Across America, millions of honey bees are abandoning their hives and flying off to die, leaving beekeepers facing ruin and US agriculture under threat. And to date, no one knows why. Michael McCarthy reports
Published: 01 March 2007
It has echoes of a murder mystery in polite society. There could hardly be a more sedate and unruffled world than beekeeping, but the beekeepers of the United States have suddenly encountered affliction, calamity and death on a massive scale. And they have not got a clue why it is happening.
Across the country, from the Atlantic coast to the Pacific, honey bee colonies have started to die off, abruptly and decisively. Millions of bees are abandoning their hives and flying off to die (they cannot survive as a colony without the queen, who is always left behind).
Some beekeepers, especially those with big portable apiaries, or bee farms, which are used for large-scale pollination of fruit and vegetable crops, are facing commercial ruin - and there is a growing threat that America's agriculture may be struck a mortal blow by the loss of the pollinators. Yet scientists investigating the problem have no idea what is causing it.
The phenomenon is recent, dating back to autumn, when beekeepers along the east coast of the US started to notice the die-offs. It was given the name of fall dwindle disease, but now it has been renamed to reflect better its dramatic nature, and is known as colony collapse disorder.
It is swift in its effect. Over the course of a week the majority of the bees in an affected colony will flee the hive and disappear, going off to die elsewhere. The few remaining insects are then found to be enormously diseased - they have a "tremendous pathogen load", the scientists say. But why? No one yet knows.
The condition has been recorded in at least 24 states. It is having a major effect on the mobile apiaries which are transported across the US to pollinate large-scale crops, such as oranges in Florida or almonds in California. Some have lost up to 90 per cent of their bees.
A reliable estimate of the true extent of the problem will not be possible for another month or so, until winter comes to an end and the hibernating bee colonies in the northern American states wake up. But scientists are very worried, not least because, as there is no obvious cause for the disease as yet, there is no way of tackling it.
"We are extremely alarmed," said Diana Cox-Foster, the professor of Entomology at Penn States University and one of the leading members of a specially convened colony-collapse disorder working group.
"It is one of the most alarming insect diseases ever to hit the US and it has the potential to devastate the US beekeeping industry. In some ways it may be to the insect world what foot-and-mouth disease was to livestock in England."
Most of the pollination for more than 90 commercial crops grown throughout the United States is provided byApis mellifera, the honey bee, and the value from the pollination to agricultural output in the country is estimated at $14.6bn (£8bn) annually. Growers rent about 1.5 million colonies each year to pollinate crops - a colony usually being the group of bees in a hive.
California's almond crop, which is the biggest in the world, stretching over more than half a million acres over the state's central valley, now draws more than half of the mobile bee colonies in America at pollinating time - which is now. Some big commercial beekeeping operations which have been hit hard by the current disease have had to import millions of bees from Australia to enable the almond trees to be pollinated.
Some of these mobile apiaries have been losing 60 or 70 per cent of their insects, or even more. "A honey producer in Pennsylvania doing local pollination, Larry Curtis, has gone from 1,000 bee colonies to fewer than eight," said Professor Cox-Foster. The disease showed a completely new set of symptoms, "which does not seem to match anything in the literature", said the entomologist.
One was that the bees left the hive and flew away to die elsewhere, over about a week. Another was that the few bees left inside the hive were carrying "a tremendous number of pathogens" - virtually every known bee virus could be detected in the insects, she said, and some bees were carrying five or six viruses at a time, as well as fungal infections. Because of this it was assumed that the bees' immune systems were being suppressed in some way.
Professor Cox-Foster went on: "And another unusual symptom that we're are seeing, which makes this very different, is that normally when a bee colony gets weak and its numbers are decreasing, other neighbouring bees will come and steal the resources - they will take away the honey and the pollen.
"Other insects like to take advantage too, such as the wax moth or the hive beetle. But none of this is happening. These insects are not coming in.
"This suggests that there is something toxic in the colony itself which is repelling them."
The scientists involved in the working group were surveying the dead colonies but did not think the cause of the deaths was anything brought in by beekeepers, such as pesticides, she said.
Another of the researchers studying the collapses, Dennis van Engelsdorp, a bee specialist with the State of Pennsylvania, said it was still difficult to gauge their full extent. It was possible that the bees were fleeing the colonies because they sensed they themselves were diseased or affected in some way, he said. This behaviour has been recorded in other social insects, such as ants.
The introduction of the parasitic bee mite Varroa in 1987 and the invasion of the Africanised honey bee in 1990 have threatened honey bee colonies in the US and in other parts of the world, but although serious, they were easily comprehensible; colony collapse disorder is a deep mystery.
One theory is that the bees may be suffering from stress as beekeepers increasingly transport them around the country, the hives stacked on top of each other on the backs of trucks, to carry out pollination contracts in orchard after orchard, in different states.
Tens of billions of bees are now involved in this "migratory" pollination. An operator might go from pollinating oranges in Florida, to apples in Pennsylvania, to blueberries in Maine, then back to Massachusetts to pollinate cranberries.
The business is so big that pollination is replacing honey-making as the main money earner at the top end of the beekeeping market, not least because in recent years the US has been flooded with cheap honey imports, mainly from Argentina and China.
A typical bee colony, which might be anything from 15,000 to 30,000 bees, would be rented out to a fruit grower for about $135 - a price that is up from $55 only three years ago. To keep the bees' energy up while they are pollinating, beekeepers feed them protein supplements and syrup carried around in large tanks.
It is in these migratory colonies where the biggest losses have been seen. But the stress theory is as much speculation as anything else. At the moment, the disappearance of America's bees is as big a mystery as the disappearance of London's sparrows.
Thursday, March 08, 2007
Fish contaminated with mercury 'pose worldwide threat to health'
By Jeremy Laurance, Health Editor
Published: 08 March 2007
A worldwide warning about the risks of eating mercury-contaminated fish is to be issued by an international group of scientists today.
Three times more mercury is falling from the sky than before the Industrial Revolution 200 years ago, the scientists say.
Fish absorb the toxic chemical, which pollutes the seas, posing a risk especially to children and women of childbearing age. The role of low-level pollutants such as lead and mercury on the growing brain has been known for decades and measures have been taken to reduce exposure to a minimum. But the scientists say more must be done.
The warning is based on five papers by mercury specialists summarising the current state of knowledge on the chemical published in the international science journal Ambio. Called the Madison Declaration on Mercury Pollution, it presents 33 key findings from four expert panels over the past year. Every member of the four panels backed the declaration which was endorsed by more than 1,000 scientists at an international conference on mercury pollution in Madison, Wisconsin, in the US last August.
However, it runs counter to research by British scientists last month which found pregnant women who ate the most fish had children who were more advanced, with higher IQs and better physical abilities.
The British researchers said that while mercury is known to harm brain development, fish also contain omega-3 fatty acids and other nutrients which are essential to brain development. They studied 9,000 families taking part in the Children of the 90s project at the University of Bristol and concluded, in The Lancet, that the risks of eating fish were outweighed by the benefits.
The US scientists focused on the risks of mercury which they say now constitute a "public health problem in most regions of the world". In addition to its toxic effects on the human foetus, new evidence indicates it may increase the risk of heart disease, particularly in adult men.
While developed countries have reduced mercury emissions over the past 30 years, these have been offset by increased emissions from developing nations.
The uncontrolled use of the metal in small-scale gold mining is contaminating thousands of sites around the world, putting 50 million inhabitants of mining regions at risk and contributing 10 per cent of the global burden of the pollutant attributable to human activities in the atmosphere.
The global spread of the threat is revealed in increased mercury concentrations now being detected in fish-eating species in remote areas of the planet. The impact on marine eco-systems may lead to population declines in these species and in fish stocks.
Professor James Wiener, of the University of Wisconsin, said: "The policy implications of these findings are clear. Effective national and international policies are needed to combat this global problem."
In the US, official government advice is for pregnant women to limit their consumption of all seafood, including white fish, oily fish and shellfish, to no more than 12oz (340g) a week in order to limit their exposure to mercury.
In the UK, the Food Standards Agency advises expectant mothers to avoid shark, swordfish and marlin and to limit their consumption of tuna, because these are the fish with the highest levels of mercury.
The key findings
* Three times more mercury is falling from the sky today than before the Industrial Revolution
* Eating fish is the primary way most people are exposed to the toxic metal
* There is solid scientific evidence of the toxic effects of mercury on the developing foetus
* Mercury exposure now constitutes a public health problem in most regions of the world
* New evidence suggests exposure to mercury may increase the risk of heart disease and stroke in men
* Increased mercury emissions from developing countries over the past 30 years have outstripped declines in the developed world
* Increasing mercury concentrations are now being detected in fish-eating wildlife in remote areas of the planet
Published: 08 March 2007
A worldwide warning about the risks of eating mercury-contaminated fish is to be issued by an international group of scientists today.
Three times more mercury is falling from the sky than before the Industrial Revolution 200 years ago, the scientists say.
Fish absorb the toxic chemical, which pollutes the seas, posing a risk especially to children and women of childbearing age. The role of low-level pollutants such as lead and mercury on the growing brain has been known for decades and measures have been taken to reduce exposure to a minimum. But the scientists say more must be done.
The warning is based on five papers by mercury specialists summarising the current state of knowledge on the chemical published in the international science journal Ambio. Called the Madison Declaration on Mercury Pollution, it presents 33 key findings from four expert panels over the past year. Every member of the four panels backed the declaration which was endorsed by more than 1,000 scientists at an international conference on mercury pollution in Madison, Wisconsin, in the US last August.
However, it runs counter to research by British scientists last month which found pregnant women who ate the most fish had children who were more advanced, with higher IQs and better physical abilities.
The British researchers said that while mercury is known to harm brain development, fish also contain omega-3 fatty acids and other nutrients which are essential to brain development. They studied 9,000 families taking part in the Children of the 90s project at the University of Bristol and concluded, in The Lancet, that the risks of eating fish were outweighed by the benefits.
The US scientists focused on the risks of mercury which they say now constitute a "public health problem in most regions of the world". In addition to its toxic effects on the human foetus, new evidence indicates it may increase the risk of heart disease, particularly in adult men.
While developed countries have reduced mercury emissions over the past 30 years, these have been offset by increased emissions from developing nations.
The uncontrolled use of the metal in small-scale gold mining is contaminating thousands of sites around the world, putting 50 million inhabitants of mining regions at risk and contributing 10 per cent of the global burden of the pollutant attributable to human activities in the atmosphere.
The global spread of the threat is revealed in increased mercury concentrations now being detected in fish-eating species in remote areas of the planet. The impact on marine eco-systems may lead to population declines in these species and in fish stocks.
Professor James Wiener, of the University of Wisconsin, said: "The policy implications of these findings are clear. Effective national and international policies are needed to combat this global problem."
In the US, official government advice is for pregnant women to limit their consumption of all seafood, including white fish, oily fish and shellfish, to no more than 12oz (340g) a week in order to limit their exposure to mercury.
In the UK, the Food Standards Agency advises expectant mothers to avoid shark, swordfish and marlin and to limit their consumption of tuna, because these are the fish with the highest levels of mercury.
The key findings
* Three times more mercury is falling from the sky today than before the Industrial Revolution
* Eating fish is the primary way most people are exposed to the toxic metal
* There is solid scientific evidence of the toxic effects of mercury on the developing foetus
* Mercury exposure now constitutes a public health problem in most regions of the world
* New evidence suggests exposure to mercury may increase the risk of heart disease and stroke in men
* Increased mercury emissions from developing countries over the past 30 years have outstripped declines in the developed world
* Increasing mercury concentrations are now being detected in fish-eating wildlife in remote areas of the planet
Born to die: Climate change disrupting life cycles with fatal results
By Terry Kirby, Chief Reporter
Published: 08 March 2007
The Independant Newspaper 08/03/07
The behaviour of Britain's wildlife is raising alarm about the seriousness of climate change as animals' breeding patterns are thrown into confusion. The second mildest winter on record has resulted in mammals, reptiles, birds and insects emerging from shelter far too early.
They are getting caught out by cold snaps or wet weather and the young of many species are dying. Baby hedgehogs, baby squirrels, even baby grass snakes are being found in distress in many places.
The disturbing trend is emerging as climate change once again moves to the political centre stage. The Government's long-awaited Climate Change Bill will be published next week, the Environment minister Lord Rooker announced yesterday. Delays in the preparation of the Bill have led to questions being asked about the Government's commitment to tackling global warming.
Opposition parties fear that the Government's proposals will not be specific enough, and have pressed for annual targets in carbon dioxide reductions.
The Environment Secretary, David Miliband, will go on the offensive over climate change next week. He will issue an undertaking to cut the UK's carbon output by between 15 and 25 million tonnes by 2020, although he will stop short of endorsing legally binding annual targets.
The visible impact on Britain's wildlife has manifested itself in the form of earlier than normal breeding, egg-laying, nesting and flowering of plants and trees, observed in British wildlife for more than 15 years and now linked to global warming in a whole series of scientific studies. They have sparked huge new interest in the discipline of phenology the timing of natural events.
But until now the changes have been seen as potentially harmful in the future, rather than the present. That situation seems to have changed this winter. One place with a remarkable overview is St Tiggywinkles wildlife hospital near Aylesbury in Buckinghamshire, which has been admitting large numbers of rabbits, grass snakes and other young animals suffering from the new ailment of being born at the wrong time.
A typical inhabitant is Bushy, as he has been named by staff, a 10-day-old grey squirrel, still blind and about four inches long. He is being bottle fed and even needs human help to make his bladder work, a job normally done by his mother, from whom he was separated when their nest was disturbed by tree cutters.
"He really should not be here. He was born two or three weeks before he should have been,'' says Les Stocker, the founder of Tiggywinkles. " This is the busiest year we have had for these kind of animals being brought in,'' he added. "The animals are becoming active and mating earlier than normal, but you can still get sudden cold snaps to which they are vulnerable."
Cold weather can either kill young animals or prompt them into hibernation, from which they do not awake because they lack sufficient fat reserves.
Toads and newts that should still be under a rock and pipistrelle bats which are normally still hibernating in hollow trees and barns have all been found out and about and there aren't enough insects around for them to survive on. The most unusual animals at the hospital are several edible dormice, so called because the Romans used to eat them. Not a native of this country, they are abundant in and around Tring in the Chilterns, where they have been breeding since escaping from a park 100 years ago. Ten times the size of a normal dormouse and looking more like a small squirrel, with a bushy tail, they normally don't emerge from hibernation until May.
Some baby birds have been brought into the hospital a blackbird and two ducklings. All are vulnerable to sudden cold spells. "Ducklings before Christmas is just crazy,'' says Lisa Frost, the research manager. She waves at the trees. "But you can see all the signs of nest building going on already.'' The mild winter is particularly confusing for hedgehogs. Baby hedgehogs are born in the autumn and the weaker ones weeded out by the first heavy frosts, ensuring the biggest are left to survive hibernation, when they rely upon their fat reserves. Warmer weather means that there are more weaker ones about who are not prompted into hibernating this makes them vulnerable to hazards such as sudden cold or wet spells. Ms Frost hauls one from its cage. "This one was brought in at the beginning of February, underweight and not eating. It was too small to hibernate and really should have died in the autumn."
Normally, Tiggywinkles would see only a handful of hedgehogs between January and March. This year it has had more than 80, on top of the 500 in the two months before Christmas, itself a 40 per cent increase. "It has been incredibly busy," said Ms Frost. "Usually this is a quiet period."
But Mr Stocker remains unconvinced about climate change. "If it is happening and I'm not sure that this hasn't all been hyped up I have great faith that nature will sort itself out and learn to live with it. After all, hibernation is a bad idea."
The global impact
* BIRDS
Migratory and breeding patterns have been thrown into confusion across Europe. Chiff-chaffs are remaining in the UK throughout the year rather than migrating south.
* FISH
Fish such as red mullet, once found only off Britain's southerly coastline, are now steadily being spotted further north, including the west coast of Scotland. Warm-water species such as tuna are being increasingly found by Cornish fishermen.
* TURTLES
Breeding grounds on beaches in the Caribbean and the Indian Ocean are under threat from rising sea levels. Water temperature affects the sex ratio, so warmer seas could mean some species becoming entirely female.
* POLAR BEARS
Their habitat of Arctic sea ice is melting away, while seals, their natural prey, are believed to be at risk from a decline in fish stocks. Polar bears are now thinner than 20 years ago.
* BUTTERFLIES
One study reports two-thirds of European butterflies have shifted their habitats north by between 20 and 150 miles.
Published: 08 March 2007
The Independant Newspaper 08/03/07
The behaviour of Britain's wildlife is raising alarm about the seriousness of climate change as animals' breeding patterns are thrown into confusion. The second mildest winter on record has resulted in mammals, reptiles, birds and insects emerging from shelter far too early.
They are getting caught out by cold snaps or wet weather and the young of many species are dying. Baby hedgehogs, baby squirrels, even baby grass snakes are being found in distress in many places.
The disturbing trend is emerging as climate change once again moves to the political centre stage. The Government's long-awaited Climate Change Bill will be published next week, the Environment minister Lord Rooker announced yesterday. Delays in the preparation of the Bill have led to questions being asked about the Government's commitment to tackling global warming.
Opposition parties fear that the Government's proposals will not be specific enough, and have pressed for annual targets in carbon dioxide reductions.
The Environment Secretary, David Miliband, will go on the offensive over climate change next week. He will issue an undertaking to cut the UK's carbon output by between 15 and 25 million tonnes by 2020, although he will stop short of endorsing legally binding annual targets.
The visible impact on Britain's wildlife has manifested itself in the form of earlier than normal breeding, egg-laying, nesting and flowering of plants and trees, observed in British wildlife for more than 15 years and now linked to global warming in a whole series of scientific studies. They have sparked huge new interest in the discipline of phenology the timing of natural events.
But until now the changes have been seen as potentially harmful in the future, rather than the present. That situation seems to have changed this winter. One place with a remarkable overview is St Tiggywinkles wildlife hospital near Aylesbury in Buckinghamshire, which has been admitting large numbers of rabbits, grass snakes and other young animals suffering from the new ailment of being born at the wrong time.
A typical inhabitant is Bushy, as he has been named by staff, a 10-day-old grey squirrel, still blind and about four inches long. He is being bottle fed and even needs human help to make his bladder work, a job normally done by his mother, from whom he was separated when their nest was disturbed by tree cutters.
"He really should not be here. He was born two or three weeks before he should have been,'' says Les Stocker, the founder of Tiggywinkles. " This is the busiest year we have had for these kind of animals being brought in,'' he added. "The animals are becoming active and mating earlier than normal, but you can still get sudden cold snaps to which they are vulnerable."
Cold weather can either kill young animals or prompt them into hibernation, from which they do not awake because they lack sufficient fat reserves.
Toads and newts that should still be under a rock and pipistrelle bats which are normally still hibernating in hollow trees and barns have all been found out and about and there aren't enough insects around for them to survive on. The most unusual animals at the hospital are several edible dormice, so called because the Romans used to eat them. Not a native of this country, they are abundant in and around Tring in the Chilterns, where they have been breeding since escaping from a park 100 years ago. Ten times the size of a normal dormouse and looking more like a small squirrel, with a bushy tail, they normally don't emerge from hibernation until May.
Some baby birds have been brought into the hospital a blackbird and two ducklings. All are vulnerable to sudden cold spells. "Ducklings before Christmas is just crazy,'' says Lisa Frost, the research manager. She waves at the trees. "But you can see all the signs of nest building going on already.'' The mild winter is particularly confusing for hedgehogs. Baby hedgehogs are born in the autumn and the weaker ones weeded out by the first heavy frosts, ensuring the biggest are left to survive hibernation, when they rely upon their fat reserves. Warmer weather means that there are more weaker ones about who are not prompted into hibernating this makes them vulnerable to hazards such as sudden cold or wet spells. Ms Frost hauls one from its cage. "This one was brought in at the beginning of February, underweight and not eating. It was too small to hibernate and really should have died in the autumn."
Normally, Tiggywinkles would see only a handful of hedgehogs between January and March. This year it has had more than 80, on top of the 500 in the two months before Christmas, itself a 40 per cent increase. "It has been incredibly busy," said Ms Frost. "Usually this is a quiet period."
But Mr Stocker remains unconvinced about climate change. "If it is happening and I'm not sure that this hasn't all been hyped up I have great faith that nature will sort itself out and learn to live with it. After all, hibernation is a bad idea."
The global impact
* BIRDS
Migratory and breeding patterns have been thrown into confusion across Europe. Chiff-chaffs are remaining in the UK throughout the year rather than migrating south.
* FISH
Fish such as red mullet, once found only off Britain's southerly coastline, are now steadily being spotted further north, including the west coast of Scotland. Warm-water species such as tuna are being increasingly found by Cornish fishermen.
* TURTLES
Breeding grounds on beaches in the Caribbean and the Indian Ocean are under threat from rising sea levels. Water temperature affects the sex ratio, so warmer seas could mean some species becoming entirely female.
* POLAR BEARS
Their habitat of Arctic sea ice is melting away, while seals, their natural prey, are believed to be at risk from a decline in fish stocks. Polar bears are now thinner than 20 years ago.
* BUTTERFLIES
One study reports two-thirds of European butterflies have shifted their habitats north by between 20 and 150 miles.
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