The cause of Colony Collapse Disorder

on Sunday, 01 May 2011. Posted in Environment

Commercial beehives pollinate over a third of North America’s crops and this pollination encompasses everything from fruits like peaches, apples, cherries and strawberries to ninety percent of nuts. Crops of wheat, corn, and many other condiments are part of this marvelous process of pollination. Without pollination, most crops would simply cease to exist.

What is Colony Collapse Disorder?

Colony Collapse Disorder or CCD, is the name given to the mysterious decline of honeybee populations around the world beginning around 2006. Each winter since, one-third of the United States honeybee population has died off or disappeared (more than twice what is normal). While CCD appears to have multiple interacting causes including pathogens, a range of evidence points to sub-lethal pesticide exposures as important contributing factors.

Neonicotinoids are a particularly suspect class of insecticides, especially in combination with the dozens of other pesticides found in honeybee hives. Key symptoms of CCD include: 1) inexplicable disappearance of the hive’s worker bees; 2) presence of the queen bee and absence of invaders; 3) presence of food stores and a capped brood.

The crisis of CCD in the honeybee population is an increasingly widespread phenomenon of bees disappearing or abandoning their hives. Bayer CropScience, the manufacturer of one of the implicated pesticides, imidacloprid and clothianidin, dismisses the pesticide connection. But countries, including France, Germany and Italy, have taken steps to limit their use, along with other pesticides like fipronil. The National Union of French Beekeepers brought the problem to national attention and forced their government to restrict these pesticides. The US lags behind, outside the glare of public outrage and protests that have been seen in Europe.

Bees support our environment, pollinating half the flowering plant ecosystem and one-third of agricultural plants. The disappearance of the bees alerts us to a fundamental and systemic flaw in our approach to the use of toxic chemicals – and highlights the question as to whether our risk assessment approach to regulation will slowly but surely cause our demise without a meaningful change of course.

Beekeepers ask EPA to remove pesticide

Beekeepers and environmentalists cited a leaked EPA (US Environmental Protection Agency) memo that discloses a critically flawed scientific support study. The November 2nd (2010), memo identifies a core study underpinning the registration of the insecticide clothianidin as unsound after EPA quietly re-evaluated the pesticide just as it was getting ready to allow a further expansion of its use. Clothianidin (product name “Poncho”) has been widely used as a seed treatment on many of the country’s major crops for eight growing seasons under a “conditional registration” granted while EPA waited for Bayer CropScience, the pesticide’s maker, to conduct a field study assessing the insecticide’s threat to bee colony health.

Bayer’s field study was the contingency on which clothianidin’s conditional registration was granted in 2003. As such, the groups are calling for an immediate stop-use order on the pesticide while the science is redone, and redesigned in partnership with practicing beekeepers. They claim that the initial field study guidelines, which the Bayer study failed to satisfy, were insufficiently rigorous to test whether or not clothianidin contributes to CCD in a real-world scenario: the field test evaluated the wrong crop, over an insufficient time period and with inadequate controls.

According to beekeeper Jeff Anderson, who has testified before EPA on the topic, “The Bayer study is fatally flawed. It was an open-field study with control and test plots of about 2 acres each. Bees typically forage at least 2 miles out from the hive, so it is likely they didn’t ingest much of the treated crops. And corn, not canola, is the major pollen-producing crop that bees rely on for winter nutrition. This is a critical point because we see hive losses mainly after over-wintering, so there is something going on in these winter cycles. It’s as if they designed the study to avoid seeing clothianidin’s effects on hive health.”

According to James Frazier, PhD., professor of entomology at Penn State’s College of Agricultural Sciences, “Among the neonicotinoids, clothianidin is among those most toxic for honey bees; and this combined with its systemic movement in plants has produced a troubling mix of scientific results pointing to its potential risk for honey bees through current agricultural practices. Our own research indicates that systemic pesticides occur in pollen and nectar in much greater quantities than has been previously thought, and that interactions among pesticides occurs often and should be of wide concern.” Dr. Frazier said that the most prudent course of action would be to take the pesticide off the market while the flawed study is being redone.

Clothianidin has been on the market since 2003. With a soil half-life of up to 19 years in heavy soils, and over a year in the lightest of soils, commercial beekeepers are concerned that even an immediate stop-use of clothianidin won’t save their livelihoods or hives in time.

“We are losing more than a third of our colonies each winter; but beekeepers are a stubborn, industrious bunch. We split hives, rebound as much as we can each summer, and then just take it on the chin – eat our losses. So even these big loss numbers understate the problem,” says 50-year beekeeper, David Hackenberg. “What folks need to understand is that the beekeeping industry, which is responsible for a third of the food we all eat, is at a critical threshold for economic reasons and reasons to do with bee population dynamics. Our bees are living for 30 days instead of 42, nursing bees are having to forage because there aren’t enough foragers and at a certain point a colony just doesn’t have the critical mass to keep going. The bees are at that point, and we are at that point. We are losing our livelihoods at a time when there just isn’t other work. Another winter of more studies are needed so Bayer can keep their blockbuster products on the market and EPA can avoid a difficult decision, it’s unacceptable.”

Citing the imminent economic and environmental hazards posed by the continued use of clothianidin, the National Honey Bee Advisory Board, Beekeeping Federation, Beyond Pesticides, Pesticide Action Network, North America and Center for Biological Diversity are asking EPA administrator Lisa Jackson to exercise the Agency’s emergency powers to take the pesticide off the market.

“The environment has become the experiment and all of us – not just bees and beekeepers – have become the experimental subjects,” said Tom Theobald, a 35-year beekeeper. “In an apparent rush to get products to the market, chemicals have been routinely granted ‘conditional’ registrations. Of 94 pesticide active ingredients released since 1997, 70% have been given conditional registrations, with unanswered questions of unknown magnitude. In the case of clothianidin those questions were huge. The EPA’s basic charge is ‘the prevention of unreasonable risk to man and the environment’ and these practices hardly satisfy that obligation. We must do better, there is too much at stake.”

This documentation is republished with the kind permission of beyondpesticides.org

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