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Your Day in Bug News: Fungicides are Bad For Bees Too


Someone probably forwarded you this study already. It was published in PLOS today. I’m not saying that you shouldn’t read it, because reading studies is fun, but if you don’t have much time here’s the gist: fungicides are bad for bees.

This is unfortunate, because everything seems to be bad for bees. Here are a few specific things that seem to be bad for bees right now:

Neonicotinoids are bad for bees. Or good for bees. Or not really that good for bees. They’ve been banned for use on flowering crops by the European Union for the next two years ,which will ideally show us if beehives do better when they’re not around, though there is some debate as to how long they stay in the soil .We’ll see how that goes.)

Corn syrup is bad for bees, at least when they have nothing else to eat because someone took away all their honey and sold it on the commodities market. The modern hive does not eat as well as its ancestors did — it’s hired to pollinate large acres of monoculture, and that doesn’t make for a very diversified diet.

Varroa destructor, is bad for bees. It’s actually the worst for bees. It’s the Darth Vader of bees. It killed off half the kept colonies and all of the wild colonies in America in the 1990's. It is, however, not very popular with journalists because unlike Colony Collapse Disorder (CCD) it was never a mystery — just a little hemolyph-sucker from Asia shaped like a kidney bean with tiny hairy legs. Journalists are simple. Faced with a fanged bean with legs and a mystery, we’ll always pay more attention to the mystery.

Inbreeding is bad for bees. American hives lost a lot of their genetic diversity during the varroa suckfest and there’s a near-complete ban on the importation of bees, for fear they’ll bring something new and terrible with them. The USDA did a good job with its importation of varroa-resistant Russian queens, but that alone isn’t enough to restore the genetic diversity — and the opportunities that carried for disease resistance — that were lost in the ‘90's.

So what does it mean now that it looks like fungicides are bad for bees too? Hard to say. Some commercial beekeepers use fungicide in their hives because fungicide also kills varroa. Will they stop? Depends on how bad their varroa problem is — they might prefer to have a weak colony without varroa than no colony at all because varroa ate all its life juices.

The paper recommends that beekeepers avoid placing their hives in locations where pesticides and fungicides have been used (or used recently). But since honeybees can travel up to a mile on their own and over 3,000 miles when you wrap up their hive and load them onto the back of a flatbed truck, that’s a lot of acreage to ask about. Also: many pollination contracts are locked down months in advance, which is plenty of time for a strange fungus to show up and inspire a farmer to hose down their entire crop with fungicide, no matter what they said earlier about not spraying in the weeks before the honeybees show up.

But wait! Is there anything about this study that has a practical application? There is. On a side note, the researchers noticed that of the seven crops the test honeybees had been hired to pollinate, the bees weren’t returning to their hives with any pollen from blueberry, cranberry, cucumber, pumpkin and watermelon flowers. Instead, they were bringing back pollen from weeds — probably whatever was growing at the edge of the field.

If the honeybees weren’t bringing back pollen from the plants they’d been hired to pollinate, odds are they weren’t pollinating them and helping them make little plant babies. Why might this be?

Well, all of the rejected plants — blueberries, cranberries, pumpkins, cucumbers — are native to the Americas. Honeybees aren’t. They were floated across the Atlantic by colonists eager to a) eat honey b) make booze or c) pollinate the apple trees they had floated over earlier.

If honeybees are truly disinterested in native plants, that would mean that their pollination should be (and possibly is being already) carried out by native bees, which are less exciting than honeybees (no honey) but which are also not experiencing an enormous wide-scale mysterious die-off. At least not that we’ve noticed.

The honeybee is the only pollinator that can work in our current monoculture-based way of growing things (more on that later). Our chances for finding another pollinator with its particular skills are practically nil.

But it’s worth working on how to use native bees more for pollination. Plenty of scientists have been saying this (Claire Kremen, in particular, won a MacArthur for saying it) but it’s still considered to be a research topic on the fringes, rather than one worthy of the big money.

This study, for all that it was motivated by the honeybee’s dominance as our go-to pollinator, turns out to be more of an argument for why that dominance should change.