Vanishing honeybees

Extracts from
Bees Vanish, and Scientists Race for Reasons
By Alexei Barrionuevo for the New York Times, April 24, 2007
BELTSVILLE, Md., April 23 — What is happening to the bees?

More than a quarter of the country’s 2.4 million bee colonies have been lost — tens of billions of bees... So far, no one can say what is causing the bees to become disoriented and fail to return to their hives.

As with any great mystery, a number of theories have been posed, and many seem to researchers to be more science fiction than science. People have blamed

• Genetically modified crops
  
• Cellular phone towers
  
• High-voltage transmission lines for the disappearances. Or was it
  
• A secret plot by Russia or Osama bin Laden to bring down American agriculture? Or, as some blogs have asserted,
  
• The rapture of the bees, in which God recalled them to heaven?

Researchers have heard it all.

"Colony collapse disorder" [is] the name given for the disappearing bee syndrome.

The most likely suspects: a virus, a fungus or a pesticide.

Genetic testing at Columbia University has revealed the presence of multiple micro-organisms in bees from hives or colonies that are in decline, suggesting that something is weakening their immune system. The researchers have found some fungi in the affected bees that are found in humans whose immune systems have been suppressed by the Acquired Immune Deficiency Syndrome or cancer.

So far, colony collapse disorder has been found in 27 states... A recent survey of 13 states ... showed that 26 percent of beekeepers had lost half of their bee colonies between September and March.

Honeybees are arguably the insects that are most important to the human food chain. They are the principal pollinators of hundreds of fruits, vegetables, flowers and nuts. The number of bee colonies has been declining since the 1940s, even as the crops that rely on them, such as California almonds, have grown.

Bee colonies have been under stress in recent years as more beekeepers have resorted to crisscrossing the country with 18-wheel trucks full of bees in search of pollination work. These bees may suffer from a diet that includes artificial supplements, concoctions akin to energy drinks and power bars. In several states, suburban sprawl has limited the bees’ natural forage areas.

... Researchers emphasized today that feeding supplements produced from genetically modified crops, such as high-fructose corn syrup, need to be studied.

Mr. Hackenberg, the beekeeper, agreed to take his empty bee boxes and other equipment to Food Technology Service, a company in Mulberry, Fla., that uses gamma rays to kill bacteria on medical equipment and some fruits. In early results, the irradiated bee boxes seem to have shown a return to health for colonies repopulated with Australian bees.

"This supports the idea that there is a pathogen there," Dr. Cox-Foster said. "It would be hard to explain the irradiation getting rid of a chemical."

Still, some environmental substances remain suspicious.

Of greatest interest are the "systemic" chemicals that are able to pass through a plant’s circulatory system and move to the new leaves or the flowers, where they would come in contact with bees.

One such group of compounds is called neonicotinoids, commonly used pesticides that are used to treat corn and other seeds against pests. One of the neonicotinoids, imidacloprid, is commonly used in Europe and the United States to treat seeds, to protect residential foundations against termites and to help keep golf courses and home lawns green.

In the late 1990s, French beekeepers reported large losses of their bees and complained about the use of imidacloprid, sold under the brand name Gaucho. The chemical, while not killing the bees outright, was causing them to be disoriented and stay away from their hives, leading them to die of exposure to the cold, French researchers later found. The beekeepers labeled the syndrome "mad bee disease."

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