Guest blog – Are neonicotinoid pesticides responsible for the demise of bees and other wildlife? – by Rosemary Mason and Derek Thomas

Dr Rosemary Mason and Dr Derek Thomas are long-standing environmentalists

One of us has just returned from Orkney, where for the first time, we found the rare great yellow bumble bee (Bombus distinguendus), now restricted to Northern Scotland and the offshore islands. She was leisurely foraging on red clover and garden knapweed on a track at the edge of Kirkwall, the biggest town on Mainland.

I had been to Orkney some 25 years before to see the hen harriers. They had been studied by Eddie Balfour until his death in 1974 and later described by Donald Watson in ‘The Hen Harrier’, his impressive monograph about this iconic bird published in1977. However, over the last 20 years or so, the massive decline in invertebrates (animals without backbones) is a much more terrifying prospect than loss of a single rare species. Of course, many people don’t care much about invertebrates and would say “so what?” But all higher species (including humans) are completely dependent on them. Birds, amphibians and bats feed on insects, most crops depend on their pollination services and microbes recycle nutrients in soil and aquatic ecosystems.

What is most worrying is that many modern scientists seem to have little understanding of the environment. In 2006 the Government closed almost all of the Wildlife Research Stations, made 200 field scientists redundant and transferred the money into universities where it could be used for “hard” science; computer-driven population ecology and statistics. It is no longer fashionable to look at the environment. However, you don’t need science to show the declines in insects; twenty-five years ago if you went on a 300-mile journey in the UK, you would probably have to stop to clean the windscreen and headlights at least once. In June 2004, using a “splatometer” on their vehicle number plates, 40,000 drivers recorded an average of one squashed insect every 5 miles.

In 1991, Bayer CropScience introduced a new type of insecticide into the US; imidacloprid, the first member of a group now known as the neonicotinoids. Bayer Scientist Abbink certified that: “imidacloprid is the first highly effective insecticide whose mode of action has been found to derive from almost complete and virtually irreversible blockage of post synaptic nicotinic acetylcholine receptors (nAChRs) in the central nervous system (CNS) of insects.” Imidacloprid differed from conventional spray pesticides in that it could be used as seed dressings or soil treatments. When used as a seed dressing the insecticide will migrate from the stem to the leaf tips, and eventually into the flowers and pollen. Bees, bumblebees, hoverflies and butterflies that collect contaminated pollen or nectar from the crop will ingest a small dose of the toxin, but any insect that feeds on the crop will eventually die. The neonicotinoids were introduced into an environment that had already been affected by many toxic chemicals, some of which were persistent in the soil. In 1994 imidacloprid was licensed for use in Europe. In July 1994 beekeepers in France noticed something unexpected. Over the course of a few days, just after the sunflowers had bloomed, a substantial number of their hives would collapse, as the worker bees flew off and never returned, leaving the queen and immature workers to die. The French beekeepers soon believed they knew the reason; a brand-new insecticide called Gaucho® with imidacloprid as active ingredient was being applied to sunflowers for the first time. It took the French beekeepers nearly 10 years get bans on imidacloprid on sunflowers and maize, and for fipronil on all crops. During this time the National Union of Beekeepers organised two mass demonstrations in Paris and their President, Henri Clement, survived a personal court action against him by Bayer (the charge was that he had defamed their products). He was able to defend himself by citing the 2003 findings of the Comité Scientifique et Technique that linked low doses of imidacloprid to the disorientation and disruption of foraging. The summary was clear: “The treatment of sunflowers is a significant risk to bees in several stages of life”.

 

British reaction compared with the French

In contrast to their French counterparts, the British Beekeepers Association (BBKA) had been receiving money from the pesticides industry for endorsing safe pesticides; they were therefore in denial about the neonicotinoids. A BBKA motion tabled by members in January 2011 forced them to stop receiving money, but in June 2011 Tim Lovett was found to be featuring in a video promoting Bayer’s anti-varroal medicine as part of an EU symposium on Bee Health. A large group of beekeepers in the UK has now broken away and Phil Chandler has formed a separate organisation, http://www.friendsofthebees.org/

 

Dr Henk Tennekes, independent toxicologist

In November 2010, we discovered Dr Henk Tennekes’ new book: “Systemic Insecticides: a disaster in the making.” Dr Tennekes said that his book: “catalogues a tragedy of monumental proportions regarding the loss of invertebrates and subsequent losses of the insect-feeding (invertebrate-dependent) bird populations in all environments in the Netherlands. The disappearance can be related to agriculture in general, and to the neonicotinoid insecticide imidacloprid in particular, which is a major contaminant of Dutch surface water since 2004. The relationship exists because there are two crucial (and catastrophic) disadvantages of the neonicotinoid insecticides: the damage to the central nervous system of insects is virtually irreversible and cumulative. Tennekes showed that there is no safe level of exposure, and even minute quantities can have devastating effects in the long term. They leach into groundwater and contaminate surface water and persist in soil and water chronically exposing aquatic and terrestrial organisms to these insecticides. “So, what, in effect, is happening is that these insecticides are creating a toxic landscape, in which many beneficial organisms are killed off.” Tennekes and Sánchez-Bayo (Dr Francisco Sánchez-Bayo is an ecotoxicologist from Sydney) in a more recent paper demonstrated that chemicals that bind irreversibly to specific receptors (neonicotinoids, genotoxic carcinogens and some metals) will produce toxic effects in a time-dependent manner, no matter how low the level of exposure.

 

Mammals are being affected, not just pollinators

In 2000, researchers in an agricultural journal had shown that neonicotinoids acted on mammalian nAChRs as well, but it was considered that the selective nature of their binding (i.e. less affinity than in insects) made it safe for human exposure. There is now significant independent research to show that neonicotinoids have adverse effects on mammalian receptors and are having impacts on human health.

 

Massive exposure to the neonicotinoids of a global public that is totally unaware

In England, for example, in 2010, about one third of arable land was treated with neonicotinoid insecticides out of a total cropped acreage of about 9.9 million acres. Some fields had up to four applications of various pesticides.  In Scotland in 2010 clothianidin was used on all crops in an area of about 25,000 acres, and thiamethoxam on an area of about 47,000 acres. In the US in 2010, 88 million acres of maize, 77 million acres of soya and 53 million acres of wheat were treated with neonicotinoid insecticides. However, in the UK, it is impossible to tell whether or not a field of rape, for example, has been grown from seeds coated with pesticides. In addition, they are used commercially as spray preparations on greenhouse-grown salad crops and vegetables, plant bulbs, and container-grown ornamental/house plant production for indoor and outdoor use and also pet products for fleas. There are at least four products for domestic garden use. Bayer Garden Products include Provado® Ultimate Bugkiller Concentrate (thiacloprid), Provado® Lawn Grub Killer (imidacloprid), Ultimate Bugkiller Ready to Use (thiacloprid) and Provado® Vine Weevil Killer (thiacloprid). They are used on golf courses, playing fields etc.

In 1991, the same year as the US EPA registered the first systemic neonicotinoid, imidacloprid, the US Geological Survey (USGS) implemented a National Water-Quality Assessment (NAWQA) Program “to develop long-term consistent and comparable information on streams, rivers, ground water, and aquatic systems in support of national, regional, State, and local information needs and decisions related to water-quality management and policy.”

In 2009, NAWQA published a Report: Pesticide Trends in Corn Belt Streams and Rivers (1996-2006). The USGS authors of the Report said: “The declines in pesticide concentrations closely followed the declines in their annual applications, indicating that reduced pesticide use is an effective and reliable strategy for reducing pesticides contamination in streams.” One of the first national studies on the presence of pesticides in ground water had been published in 2008. Laura Bexfield who conducted the data analysis said: “The results of this study are encouraging for the future state of the nation’s ground-water quality with respect to pesticides. Despite sustained use of many popular pesticides and the introduction of new ones, results did not indicate increasing detection rates or concentrations in shallow drinking water resources over the 10 years studied.” However, the 44 insecticides, pesticides and degradation products that NAWQA were measuring did not include the neonicotinoid insecticides or the herbicide, glyphosate. They are not measured in Europe or in the UK either.

 

Shift in pest management on crops worldwide

Over the last 20 years, the shift in worldwide pest management has moved away from reactive to prophylactic. Now many fungicides, pesticides and herbicides are applied to the seeds before sowing. Application of the chemical before pest damage has occurred often involves routine, calendar-based spraying and pre-emptive treatments. It is like humans taking permanent antibiotics. In the US where GM, herbicide tolerant crops are widespread, the phenomena of insect and herbicide resistance have locked US farmers into a pesticide treadmill. Target pests and weeds are capable of becoming resistant to the repeated use of a single insecticide or herbicide such that successively larger doses have to be applied. Farmers and weed scientists across the US heartland and cotton belt are now struggling to devise affordable and effective strategies to deal with the resistant weeds emerging in the wake of herbicide-tolerant crops.

 

What is the truth about the Varroa mite?

Pesticide companies and their supporters blame Varroa mite, or one of the many viruses that have been found in dead and dying bees, for Colony Collapse Disorder (CCD). However, infection with Varroa, or any of these pathogens, is a symptom, not a cause.

 

Immune suppression associated with the neonicotinoids

Three papers between 2009 and 2012 from Bee Researchers in France and the US show that the administration of tiny amounts of various systemic neonicotinoids (imidacloprid, thiacloprid) and fipronil, to Colony Collapse Disorder (CCD) bees was associated with a weakening of bee immunity, such that they became more susceptible to bee diseases. In fact, although Varroa mite had been identified earlier, it wasn’t until 1995 that it started killing bee colonies in the US.  In 2006, full CCD was confirmed in the US, the same time as massive declines in bats were reported as a result of infection with a fungal pathogen, which causes White Nose Syndrome. This pathogen has wiped out whole bat colonies in many parts of the US.

 

Multiple calls for Defra, the US EPA and the EU to ban neonicotinoids

Many organisations worldwide have asked for a ban on neonicotinoids. Correspondence with European Commission Civil Servants, the US EPA, Defra, the UK Chemical Regulation Directorate and the Australian Pesticides and Veterinary Medicines Authority yielded almost identical responses; that there was no evidence that the neonicotinoid insecticides were harmful to bees. However, we found that all the registration documents said that they were highly toxic to honey bees and other pollinators and highly toxic to aquatic invertebrates.

 

Austrian Ombudsman Board calls for an investigation

On April 17th 2012 the EU Ombudsman opened an investigation into bee mortality and neonicotinoid insecticides following a complaint from the Austrian Ombudsman Board, alleging that the European Commission (EC) had failed to take into account new scientific evidence in favour of restricting the use of these insecticides as plant protection products. According to the Austrian Ombudsman Board, observations from beekeepers, as well as new scientific evidence, suggest that certain neonicotinoids have led to increased bee mortality in recent years. The EC asked the European Food Standards Authority (EFSA) Panel on Plant Protection Products to give a Scientific Opinion. In a Press Release on 1st June 2012, the EFSA conclusions were that for the research on bees and bumblebees, the concentrations used by the authors were too high to be “field realistic” and that the experiments should be repeated. However, the EFSA scientists, in their calculations, had failed to take into account evidence of contamination of water shown by New York State (NYS) Department of Environmental Conservation. This state (alone in the US) demanded monitoring because it is protective of the aquifers in Nassau and Suffolk Counties. As early as 1996 they had been concerned about the problem of persistence. In 2003, high levels of imidacloprid found in clusters of private wells down gradient of farms (one contained 6 ppb imidacloprid), at a golf course monitoring well and at monitoring wells near trees that had been treated with imidacloprid injection. As a result NYS never registered clothianidin and has severely restricted the use of imidacloprid and thiamethoxam. California Department of Pesticide Registration found residues of imidacloprid in treated plants in 2008 and Krupke et al. in a study of clothianidin and thiamethoxam in maize fields in 2012 found pesticide residues in soil, in dead bees, in wild flowers (dandelions), in pollen used to feed queens in the hive and in fields that had not be used for 2 years.

Henry et al. 2012 showed that nonlethal exposure of honey bees to thiamethoxam causes high mortality due to homing failure at levels that could put a colony at risk of collapse. Simulated exposure events on free-ranging foragers labelled with a radio-frequency identification tag suggest that homing is impaired by thiamethoxam intoxication. (On 29th June the French government has confirmed a ban on thiamethoxam-treated oilseed rape. They will be pressing ahead with a ban on Cruiser OSR, manufactured by Swiss agrochemical giant Syngenta, however, the ban only covers the Cruiser seed treatment, not Cruiser used for maize and rapeseed spraying.

Whitehorn et al. 2012 exposed colonies of the bumble bee Bombus terrestris in the laboratory to field-realistic levels of the neonicotinoid imidacloprid, and allowed them to develop naturally under field conditions. Treated colonies had a significantly reduced growth rate and suffered an 85% reduction in production of new queens compared with control colonies. Given the scale of use of neonicotinoids, the authors suggested that neonicotinoid insecticides may be having a considerable negative impact on wild bumble bee populations across the developed world. When exposed to these insecticides, only 15% of the mated queens survive the winter to start new colonies. This is already happening around the world. A reduction of 85% in the production of new queens accounts for the massive declines (and some extinctions) reported in the US and Canada from the late 1990s onwards.

In Regulation (EC) no 1107/2009 of the European Parliament concerning the placing of plant protection products on the market, Annex II, Criteria for approval, page 43, it states that a plant protection product should not be persistent in the environment. The persistence criterion is fulfilled where the half-life in soil is higher than 120 days. “Assessment of persistency in the environment shall be based on available half-life data collected under appropriate conditions, which shall be described by the applicant.” Registration documents confirm that imidacloprid, clothianidin (and presumably thiamethoxam which is broken down into clothianidin) are persistent in the environment and, according to EC laws, should never have been registered.

How can they be registered when scientists have reported all of these adverse effects? In the US and Europe, the Registration Divisions can over-rule scientists. They have a let-out clause in favour of economic factors and farmers. The recent analysis by the EFSA and sent to the European Commission rejected the findings of the new bee research. “The final decision on protection goals needs to be taken by risk managers. There is a trade-off between plant protection and protecting the ecosystem services, pollination, hive products and biodiversity. From a farmer’s point of view plant protection may be more important than hive products.”

It is evident that human health and the environment take second place to economics.

In the face of all this, why is it that major conservation NGOs are not demanding that neonicotinoids are banned on the basis of the precautionary principle.

 

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33 Replies to “Guest blog – Are neonicotinoid pesticides responsible for the demise of bees and other wildlife? – by Rosemary Mason and Derek Thomas”

  1. Very glad to see this article, thanks all. What should we do? A united, recognisable campaign surely is required for purple to get behind. Is there one already? Keen to get behind it!

    1. Jo – FoE and Buglife are probably most active on this subject. Perhaps they will comment here.

  2. Buglife is indeed asking for neonicotinoids to be banned under the precautionary principle.

    He have been asking for a ban ever since 2009 when we published our seminal review of the science “The impact of neonicotinoid insecticides on bumblebees, Honey bees and other non target invertebrates” (Kindemba 2009). http://www.buglife.org.uk/Resources/Buglife/revised%20neonics%20report.pdf

    Bees, hoverflies, butterflies and moths are valued animals. Without their free pollination services £510 million worth of UK crops would fail, as would most wild flowers.

    Seed drills pump out clouds of toxic neonicotinoid laden dust which kill bees – recent research proves drill modifications supposed to reduce collateral damage on non-target animals are ineffective. The toxins leach through the soil killing earthworms, and levels in guttation fluid from the foliage are high enough to kill bees which drink it.

    Neonicotinoid-tainted nectar and pollen, like that produced by treated plants, reduces honeybee activity and reproduction, and slashes by 85 per cent the number of next year’s queens emerging from bumblebee hives.

    Meanwhile, published field studies heralded as proving neonicotinoids have no impact on bees have been shown to be too statistically weak to detect the effects which have been observed in laboratories around the world.

    The case is not 100% clear cut or decided, there are unpublished studies that show limited impacts of the Neonicotinoids in the field on Honeybees.

    However, it is now widely acknowledged by UK and EU authorities that the pesticide regulation regime has been too relaxed, Honeybees are a poor surrogate for wild pollinators such as bumblebees, moths and solitary bees. The Varroa mite of course never touches these wild species so can’t be the cause of declines.

    New pesticides are pouring onto the market, the screws must be tightened to ensure that in the future pollinator damaging chemicals are never spread all over our countryside.

    Populations of bumblebees, moths, butterflies and hoverflies are declining; we must save them.

    The Italian, German, French and Slovenian governments have already introduced bans of different forms. How long will it take our Government to step in and ban neonicotinoids?

    To support Buglife’s work go to – http://www.buglife.org.uk/joinus/Joinbuglife.htm

    1. Ironic or plain scandalous? that the EU and member states pour agri-environment / public money into farming for biodiversity, and at the same time continue to allow neonicotinoids to constrain the wildlife gains? We urgently need to at least trial a ban somewhere meaningful in the UK in order to monitor the response (in addition tightening up the approvals process etc).

  3. I spent some time reading up on this after reading the buglife website in 2011 which included

    “In the leaked memo the EPA scientists state that “information from standard tests and field studies, as well as incident reports involving other neonicotinoids insecticides (e.g., imidacloprid) suggest the potential for long-term toxic risk to honey bees and other beneficial insects”

    There is a page

    http://www.buglife.org.uk/conservation/campaigns/Protect+wildlife+from+pesticide+impacts this page contains a link to a petition http://www.gopetition.com/petitions/protect-wildlife-from-pesticide-impacts.html

    Regards

    Mike

  4. Thanks for the blog. It’s very timely because we’re seeing the UK Government’s National Bee Unit (NBU) and Food and Environment Research (FERA) to discuss this and other causes of bee and pollinator decline.

    In May I invited FERA and the NBU (plus Buglife, Defra’s Chief Scientist, the British Beekeepers Association, Small Blue Marble and many others) to the launch of our comprehensive report into the topic.

    I’d asked Simon Potts and Stuart Roberts and their team at the University of Reading to pull all of the evidence together so that we can pinpointing what needs to happen as part of a UK Bee Action Plan David Cameron now needs to draw up – and fast.

    The report – see http://www.foe.co.uk/beesreport – shows a rise in chemical pesticide use in the 5 years to 2010 including a 295 per cent rise in use if insectides on British strawberries and 78 per cent rise in herbicides on oil seed crops (mainly oil seed rape).

    No one can say what the true effect of these (rising) applications is because they have not been tested for on wild – not just managed – bees and other pollinators.

    Under these circumstances it is entiirely proper and within its power for the UK Government to use the under-used Precautionary Principle – and suspend use of neonics.

    It can then also carry out full and tranparent research into the wider effects of chemicals on pollinators as this is now more than a matter of company secrets and commercial confidentiality.

    The University of Reading report concludes on page 31:

    “Perhaps the greatest shortcoming identified by this study is the failure of government to fully recognise the importance and conservation needs of bees across the country… policy remains largely negligent of them.”

  5. Would you lie to talk about this on our radio programme ENVIRO?

    let me know asasp

    Britt du Fournet

    reasercher

    nearfm

    coolock

  6. Mark, once again you are to be congratulated for a well written and informative piece of journalism. Sadly politics, money, power and greed are fuelling the extinction of much of the world’s fauna and flora today. It seems common sense strategies which would enhance the healthy biodiversity of our planet are being almost completely ignored because of these issues.

  7. Not wishing to detract from any of foregoing – it would make a better case, when quoting statistics, to provide some baseline units in addition to percentage figures, or a guide to the proportion of all crops so treated.

    For instance, it is not clear above whether the use of herbicides on oilseeds 2005-10 rose by 78% weight of active ingredient per hectare where pesticide was used, or whether the proportion of all oilseed crops treated rose by 78%. Or from what amount the 300% (no spurious accuracy please) increase in stawberry insecticides increased from – 300% of what may be very little is still very little.

    Statistics are frequently used to indicate trends like “Over the duration of the survey the active ingredient applied per hectare fell from 100grams/ha to 10grams/ha – a tenfold reduction”. This is misleading if the “new improved” a.i. is a thousandfold more efficacious against the target organism. Let’s leave the cherry-picking and distortions to others – and use transparent and unequivocal reporting to present “our” cases. I am not casting nasturtiums at the previous commenters, btw.

    1. I think Filbert Cobb is referring to Paul Da Zylva’s comments, not to our original guest blog. However, Mr Cobb is at liberty to verify the facts himself on the Defra website.
      http://pusstats.csl.gov.uk/ .
      Rosemary Mason

      1. “I think Filbert Cobb is referring to Paul Da Zylva’s comments”

        You are correct.

  8. Thanks for the article, it is crazy that pesticides are being given licences before detailed testing. Made me write the following to my local supermarket –

    Dear Mr Coop

    I am a huge supporter of your bee campaign and want to congratulate you.

    I read this morning the following blog – https://markavery.info/2012/07/09/guest-blog-neonicotinoid-pesticides-responsible-demise-bees-wildlife-rosemary-mason-derek-thomas/#comments.

    Having read your position on neonicotinoids will you now consider putting permanent bans in place on all coop products? In addition will you be putting any pressure on your suppliers to do the same?

    Since the evidence on this is becoming clearer will you consider campaigning Government to bring in similar bans to those that were introduced in France?

    I notice that you have a petition calling for research into this issue and you should be commended for funding research too.

    However, do you not consider that this goes against the precautionary principle and restrictions should be brought in then lifted if they are proved not to have an impact?

  9. Brilliant thought provoking article.

    As with climatic change, I would follow the ”precautionary principle” – ignore at our peril!!!!

  10. Excellent, if depressing, article. Sad to think that the ravages of DDT and other extreme poisons seem to have been completely forgotten. As an historian, it has always amazed me that we humans simply do not seem to able or to want to learn from past mistakes.

  11. An excellent post. My specific area of interest is the honeybee, but it’s obvious that all invertebrates are under threat. As they are the base of the biological pyramid, it won’t be long before steps further up the ziggurat start to fail.
    Chilling.

  12. To Filbert Cobb,

    I mentioned the figures in brief because this is a blog rather than a scientific paper – the report I mentioned – and gave a link to – provides the detail you’re looking for.

    Paul De Zylva

  13. What a really fantastic article by Rosemary and Derek. It’s great to have the issues so clearly spelled out. I’m with Jo (2nd comment) we have the facts? Now what can we do together to address this??!

    Thanks for organising such a stimulating guest blog Mark!

  14. Just a small correction, if I may, to this otherwise excellent article.

    Friends of the Bees (www.friendsofthebees.org) is not intended to replace or even compete with the BBKA. It is a campaigning network of bee keepers and bee ‘supporters’ and others who simply understand how vital bees and other pollinators are to flowering plants and thus to the health and well-being of the natural world.

    We encourage people to create ‘Bee-Friendly Zones’ on any land over which they have control, from a window-box to a country estate, simply by excluding all pesticides and herbicides and planting and/or encouraging wild species of flowering plants. By this simple means, almost anybody – including children – can help restore the ecosystems of some of our most important species.

  15. Mark,
    My wife wrote to our MP (John Glen) pointing him to your Guest Blog (which I thought was fascinating and worrying in equal measure). The subject was new to him but he gave a reasonably balanced response as follows:

    Dear Annie
    Thanks for forwarding the attached article – it was very interesting. I can tell you that DEFRA is currently reviewing the regulatory information on neonicotinoids alongside recent academic literature to try and gain a fuller insight into the potential impact of these pesticides, particularly on bees. This includes some information, albeit limited, on why the authorisation is being withdrawn in France.
    We also established the independent scientific Advisory Committee on pesticides, and the project will be overseen by DEFRA’s Chief Scientific Adviser. The regulatory system for pesticides is comprehensive and is constantly updated to ensure that it continues to protect people and the environment.
    There has been a lot of academic activity around bees this year, and the risk assessment has been an area of active development. Since its establishment, the Food and Environment Research Agency’s National Bee Unit has not been able to conclusively link neonicotinoids with cases of bee mortality, but some academic studies across the UK and EU disagree with their findings. The general consensus is that the most important factor in the mortality of colonies is deformed wing virus.
    In addition to this, 44 bee death incidents has been investigated since 2009 – 10 of these contained neonicotinoid residues, but other pesticides were also found in eight of those ten. Only two even indicated that pesticides had a role in the death of the bees.
    The HSE Chemicals Regulation Directorate is responsible for the regulation of pesticides in the UK, and they attended a European Commission meeting to discuss the EU position on them, and this included presentations from the European Food Safety Authority – whose statement we will take into account in influencing future policy making.
    I have attached a note from the House of Commons Library on this issue you may find interesting. This is the first time it has crossed my radar, but I am confident the Government is on to it. If you feel otherwise, do not hesitate to let me know and I will look into it for you.
    Very best
    John

    Of course it all depends on what vested interests are at influence in the system. Not sure if you will have seen the HofC note – it is entitled ‘Bees and their Problems’ dated 13 July 2012.

    Hope this is of interest.

    David.

  16. When we started using Gaucho (imidacloprid) in our sugar beet crops in the 90’s the view was that it was better for the environment than existing control measures, which involved applying successive pyrethroid sprays to crops. By applying the insecticide to the seed, it was only the crop pest that fed on the crop plant that was being targetted, rather than the wider environment. It does appear however that this is also the downfall of neonicotinoids, as they are persisting in the pollen and nectar of crop plants that bees feed on.

    It is worth noting that sugar beet doesn’t flower before it is harvested, so bees cannot be affected in this way. They could however be affected if residues in soil are taken up by flowering weeds, and this I think is where the problem lies. Winter wheat crops treated with clothianidin also won’t be fed on by bees, but again it is the soil residue problem that needs to be looked at.

    If indeed these pesticides are persisting long enough to do damage to bees and the environment then they do need banning if control measures cannot prevent it.

  17. This move to get a ban on neonicotinoids looks more political activism masquerading as science.
    From the International Union for the Conservation of Nature: “We would try to pull together some major names in the scientific world to be authors of this paper. If we are successful in getting these two papers published, there will be enormous impact, and a campaign led by WWF etc could be launched right away. It will be much harder for politicians to ignore a research paper and a Policy Forum paper in Science. The most urgent thing is to obtain the necessary policy change to have these pesticides banned, not to start a campaign.

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