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Thousands of football-shaped hornet nests are now dotted all over the forests of Aquitaine, the south-western region of France hugely popular with British tourists.The article says just a few of the hornets can "can destroy a nest of 30,000 bees in just a couple of hours." It also says that France now has to import honey. 25,000 tons of honey are now imported into France each year. Global warming is already making many changes to ecosystems and the economy in Europe. The hornets are expected to eventually make it to Britain.
"Their spread across French territory has been like lightning," said Jean Haxaire, the entomologist who originally identified the new arrival.
He said he had recently seen 85 nests in the 40-odd miles which separate the towns of Marmande and Podensac, in the Lot et Garonne department where the hornets were first spotted.
The hornets can grow to up to 1.8in and, with a wingspan of 3in, are renowned for inflicting a bite which has been compared to a hot nail entering the body.
As he inspected the yard, he found that the missing bees, foragers who roam for pollen, had left their queen and brood. Just as mysteriously, the dead colonies contained honey, usually plundered quickly from abandoned hives by other bees, wax moths or hive beetles.
Out of 400 hives in the Florida yard, only about 40 housed live bees. Most were empty of adults. Hackenberg, who has spent 45 of his 58 years as a beekeeper, hauling insects from state to state to pollinate crops, had never seen the like. Gathering dead bees, he ferried the samples to researchers in Pennsylvania.
In the past, hives succumbed to varroa or tracheal mites and amoebic infection. But when researchers examined Hackenberg's bees they found blackened and swollen organs. "We found many abnormalities," says Dennis van Engelsdorp, Pennsylvania's state apiarist. "Scarring on the digestive tract, kidneys swollen and scarred. Even the sting gland had evidence of a fungal or yeast infection."
The dramatic scene in Florida was the first reported instance of an alarming phenomenon called Colony Collapse Disorder. According to Montana's Bee Alert Technologies, CCD has hit 35 states, and Van Engelsdorp estimates that 25% of apiarists suffered losses, with up to 875,000 out of 2.4m hives infected. Collapse within each hive ranges from 35% to 90% of the bee population.
Bees have vanished in Canada, Brazil, India and Europe, although CCD remains unconfirmed. Barry Gardiner, parliamentary under-secretary at the Department for Environment, Food and Rural Affairs, told the House of Commons this month that the National Bee Unit had received reports of isolated UK cases. "However, overall percentage losses are similar to previous years, albeit reflecting the gradual increase seen in the last five years," he said.
Reduced pollination
Faced with a dramatic die-off among Apis mellifera, the non-native honeybees that pollinate a third of US crops, scientists are working flat out to isolate the cause and find a remedy. Without bees, pollination is dramatically reduced and crops are put at risk. Fewer bees have already triggered higher US pollination fees. As bees pollinate 90 crops worldwide, the threat to food supplies is grave. Next week, two new bills will be tabled in the US Congress, to raise the alert about the threat and to appropriate desperately needed research funds.
Vanishing bees are not entirely new. The earliest known instance dates from the 18th century. Disappearances in the US were noted in 1869, 1923, 1965 and the 1970s. Since then, Pennsylvania's bee colonies have dwindled from 80,000 to 38,500. Unusual deaths surfaced in some eastern states in 2004, but last winter's hive collapses eclipsed any mite infestations.
So why would socially sophisticated insects abandon their young and their queen? Theories abound, ranging from an al-Qaida plot to wreck US agriculture to wireless waves from cell phones.
Bees found in hives with CCD were "infected with an extremely high number of different disease organisms", Penn state entomologist Diana Cox-Foster told Congress in March. Did this indicate catastrophic immune collapse, perhaps destroying foragers' navigational systems? The same Congress also heard that the economic worth of the honeybee in the US is valued at more than $14.6bn a year.
The absence of pests such as varroa suggested the presence of some toxin, perhaps from fungi known to be pathogenic since the 1930s.
In April, Californian investigators said a single-celled parasite, Nosema ceranae, might be to blame, but cautioned that their findings were "preliminary." Other researchers say the fungus indicated a suppressed immune system.
"Nosema may be a player," says Van Engelsdorp, "but not the smoking gun." American researchers, he says, are focusing on three broad possibilities: a viral disease caused by a new or mutated pathogen; environmental contaminants, such as pesticides applied in the field, or used to control mites in hives; and nutritional stress, perhaps linked to drought conditions last summer. Or the disappearances might be caused by a combination of some or all these factors in a "perfect storm," with fungi executing the coup de grâce.
The pathogen angle is being pursued by Cox-Foster. "We have found some new organisms that appear to be correlated with CCD," she explains. "They may potentially be a cause." Her research, shared with Columbia University's Ian Lipkin, is due to be published shortly in the journal Science. Still, this remains a grey area. "There are places this pathogen is found that have not reported CCD, so we do expect to find additional triggers," says Cox-Foster.
When I spoke with Hackenberg, he was in Maine getting ready to load hives used to pollinate the blueberry crop and then truck them south to New York for the cranberry crop. To date, CCD has cost him $460,000 - "We went from 2,950 to less than 800 hives," he says - and he has restocked with Australian bees. He is leaning towards an environmental culprit. "I think something causes memory loss in bees," he says, a possible explanation for navigational failure. He lays the blame on nicotine-based pesticides called neonicotinoids, which, Cox-Foster told Congress, are "known to be highly toxic to honeybee and other pollinators". Have neonicotinoid concentrations accumulated in plants, with fatal consequences for bees? Hackenberg cites anecdotal evidence of bees that vanished after foraging in corn, sunflowers, lawns or golf courses sprayed with neonicotinoids. Yet how do scientists explain the CCD outbreak in France, which banned the pesticide in 1999?
Others have blamed genetically modified crops, although entomologist May Berenbaum, who will address a congressional committee next week, notes that CCD is officially absent in Illinois, which grows GM corn. Intriguingly, she says the honeybee genome, published last October, shows the species has half the enzymes other insects use to fight poison.
The nutritional theory, perhaps precipitated by severe drought, evokes climate change - as does the possibility that global warming opened a window for a new pathogen, although this, too, remains little more than theory.
And while climate change is linked to die-offs in species unable to adapt fast enough to changing conditions, Van Engelsdorp suggests bees are unlikely candidates because they can survive in a whole range of temperatures. At the same time, he says much remains unknown about bee pathology. There is even debate about whether we can regard a single bee as a living organism, or as part of a super organism in which individuals survive as members of a collective.
Trucking hives
Then there are management issues with commercial bee operations, notably trucking hives thousands of miles to pollinate commercial crops. California's almond crop was serviced this year by more bees than exist in Pennsylvania, a perfect contagion scenario. As apiarists such as Hackenberg haul hives around the US, maybe bees are declining due to the stress induced by having to pollinate ever more crops, even as natural ecosystems are wiped out by urban growth.
Last September, the US National Academy of Scientists reported that honeybees, solitary bees and bumblebees are in steep decline. "There is real concern that CCD is an indicator of problems in the wider environment and with pollinators in general," says Van Engelsdorp.
Researchers talk about breeding new bees. But as bees disappear around the globe, there are fears that CCD is evidence of the deadly fallout visited on societies out of kilter with nature.
Defra urged to take threat seriously
Colony collapse disorder (CCD) has not yet arrived in the UK - officially at least. Despite some beekeepers reporting the disappearance of most of their bees when they opened their hives this spring, the government's National Bee Unit (NBU), based in York, says there is no evidence that the losses are caused by the mystery CCD plague sweeping the US.
Of the 6,500 colonies examined by government bee inspectors so far this year, 16.8% were found to be dead - slightly higher than at the same time last year. But by the end of the summer, when some 20,000 colonies will have been inspected, the government predicts that the mortality rate will be nearer 11% - the same as in the last few years.
According to a spokeswoman for the Department for Environment, Food and Rural Affairs (Defra), which oversees the work of the NBU, bee inspectors are attributing current mortalities in honeybee populations in the UK to the varroa mite.
The parasite, which feeds off the bees and their larvae, significantly weakening the colony's immune system, wiped out millions of western honeybees from the 1970s until the late 1990s. Its increasing resistance to chemical controls explains its alarming re-emergence.
Yet John Chapple, head of the London Beekeepers Association, who lost two-thirds of his 40 hives this year, says he does not know the cause of his bees' disappearance and the many deaths. "In my 20 years of beekeeping, there was no logic to it," he says. And he accuses Defra of not taking the problem seriously enough. "The bee losses are very patchy. They think it is varroa-related, but they haven't got the knowledge."
Tim Lovett, chairman of the British Beekeepers Association (BBKA), which has 11,000 members, warns that it would be "foolhardy in the extreme" for government to deny the possible emergence of CCD in the UK. To do so, he says, would put at risk the economic contribution bees make to agriculture and horticulture - an estimated £1bn per year. He criticises Defra for slashing bee research budgets, which has led to world experts on bee viruses being laid off from UK research institutes.
Next week, beekeepers will confront Defra officials, at an emergency meeting convened by the BBKA, over the "paltry" £180,000 being allocated to research.
John Howat,
secretary of the Bee Farmers' Association, will raise the concerns of
its 300 members, who own around 13% of the 240,000 hives across the UK.
"Less than 1% of the hives' value to the economy is being spent on
research and development," he says. "What kind of company would do
that? The government seems totally oblivious to the consequences of
honeybees being wiped out."
Alison Benjamin
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The
plight of the honeybee is the focus of The Food Programme. A commercial
beekeeper in Pennsylvania, USA - was the first to discover what's being
called 'colony collapse disorder.' He describes the effect on his
business. Scientists in the USA and in the UK discuss the possible
causes of CCD and the wider implications of their research findings.
Reporter, Jean Snedegar visits Pennsylvania to meet commercial beekeeper Dave Hackenberg and speaks to scientists at Penn State University about their latest research. Sheila Dillon is joined in the studio by Dr Richard Jones, director of The International Bee Research Association and by Dr Norman Carreck, bee scientist and keeper. |
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In Aesop's fable, the country mouse scurried home from the city with his tail between his legs. But in Paris, French bee-keepers are finding their charges have better luck in the buzz of the big smoke than they do in rural climes - living longer and producing more honey.
While bee colonies across rural France are dying in swarms, two beehives that have been on the roof of a giant exhibition hall beside the Champs-Elysées since last spring are thriving.
The experiment in urban living for bees is intended as a warning signal to the French government, which has been accused of ignoring the plight of rural bees and bee-keepers.
In May, the Grand Palais exhibition hall decided to place two beehives on the edge of its huge glass and steel dome. Each beehive contains over 80,000 "buckfast bees", a British species described by experts as "gentle, prolific and resistant". Four months later, more than 100lb of honey has been gathered from the two hives.
It is not the prestigious address or magnificent views which make the bees so productive. What they adore is the urban environment, even though it is heavily polluted by car exhaust.
"We notice that apiaries located in the heart of Paris get better results than those in the countryside," explained Nicolas Géant, the French bee-keeper who initiated the project at the Grand Palais in order to draw attention to the predicament of rural bees.
"Towns offer myriad small flowers in parks and on balconies, as well as a wide variety of trees along streets and in public gardens. By contrast, there is no longer enough food for bees in rural and cultivated areas. The mortality there is 30 to 50 per cent but very small in Paris."
Henri Clement, president of France's main apiarist union, Unaf, says changes in French agriculture have damaged the bees' habitat. "Both monoculture and the intensive use of pesticides, fungicides and fertilisers kill massive numbers of bees," he explained.
For the moment the new tenants of the Grand Palais seem to be enjoying their life in the busy capital. "We have not received complaints from them yet," jokes Majorie Lecointre, one of the managers of the exhibition hall. Three additional beehives will be placed on the Grand Palais roof early next year.
But the city slickers will not be enough on their own to save beekeeping - and the crucial role it plays in agriculture, severely under threat because of a dramatic decline in bee populations.
"People have to keep in mind that the future of beekeeping is not in cities," said Mr Clement. "Bringing bees into cities is just a way to ring the alarm bell for the French government. We need to have bees back everywhere in France because 35 per cent of global food resources depend on insects and 80 per cent of that is from pollination by bees."