One of the most important crop pollinators in the world, honey bees in the United States have been decimated in recent months by a mysterious disease.
Credit: Jon Sullivan/Wikipedia
The almond trees are blooming and the bees are dying, and nobody knows why. All up and down California's vast San Joaquin Valley, nearly 2,500 square kilometres of small nut trees arranged in laser-straight rows are shaking off the cobwebs of winter. They're gearing up once again to produce nearly half a billion kilograms of nuts, worth US$3 billion to the U.S. economy.
The trees cannot produce the bounty on their own, however. They need bees - a million hives worth - trucked in from nearly forty U.S. states to move pollen from one tree to another, fertilising the blooms in the largest managed pollination event on Earth.
But even as the beekeepers reap record fees for renting their hives, their livelihood is now threatened by the largest loss of honey bees in the history of the industry.
Since October 2006, 35 per cent or more of the United States' population of the Western honey bee (Apis mellifera) - billions of individual bees - simply flew from their hive homes and disappeared.
When the almonds were being plucked from the trees late last year, Gene Brandi of Los Banos, California had 2,000 hives, but by late February he had just 1,200 - a loss of 40 per cent.
And Brandi is one of the more fortunate. Across the 24 U.S. states affected by the mysterious phenomenon, losses have ranged up to 90 per cent. "I've had a couple of yards where I've had 200 hives and they're down to 10 hives that are alive," says David Bradshaw of Visalia, about 180 kilometres southeast of Los Banos along California's Route 99.
What's causing the carnage, however, is a total mystery; all that scientists have come up with so far is a new name for the phenomenon - Colony Collapse Disorder (CCD) - and a list of symptoms.
In hives hit by CCD, adult workers simply fly away and disappear, leaving a small cluster of workers and the hive's young to fend for themselves. Adding to the mystery, nearby predators, such as the wax moth, are refraining from moving in to pilfer honey and other hive contents from the abandoned hives; in CCD-affected hives the honey remains untouched.
The symptoms are baffling, but one of the emerging hypotheses is that the scourge is underpinned by a collapse of the bees' immune systems. Stressed out by cross-country truck journeys and drought, attacked by viruses and introduced parasites, or whacked out by harmful new pesticides, some researchers believe the bees' natural defences may have simply given way. This opens the door to a host of problems that the bees can normally suppress.
What's surprising is that mysterious declines are nothing new. As far back as 1896, CCD has popped up again and again, only under the monikers: 'fall dwindle' disease, 'May dwindle', 'spring dwindle', 'disappearing disease', and 'autumn collapse'.
Even the current outbreak has possibly been going on undetected for two years, according to the CCD Working Group - a crack group of U.S. researchers from institutes including the Pennsylvania State University and University of Montana, who are trying to unravel the mystery.
What has made the members of the Working Group - as well as conservationists, beekeepers, and farmers - really sit up and notice is the scale of this year's decimation; something in the environment has allowed CCD to reach an unprecedented scale that threatens the very survival of the pollination industry.
"We have never seen a die-off of this magnitude with this weird symptomology," says Maryann Frazier, a bee researcher at Pennsylvania State University. "We've seen bees disappear over time and dwindle away, but not die-off so quickly."
Asian mites and latent viruses
A problem preventing clear identification of CCD is that honey bees are already under threat from manifold foes.
Even without CCD, the number of managed hives in the U.S. has dwindled by nearly 50 per cent since the industry's peak in the 1970s. The main culprit for the die-offs is a tiny Asian mite. Known as Varroa destructor to scientists and the 'vampire mite' to beekeepers, these tiny parasites - circular, crab-like arachnids about the size of a bee's eyeball - have been quietly parasitising the Asiatic honey bee (Apis cerana) in Southeast Asia for millennia.
 |
|
Varroa destructor, a tiny tick-like arachnid, has been wreaking havoc on U.S. honey bees since it was inadvertently introduced from Asia in the 1980s.
Scott Bauer/Wikipedia
|
Some time in the early 1980s, though, the mites hitched a ride to America and hopped on new hosts - spreading like wildfire throughout the defenceless Western honey bee population with the help of migratory beekeepers who obligingly trucked them around the country. The mites suck the vital juices out of both developing and adult bees, and left unchecked can kill a hive within 12 months.
In addition to the damage that the mites do themselves, they also spread viruses. Furthermore, the mites appear to assist the viruses by somehow sabotaging the bees' immune system.
"There's something about a mite feeding on a bee that just knocks its immune system out. [Then] the viruses can take over," says Eric Mussen, a bee researcher at the University of California, Davis.
But mites and their viruses have been infecting U.S. honey bees for nearly 30 years. What has experts worried is that CCD kills bees even more efficiently than mites - destroying a healthy colony in a matter of weeks.
Effects of carbon dioxide narcosis.....
The death of the bees is a common factor of phenomenon related to the topic under discussion but the factors that have an influence on the dyings of the bees might vary a lot depending on a case involved. Some factors cause the death of the bees straight away (viruses, toxins, bacteria, fungi, mites, the end of natural age, accidents, killing, natural enemies etc). Some factors contribute to death of the bees (stress, malnutrition, fast climate changes, manipulation of the productivity of bees or maybe gene manipulation of bees if it exists, etc). Some factors will increase probability more or less to get them hurt and die. All things interrelate all things and there for, I suppose, the causality of the death of the bees is very difficult to find out exactly. Biological systems are very complicated and complex. However, in an inbalanced circumstances when CO2 is too much involved the balance of life is threathened. CO2 is a remarkable factor in modifying the community structure of the bees. The bees and other insects have genes that react very sensitively to CO2 content changes modifying gene expression to certain direction in their indivual physiological development. I'd like to refer to a paper that introduces how CO2 narcosis of bees effects on ovary activation and experession in worker honeybees, Apis mellifera. You can call it up the web site. It has been published in Journal of Insect Science, 2005.5:36 (18 Nowember 2005). http//www.insectscience.org/5.36/
Raino Pietarinen
more on the bees
I agree with the person from Finland. The probable causes could be numerous and varied. However I suggest also that CO2 as an Oxygen reduction agent be further investigated. There are also other sources of O2 reduction in the air such as N2, or other gasses, but not as prevelent as the CO2. I am in the process of identifying sources of gasses which might reduce O2 in the air in additon to the ones which I have already identified. Other obvious sources are as follows:
1. Automobile emissions.
2. Biomass sources such as compost sources.
3. Volcanoes.
Comments of other sources are obviously welcomed.
Lionel Milberger
Less Oxygen due to deforestation, droughts and forest fires
In a global scale Oxygen is produced by vegetable kingdom through the prosess of photosynthesis. Every day extremely huge amount of Oxygen is bound in an oxidizing reactions with minerals that can be oxidized as carbon, hydrogen, sulfur, nitrogen, iron etc. and other oxidizing materials. On the earth six billion people and a huge amount of animals, insects and microbes breath oxygen and exhale carbon dioxide. A person exhales almost a 1000 kgs CO2 in a year and a car's CO2 emissions are four times higher than an individual in a year.
Fortunately, we have many kind of plants, in other words, our vegetable kingdom producing oxygen to inhale. But what we see on earth today. Deforestation in earth's lungs, in rain forests all over the world has been continous and increases all the time. In Asia, in Africa, in central America and in USA there have been forest fires in the spring. More CO2 and less O2 within and around the area of forest fires. The part of South Africa has suffered drougts which collapses oxygen production in this area for the time being. For the good reason the oxygen productive systems have been damaged by the action of people on the earth.
Statiscally the emissions of methane, one of the greenhouse gases, have also increased a lot in last few decades due to agriculture and waste production. What can the climate warming do to methane producing prosesses in swamps areas? Are the swamps probably accelerating their methane production. In the areas of ancient frozen ground in Siberia and Alaska melting of soil could release methane emissions into the athmosphere. It is generally known that frozen areas that contain methane in large scale are in Siberia and in Alaska. I do not know exactly how does methane gas will behave with oxygen in the air but if it will be emitted in large streams it will partly replace oxygen suffocating people, animals and insects in the streaming area.
What kind of effects on oxygen levels in the air have garbage dump areas? Density populated cities produce an immense amount of garbage, that decomposes minerals, CO2, methane and other compounds in certain time period. Could it be possible that the emissions of garbage dump emit above mentioned compounds in intervals but not continously due to climate warming in the spring causing intervally increased levels of life treathening gas streams around.
In a global scale the levels of oxygen in the air depends on compounds to which it is bound and at the same time how much vegetable kingdom can it release in the air during photosynthesis.
It is very important to take good care of our planet because it is much more stronger than human kind. Although human kind is getting the planet out of balance by damaging the nature of the earth. Basically, who is the winner? Would it be time to plant a tree for tomorrow?
Some thougts to be discussed furher.
Raino Pietarinen
Low O2 in air
I agree with all your major thoughts. Just for information, using your emissions rate for a human of 1000 kg/year for CO2, the Amine Gas Plant near our house (based on permited amount) emits CO2 equal to 153,000 people!! It's really pouring it out!! Could that explain why we and others are getting sick around here?
Lionel Milberger
Amine Gas Plant CO2 load equals ca 40.000 cars' CO2 load a year
The CO2 emissions of people exhaled are derived from renewable sources but power plants and traffic made CO2 load is derived from fossil fuels and that's very bad thing and needs global agreements of the restrictions of CO2 emissions all over the world. I am sorry for you living there within emissions. Policymakers have to wake and do something for the best of the earth. Of course everybody can do something too but it is not enough if somebody does't.
Raino Pietarinen
More on CO2 in the air
I wish to point out that CO2 can dissolve in water and carbonic acid can be formed. Around large emission sources of CO2 (such as already mentioned), could the bees (and other species for that matter) be injesting CO2 and carbonic acid laden dew drops or other water sources? Is there any way to test for PH of the water that was taken in by the sick and dead bees? Comments are obviously invited.
Lionel Milberger
Testing pathologies of bees
I am not an expert of lab tests but I found a person who might be an excellent expert of bee pathology. She is Professor Department Entomology, Diana Cox-Foster from The Pennsylvania State University. She is a representative of colony collapse disorder working group. She has over 25 years experience in insect physiology, pathology, molescular biology and evolution. She has active experience in disease biology through involvement in biodefence issues in agriculture. I am sure you'll get some help from her.
Raino Pietarinen
dying bees
Interesting , I understand that GMO corn pollen could be to blame. You see this GMO plant produces a toxin to prevent pests from wreaking havoc on corn plants.
Maybe if we correlate corn fields to this bee problem it could prove usefull. If this doesn't get repaired soon we WILL run out of food!
dying bees
I am in the field of alternative health and one of things that has caused an increase in weaknesses in the human defense system is electromagnetics. Could this also be a factor in the death of bees? I especially like the theory of the GMO corn pollen. Corn is toxic to eat these days - it is no longer the same stuff our grandparents used to eat. The same goes for wheat.
That is my two cents worth.
Bees dropping from flowering pear tree in Clovis, Calif.
My neighbor has a flowering Bradford Pear tree in the front yard and another variety, maybe an Aristocrat Pear. While the tree was in bloom recently she noticed that dozens of bees were just falling to the ground and landing dead in her driveway. Since then she says she's been sweeping them up every day and they are still dying even though most or all of the blossoms are gone now. My huge evergreen Kawakami Pear in my front yard had lots of bees on it, when it was in bloom, and NONE were found dead in our yard. It had to be something about the the neighbor's blossoms that killed them so suddenly, not anything in the air all over the city. Her trees have NOT been sprayed, which is what the Ag Dept told her it must be. They weren't even interested in coming out to investigate, and this area depends on bees to pollinate the many varieties of fruit trees in the valley. Other folks at this site have noted that the bees just dropped out of the bushes or trees. How can one explain that? It's like the trees and shrubs have a disease or infection that instantly kills them, but it's NOT a pesticide.