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Dossier: the pollinator crisis and new technology

  • Written by  Mark Rowe
  • Published in Wildlife
Dossier: the pollinator crisis and new technology
18 Jan
A tightening of restrictions on the insecticides known as neonicotinoids has brought hope that the decline in honey bees and wild pollinators can be reversed. Yet concerns are growing as to how new technology could radically change the landscape. Are we heading towards a world of ‘frankenbees’, in which gene-edited bees are resistant to pesticides and where only the rich can afford to pay for pollinated crops?

When is a ban not a ban? When, it seems, it applies to neonicotinoids. Amid much fanfare, the European Union last year expanded the restriction of three pesticides – clothianidin, imidacloprid and thiamethoxam, all of which act as nerve agents – to all field crops. The decision was taken in the face of growing evidence that the pesticides can harm domesticated honey bees as well as wild pollinators. This reinforced a moratorium dating back to 2013, which forbade their use in flowering crops that appeal to honey bees and other pollinating insects. Thiamethoxam has been shown in laboratory studies to dramatically reduce egg laying by queen bumblebees and all three neonicotinoids affect bees’ memory. By the end of 2018, thiamethoxam’s use in Europe was limited to indoor greenhouses.

This strengthening of the law was necessary because the 2013 ban did not confine the pesticides to history. The prohibition only applied to certain crops, such as oil seed rape and sugar beet. Continued use on some cereals was permitted and actually increased in the UK after the ban, according to the government’s own open-source website (geog.gr/peststats). 

The UK was not the only EU country in which neonicotinoid use continued. In Romania, farmers successfully lobbied against the ban on the grounds that they were suffering economic losses. ‘Bee keepers there are absolutely desperate about the state of losses,’ says Professor Noa Simon, scientific and technical advisor for both BeeLife (an association of European beekeepers) and CARI (the Belgian apiculture research institute). ‘It’s incredible that 20 years after concerns were first raised about neonicotinoids, these pesticides are still with us.’

Beyond European shores their use is even more striking. The three neonicotinoids in question remain the world’s most widely used pesticides. ‘The EU has the best regulation but it’s not perfect and outside the EU it is pretty much open season, with the exception of [the Canadian state of] Ontario,’ says Professor Dave Goulson, of the School of Life Sciences at the University of Sussex. In August 2018, the current US administration overturned a ban on neonicotinoids brought in under Barack Obama.


Honey bee shortages
According to a study covering 41 European countries the overall number of honey bee stocks has increased by seven per cent between 2005 and 2010 (to an estimated 13.4 million colonies with seven billion honey bees). Unfortunately, 15 countries have also experienced declines, ranging from four per cent in Slovenia to 47 per cent in Switzerland. At the same time, more biofuel crops (oilseed rape, sunflower and soybean) means increased demand for pollination. This map series demonstrates the link between density of honey bees and the number of colonies required to provide pollination services. The supply of honey bees relative to the national demand varies considerably between European countries. Of all countries included in the survey, the United Kingdom’s shortage of honey bees is only surpassed by Moldova.


The use of neonicotinoids as well as other pesticides, insecticides and herbicides has been closely associated with a decline in pollinators. Honey bee numbers in the US and UK have dropped by around 50 per cent in the last 25 years. More than half of UK rivers are more polluted than they should be and that, says Matt Shardlow, chief executive of conservation charity, Buglife, is down to neonicotinoids. Last summer, a vision of an insect armageddon emerged after a study of nature reserves across Germany found that the abundance of flying insects had plunged by three-quarters over the past 25 years. The scientists ruled out weather change in the reserves as a cause. While data on pesticide levels had not been collected, it was widely concluded that pesticides and destruction of wild areas were likely to be the main causes.

‘The drop of 76 per cent in 25 years was pretty terrifying,’ says Goulson, who was involved in the study. ‘The most plausible theory to explain it is the way in which the environment has changed. Nature reserves are now islands surrounded by the fairly hostile terrain of intensive agriculture. Our best guess is that if bees and other insects wander out of those reserves they are unlikely to survive the experience.’

Even with the partial ban on neonicotinoids, other pesticides and insecticides are still widely deployed. Across the EU, more than 500 pesticides are approved for use and regulation appears haphazard. ‘Even fungicides haven’t been well studied,’ says Goulson. ‘There’s a suggestion that fungicides may be even more harmful to bees than neonicotinoids. It’s not a huge leap to say they are playing a significant role in the decline of insects. Ultimately it’s a combination of this blizzard of pesticides and changes in habitat.’

The stakes are extraordinarily high. According to the UN’s Food and Agriculture Organization (FAO), 90 per cent of the world’s food supply comes from about 100 crop species, and 71 of those crops (especially fruits and vegetables) rely on bees for pollination. Around 270 species of wild bee do the bulk of this work.

Integrated Pest Managment
The concept of integrated pest management (IPM) is the default position of both the European Commission and the FAO. In essence, it asserts that, when it comes to pest control, pesticides are the tool of last resort and that natural pest control mechanisms should be deployed first. ‘The initial approach is to have healthy crop rotation,’ says Professor Noa Simon of BeeLife. ‘The problem is that crops are rotated too quickly: cereal year one, cereal year two, sugar beet year three. But you need to keep the same crop for five to seven years to help pollinators.’

Both Simon and Hans Dreyer at the FAO think IPM should be the cornerstone of crop protection and that farmers should ensure they are sowing the appropriate crop. ‘If you are sowing oil seed rape in Sweden it makes sense to sow the local variety rather than one from southern Spain,’ says Simon. ‘The local one has had generations to build up resistance to local pests and their phenotype will be more robust and less susceptible.’

Farmers can also employ a ‘push and pull’ system, in which crops are grown near plants that naturally push away pests and pull in their enemies. For example, a maize field vulnerable to stem borer moths could be surrounded by a border of napier grass, a plant that is more attractive to the moths than maize (the ‘pull’ part of the system). The forage legume silverleaf could then be planted within the maize. This plant releases semiochemicals that repel the moths (the ‘push’ element). If this doesn’t work, then you take advantage of natural predators, such as birds and hoverflies. Biotechnical options, such as caging the queen bee so that parasites cannot reproduce, can also be applied. 

‘Only then should you look at pesticides – first the “soft” ones, then the “hard” ones,’ says BeeLife’s Simon. ‘Options include garlic-based sprays, essential oils and organic acids. As a last resort, when nothing else works, you turn to synthetic pesticides. But we don’t often see this sequential approach followed.’


Concerns about neonicotinoids were first raised in 1996, a year after they were introduced, by French beekeepers who reported that their bees had begun to die. ‘We know even tiny amounts of neonicotinoids have a lethal effect – just one part per billion in nectar can impair bees’ ability to navigate and egg laying by queens,’ says Goulson. ‘It has also emerged that neonicotinoids are much more persistent and get deep into soils, contaminating streams and hedgerows.’

The impacts of neonicotinoids do not dissipate slowly. ‘They are persistent products so it will take perhaps 80 years for the environment to become cleaner,’ says Professor Simon. She points to the impact of the herbicide Atrozine, which was banned in the EU in 2003, but residue of which is still found in soils, water and foodstuffs. 

On a more positive note, Goulson reports that there is ‘clear evidence’ that the concentration of neonicotinoids in bee food is lower since the ban. Anecdotally, news from beekeepers is also encouraging: according to BeeLife, they are seeing fewer dead honey bees and more are surviving winter. ‘It is too early to say whether the ban has had an impact on invertebrate life,’ says Goulson. ‘It takes time for things to respond to change, even if it can. That’s the problem with damaging biodiversity – there’s no guarantee that when you finally take away the chemicals the bees will return. It may be several years or a decade before we know if the bees, the moths, the wasps or the beetles can recover.’

Given the concerns about the impact of pesticides, you might expect their use to be strictly governed, perhaps by a global convention. The reality, points out Buglife’s Shardlow, ‘is that 35 per cent of the world has no pesticide legislation. The manufacturers can continue to sell their wares around the world and make a lot of money and will continue to do so until the last drop of neonicotinoid has been sold. I think that is immoral.’

Geographical 2019 01 CroplandsPesticides

Pesticide use
This cartogram shows the average use of pesticides per area of cropland. The transformation is based on a gridded cartogram technique in which each grid square over land is proportional to the total area used for crops. The colour key shows the annual agricultural use of pesticides divided by the area of cropland in each country. Pesticides include fungicides and bactericides, herbicides, insecticides, plant growth regulators, seed treatment fungicides, seed treatment insecticides, mineral oils, rodenticides, and disinfectants. Data was compiled by the FAO.

The Rotterdam Convention governs certain hazardous chemicals and pesticides but mainly relates to international trade, is not legally binding and leaves it up to signatory nations to decide whether or not to use the chemicals. Elsewhere, pesticide use is overseen by regional jurisdictions – where they exist.

In 2013 the FAO produced an international code of conduct for pesticide management, from testing to use and monitoring, which was aimed at government authorities and the pesticide industry. The code places an emphasis on avoiding pesticide use if possible, arguing that ‘providing farmers with access to local supplies of well adapted and good quality seeds… helps to prevent the spread of pests and diseases… and reduce reliance on pesticides’.

However, as Hans Dreyer, a senior director in the FAO’s Plant Production and Protection Division (AGP), acknowledges: ‘Our code of conduct is well referenced but it is voluntary. We support countries in trying to refrain from using really hazardous pesticides and help them to impose proper regulations. But many countries do not have the elaborate risk procedures that are found in the EU, their institutions are not as strong.’

Professor Simon points out that seed treatments for some crops have been banned in countries such as France, Germany and Belgium but not elsewhere. She wonders whether this means pesticides are expected to recognise international boundaries. ‘The basic precautionary principles that should be in place with pesticides are not always applied,’ she says. ‘We know pesticides are always going to come onto the market. What is important is that we have a strong risk assessment regime that looks at risks in the short and long term. If we don’t put the systems in place we will never know if we are safe or not. At the moment, the issue is dealt with the wrong way around. We wait until a crisis is seen in bees and then the pesticides are reviewed. This should be established in advance.’

Goulson too is unhappy about how crop controls are regulated. ‘The regulatory authorities in North America are more gung-ho than Europe,’ he says. ‘They have looked at exactly the same evidence and drawn different conclusions. [Atrozine, banned in the EU, continues to be among the most widely used herbicides in the US.] There’s been a recurring pattern for 70 years. A pesticide is introduced, we’re told it’s benign to people and the environment. Eventually it transpires, usually after decades, that this is far from the truth. It gets banned, is replaced by something else and the process repeats itself. The regulatory process has let us down.’

‘Pesticides need to be tested regularly, which is easier said than done,’ acknowledges Dreyer. ‘Pesticides have developed significantly since the 1950s. While the volume of pesticide has reduced, their toxicity has increased – so you can get the same risks.’

The next generation of pesticides
As well as trying to overturn the neonicotinoid ban, some agrochemical companies are developing alternatives. The concern is that these pesticides are not only in development but are already being used or are moving through the regulatory processes. They include sulfoxaflor, cyantraniliprole and flupyradifurone.

Some of these pesticides are used as foliar sprays, others are coated onto seeds to protect them from soil pests – when the seed germinates, the pesticide is absorbed and spreads through the tissue. It eventually reaches pollen and nectar, which is how pollinators are exposed.

The companies producing sulfoxaflor (Dow Agrochemicals) and flupyradifurone (Bayer CropScience) have published scientific articles asserting that these substances are not neonicotinoids. However, a study published in the journal Nature in 2018 concluded that ‘chronic exposure to the sulfoximine-based insecticide sulfoxaflor, at dosages consistent with potential post-spray field exposure, has severe sub-lethal effects on bumblebee (Bombus terrestris) colonies.’
Sulfoxaflor is registered in 47 countries but its registration in France was overturned in 2017. Cyantraniliprole has been authorised for use in the US, Canada, China and India. Flupyradifurone is a systemic insecticide aimed, says its manufacturer Bayer, at the target markets of the US, Europe, India and China. Some of these pesticides are neurotoxins that target the same receptors in insect brains as the neonicotinoids. ‘Many of them sound and look like neonicotinoids,’ says Goulson.


Conservationists also feel the dice are loaded against them and that a deep-seated prejudice prevails in regulatory authorities. ‘For many years, bee keepers have been portrayed as the trouble makers,’ says Simon, ‘but they are just conveying the message. They are able to monitor what is happening. They are permanently in the field.’

‘There’s a bubble in which the industry can maintain their belief about certain chemicals and their effectiveness,’ adds Shardlow. ‘The saying goes that history is written by the victors but in this case the wealth and power of the losing side means they are writing their alternative history. It’s the same approach that was taken over DDT. When it was banned, they said Rachel Carson was personally responsible for thousands of malaria deaths. It was absolute nonsense.’ Shardlow is referring to the author of Silent Spring, the book that led to the ban of the insecticide DDT, one use of which was to kill malarial mosquitoes. As part of the chemical industry push back, claims were made that the ban led to a rise in malaria and the deaths of millions of people. Shardlow says that the industry is taking the same approach now: rather than acknowledging the problem caused by pesticides, they are arguing that there will be greater pest problems and lower crop yields if pesticides are banned.

shutterstock 1168167448A tractor equipped with a sprayer works its way through a field of crops

A source of frustration among conservationists is the way that the concept of integrated pest management (IPM), which asserts that pesticides be used as a last resort, appears to have slipped off the radar. ‘In the EU all farmers were supposed to implement the concept and use alternatives to pesticides but it just hasn’t happened,’ says Goulson.

On the other hand, Dr Chris Hartfield, senior regulatory affairs officer for the UK’s National Farmers’ Union (NFU), argues that this portrayal of farmers is unfair. ‘It’s disingenuous to say we are locked into a mentality of “pesticides first”,’ he responds. ‘Pesticides are a costly input and farmers ensure there is good justification to use them.’

Hartfield also maintains that criticism of farmers’ attitude towards IPM is unfounded. ‘We recognise this should be at the heart of what farmers do,’ he says. ‘We have more than 20,000 UK farmers with a collective four million hectares currently recording their approaches [using IPM]. The reality is they already rotate their crops and implement other measures that are part of integrated pest management without necessarily knowing that is what it is called.’

It hardly needs pointing out that the farming industry’s response to the ban on neonicotinoids has been broadly hostile. Sugar beet farmers have argued – with justification – that there is no alternative to neonicotinoids, while the sector more widely has said farmers will simply turn to more harmful pesticides that are not banned. Hartfield agrees that a precautionary approach should be applied but argues that ‘unintended consequences’ have occurred because the ban was disproportionate. ‘Farmers have simply turned to the next pesticide along the line, which can mean pyrethroids, older chemicals and sprays. If you ban something you need to have confidence that what replaces it is less damaging.’

Paradoxically, more pesticide-treated crops than ever may now be in circulation. ‘Yields of oil seed rape have gone down in the EU, but the demand for foods that contains it remains the same,’ says Hartfield. ‘To meet that demand, oil seed rape is being imported from outside the EU with a strong likelihood that it contains neonicotinoids.’

Neither are pesticide manufacturers taking the restrictions lying down. German pharmaceutical company, Bayer, is involved in a protracted dispute with the General Court of the European Union over its neonicotinoid, imidacloprid. In May last year, the court ruled that the precautionary principle employed by the EU meant that it did not have to wait until it was clear that harm had been caused before taking measures such as bans or restrictions.

Bayer has since appealed against this ruling, arguing that the interpretation of the principle and EU law are not legally founded and that the decision-making process was flawed and should be reconsidered. Bayer says its stands by the safety of its products.

Commuter bees
Across large parts of the United States, colonies of bees are transported long distances in purpose-built trailers to pollinate inter-state crops and fruit trees. Up to 30 billion bees are transported from other states to pollinate the almond crops in California. Many colonies are repeatedly moved over several months to a series of large monocultures. The phenomenon has been associated with poor bee health (including the spread of the varroa mite), weakened bee immune systems and colony collapse disorder, whereby the majority of worker bees in a colony disappear, leaving a queen bee behind.


Technological advances are likely to shift the parameters of the debate. Depending on your perspective, the potential opportunities offered by robotics and genetic engineering will either be reassuring or deeply disturbing.

At least five companies are working to develop robot bees that could be controlled in swarms to pollinate crops and be impervious to insecticides. Last year scientists at Delft University of Technology developed a prototype bee-like drone, whose wings beat 17 times per second to generate the lift needed to stay airborne. The robotic insect has a 33cm wingspan and weighs 29 grams, making it 55 times the size of a fruit fly. Harvard is also looking at such developments. ‘If we’re not careful we could end up with a situation where we have an environmental market for something we get for free,’ says Matt Shardlow of Buglife. ‘It could be in some companies’ financial interests to keep that going.’

Other researchers are studying whether it is possible to genetically engineer bees to be resistant to pesticides. By using CRISPR technology – a molecular tool that can amend an organism’s genetic code – it is possible to insert a desired trait into the specimen in question, such as a honey bee. Inevitably, bee keepers have labelled these ‘frankenbees’. The first genetically modified honey bee queens were born in a laboratory at Heinrich Heine University in Dusseldorf in 2014.

dsc 0483 2The DelFly Nimble, a robot designed at Delft University of Technology to mimic the flight of bees

‘Do we want to take honey bees into such a dark place?’ asks Shardlow. ‘It would mean that the countryside becomes a living hell for any pollinator that isn’t a honey bee. They will be sprayed to death. It just moves us closer to the collapse of the natural eco-system. Perhaps people forget that honey bees do not pollinate every flower. Our wild plants will disappear and we end up with a world where only the rich can afford pollinated food. A world where pollination is only available to those who can afford it, where many people have no access to fruit, is truly terrifying and will lead to massive societal pressures. It begins to look like something out of Blade Runner. We lose the beauty and wonder and we expose ourselves and other animals to risks needlessly.’

The prospect also horrifies Goulson, who forecasts that it would instantly remove the incentive for farmers to reduce pesticide use. ‘It would mean the end of the wild world and all the beauty that is inherent in it.’

Dreyer of the FAO is also cool on the concept of genetic engineering. ‘It depends how you modify the bee,’ he says. ‘What kind of pesticide-resistant trait would you modify and in what gene? And what happens when the bee detoxifies the chemical – what does that mean for the bee? And how could honey produced by that bee have no pesticide residue in it?’ Given honey is one of those elemental products that consumers broadly consider to be pure, Dreyer struggles to see the commercial viability of such processes. ‘We are not actively pushing this,’ he adds. ‘It’s up to individual countries to decide whether to pursue it. Rather than GM bees, we would prefer to see a sustainable landscape where bees can survive.’

Farming unions play down such spectres. ‘I don’t believe we are going to see robot bees any time soon,’ says the NFU’s Hartfield. ‘We are going to be reliant on real insects. That said, we need to encourage innovation to overcome the challenges we face. Unfortunately, the extremely precautionary and conservative pesticide regulations we face are stifling that.’

However, Dreyer and the FAO do see some potential good arising from advances in technology. ‘Pest control will become more knowledge intensive,’ says Dreyer. The FAO sees plenty of potential positive uses, some of which are already in operation. ‘Robots are at a very early stage,’ says Dreyer. ‘But if they are able to distinguish a weed from a crop, then they may be part of a future where herbicides are used less on crops such as cotton.’ The potential for biopesticides that deploy natural pheromones to deter pests may also have potential, he says, but ‘while a lot of research is being done, it is too risky at the moment to be used in large-scale trials’.

The potential benefits of so-called ‘precision agriculture’ are recognised across the spectrum. ‘This may mean you can apply pesticides exactly where they are needed and could be a step in the right direction,’ says Goulson. ‘But it is simplistic to think we can solve everything through technology.’

Vital statistics
The absence of bees and other pollinators would wipe out coffee, apples, almonds, tomatoes, strawberries, pepper, onions and cocoa, to name just a few of the crops that rely on pollination. In addition, almost 90 per cent of wild flowering plants depend to some extent on animal pollination. A single honey bee will typically visit around 7,000 flowers a day, and it takes four million flower visits to produce a kilogram of honey. Annual honey production from the western honey bee is 1.6 million tonnes.


The fear for conservationists is that many politicians and leaders will not listen to such warnings. Or, if they do, will simply say ‘so what? I don’t care’ and feel that their hardcore base of support will unquestioningly support them. Yet Shardlow is optimistic. ‘There are plenty of people out there who get the importance of this. The public understands it, their mood on pesticides has changed enormously. Politicians may not always be dynamic but we know that many understand the seriousness of this. We have perhaps 20 to 40 years to turn it around, so it’s not over yet.’

At least all sides of the debate agree that the public needs to think harder about the implications of their shopping habits. ‘This isn’t about what farmers do, it’s about where food production sits,’ says Hartfield. ‘Pesticides are a fundamental part of our current food production system. All of us, farmers, retailers and shoppers have bought into this system because it gives us safe, affordable and regular supplies of food.’ If we want our food to be produced in a different way, Hartfield argues, then we all need to buy into the fact that this could come at a greater cost of production.

Ultimately, dealing with the issues surrounding pesticides will involve taking on other pressing concerns. A warming climate, for example, means more pests. ‘We would prefer the problem to be simple,’ says Shardlow. ‘Unfortunately, pollinators aren’t going to conform to that. Insecticides make them vulnerable to disease. Landscape changes make them go locally extinct. Climate change adds more pressure. Car fumes make bees less able to detect honey. We have to bear down on all of these.’

This invites the question of whether a world without pesticides is even possible. ‘I feel sometimes as though I am a lone outrider but I firmly believe we can grow what we need without them,’ says Goulson. ‘Organic yields are 10 to 15 per cent lower than intensive farming yields but we waste more than a third of the food we produce and a high proportion of it is grown for animals. If we cut back on red meat and waste we have more than enough land to feed everyone with organic food.’

Such a rethink is not radical, says Professor Simon. ‘Agriculture has been around for thousands of years and people have still survived and eaten even though they didn’t have the technology we have today,’ she says. ‘Yet we have the attitude of “we have a problem, let’s take a pill to solve it”. There is enough proof and tools for farmers to choose the right way. The problem is they face a lot of pressure from industry not to change.’

The FAO agrees that a different mindset is essential. ‘We need to use technology to solve problems, not create more of them. We need to ask ourselves why we have pests in a particular place, not just say that “we have pests, so let’s use chemicals to solve the problem.” That’s asking the wrong question. The better we understand the systems at play the more options we haves to find alternatives to chemicals.’

Does a political consensus exist? Goulson doubts it. ‘Sadly, I don’t think all that many people care about insects. Some will get upset or notice if they don’t see a particularly colourful butterfly but most people won’t be bothered about moths.

‘The world is currently not sufficiently co-ordinated, nor altruistic,’ he continues. ‘National priorities and interests seem to trump everything. There is no question that we are facing an ecological armageddon, of climate change, pesticide use, massive loss of habitat, soil erosion and plastic pollution. Until we start paying attention to the wider picture, I’m not optimistic that we will help nature recover. But giving up is not an option.’

This was published in the January 2019 edition of Geographical magazine

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