Why are the bees vanishing?

Originally published on Grist.

By Nathanael Johnson

A decade ago, beekeepers in the United States started noticing that their honeybees were dying at suspiciously high rates each winter. It was a disturbing trend, given that these bees are so crucial for pollinating many of our favorite fruits and vegetables.

In the years since, honeybees kept dying at alarming rates, and experts realized we’ve got a potential crisis on our hands. It’s reached the point that President Obama has now taken a personal interest in the matter.

But losses during the spring and summer were still extremely high, and although experts still aren’t sure exactly why, parasites, pesticides, and poor nutrition are all plausible culprits.

Honeybees and wild bees alike are mysteriously dying off all over the world. And scientists have long struggled to pinpoint why, exactly, that is.

Some experts cite diseases and invasive parasites like the Varroa destructor mite, introduced from Asia and afflicting US honeybees. Others point to a new class of pesticides called neonicotinoids that mess with the nervous systems of insects. Still others blame the loss of wild habitat, as diverse flowers are replaced by suburban lawns or farms with just a few crops, impoverishing bee diets.

What’s less appreciated, however, is that beekeepers have been working frantically to rebuild lost bee colonies and transport bees to where they’re needed for pollination.

On the other hand, if bees keep dying off at very high rates, that good fortune could start to change.

Since 2006, honeybees in the United States have been dying at alarmingly high rates. And scientists are still exploring why.

Bee experts tend to cite a mix of different culprits: The parasitic Varroa destructor mite has been attacking honeybee hives in the United States. Poor nutrition caused by a lack of crop diversity may make the bees less resilient. And, on top of that, some newer pesticides do seem to make honeybees more susceptible to infections.

Honeybees in the United States are still dying at alarmingly high rates, putting billions of dollars of crops at risk.

But here’s some good news for a change: Fewer bees died in the winter of 2013-14 than the average over the past eight winters. What’s more, there are at least a couple of early, tentative signs that commercial beekeepers are getting a better handle on bee deaths.

That’s worrisome news for countries that depend on bees to pollinate their fruits and vegetables. The UN Food and Agriculture Organization has estimated that “out of some 100 crop species which provide 90% of food worldwide, 71 of these are bee-pollinated.” So, understandably, researchers are frantically trying to figure out what’s going on.

That brings us to Europe, where the European Commission just published a massive new study tracking 32,000 honeybee colonies across 17 states — the largest-ever study on honeybees and the diseases that affect them.