The Buzz Around Bee Decline
Are Super Robotic Bees the Future of Farming?
Around 70% of crops need pollination; however the number of insect pollinators has fallen dramatically over the past 50 years, a problem that threatens the future of the food industry. Eloise McLennan explores what is causing the decline, and whether robotic bees could provide a solution
Where have all the bees gone? Those fuzzy little beasts of burden known for terrorising innocent picnic-goers with dive-bombing manoeuvres and threats of stinging stabs. With more than 20,000 species of bee currently in existence – 250 in the UK alone – it’s difficult to imagine what life would be like without these fuzzy flying insects. But over the past decade, beekeepers and conservationists have noted a steep decline in the bee population, a trend that threatens to devastate food security around the world.
Although they are most commonly associated with honey, around of a third of the food that we eat comes from crops that are pollinated by insects such as bees. In fact, many of the crops pollinated by creepy crawlies produce some of the tastiest produce. Tomatoes, courgettes, strawberries, even coffee and chocolate, need these insects to transfer pollen from flower to flower in order to produce yields. Fewer bees means reduced pollination, which may result in less honey and a limited range of plants for us to eat.
“We couldn't feed the seven billion people, or what will soon be reaching ten billion people, without having a good supply of bees,” says Dave Goulson, a leading bee expert and a biology professor at the University of Sussex.
In 2013, pesticide manufacturer Syngenta described bee health decline as among the biggest challenges facing agriculture. Given that in 2014, a review published by the Department of Food and Agriculture estimated that these insects added approximately £600m per year to the value of UK crops through increased yield in oilseed rape and the quality of various fruit and vegetables, it’s no wonder that the dramatic decline in bees has sparked frenzy in the food industry.
But what is behind the falling number of insect pollinators? And could technology hold the key to pollinating crops in the future?
Why are the bees declining?
Insect pollinators are under attack from multiple threats in the UK, but there is no single factor responsible for the falling number of bees. Instead, it is commonly understood that a combination of factors, including habitat loss, disease and the use of pesticides in industrial farming, have contributed to changes in pollinators and pollination in areas where declines in bee health and numbers have been observed.
While the extent to which each of these factors impacts the bee population is unclear, it is evident that changes in agricultural land use and rapid urbanisation have had a significant effect on the natural behaviour of bees.
We've been losing habitats, particularly flower-rich habitats like meadows, for at least a hundred years
Over the course of the 20th century, the UK lost just short of 98% of its grassland. The knock-on effects of intensified agricultural land management, largely fuelled by policies to enhance food security and increase production, meant that the flower-rich habitat in which bees thrived gave way to vast monocultures of crops with little to offer insect pollinators.
“We've been losing habitat, particularly flower rich kind of habitats like meadows, for at least a hundred years so there is less food for them and less places for them to nest,” explains Goulson. “We replaced a lot of that flowery habitat with big monocultures of crops; fields of wheat and barley, which have nothing really to offer a bee.”
New and foreign diseases have also been linked to the declining bee population in the UK. Honey bees in particular have been widely exported and shipped from country to country, exposing them to parasites and illnesses that they are ill equipped to handle. For western bee keepers, the varroa parasite has been a key cause of bee death.
Originating in Asia, the varroa mite was not seen in Europe until the 1970s. Unlike their Asian counterparts, western bees had no defence against the parasite. The result was a disaster for beekeepers. Varroa mites transmit pathogens like viruses and bacteria, which are damaging to bee health, wiping out entire populations of western honey bees over recent years.
Poisoning pollinators: the threat of insecticides
Insecticides have been around for decades, roughly since the 1940s, and over the years they have been no stranger to controversy. Given that a broad range of commercially available pesticides belong to the same family of chemicals as nerve gases developed during the Second World War, it’s hardly a surprise that the industrial use of similar chemical compounds in agriculture has come under heavy fire from critics.
Currently at the centre of the pesticide debate is a highly controversial group of insecticides known as neonicotinoids (or neonics). Introduced in the 1990s, neonics are now the most widely used insecticides in the world. They are primarily used as a seed treatment, which is applied before the seed is sold on to farmers. Unlike contact pesticides, which remain on the leaves of a plant and have no residual activity, neonics are systemic.
As a treated seed germinates, the chemical coating is absorbed into the seedling’s tissue, moving through the xylem into the leaves, fruit, flowers, pollen, nectar and guttation fluid as the plant grows. If a crop pest tries to take a bite out of a treated plant, the insecticide will attack the insect’s central nervous system and bind to the receptors of the enzyme nicotinic acetylcholine, resulting in convulsions, paralysis and death.
Currently at the centre of the pesticide debate is a highly controversial group of insecticides known as neonicotinoids
While small doses aren’t usually enough to be fatal for bees, they are sufficient to impair pollinator health, including disruption to foraging behaviour, homing ability, communication and larval deve lopment.
“The problems have started to become apparent,” says Goulson. “Because they are systemic and they go throughout the plant, they go into the nectar and the pollen, which means that if you've got a field of flowering oil seed rape, which attracts tens of thousands of bees, they are all being dosed with insecticides.”
Neonicotinoids are supposed to be more targeted than non-systemic pesticides. But there is mounting evidence to suggest that their effects extend beyond the boundaries of crop fields.
“It turns out that most of the chemical isn't sucked up by the roots of the plant at all,” says Goulson. “It's going into the soil and leaching into streams and being taken up by wildflowers with their roots in the edge of the field. So, hedgerow, shrubs, trees, wildflowers.”
The RoboBee. Image courtesy of Wyss Institute at Harvard University
Autonomous flying robots: using technology to pollinate the food of the future
Tackling such a controversial and potentially devastating issue is a complicated task for the global food industry. But while researchers and environmental activists search for a way to reverse the damage already done to the bee population, tech-minded scientists and engineers have been exploring an alternative approach to the problem of pollination – using specially modified drones to create a fleet of tiny robot bees.
Now, for anyone who has seen Black Mirror, the idea of creating a robotic bee arsenal may be less than appealing, but the reality of these artificial pollinators is a far cry from their on-screen depiction. Robot bees don’t look like traditional black and yellow-striped bees that populate the British countryside; rather, they are modified versions of the robot quadcopters already on the market – albeit much, much smaller.
One such drone is the brainchild of Eijiro Miyako, of the National Institute of Advanced Industrial Science and Technology in Tsukuba, Japan. The manually controlled quadcopter is coated with animal hair bristles to mimic the fuzzy body of a real bee, as well as a special sticky gel, developed by Miyako in 2007. Unlike conventional gels, which can lose their adhesive properties over time, Miyako’s ionic liquid gel stays sticky after multiple uses, making it ideal for transferring pollen from one plant to another. In experiments, the prototype was able to collect pollen from the pollen-bearing antlers of an open bamboo lily (Lilium japonicum) and transfer it to the pollen-receiving stigmata of a different flower, much in the same way an insect would.
Trying to manufacture a viable alternative just seems like a really clumsy and expensive alternative to something that we already have
This isn’t the first time scientists have experimented with robotic pollinators bees. In 2013, a team of researchers from the Wyss Institute for Biologically Inspired Engineering at Harvard University and the Harvard John A Paulson School of Engineering and Applied Sciences revealed a similar concept – the RoboBee.
Roughly half the size of a paperclip and weighing less than a gram, the man-made design used two wafer-thin wings to achieve vertical take-off, hovering and steering. But, while this was a big achievement for the team, the design was a long way off competing with the naturally occurring efficiency and capability of real bees. That said, the project has made significant progression since 2013. Last year, the team unveiled the latest-generation RoboBee, a hybrid system described in Science Robotics as being able to fly, dive into water, swim, propel itself back out of the water and land safely.
Artificial pollination isn’t anything new. Farmers in China's Sichuan province have been using pots of pollen and paintbrushes to hand pollinate fruit trees for ye ars, after excessive pesticide use and loss of natural habitat eradicated the wild bee population. But compared to bees, this is a clumsy and arduous process. While the prototypes developed by both the Japanese and American teams are merely that – prototypes – which are nowhere close to mass market, they demonstrate a potential, if imperfect way to pollinate plants without insects. But not everyone is sold on the prospect of these artificial pollinators.
“It would be extremely expensive and costly for the environment to go down that route when we already have bees that are free, that are self-replicating, are carbon neutral and have been pollinating for 120 million years,” argues Goulson. “Trying to manufacture a viable alternative just seems like a really clumsy and expensive alternative to something that we already have. That money could be so much better spent looking after the bees that we've already got.”
Genetic modification and the rise of the superbee
Robotics is not the only avenue being explored by scientists. While the role of neonics is debated by politicians, lobbyists and activists, an unusual source has been working on a way to combat the threat of varroa mites, using yet another controversial technique – genetic modification (GM).
Over the past decade, agricultural behemoth Monsanto has become something of a villain in popular culture, largely due to the company’s GM organism seeds. But, while opponents object to the company’s so-called ‘frankenfood’ approach to agriculture, Monsanto has used its extensive resources to target one of the key identified causes of bee decline.
In 2012, the company acquired Beeologics, a small company based in Israel which gained international attention for developing Remebee, an anti-viral treatment designed for use in honeybees affected with Israeli Acute Paralysis Virus. The vaccine-like medicine is based on a Nobel Prize-winning technology, called ribonucleic acid (RNA) interference, which is a process that cells use to turn down or suppress the activity of specific genes.
RNA interference occurs naturally in cells. Strands of messenger RNA (mRNA) carry the code needed to build specific proteins, but if a strand of RNA attaches itself to the mRNA, then the protein-making process is interrupted. This interference can be induced by feeding bees a sugar syrup concoction that has been laced with RNA that has been specifically coded to attack the mRNA that varroa mites use to produce the proteins that enable it to eat, breathe and reproduce.
The other 19,999 species of bee that we hadn't protected would be wiped out
Since acquiring Beeologics, Monsanto has been developing a product to do just that. Currently in the phase three stage of the company’s research and development pipeline, the sugary syrup is expected to appear as an addition to larval food, where it will metabolise and enter the bloodstream of bees.
“The appeal of this approach is the ability to target just the varroa mite, while reducing or eliminating the use of chemical pesticides in honey bee colonies,” says Dr Jerry Hayes, Monsanto honey bee health lead.
But as with the rise of robotic pollinators, activists and bee researchers are sceptical about GM pollinators. Setting aside the standard debate as to whether GM is good or bad, as well as Monsanto’s less than spotless environmental reputation, the fact remains that research into RNA interference in bees is still very limited.
“In theory we could genetically engineer pesticide resistant honey bees,” says Goulson. “But, that would then mean that there would be less pressure on farmers to not use pesticides and essentially would mean that the other 19,999 species of bee that we hadn't protected would be wiped out.”
Preventing the beepocalypse: how to save the bees we have left
They may be intriguing ideas, but, as it stands, both the robotic and GM concepts are imperfect solutions to a rapidly developing problem. Neither option addresses all three core reasons thought to be behind the decline of pollinators, so while they may alleviate some of the strain put on real bees, it is unlikely that they will have great impact on the overall population.
Besides, as Goulson states, there are thousands of different species of bee. While we may be able to replicate one or two types using robotics or genetic modification, it will be a slow and costly process. And not all bees can pollinate all crop types.
Honeybees, which have been the key focus of research groups, don’t fit the flowers of tomato plants so protecting just this one species could have a direct impact on tomato yields.
So what can be done to ensure a thriving population of bees in the future?
In the UK, environmental secretary Michael Gove has already announced plans to back a total ban on insect-harming pesticides in fields across Europe, plus the Centre for Ecology and Hydrology has begun a trial on 15 large arable farms in central and east England to see if planting long strips of bright wildflowers through crop fields can boost the natural predators of pests and reduce pesticide spraying.
Whether these small efforts will have the desired effect is unclear. But, without serious commitment from agricultural powerhouses, you may have to kiss one third of our delicious food goodbye.