Leading entomologist Marla Spivak: 'We can have both pesticides and pollinators'

To grasp our bees' plight and prospects, stay focused on food

From MINNPOST

Issue By Ron Meador | Published 03/11/2015 · Link to Article

Dr. Marla Spivak, MacArthur Fellow and Distinguished McKnight Professor in Enyomology at the University of Minnesota says “To grasp our bees' plight and prospects, stay focused on food.” The University of Minnesota has maintained an internationally recognized research, teaching, and outreach program on honey bees since 1918. Minnesota together with Wisconsin, and North and South Dakota is the top honey-producing region in the US. Spivak believes that if bees have proper nutrition they’re actually able to detoxify pesticides, their immune systems are bolstered and they can fight off diseases.

As I listened to Marla Spivak discuss the plight and prospects of our honeybees last Monday it occurred to me that I was watching a masterful application of Albert Einstein’s principle that complex matters should be made as simple as possible – but not simpler.

Most of us have grasped by now that honeybees are under pressure from multiple sources, with certain insecticides, habitat loss, parasites and disease in the leading roles. But great argument continues over how to weigh their contributions:

               Commercial beekeepers assign most of the blame to neoicotinoid insecticides, a new type of systemic bug-killer whose surge in U.S. market share roughly coincided with the appearance of hive-emptying “colony collapse disorder” in 2006.

               Neonics’ manufacturers, vendors and applicators of course want to fix the fault elsewhere, and typically prefer the parasitic varroa mites – a problem, after all, that can be addressed by buying and applying a miticide.

               Many an entomologist and environmentalist emphasizes the role of habitat loss, the conversion of wild land into row crops, parking lots, golf courses and residential lawns that, for a flower-seeking honeybee, are more barren than a desertscape.

Spivak, who holds a McKnight professorship in entomology at the University of Minnesota and directs the Bee Lab there, knows as much about these matters as anyone. And her opinions are more influential than most.

To gauge her authority, you could try a Google search on, say, her name plus “bees” or “pollinators.” I did that on Sunday and came up with more than 11,000 hits across a wide variety of news, policy, university and government sites.

Why food is at the center

From Spivak’s perspective, all of these contending views are partly right and partly wrong. She feels that if you really want to understand what’s going on with bees – and what can be done to help them – you have to keep your focus on the food. For starters, the notion that bees are dying off in just one way – the way labeled “colony collapse disorder,” with bees suddenly vacating their hives en masse, never to return – is outmoded.

National surveys made since the initial appearance of CCD in 2006 and 2007 have now established that “actually, a very small proportion of colonies that are dying are dying from those particular symptoms.”

It happens – but the majority of colonies are dying for many, many reasons. From the mites, from bad nutrition, from not enough honey, from pesticides. ... Surprisingly few are being killed only by pesticides, really, but from diseases and pests and all of the interactions that seem to be happening.

Still, the overall losses continue at levels that most commercial beekeepers consider financially unsustainable: 30 percent of hives, or more, in some recent years, with a slight improvement last year. And most of these pressure factors, if not all of them, could be offset to some degree by a better supply of clean and convenient food, which for bees consists entirely of flower products.

The protein part would be pollen, and the carbohydrate part would be the nectar. ... That’s all they eat. They get all of their nutritional requirements from that, and nutrition is at the base of everything.

So when bees have good nutrition, they’re actually able to detoxify pesticides. ... Their immune systems are bolstered ... and they can fight off diseases. Unfortunately, what we’re giving bees in place of flowering fields is corn planted on every available acre, plus some soybeans. Neither crop is useful to bees.

Of course, corn sheds a lot of pollen for a short time in August when it’s tasselling, and bees do collect corn pollen, but it’s not very nutritious for them – it’s a wind-pollinated plant, and of course bees prefer plants that need an animal to move their pollen from flower to flower.

On top of that, in our cities we have huge expanses of lawns – another flowerless landscape which nobody may ever play on or even walk on, except for the guy who’s maintaining the lawn with the power mower, the herbicides, the pesticides, the fertilizers.  

 

Not one pesticide problem but many

Addressing indirectly the calls to ban neonicotinoids, said that analysis of pesticide residues in bee-gathered pollen is showing neonics “very rarely – but you find everything else.”

And the other thing we need to understand about our insecticides is that – let me put it this way: If you go to the pharmacy, or if you take an aspirin, any drug for yourself, the active ingredient will be labeled, and the inert ingredients will be labeled.

If you go to a pesticide label, only the active ingredient will be there. The inert ingredients are all proprietary information, they’re not revealed, and some of these, quote, inactive ingredients are actually more toxic than the active ingredient.

Genetically modified crops aren’t a problem per se for bees, Spivak said, but their widespread use has driven a massive increase in herbicide applications. No direct toxicity, again, but a major hit to habitat.

We grow Roundup-ready plants, which allows us to apply a lot of herbicide to kill of all the weedy flowers in the field without killing the crop. But many of those weedy plants have flowers that bees depend on for their food, and so the dramatic increase in herbicides is killing off the food for bees in many locations.

All in all, Spivak said, she agrees with the assessment of a commercial beekeeper in North Dakota who said, “ ‘Honeybees, wild bees and other pollinators are reduced to feeding on scraps.’ It’s a very sad state of affairs, and that sums it up very well.”

As for possible solutions, Spivak offered these thoughts:

            Bee lawns are a hot new topic for her researchers, offering the possibility of mowable green carpets surrounding our homes that still offer some flowering forage. Certain fescues, better adapted to northern climates anyway, could replace Kentucky bluegrass with grasses that bloom a bit and require less maintenance. Restoring Dutch clover and other ground covers that used to be more common is another possibility to be investigated.

            Bee-friendly buffers along roadways, Spivak said, would be “the most amazing thing we can do” to create large areas of new forage in a hurry, and other states – including Iowa – have gained some experience we can learn from. It’s a good idea, too, to take bees’ foraging needs into account in other types of public-lands restoration.

           Bee-friendly residential gardens are already a popular initiative, Spivak said, but there’s room for a more organized collection and sharing of information resources.

 Planting for pollinators is a new thing. We’ve had butterfly gardens, we’ve had rain gardens, and we’ve had programs to help people build these, but we don’t have pollinator-garden recommendations. We know that most of our native perennials will be good for native bees and honeybees, and we know that some of our annual bedding plants are not at all attractive to bees.

 

In the meantime, she advises gardeners to spend some time hanging around the nursery, watching to see which plants the bees linger on – then buy those.

Bee chow on the way? As both commercial and backyard beekeepers have turned to supplementary feeding to make up for scarce foraging territory, she said, much has been learned about what works well and what doesn’t. High-fructose corn syrup, for example turns out to be lacking in certain necessary nutrients found in nectar.

 

Because of the bee die-offs that we’re seeing, many researchers are saying, let’s give them things that are more aligned with what bees eat naturally. In fact, Purina just  put out a big job description – they’re looking for a researcher to study a better bee food, derived more from plant pollen and other plant ingredients. This is going to happen, and it’s going to happen fairly soon.

 

On the pesticide front, Spivak noted that federal regulators continue to gather evidence – some from her Bee Lab researchers – as they proceed toward a decision on re-registering neonics a few years from now. And she thinks it would be sensible to begin requiring disclosure of all toxic compounds in a pesticide, whether considered active or not.

But the prospects for a sea change are slim. And she’s OK with that.

Pesticides aren’t going away, that’s just reality. But we can have both pesticides and pollinators, and we’re going to have both.

We can do this. I know we can.

 

 

 

 

 

 

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