Honeybees are dying less often in the winter and researchers have floated a new idea for an alternative to harmful pesticides.

Both the U.S. Department of Agriculture (USDA) and the Bee Informed Partnership have published a study in light of a phenomenon known as colony collapse disorder (CCD). Last week, a Harvard study linked CCD to two commonly used pesticides.

Bee Informed conducted a survey of 7,000 beekeepers who took a more careful approach to treating their colonies. The treatment centered on controlling parasitic Varroa mites, but the results showed a lower mortality rate. The problem is that it is a little known technique.

"We think we could take a bite out of some of these losses if you control the mites properly," Bee Informed Director Dennis vanEngelsdorp, an entomologist at the University of Maryland, told NBC News.

The USDA noted the annual Bee Informed survey (covering Oct. 2013 to April 2014) found the national honeybee mortality rate for this past winter was 23.2 percent, down from 29.6 percent a year ago. The downward trend is an encouraging sign, as honeybee winter mortality rate was 33.8 percent as recently as the winter of 2009-2010.

"Yearly fluctuations in the rate of losses like these only demonstrate how complicated the whole issue of honey bee heath has become, with factors such as viruses and other pathogens, parasites like varroa mites, problems of nutrition from lack of diversity in pollen sources, and even sublethal effects of pesticides combining to weaken and kill bee colonies," Jeff Pettis, survey co-author, said in a USDA news release.

Pettis also serves as lead researcher of the Agricultural Research Service (ARS) Bee Research Laboratory in Beltsville, Maryland, the USDA's chief intramural scientific research agency.

Varroa mites are Asian parasites that were first identified in the U.S. in 1987 and recent research suggests they are a leading cause of CCD. Winter has also been a factor, especially with the severe storms experienced in the Northeastern U.S.

"What is clear from all of our efforts is that varroa is a persistent and often unexpected problem," vanEngelsdorp said in the USDA release. "Every beekeeper needs to have an aggressive varroa management plan in place. Without one, they should not be surprised if they suffer large losses every other year or so. Unfortunately, many small-scale beekeepers are not treating and are losing many colonies. Even beekeepers who do treat for mites often don't treat frequently enough or at the right time. If all beekeepers were to aggressively control mites, we would have many fewer losses."

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