m!) bee colonies in Germany during winter 2011/12 :(
Pesticides aren't the biggest factor in honeybee die-off, EPA and USDA say~ May 2, 2013 ~ Last month, beekeepers and environmentalists filed a federal lawsuit calling for an immediate ban on two kinds of neonicotinoids — clothianidin and thiamethoxam.
Bee deaths stir up renewed buzz - Cosmic Log
HONEY BEES | Virus Named as Possible Factor in Honey Bee Disappearance