Countryfile 6th May 2012 examines recent evidence from Royal Holloway College, London and interviews Julian Little from Bayer and Miles Parker from DEFRA on concerns that neonicotinoids are having a major impact upon the bee population.
This link will only be active until 12th May http://www.bbc.co.uk/programmes/b01hpdjj
http://www.economist.com/node/21551451
IN THE winter of 2006 beekeepers in America noticed something odd—lots of their hives were dying for no obvious reason. As the months passed, reports of similar phenomena began coming in from their European counterparts. Mystified scientists coined the label “colony collapse disorder” (CCD) to describe what was happening. Since then, much brow-sweat has been expended trying to work out just what CCD really is.
Dying bees are a problem, and not just for apiarists. Bees pollinate many of the world’s crops—a service estimated to be worth $15 billion a year in America alone. And there is no shortage of theories to explain the insects’ decline. Climate change, habitat destruction, a paralysing virus, fungal infection and even a plague of parasitic mites have all been proposed. But one of the leading ideas is that the bees are suffering from the effects of neonicotinoids, a class of commonly used pesticides, introduced in the 1990s, which are toxic to insects but much less so to mammals.
Two papers published this week in Science lend weight to this idea. The first, from a group led by Penelope Whitehorn and David Goulson of the University of Stirling, in Britain, examined the effects these insecticides have on bumblebees, which are closely related to honeybees. Bumblebees are less studied than their honeybee cousins, but they also pollinate many commonly eaten crops, including strawberries, raspberries and runner beans.
The two researchers and their colleagues raised 75 bumblebee colonies in their laboratory. They exposed some, via contaminated pollen and sugar water, to high doses of imidacloprid, a type of neonicotinoid insecticide. Others were exposed to low doses (half as much as the high dose), or to no dose at all. Then, after two weeks of this treatment, the colonies were taken into the outside world and left there for six weeks, to see how the bees did.
All of the doses of imidacloprid, both high and low, that Dr Whitehorn gave her bees were “sublethal”—in other words, insufficient to kill the insects outright. Firms that produce pesticides, and the authorities that regulate them, are aware of the importance of bees to food production, and new products must be tested to make sure they are not fatal to helpful insects. But Dr Whitehorn found that even non-lethal doses of pesticide were bad for bees. Both the high-dose and the low-dose colonies grew more slowly than the undosed ones, gaining 8-12% less weight on average.
More importantly, the pesticides drastically inhibited the production of queens, which are needed to establish new nests each spring. (Unlike those of honeybees, bumblebee colonies do not survive the winter; they must be refounded by a hibernating queen.) The undosed colonies produced 13.7 queens, on average. Those given a small dose of insecticide produced two. Those given a high dose produced just 1.4. Worryingly, even colonies given the high dose may have got off lightly compared with their wild brethren. The researchers note that another British study found levels of imidacloprid in rape crops that were seven times higher than the food supplied by the researchers.
Dr Whitehorn’s paper does not propose a mechanism by which pesticides do their damage. But the second study, by a group led by Mickaël Henry at the French National Institute for Agricultural Research, in Avignon, may shed some light on the matter. Inspired by previous laboratory-based work, which had suggested that sublethal doses of neonicotinoids damage honeybees’ memories, their ability to forage, and their ability to navigate back to their hive afterwards, Dr Henry decided to conduct some tests in the wild.
To that end, he and his colleagues glued tiny radio transmitters to the thoraxes of worker bees. These triggered a detector on the hive whenever a worker bearing one returned from a foraging trip. Some hives were given realistic doses of thiamtethoxam, a variety of neonicotinoid, while others were left alone. Dr Henry found that around twice as many treated bees as untreated ones failed to return to the hive. That, mathematical models indicate, might easily cause a hive to collapse.
Colony club
Moreover, even if it did not do so alone, it could be a contributing factor. Many researchers believe the label “colony collapse disorder” covers a multitude of problems; that would account for the long list of possible causes. But neonicotinoids have the explanatory virtue of being a fairly recent development and also one which, as these two pieces of work suggest, could be a common factor in weakening a colony without actually pushing it over the edge. The killer blow would then be administered by something else: a mite infestation, perhaps, or a fungal infection, or whatever else happened to turn up that a healthy hive would have shrugged off. A paper published earlier this year in Naturwissenschaften, for example, showed that even small doses of neonicotinoids weakened bees’ resistance to Nosema, a common fungal parasite.
A few countries, including France, Germany and Slovenia, have already restricted the use of neonicotinoids because of worries about their effects on bees. It would help other places that are thinking of following suit if more realistic trials were conducted in the future, in conditions that mimic nature as closely as possible in the way that these two experiments have done. That might be more expensive than the present way of doing things, in which tests are mostly confined to laboratories and are concerned with finding out how much insecticide is needed to kill bees outright. But the growing evidence that insecticides damage bees in subtle ways means it would be money well spent.
Read the papers here;
Bleker and the bees (click to read the PDF) gives an interesting insight into how Bayer affects government policy through scientists it seems very proficient at controlling. Sadly for those involved the trail of evidence is easy to follow and as a consequence Tjeerd Blacquière of Wageningen Plant Research International (PRI) has emerged with his scientific credibility shredded.
This article is a translation of an article in Vrij Nederland magazine.
As the world’s farmers strive to produce more food, they rely on ever-increasing quantities of pesticides—which includes products to kill weeds, insects, and any other organisms that might threaten crops. Environmental groups warn that the extra food comes at a heavy cost, however, of severe harms to the health of farmers, consumers, and ecosystems everywhere. Tomas Brückmann, a project manager on pesticides and biodiversity for Friends of the Earth Germany—the German chapter of Friends of the Earth International, a worldwide federation of environmental groups—spoke about the pesticide dilemma with Rick Docksai, an assistant editor for THE FUTURIST and World Future Review.
THE FUTURIST: How would you characterize the overall pesticide use in Germany? Where is it trending—upward or downward?
Thomas Brückmann: The use of pesticides in public gardens is much too high, and on farmlands we have extremely high use of pesticides. And every year it is increasing. You have an enormous increase of glyphosate in Germany, and I think also in South America (editor’s note: Glyphosate is a popular weed-killer produced by agro-chemicals company Monsantor and marketed under the brand name Roundup).
THE FUTURIST: Why is pesticide use going up?
Brückmann: Farmers want to make a profit. With the high prices of food on the market, farmers are trying to meet the demands.
THE FUTURIST: What hazards do pesticides pose to wildlife?
Brückmann: We have had near extinctions of several bird species in the last 20 years in Germany, such as the grey partridge, northern lapwing, and the crested lark.
And we have large numbers of toads dying off. Toads live one or two months per year in ponds and the rest of the year on farmlands. So if we spray pesticides, it’s possible that we will kill the toads.
We also have a decreasing population of butterflies. And butterflies are a source of nutrition of the birds. The first to die, if you spray pesticides, are the butterflies, and a lot of the birds follow. This is the chain.
Additionally in Germany, we use a lot of herbicides, and this results in mass elimination of farmland weeds. Those weeds are another source of nutrition for other birds.
From the beginning of the 1990s, we have had a new group of pesticides produced by Bayer. This group is called neonicotinoids—same chemical that is in cigarettes. This group kills bees and is more dangerous than any other compound of pesticides. Henk Tennekes, a toxicologist in the Netherlands, called it “a disaster in the making.”
THE FUTURIST: What effects might pesticides have on human health?
Brückmann: An example of that would be a farmer in Saxony. His cows exhibited a disease, and then the farmer contracted the same disease. This disease is a strain of botulism, and it is known as a disease for cows, not for people. The doctors analyzed his blood and they found abnormally high concentrations of glyphosate.
We have a lot of new diseases—cancer, hormone disruptions, and others. In lesser developed countries, you have even worse problems. Farmers are using pesticides that are not allowed in the United States or in Europe. The multi-national companies such as Monsanto, Bayer, they have a big responsibility to protect people in farming countries from the use of pesticides, but they have not.
THE FUTURIST: I would like your thoughts on the “buffer zones” that I am told are constructed along some rivers that run near farms. How much protection can they provide the rivers from farms’ pesticide and fertilizer pollution?
Brückmann: Buffer zones are good possibilities to reduce the input of pesticides into rivers. But beyond buffer zones, we demand eco-farming, with 20% of the farmlands set aside for non-use, and along with that the use of better techniques, for instance, crop rotation (editor’s note: Crop rotation consists of alternately growing one crop on a field in one season and a different crop on the same field the following season; and every few seasons, growing nothing on it).
THE FUTURIST: Crop rotation would be a non-chemical alternative method for increasing farm produce?
Brückmann: It is. Our ancestors developed crop rotation to reduce insects, to produce more wheat and so on, and to improve the nutrition of the soil. If you use crop rotation, insects cannot settle there and live there through the next winter.
THE FUTURIST: What about weeds? What options do farmers have for controlling weed growth without herbicides?
Brückmann: We recommend use of regionally adapted plants. They are better protected against insects, against weeds, and against adverse climate conditions.
I will point out also that in Germany, consumer organizations in 2011 protested to the German government to reduce pesticide use. And now we have a pesticide-reduction action program—the government’s plans to reduce pesticides.
THE FUTURIST: It sounds like once you mobilized on the dangers of pesticide use, the government responded very quickly.
Brückmann: We have corporations and environmental NGOs fight together against the use of pesticides. And in Germany, more and more people buy organic food, since it is inexpensive and widely available in markets.
And all European Union member states have to develop programs to minimize use of pesticides (editor’s note: The Thematic Strategy on the Sustainable Use of Pesticides, approved by the European Commission in 2006, requires all EU member states to develop action plans to minimize pesticides’ potential harms to ecological and human health).
But the current regulations are not enough. Before a grower can use pesticides, the governmental agencies check it. But yet we have more and more diseases and damages to the environment through the use of pesticides.
Each farmer uses a lot of pesticides at the same time, and the combination of damages from multiple pesticides are not checked. Reactions between two compounds are very dangerous, and a lot of farmers use more than 10 different pesticides in one season. Therefore, a lot of people continue to become ill.
The recently published paper in Pest Management Science, entitled
has raised a storm of criticism. The authors conclude that neonicotinoid pesticides are not responsible for bee colony decline, but they also brand their own results as inconclusive.
Here Henk Tennekes summarises the problem with this kind of research.
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Most beekeepers need no convincing that pesticides, particularly neonicotinoids, are behind the massive losses in managed hives experienced now for several years. Faced with a strong beekeeper association and several influential environmental advocacy groups in the US, significant research funds have been directed towards finding the causes of colony collapse disorder (CCD), but it has been a frustrating time for beekeepers. To an outsider, it seems that many of the projects are directed at first ruling out all other potential causes before considering pesticides. This is the last thing that anyone appears to want to look at. …..Report from the CCD steering committee makes interesting reading (www.ars.usda.gov/is/br/ccd/ccdprogressreport2010.pdf). Everyone agrees that bees are sick, but surely it must be that we are stressing the bees by carting them around the country or not feeding them properly? It’s like watching a long spiral with the bullseye in the centre. You know where they should be heading, but they want to go all around the spiral first before they move in towards the bullseye. Two years ago, Dr Jeff Pettis, a leading ARS scientist in Pennsylvania, found an interesting synergistic effect between minute doses of imidacloprid and the microsporidia Nosema. Imidacloprid plus Nosema caused colonies to decline faster, a significant finding. In 2010 Alaux et al. in France, working independently, found the same effect, as did Vidau et al. (2011) with fipronil and thiacloprid in France. …Pettis appeared before the UK Parliament in March 2011 claiming that he still wasn’t convinced that neonicotinoids should be blamed for bee losses, because he couldn’t reproduce the results in the field. Yet field experiments are notoriously difficult to draw conclusions from because of the wide range of variables. This is particularly so for honey bees, which forage over many kilometres. You also have a product that has been shown to affect the immune system of honey bees at extremely low doses, almost below the limits of detection. It beggars belief that the world-wide loss of bees, and the corresponding release of neonicotinoids into the fields, forests and gardens of huge swathes of the world, is simply a coincidence. Particularly when we know that they do, in fact, exhibit the effects being seen in laboratory trials.
From: Where have all the ladybirds gone?
By Marilyn Steiner and Stephen Goodwin.
http://hydroponics.com.au/free-articles/where-have-all-the-ladybirds-gone-part-2
From The Independent Sunday 29th January 2012
Compelling new evidence from the US government’s top bee expert, Dr Geoff Pettis, that modern pesticides may be a major cause of collapsing bee populations led to calls yesterday for the chemicals to be banned.
A study published in the current issue of the German science journal Naturwissenschaften, reveals how bees given minute doses of the widely used pesticide imidacloprid became more vulnerable to infections from a deadly parasite, nosema.
http://www.independent.co.uk/environment/nature/pesticides-blamed-for-bee-decline-6296322.html
See also the article in The Economist http://www.economist.com/node/21543469
Dr Tennekes has been invited to speak on the sub-lethal effects of pesticides on bee colonies at the Hampshire Beekeepers Association Convention on 10th November 2012
For a complete picture on the threat that neonicotinoids pose to our ecosystem you cannot do better than to read Henk Tennekes’ book “A Disaster in the Making”
The book (pdf or hardback) can be purchased at www.disasterinthemaking.com
Anyone donating £10 or more to small blue marble will receive an electronic copy of the book.
On Saturday, the 27th anniversary of the Bhopal disaster in India that killed 20,000 people will be commemorated by World No Pesticides Use Day. This year, it is also the start of a three-day public trial of pesticide companies by the Permanent People’s Tribunal (PPT), an international opinion tribunal that has raised awareness of cases from Eritrea to Guatemala.
It will convene in Bangalore, India, to hear cases brought against the big six pesticide companies; Monsanto, Dow, BASF, Bayer, Syngenta and DuPont, which control 74% of the global pesticide market. The PTT will invite the companies to defend an allegation of violating human rights. The World Bank estimates that more than 350,000 people each year die of unintentional pesticide poisoning – close to 1,000 people a day. Pesticide Action Network (PAN) International, which is spearheading the PPT, says that up to 41 million people suffer from adverse effects of pesticide exposure.
read more at
http://www.guardian.co.uk/environment/blog/2011/dec/02/pesticides-bees
Henk Tennekes and Francisco Sanchez-Bayo are provisionally scheduled to give a presentation at the 6th SETAC World Congress in May, 2012 in Berlin entitled “Time-dependent toxicity of pesticides and other toxicants: implications for a new approach to risk assessment”
Authors: Tennekes, Henk, Experimental Toxicology Services Nederland BV, Zutphen, Nederland (Presenting author) and Sánchez-Bayo, F , University of Technology Sydney, Sydney, AustraliaFurther details: http://berlin.setac.eu/?contentid=404