Across the planet honeybees have been in decline. A mysterious disorder leaves hives, full in the fall, empty come spring. The bees are gone, but the bodies missing. It’s a problem with a name—Colony Collapse Disorder—but without a known cause. Advocates, politicians, reporters and even some scientists have pet theories about the cause—pesticides, intensive agriculture, mites—but the reality is we just don’t know the true cause just yet. In all likelihood, it’s a combination of factors.
In a new study, researchers at the University of Illinois add one more. They found that high fructose corn syrup and other honey substitutes—sugary substances fed to bees in place of the honey we take from them—may be related to the recent dramatic decline in bee populations. According to the Los Angeles Times, eating honey made from pollen gives bees a chemical that they need to help break down the toxins in pesticides.
Although pollen winds up in the honey produced by Apis mellifera, these bees used to pollinate crops spend more time sipping on the same sugar substitute that is ubiquitous in processed foods – high-fructose corn syrup. The honey substitute is an important way for the industry, which contributes about $14 billion to the U.S. economy, to make ends meet.
The finding paints a picture of the complex interaction of forces that may be keeping the bee down: a bad diet makes them more susceptible to pesticides. Pesticides may, in turn, make them more susceptible to varroa mites, another contender for the cause behind CCD.
“People would love to have the one solution, but the problems is it really does seem like it’s a combination of factors,” Berenbaum said. But a compromised immune system, she added, could complicate all of the identified factors.
The researchers found that p-coumaric acid, a compound derived from plants, is “a key compound that revs up the bee’s defense system.” High fructose corn syrup and other replacements don’t have this, making the bees more susceptible.
Research in the 1970s had suggested that there were no health consequences or increased hazards associated with feeding bees on high-fructose corn syrup. But that was before beekeepers began putting mite-killing chemicals in hives, and before an entire class of agricultural pesticide was introduced.
Something is certainly going wrong with our bees, but as research builds it’s a reminder that it is going to take a wide-angled approach to figure out what’s going on and fix it.
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