Study links fungicide to bees' decline
Researchers have unearthed another reason that bees might be getting sick, and they suspect it's connected to common fungicides used on crops, such as blueberries and almonds, for which commercial honeybees are brought in as pollinators.
A study by the University of Mary released on Wednesday found that bees are more susceptible to a lethal parasite when they're exposed to fungus-killing chemicals. The reasons, still unknown, are being studied.
"Bees are bringing a lot of agriculture products home with them in the colony, which is not new," said Dennis vanEngelsdorp, the study's senior author. "We knew there were a lot of different exposures."
What caught the researchers' attention was the amount of fungicide coming into the hive, he said, "and how that fungicide, which you don't expect to have a negative effect on bees, had this measurable effect on the bees' ability to fight infection."
They're calling for federal regulations to restrict the use of fungicides, which had been seen as safe for bees, at times when pollinating insects are foraging, similar to those that affect the use of insecticides.
The research builds on a government-sponsored report last spring that took a comprehensive look at what was contributing to honeybee colony declines, which first emerged in 2006. The report, by the Environmental Protection Agency and the US Department of Agriculture, suggested a complex mix of problems.
It blamed parasites and disease, genetics, poor nutrition and pesticide exposure, as well as farming practices that don't give bees a pesticide-free buffer zone to forage in heavily developed agricultural regions.
The fungicide development presents a crucial dilemma, because bee colony collapse touches all aspects of American agriculture. The USDA estimates that a third of all food and beverages are made possible by pollination, mainly by honeybees.
Pollination contributes to an estimated US$20 billion to US$30 billion in US agricultural production each year.
Environmentalists are concerned about a class of pesticides known as neonicotinoids, which the European Union intends to ban from use on corn and sunflowers at the end of the year.