The U.S. Department of Agriculture recently released results of its annual survey of winter honeybee death losses, and they were significantly lower last winter.
Total losses from all causes were 21.9 percent for the winter of 2011-2012, a drop from each of the previous five years, where losses have ranged from 29 to 36 percent. Previous surveys reported colony losses of 30 percent in the winter of 2010/2011, 34 percent in 2009/2010, 29 percent in 2008/2009, 36 percent in 2007/2008, and 32 percent in 2006/2007, according to the USDA.
More than 5,500 beekeepers who manage about 15 percent of the nation’s 2.49 million colonies responded to the survey, which was conducted by the USDA, the Apiary Inspectors of America, and the Bee Informed Partnership.
Among the beekeepers responding, three in eight said at least some of their colonies died leaving no trace of dead bees, a sign of colony collapse disorder. It was not possible, given the nature of the survey, to determine how large a factor colony collapse disorder was.
Researchers speculated that the unusually warm winter may have resulted in the reduced losses, since winter cold is a major stress on bees.