Monday, November 15, 2010

A Cause of the Honey Bee Deaths

My bees died this spring. They had been healthy and happy 5 days prior when I had put an essential oil in their hive to kill off mites. Something I do every spring and not something that would harm them. However, 5 days later I was walking by the hive, I noticed hundreds of dead bees at the doorstep to the hive and on the ground in front of the hive. I looked inside and most of the rest were in various stages on their way to death. The ones still alive appeared to be drunk. I thought they looked like they had some sort of nervous system toxicity.

When I called my local bee association and spoke with one of the respected mentors there. He told me he thought my bees had a new type of Nosema called Nosema ceranae. I got my microscope out and dissected some bees and did see the Nocema spores. However, with ceranae the bees usually die away from the hive and what I had was a massive amt of dead bees (appeared to be all of them) in the hive or right outside of the hive. Plus the ones still alive looked drunk. I was so sure they were poisoned with something.

Upon further investigation I came upon what I think was the culprit. A type of insecticide called imidicloprid. It is my personal belief that this insecticide is a main cause of the massive honey bee deaths being experienced on the planet.

In 2003, 13 North Dakota beekeepers brought a class-action lawsuit against Bayer, alleging that the company's neonicotinoid, Imidacloprid, which had been used in nearby fields, was responsible for the loss of more than 60% of their hives. The beekeepers said their bees appeared to be getting drunk from the spray. They could not walk straight and could not work. (Just like mine!)

Dr. Daniel Mayer a retired bee expert from Washington State University, traveled to 17 different bee yards in North Dakota and observed dead bees and bees in the throes of what looked like Imidacloprid poisoning. He theorized that after foraging in planted fields where the seeds had been treated with Imidacloprid, the bees then brought the pesticide back to the hive, where it built up in the wax combs.

Pennsylvania beekeeper Dave Hackenberg lost 60% of his colonies. In an interview with Linda Mounton Howe, he said hat he and other beekeepers thought the culprits were systemic nicotine-based insecticides getting into crops that flower, contaminating the pollen on which honeybees forage. Imidacloprid (Called Gaucho by Bayer is a nicotine-based insecticide.)

Many of us beekeepers think that the virus and fungi that are being found in the bees guts when they are found dead (colony collapse disorder) is not the actual culprit but they are merely opportunists growing out of control in bees with compromised immune systems. People have asked what is it that is suppressing the bee’s immune systems. Why do so many of the bees die in the fields and not even return to their hives. Some of us think the answer is Bayer’s number one selling insecticide, Imidacloprid. Imidacloprid is s neonicotinoid that lab tests have confirmed will interfere with nerve impulse transmissions in insects, including honeybees. Aha, this sounds like a drunken honeybee does it not?

Environmental groups and beekeeper organizations have been trying to ban neonicotinoid pesticides, which have been linked to bee decline across the world. In a recent study, the toxicity of neonicotinoid insecticides to arthropods was shown to be reinforced by exposure time. The Dutch toxicologist Henk Tennekes demonstrates that the long-term risks associated with the insecticides imidacloprid and thiacloprid are far greater than previously thought. This could actually explain worldwide bee decline. The study was published in the journal Toxicology, July 23rd.

The acceptable limits for neonicotinoid insecticides are based mainly on short-term tests. If long-term studies were to be carried out, far lower concentrations may turn out to be hazardous. This explains why minute quantities of imidacloprid may induce bee decline in the long run.” Because of their high persistence significant quantities of neonicotinoids may remain in the soil for several years. Consequently, untreated plants growing on soil previously exposed to imidacloprid may take up the substance via their roots and become hazardous for bees.

In short imidacloprid and other neonicotinoids are bad news for the bees and probably bad news for other beneficial insects. Some countries such as France and Germany have bans on neonicotinoid use. Bayer has had multiple law-suites against their product imidacloprid, but in the USA we are still using it along with its closely related chemical relative called clothianidin (also made by Bayer)

WHAT CAN WE DO? I am sure none of you reading this blog use toxic chemicals in your gardens or on your farms. However, we need to talk to our neighbors and find out what they use. Educate them on the hazards of neonicotinoids. It will take all our efforts to save the honeybees.

Places you can learn more: