bee research

Research FAQs

1. What are the basic numbers?

2. Why are bees so important?

3. Are bees more important for their honey or for their pollination?

4. What is a pesticide seed treatment? How do neonicotinoids work and what benefits do they bring?

5. Which products are suspected of causing the disappearance of bees? Does Syngenta make any of them?

6. So what is the connection between neonicotinoids and bee losses?

7. What basically do the experts say are the causes of bee losses, in a nutshell?

8. Explain each of these causes in a quick summary in order of significance

9. How can you ensure that seeds treated with neonicotinoids do not pose a risk to honey bees?

10. How can you make sure that users and operators will use the products safely and properly in the environment?

11. How can a bee-friendly agriculture be achieved, according to Syngenta?

12. There’s no smoke without fire. Do you accept that your products harm bees?

13. What is Syngenta doing to protect bees in the environment?

14. What can Europe’s beekeepers do about the bee health problem?

15. Surely banning neonicotinoids would be worth doing as it would at least remove one of the possible causes of bee losses?

16. How am I supposed to distinguish between good and bad research?Isn’t all research biased, one way or another?

17. Why has the French Government banned the seed treatment Cruiser® OSR?

Bee health

The interaction between agriculture and bees is a natural symbiosis. Bees feed on pollen and nectar, while many crops need bees for pollination. But the habitat is not a natural one and does not provide optimal living conditions for bees.

In the past few years, Europe has experienced a worrying decline in the health of managed honey bees which has resulted in damage to colonies and populations. Many different possible causes have been suggested and promoted.

The overall scientific consensus is that the health decline is caused by many different factors acting together, but principal among them are the parasitic mite Varroa, viruses carried by mites, a new intestinal gut pathogen Nosema ceranae, and the loss of suitable habitats (for wild bees) and low quality nutrition.

Often the losses have been blamed on pesticide seed treatments (for example the neonicotinoids-based insecticides) used on the crops growing near to where bees forage.

It is important that a full picture of the complete issue is transparently available to everyone concerned. The debate on bee health produces more questions than answers and although this is not the definitive word on the subject, we hope that this booklet will help to provide straight and uncomplicated answers to some of the most common questions that people ask about the disappearance of bees, and the application of pesticides in Europe.

The honey bee is a unique and vital insect in our world and all those involved in agriculture need to work together to establish and understand the causes of its plight and to take decisive action to ensure its survival.

1. What are the basic numbers?

There are approximately 20,000 different species of bees in the world and around 2,500 in Europe. Most are solitary bees and only a few species actually form colonies. There are around 65 million hives worldwide.

Only one species in Europe, the European Honey Bee (Apis mellifera) is managed for honey production.

The number of bee keepers in Europe is estimated at 700,000, keeping around 15 million hives. 97 percent of these beekeepers are amateur apiarists, and they account for around 10 million hives.

The last few decades have seen a decrease in the number of people involved in the maintenance of bee colonies in some parts of Europe and the United States. On the other hand, there has also been a big increase of honeybee colonies in Asia, Africa and South America.

The total number of honey bee colonies globally has increased by approximately 45% since 1969 according to FAO data. Insecticides are currently used to protect crops in every continent of the world.

2. Why are bees so important?

Bees are vitally important to the sustainability of European agriculture because they pollinate around 80% of our crops, adding some €20 billion annually in economic value.

Without pollination by bees, farmers, food processors, retailers and even crop protection and seed companies would find it hard to develop and grow their businesses. Consumers would not be able to enjoy locally produced foods, especially fruit, which we all now take for granted.

As bees fly from plant to plant gathering pollen and nectar, the pollen they pick up at one plant brushes off on the next, completing the bees’ reproductive role in cross-pollination.

At least one third of the human food supply from crops and plants depends on insect pollination, most of which is done by bees, especially the domesticated European honey bee.

3. Are bees more important for their honey or for their pollination?

The direct value of honey produced in the EU is estimated at about €500 million, while the annual value of insect pollination for European agriculture has been estimated to be around €20 billion, and €153 billion worldwide (Gallai et al, 2009). The value of pollination of wild plants and its contribution to biodiversity is not quantified.

Even these bare statistics do not properly explain the crucial importance of the honey bee in food production, since without pollination several types of fruits, seeds and vegetables could not be produced in quantity at all (apples, almonds, blueberries, peaches, nuts etc.) and although some staple foods do not depend on pollinators (wheat, grapes, rice and corn), pollination by bees is significant in the production of soybeans, cotton and oranges, and of course, in flowers and flowering trees. Some 80% of all European crops are pollinated.

The role of pollination is now so important that many organizations, including beekeepers, now breed bees specifically to offer contract pollination services, particularly in the United States. In many cases, the bees are collected, driven and even flown across thousands of miles to pollinate crops in the absence of enough wild bees to do the job.

Without pollination several types of fruits, seeds and vegetables could not be produced at all.

4. What is a pesticide seed treatment? How do neonicotinoids work and what benefits do they bring?

Pesticide seed treatment is perhaps one of the most advanced forms of crop protection chemistry. It is also one of the most environmentally friendly ways of applying pesticides.

The chemical is applied to the seed as a coating prior to planting. This enables the plant to defend itself against pests that feed directly on the plant. These pests would otherwise destroy the crop, wasting huge amounts of soil and water.

Neonicotinoid seed treatment is an environmentally safe insecticide. It provides instant, early-season, broad-spectrum pest control, improving plant vigor and crop yield. Seeds treated with neonicotinoids include corn, cotton, cereals, sugar beet, oilseed rape (canola), vegetables, and rice.

The insecticide is absorbed and distributed within the plant as it grows and hence only affects insects which feed on the growing plant. It also controls pests in the zone around the crops’ root system. Neonicotinoids have proven to be extremely popular with farmers wherever they have been sold. They reduce the number of pesticide applications and decrease the amount of pesticide used per hectare.

Pests such as the wireworm can destroy an entire cornfield single-handedly. In 2007, maize farmers in France lost approximately €250 million of crop harvest because a sufficiently effective solution was not available. Cruiser® OSR, which the French Government has now banned, has been used for many years on millions of hectares of oilseed rape across Europe without damage to the environment or to bees. It has also protected the crop against pests that would destroy up to 30% of the yield, and in France added around €100 million of value for oilseed rape farmers and the food chain and up to €1 billion across the EU.

5. Which products are suspected of causing the disappearance of bees? Does Syngenta make any of them?

The group of chemicals that is suspected of causing bee losses is known as neonicotinoids.

Neonicotinoids are a class of insecticide developed largely because the previously used insecticides were seen as too toxic for regular use.

There are three active ingredients used in the neonicotinoids group for seed treatment in Europe: Imidacloprid, Clothianidin and Thiamethoxam (TMX). The last of these is made by Syngenta.

TMX can be sprayed on leaves or applied to the soil, as well as being used as a seed coating to protect plants. Syngenta uses TMX to coat corn, cotton, lettuce, cereals, sugar beet, oilseed rape sunflower, and rice seeds. As the plant grows, TMX is gradually absorbed within the plant, protecting it from harmful pests and requiring fewer pesticide applications. When used correctly, these application methods target the pesticide at insects which feed on the plant (ie pests) but limit exposure and minimize risks to all other insects including bees.

6. So what is the connection between neonicotinoids and bee losses?

The allegation that neonicotinoids-based pesticides are inherently damaging to bee colonies or populations is not true. For example, evidence from Scotland shows that there is poor bee health even though there is very low neonicotinoid pesticide use. However, there is a high incidence of the Varroa mite in Scotland which may better explain the poor bee health.

In France, the level of colony losses is similar in mountainous areas to that on agricultural land.

In Australia, neonicotinoid-based seed treatments are used widely but there have been no reports of significant declines in the health of bees. Indeed, many Australian beekeepers have exploited this by sending their bees to countries such as the United States in order to provide contract pollination services. Not surprisingly, the Government of Australia is keen to protect bee health and its prime goal is to concentrate on policies to prevent the Varroa from invading Australia and to have emergency plans for eradicating the Varroa mite should it eventually arrive there.

In Madagascar neonicotinoids are virtually unused but beekeepers have been suffering substantial bee losses since the recent introduction of the Varroa mite in 2009.

In Switzerland, there have been reports of significant declines in bee health in upland areas of the country. Neonicotinoids are not used in these areas and cannot be held responsible. The Swiss Government reported in the summer of 2012 that pesticides were not the cause of declines in bee health.

South Africa and Brazil both use neonicotinoid-based pesticides widely, yet both countries have good bee health. However, both of these countries have low incidences of the Varroa mite due to the increased presence of the Africanized honey bee which is able to delouse itself.

There is therefore no direct correlation between neonicotinoids use and poor bee health, although a correlation can be drawn between bee losses and the presence of the Varroa mite.

7. What do the experts say are the causes of bee losses?

Most experts argue that bee health is likely to be affected by several different factors, especially when acting together. These include the following:

  • Pests and diseases, in particular the Varroa destructor mites and the viruses they carry, and the Nosema ceranae gut parasite, which have been found in hives throughout Europe.
  • Poor nutrition in some areas due to a lack of quantity, availability and quality of nectar and pollen in areas with limited biodiversity, many municipal gardens and large areas planted with just one crop, known as monocultures.
  • Some beekeepers’ lack of knowledge of professional and hygienic hive management and good beekeeping practices, as well as a lack of veterinary solutions.
  • Pesticides mistakenly misused by farmers, especially when clearly shown product use recommendations are not followed.
  • Many wild bees are dependent on special habitats and wild plants, and suffer in particular from habitat loss and fragmentation, also due to urbanization and monocultures.
  • Genetic uniformity of the majority of honeybees, leading to weakened resistance to pests and diseases.
  • Stress caused by commercial transportation over long distances to pollinate particular seasonal crops and due to the intensification of beekeeping.
  • The unusual weather of the past few decades.

The scientific consensus from ongoing monitoring projects suggests that while there is no single factor, the parasitic mite Varroa destructor is the main and possibly the common factor involved in causing honey bee colony decline in Europe. Nevertheless, efforts to find clearer solutions continue.

Of all the suggested mechanisms of honey bee loss, virus infection brought in by mite infestation is a major cause of the decline.

8. Explain each of these causes in a quick summary in order of significance

Mites, viruses and diseases, particularly the Varroa destructor mites and the diseases they carry, have been found in hives throughout Europe. Most scientists agree that the Varroa mite, which was first seen in European hives in the 1980s, is the common factor involved in causing bee colony decline in Europe.

The continuing presence of the Varroa mite in European hives may indicate that beekeepers need much more assistance to help them fight infestations. A minority of beekeepers also lack detailed knowledge of professional and hygienic hive management and good beekeeping practices. For too long, beekeeping has been an underrated, undervalued and under-explained function, and this needs to change.

However, in some areas poor nutrition in bees is due largely to a lack of quantity, availability and quality of nectar and pollen in areas with limited biodiversity, and large areas planted with just one crop, known as monocultures. Many types of wild bees (which mostly live alone) are dependent upon particular habitats and wild plants, and suffer disproportionately from habitat and biodiversity reduction.

Other factors include the impact of neonicotinoid-based pesticides mistakenly misused by farmers, or the rare failure by them properly to follow clear product use recommendations. Honey bees are also inbred and domesticated, which can lead to a progressive weakening in their resistance to pests and diseases.

Although less prevalent in Europe than in the USA, it is well known that significant stress is caused to bees by being transported over long distances to pollinate particular seasonal crops.

Finally, the variability and the inconsistency of seasonal weather patterns due to global warming has often been ascribed as a key factor in bee health, especially in respect of their survival rates over the winter. Climatic factors may also explain the arrival in recent years of new pests and predators that were not previously a factor.

9. How can you ensure that seeds treated with neonicotinoids do not pose a risk to honey bees?

In the manufacturing process, Syngenta strives for the highest possible seed treatment quality assurance because badly coated seeds can cause the active ingredient to be loosened from the seed through abrasion as dust when the seeds are agitated, for example during the drilling.

The drift of this dust to nearby crops and plant borders could in some circumstances be harmful to bees and other pollinators. Syngenta and some other producers have introduced dust limits for seed drilling. Several countries in Europe have introduced dust limits for treated seeds and compulsory use of deflectors during drilling to reduce the risk of dust to bees.

To ensure the safety of seed treatments outside the controlled settings of laboratory, manufacturing and field tests, Syngenta works closely with its customers to make sure that measures to reduce dust levels are applied throughout the environmental stewardship and the seed care value chain.

Syngenta research has found no risk to bee colonies exposed to neonicotinoid-treated crops, particularly oilseed rape and maize, even when exposed for several years. The studies included exposure of bees to nectar, pollen and guttation water from treated crops, and dust during drilling.

In summary, comprehensive safety research has shown that, when produced and used correctly, neonicotinoids do not affect honey bee colony health.

10. How can you make sure that users and operators will use the products safely and properly in the environment?

We are determined to provide our customers and growers with awareness and appropriate information on best practice for working with our products – enabling them to run safe operations. However, Syngenta does rely on farmers and growers using the products as instructed. With the exception of just a very few cases of misuse and accidental use, they do.

Examples of activities in Europe include seed treatment site visits and training, grower information - for example during field days, cooperation with seed associations on voluntary seed treatment quality certification schemes, web-based training materials and thorough training in sustainable agriculture and safe product use.

Stewardship is a key part of the Syngenta culture and is a critical component of sustainable agriculture. This means that Syngenta will act accountably and responsibly throughout the life cycle of every product we bring to market.

Our approach to manufacturing and sales coupled with our partnerships with farmers, growers, NGOs, government agencies, and organizations in stewardship and environmental programs are expressed through award-winning and industry-leading programs.

11. How can bee-friendly agriculture be achieved, according to Syngenta?

Today, most stakeholders talk about sustainable agriculture in economic, social and environmental terms, but not so long ago these terms appeared to be mutually exclusive.

Most stakeholders are now coming together to consider the real and sometimes difficult decisions that need to be taken to ensure that the planet can produce enough food for its growing population but also to grow it in a way that is sustainable and responsible as well as productive and profitable.

The Syngenta approach to sustainable agriculture involves working in partnership with stakeholders to:

  • conduct research on crop protection practices that target pests even more precisely
  • maintain a high level of safety to people and the environment
  • build knowledge and skills in integrated farming, crop and pest management techniques and safe and sustainable use of crop protection products
  • encourage the adoption of sustainable principles and practices, as part of integrated farming systems
  • identify and disseminate best management practices, providing alternatives to ensure grower options and promote acceptance
  • take into account the social, economic, and environmental dimensions of all agricultural practices.

Syngenta believes that seed treatment is a perfect example of the type of innovation that can help to close the productivity gap, and encourage sustainable intensive farming. Seed treatment reduces the number of pesticide applications and decreases the amount of pesticide used per hectare.

In 2007, for instance, when seed protection was not used on maize in France, an average of 600 grams of active ingredient per hectare treated was applied to the soil to fight pests. When using treated seeds, the active ingredient used was less than 70 grams per hectare (the registered rate for TMX is 69.7g/ha) protected, a tenfold reduction.

Seed treatment is a perfect example of the type of innovation that can help to close the productivity gap and encourage sustainable intensive agriculture.

12. There’s no smoke without fire. Do you accept that your products harm bees?

There has been a lot of publicity and media coverage about the presumed impact of neonicotinoids on bees. But while some of the publicity may suggest that neonicotinoid products are responsible for some bee losses, the only way to investigate this properly is to examine the science.

Neonicotinoids are insecticides and as such are designed to kill insects. However, they have been extensively tested and have gone through a thorough scientific approval process with government authorities. Their application is designed so that they present a minimal risk to insects except those pests for which they are specifically targeted.

When used properly, at the right time, and according to the instructions on the label, products made from neonicotinoids do not present a risk to honeybee colonies. If Syngenta thought that its neonicotinoid products, properly used, were responsible for the decline in honey bee health we would act accordingly. Our business depends on bees and upon bee health; therefore we have a vested interest in reversing the decline.

The registration of all pesticides relies on a strict set of rules relating to risk assessment and information which defines, for each use, conditions that ensure that the highest possible safety conditions are met before any products are placed on the market.

We are therefore satisfied that our products correctly used have not damaged any bee populations despite having been used on millions of hectares of European crops over the past ten years.

When used properly, at the right time, and according to the instructions on the label, products made from neonicotinoids do not present a risk to honey bee colonies.

13. What is Syngenta doing to protect bees in the environment?

Syngenta is working with beekeepers and the relevant authorities to tackle the causes of bee deaths, and testing a range of solutions to combat the diseases affecting bees, including new biological and chemical control agents to fight the parasitic mites such as Varroa destructor and the fungal parasite Nosema ceranae, that are found in a large majority of beehives in Europe.

There is also a pressing need to alleviate the problem of food scarcity for bees and other pollinators. To this end Syngenta launched Operation Bumble Bee in the UK in 2005. This involved planting field borders with combinations of nectar/pollen producing species that flower at different times of the year. Within three years the project had increased bee populations by several times over and helped to regenerate rare species, previously close to extinction. Other pollinating insects increased tenfold, and the butterfly population twelvefold.

Syngenta extended this work to the rest of Europe in 2008 by launching Operation Pollinator, which encourages bee-friendly farming and helps to ensure the availability of flowering plants at times when agricultural crops do not offer a sufficient supply of pollen and nectar for bees.

Another avenue of research is to develop new strains of bees with stronger resistance to diseases and parasites. Independent researchers in Europe are developing ways to breed “hygienic bees” that unlike most commercial bees, clear out infected young and can resist Varroa mites. Other research is under way on the causes of bee decline and epidemiological approaches are also being investigated.

14. What can Europe’s beekeepers do about the bee health problem?

We believe that beekeepers play a vitally important role. They should be supported by clear guidance on bee health management, and with better information on hygiene practices to reduce hive infections and diseases. Beekeepers have not had enough recognition from government and regulatory authorities in recognizing their difficult economic situation and the vital role they perform.

New beekeeping techniques, agricultural demands and improved knowledge have resulted in higher quality and quantity of honey yields and improved bee health in many areas. Nevertheless beekeeping is still today overwhelmingly an amateur occupation across Europe, and is often no more than a hobby. Only 3% of beekeepers are professional apiarists. This state of affairs contrasts starkly with the public estimation of the critical economic importance of bee pollination in agriculture.

There is no significant animal health legislation anywhere in the world that requires bee keepers to maintain high standards of health and safety. This is in marked contrast to the raft of legislation with which others involved in husbandry, for example, owners of cattle and growers of fruit, have to comply. In Germany, where the national practice is to clean out the hives regularly, there are practically no incidences of bee losses.

The threat and damage to bee colonies wrought by the parasitic mite Varroa destructor has been present for well over thirty years, and despite well publicized lobbying by beekeepers at national and European level, the impact of the Varroa mite and the honeybee diseases and viruses they carry has not in fact reduced but increased.

15. Surely banning neonicotinoids would be worth doing as it would at least remove one of the possible causes of bee losses?

Since we do not believe pesticides cause bee losses, banning them will not make any difference to bee health. This is also the view of the Swiss and other Governments.

Banning neonicotinoids on maize, sunflower, and growing oilseed rape without neonicotinoids in France between 2004 and 2008 did not improve the situation of beekeeping in France and did not stop heavy bee losses during that time.

Banning neonicotinoids might remove one of the possible causes of bee losses in the sense that accidental misuse by farmers of neonicotinoids-based seed treatments could not then occur if the product was not available.

However, such an action will not stop the bee losses, since other factors will continue to apply and exert their impact individually and collectively. Non-neonicotinoids-based pesticides would also still be available, especially the older formulations, which would not be without risk to bees.

Perhaps even more serious than this is that farmers will be denied access to one of the safest, most effective and sustainable options in producing healthy, nutritious and safe food. Seed treatment is a revolutionary technology and an environmentally more friendly and more sustainable way of using particular pesticides, as the amounts used can be very small and are targeted on the pests.

Banning one class of pesticides will therefore not make a difference to bee health.

16. How am I supposed to distinguish between good and bad research? Isn’t all research biased, one way or another?

This is a research area in which politics and special interests have not necessarily played a helpful or positive role in Europe. From agribusinesses to farmers and beekeepers to NGOs, all participants have a major stake in the outcome of the debate.

Nevertheless it does not mean that research directly or indirectly paid for by any of these groups or interests is discredited just because of the source of its funding. Some of this research is important and useful.

On the other hand, research that does not follow internationally accepted scientific guidelines, disciplines and conditions, or which cannot be checked, tested or the results properly reproduced, are not helpful in the search for the solution. Unfortunately, some of this type of research does seem to have influenced national and international political decision-making. Worse still, the mistaken adoption of the conclusions of this type of research means that the real cause of the decline in bee health is disguised.

In addition, the published research often does not reflect the reporting as the media need to exaggerate aspects of the story in order to get it better noticed. It is all too often the interpretation, summary or extrapolation and not the original research that is made memorable. Academic research is, perhaps inevitably, targeted on discovering uncertainty and not resolution.

The mistaken adoption of the conclusions of some research means that the real cause of the decline in bee health is  often disguised.

17. Why has the French Government banned the seed treatment Cruiser® OSR?

A good example of research being misused was that upon which the French government drew to announce the suspension of the registration of Cruiser® OSR for use on oilseed rape. The research was carried out by Mickaël Henry and other researchers in conjunction with the French National Institute of Agronomic Research (INRA) and showed that bees exposed to large concentrations of pollen and nectar (30 times higher than bees would ever encounter in the field) became disoriented and had difficulties locating their hives.

Although the research was innovative in its use of tracking devices to record the movements of bees, the dose rate was so high and the period of exposure so short that it would have been equivalent to a person consuming 5 bottles of wine in a day instead of just a glass. Equally, if a person took half a bottle of aspirins in a day instead of just two pills their health would – not surprisingly – be in real danger.

The European Food Safety Authority (EFSA) questioned the research, noting that there were:

"Several uncertainties regarding these results, therefore, they should be considered with caution. In particular, bees consumed the total amount of active substance within a relatively short period and not administered over a longer period ie a day. Depending on the substance properties and how fast the substance can be metabolised by the bees, this method of exposure could have led to more severe effects than what may occur when bees are foraging".

Several independent scientific experts from around Europe have confirmed these conclusions. In his review of the Henry study, Dr. James Cresswell at Exeter University, argued that his results suggest: “that dietary thiamethoxam, (eg TMX on pollen and nectar from treated crops) would not precipitate a collapse in healthy colonies”.

He also said that pesticide regulators should be cautious in using the Henry model for risk assessment purposes. Mickaël Henry himself agreed that more research would need to be done on his model before it could be used in this way.

So far there has been little or no support amongst EU member states for the position of the French Government on Cruiser® OSR.

Moreover, the decision is likely to be costly as well as ineffective. Bee losses did not decline in France between 2004 and 2008, when neonicotinoids were last suspended. French oilseed rape growers risk making a massive financial loss after being denied access to a technology used safely on millions of hectares of crop for the past 10 years without damaging bee health.

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