Bee Decline Mystery Solved? Neonicotinoid Pesticides May Cause Colony Collapse Disorder

The Internet is abuzz with some exciting news: Two studies published in Science on Thursday may finally explain the alarming decline in bee populations over the last six years.

Since 2006, beekeepers have been reporting a mysterious and dangerous drop-off in the global population of honeybees. The problem attracted national attention -- over a third of U.S. commercial bee colonies were lost in 2008. Alarms were raised and meetings were called, from gatherings in small rural communities to committee hearings in Congress.

A North Carolina grower named Robert Edwards summarized it for the House of Representatives Agriculture subcommittee on Capitol Hill: No bees, no crops. The problem had dire implications for farmers, florists and horticulturalists.

The phenomenon was dubbed colony collapse disorder. It was like a weird horror movie in miniature: Hordes of worker bees would disappear from the hive, but their bodies were nowhere to be found.

Finally, researchers say, we may be close to solving the mystery. The two studies point to pesticides called neonicotinoids, which were rolled out in the 1990s. They became popular because they were less toxic to humans than other pesticides. But some recently leaked Environmental Protection Agency papers suggested that the chemicals hadn't been thoroughly tested enough to ascertain their effect on bees and other insects, according to Wired.

Now it appears that neonicotinoids have disastrous effects on bees' sense of direction. Since the insects can fly for miles in order to gather food, they rely heavily on their navigational abilities, employing a natural GPS of sorts. But when they're exposed to these pesticides, their innate equipment goes haywire.

A whole lot of them may have gotten bewildered out there, and many just never made it back to their hives. They dropped dead in relatively faraway places, according to the study, which may explain the apparent lack of dead bee bodies. And with the resulting decrease in food at the hive, whole colonies were endangered and fewer queen bees were produced.

The studies didn't answer all questions conclusively. One of them, conducted by French researchers, studied honeybees. But the other, carried out in the United Kingdom, focused on bumblebees -- even though those insects do not suffer from colony collapse disorder. Critics have said that the two findings contradicted each other in some areas, according to the New York Times.

And even if the studies can be trusted, they don't completely explain the global scale of the bee problem. Other factors are no doubt contributing, such as bee pathogens and an overall decrease in undeveloped land.

Still, the findings represent a big step in solving a very serious problem, taking some of the sting out of a mystery that has baffled scientists for years.