Imagine a future where the only thing you could buy in McDonald’s was a piece of bread.

If it sounds too ridiculous to be true, then you don’t know much about the plight of the honeybee. If they keep dying at their current rate, Britain will lose a third of all the food we normally see on our dinner plate.

And that includes junk food.

Onions, cucumbers, pears, raspberries, leeks, avocados and macadamia nuts all depend on the honeybee for pollination, as do mustard, tea, fennel, kale and gooseberries.

Even the typical Big Mac is reliant on the humble bee, as it pollinates the alfalfa which feeds the cow whose meat would comprise the burger patty.

The honeybee is slight in size but massive in economic and nutritional power.

In the UK alone, bees contribute £200million a year to the economy through pollination, according to the British Beekeepers’ Association (BBKA). Worldwide, they pollinate some 90 commercial crops, including soya, corn, cotton and wheat.

But in just the past winter, 20% of all the honeybee hives in Britain have simply disappeared. In the United States, there’s already a name for it – Colony Collapse Disorder – as 2million hives (or one-third of the total) have been lost in just the past two years.

It’s a problem that one beekeeper termed “the bee Holocaust”. At these current rates, America is expected to be honeybee-free by 2035.

This trend has been noted from all over the world, from America to Australia, Italy, Greece and Brazil. And no one knows why it’s happening.

VANISHING INTO THIN AIR

So where are all the bees going? It’s a question that has puzzled scientists for the past few years, and it’s one that filmmakers George Langworthy and Maryam Henein set out to answer in a new documentary on the subject.

The film, The Vanishing of The Bees, opened in cinemas yesterday and investigates the origins and future of Colony Collapse Disorder (CCD) through captivating interviews with researchers, beekeepers, farmers and academics.

Characterised by large-scale disappearance of bees from a hive, CCD was first noted in the autumn of 2004, when Florida beekeeper David Hackenberg took a look inside one of his hives and realised that his bees had simply vanished.

All the worker bees were gone. And not in just one, but in 75% of all of 3,000 of Mr Hackenberg’s hives.

Oddly, the queen bee and baby bees were still present, a practice common to CCD but completely “unheard of” in nature, says Ms Henein.

“You never see mothers abandoning their young in nature. This, to me, represents humans abandoning Mother Earth and showed me that we needed to do something to stop it.”

Ms Henein and Mr Langworthy were immediately drawn to the mystery of the abandoned hives. No one single cause has yet been attributed to CCD, but scientists believe that pests (such as mites, viruses and bacteria), bad weather, pesticides, the importation of non-native bees to fill gaps in pollination, poor beekeeping (whereby bees are transported thousands of miles to pollinate crops from California to Maine and back again) and loss of natural habitat all play a part.

It’s often said that whatever begins in America soon crosses the pond.

But CCD is a phenomenon that hasn’t yet hit the UK, says Defra, the Department for Environment, Farming and Rural Affairs.

Yet just why Britain is seeing such a large loss of its honeybees, compared to typical yearly losses of around 5-10%, is unknown.

As for the beekeepers themselves, some think that it’s the pesticides that are posing the problem.

THE BEE KILLER

“If a pesticide is supposed to target the immune system of an insect in order to kill it, then what do we think is going to happen to a bee?” asks Mr Hackenberg, one of the unwitting stars of the documentary.

Mr Hackenberg was CCD’s whistleblower. The first beekeeper to present the disorder to researchers at Penn State University, he is convinced that a particular strain of pesticides – called neonicotinoids – are to blame.

“The scientists believe that something is breaking down the immune system of the bees, which is causing them to get sick, lose their memory, lose their way back home, and die off in their millions,” he says.

“Now, do I think it’s because of the pesticides? Well, I’ve been beekeeping for 40-something years and I never saw this problem before the neonicotinoids.”

Neonicotinoids are recently introduced systemic pesticides that tend to be sprayed over huge monocultures and, for that reason, are “toxic in their parts per billion”, says Mr Langworthy.

“You put one drop in a swimming pool and the whole pool becomes lethal.”

As honeybees fly from plant to plant collecting nectar, they ingest small amounts of the pesticide that become concentrated over time and slowly kill them, says Mr Hackenberg.

“You never know where a bee is going to fly to collect food, because they can fly off for miles in every direction. So if there’s bad food out there, they’ll bring it back into the hive.

“They’ll protect the hive from contamination by leaving home to die. But the thing is, the hive is already full of the infected nectar.”

These toxic pesticides aren’t just a problem for the bees. If that toxic nectar is turned into toxic honey, then what kind of effect is that having on human populations all across the world?

“Some scientists think these pesticides might be related to the increases in learning difficulties, autism and asthma we’re seeing,” says Ms Henein.

“People really need to start thinking about where their food is coming from and how it’s grown.”

Certain countries, like France and Italy, have outlawed these pesticides because of the effect on the honeybee. But red tape and big business are holding the US back from doing the same, Mr Hackenberg thinks, as “big monocultures like corn and wheat are much bigger industries than beekeeping by a long shot”.

Bees work together as one giant animal. And the work they do is tremendous. The BBKA estimates that if people were forced to take over the bees’ job of pollination in the UK alone, a workforce of 30 million would be required.

It sounds unimaginable, but it’s already happened in southern Sichuan, China, where pear trees are now pollinated by hand after the uncontrolled use of pesticides in the 1980s killed off the honeybee population.

WHAT YOU CAN DO

You can encourage bees into your garden or allotment, or even just on to your windowsill, by planting wildflowers, which bees can feed on for nectar, and by planting grass, which they can use to shelter from the rain.

You could also become a beekeeper. There are already 40,000 registered in the UK, most of whom treat it as a hobby rather than a profession. You can find out more at http://www.britishbee.org.uk.

The co-operative, which is supporting the Vanishing Of The Bees, also has lots of tips on how you can help the honeybee. Visit http://www.vanishingbees.co.uk /planbee to learn how.