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Photo courtesy of Kyle Anderson Photography |
Bee Deviled: Scientists No Longer Bumbling Over Cause Of Colony Collapse Disorder
Annie Spiegelman
Posted: 09/19/2012 12:14 pm
Though worldwide bee health has been on the decline since the 1990s, it wasn't until the fall of 2006 that beekeepers nationwide began noticing millions of bees vanishing from their hives. This syndrome, named colony collapse disorder, or CCD, is characterized by the disappearance of adult honey bees from the hive, leaving the newborns to fend for themselves.
If you're not a huge fan of the bee, why should this matter to you? Well, if you like to eat food, you should be concerned. Besides gathering nectar to produce honey, bees pollinate agricultural crops, home gardens, orchards and wildlife habitat. As they travel from blossom to blossom in search of nectar, pollen sticks to their furry body and is transferred to another flowering blossom enabling it to swell into a ripened fruit. It's estimated that about one-third of the human diet is derived from insect-pollinated plants and three-quarters of all plants on the planet depend on insects or animals for pollination.
Most scientists now agree that the main causes of colony collapse disorder are nutritional stress, pathogens (mites, viruses and fungus), and pesticides. Two recent studies published in Science strengthen the case that a relatively new class of systemic insecticides entitled 'neonicotinoid pesticides' are indeed key drivers behind recent pollinator decline.
Not knowing how to even pronounce the word neonicotinoid,I decided to contact Pesticide Action Network, North America, (www.panna.org) where trained agronomists, chemists, ecologists and analysts track and translate science, making it publicly accessible to the rest of us. I spoke with Heather Pilactic, Panna's Co-Director, about the recent bee die-offs and what consumers can do to support the struggling beekeepers.
According to PANNA's reading of the latest science, these new studies show that pesticides do play a significant role in honeybee deaths. How large a role?
How big a role neonics, or any other bee-toxic pesticides play in CCD and pollinator decline really depends on the situation. The relative contribution of each of these three main causes will vary with location, timing, exposure levels, genetic vulnerability of a hive, etc.in ways that defy meaningful quantification. But the really short answer is "big."
What we do know is that pesticides are absolutely driving bee losses in a number of different ways: Increased herbicide use (driven by RoundUp Ready GE crops) is killing off habitat that bees rely on for nutrition. As for older pesticides, foliar (spray) applications of any number of pesticides while bees are foraging, is still common practice.
Bees are especially vulnerable to many insecticides: when you spray when and where they are eating, they die. New science out of the University of Pennsylvania's bee team shows that adjuvants, or "inert" ingredients that make up the bulk of a pesticide product formulation are impacting bee health as well.
A new class of fungicides -- once rarely used on corn -- have since 2006 been widely promoted as yield boosters. What little we have studied about the effects of fungicides on bees points to their synergistic effects when combined with neonics (as they often are): they increase the bee-toxicity of the latter up to 1,141-fold. The chemistry of yet another new class of fungicides indicates that they have insecticidal effects. Emerging science further points to fungicides as killing off important bee "gut" microbiota -- such as the bacteria that bees rely upon to turn pollen into bee bread, or the friendly bacteria that combat infection.
That's depressing enough but there's more. (Hang in there, pilgrim.) What's all the talk we hear about neonicotinoid pesticides?
Neonicotinoids, covers at least 142 million acres of U.S. countryside, much of it corn -- on which bees rely heavily for protein. As systemics, these insecticides course through plants' vascular systems to be expressed in pollen, nectar and guttation droplets. This class also happens to be very long-lasting, so they are accumulating in the soil, and saturating the environment in ways we have yet to quantify.
The most widely used of these neonicotinoids (imidacloprid, clothianidin, thiamethoxam) are known to be highly acutely toxic to bees, and have a variety of sub-lethal effects ranging from disorientation to memory, immunity and reproductive impairment. These pesticides are clearly making bees sick, and dead -- but so do a lot of other pesticides. What makes these neonicotinoids suspect is that they are known to be highly toxic to bees, pervasive, long-lasting and relatively new. Perhaps coincidentally, the emergence of CCD in the U.S. roughly coincides with the 5-fold increase of the level of neonics used on corn seed: seed companies began marketing seeds treated with a 5X level of neonicotinoids (1.25 mg/seed vs. .25) in 2004.
The peril of the bees is sounding an alarm warning us of environmental degradation but we're be too busy texting, facebooking and watching reality TV to notice. What are they trying to tell us with all that buzzing and disappearing?
Bees are an indicator species. They signal the well being of our broader environment, so their message is important. It is also one that I believe we are capable of receiving. Our generation, and our children's generation face overwhelming environmental issues. How do we process climate change? Water and food shortages? Biodiversity collapse? In a sense, the escape to virtual worlds is understandable. But I think of saving the bees as one of those graspable, manageable things that we can accomplish -- and that when we do accomplish it, the effects will ripple and magnify. If we stop poisoning bees, they will thrive and the world we live in will be more resilient as a result.
Why are you picking on Bayer's clothianidin? Doesn't Bayer make chewable baby aspirin?
Bayer's clothianidin -- which is one of the most toxic substances to bees that we know of -- remains on the market, in our view, illegally. There is no valid field study supporting its registration. The backstory is long and sordid, and we're still on the case. What it comes down to is that EPA has long been using this little-known loophole called "conditional registration" to speed pesticides to market with little or no safety data in hand. According to the Natural Resources Defense Council, of the 16,000 current product registrations: 11,000 (68 percent) have been conditionally registered -- that's 2/3 getting an essentially free pass to market.
So the Environmental Protection Agency tests for safety after the product has been on the market? That's reassuring... I need to go hide under my bed.
Registrants (such as Bayer) are then supposed to submit safety data according to defined criteria on a set deadline. What they do instead is delay, deliberately ignore certain criteria, or otherwise game the system to avoid real oversight. In the case of clothianidin, the field study they submitted was so poorly done as to be laughable -- it had no control and was on the wrong crop (canola instead of corn). EPA originally accepted it, then downgraded it and then neglected to close the loop.
Sounds like the pesticide industry has the EPA by the balls . . .What can the public do to help shift policy decisions that can help bees, beekeepers and people who like to eat safe food?
Our food system has always been a political arrangement in one form or another. What's heartening about the last 5 years or so is that the conversation is widening because folks are realizing that this is a political issue much more so than a lifestyle one. More people are seeing themselves as stakeholders in a rigged food system, and doing something about it. And that's a good thing! That's democracy.
So the MAN is still calling the shots? That's getting so old!
It is true that corporations and wealthy people have too much power in government -- but that won't change unless ordinary people engage the political process. Members of Congress truly are motivated by speaking with constituents who have a story to tell and know their issue. Decision makers still read the local papers, especially opinion pages. Get in the habit of writing letters to the editor, or OpEds. Or, get in the habit of making one phone call a week on one issue or another; before you know it, you'll be getting meetings with decision makers. Nobody can do everything, but we can all choose one thing and do it. For my money, I say, "get informed and get in the ring." Go to our website (www.panna.org) to get engaged, or pick another group working on this issue. What matters is commitment.
What is the "Imminent Hazard" legal claim filed by beekeepers and environmental groups?
"Imminent hazard" is policy-speak for "emergency so pressing that EPA has authority to take immediate action." Bees dying off en masse, year after year, is an emergency by any meaning of the term, and we petitioned EPA urging them to take action on this basis. Earlier this month they declined to do so, sticking to their original 2018 timeline for completing the analysis of neonic's impacts on bees (decisions and implementation would stretch out further still).
Luckily, members of Congress are starting to pay attention. Senators Gilibrand, Leahy, Whitehouse, and most recently, Markey, have all sent letters to EPA essentially telling the Agency to hurry up.
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