Friday, June 22, 2012

Is Clothianidin Killing The Honey Bees? Maybe, But Maybe Not

Photograph: Sean McCann, UF/IFAS Honey Bee
Research and Extension Laboratory
June 22, 2012 - Humans and their pesticides might be innocent - or not as guilty as thought - in the mystery of colony collapse disorder (CCD) that is causing a depletion of honey bee population worldwide. The evidence is not yet conclusive. Look it up on your favorite search engine, for example, and you'll find a number of theories and "explanations" as to the cause of the bees' dwindling numbers.

There is, to borrow a word from the panicky global warmists, no "consensus" yet about what the real cause - or causes - could be. Unlike the warmists, I am willing to be open minded and urge further research before we rush into banning certain pesticides. The theories range from virus-spreading mites, pesticides, pollutants and even chemtrails.

Consider this June 8, 2012 article at io9.com. It said that clothianidin, an insecticide sold in the USA, "disrupts the nervous system of insects, leading it to be a prime suspect in the mass death of honey bees. And just a few months ago we reported on a Science article reaffirming the suspicion that insecticides, particularly neonicotinoids, may be responsible. But new research coming out of Hawaii suggests that this may not be the case....It turns out that the parasitic Varroa mite - long known to torment honey bee populations - may be the culprit behind CCD. Or more accurately, it's the Deformed Wing Virus (DWV) that's being transmitted by these mites that's causing all the trouble."

The io9 article goes on to explain that the findings are not unique to Hawaii, and that CCD worldwide may be caused by the same mite-virus combination. "The research, which was conducted in Hawaii by researchers at Sheffield University, the Marine Biological Association, FERA and University of Hawaii, showed that Varroa increases the frequency of DWV in bee colonies from 10% to an astounding 100%."

There is still general confusion and disagreement among experts about the cause of CCD. Even so, that has not stopped some people from rushing to declare victory in the fight against it.

Consider this absurd headline from Reuters, for example: "Mystery of the disappearing bees: Solved!" Reuters's writer Richard Schiffman declared in his April 9, 2012 post that "Until recently, the evidence was inconclusive on the cause of the mysterious “colony collapse disorder” (CCD) that threatens the future of beekeeping worldwide. But three new studies point an accusing finger at a culprit that many have suspected all along, a class of pesticides known as neonicotinoids." Trouble is, some experts would say that the neonicotinoid family of pesticides (which includes clothianidin, thiamethoxam and imidacloprid) are not necessarily the cause of CCD. To wit, the Hawaiian study cited in the io9.com article above, which reports that Deformed Wing Virus, transmitted by the Varroa mite, is more to blame.

Curiously, Reuters ran another story on June 14, 2012 that contradicts Schiffman's declaration. "Bee populations have been falling rapidly in many countries, fueled by a phenomenon known as colony collapse disorder. Its cause is unclear but the Varroa mite is a prime suspect, since it spreads viruses while feeding on hemolymph, or bee’s 'blood'."

"Varroa mites reduce individual bee and colony vigor by feeding on their haemolymph," says a report from the College of Agricultural and Environmental Sciences at the University of Georgia. Haemolymph is the circulatory fluid of bees. "In addition, they vector viruses and facilitate infection by other bee pathogens."  The report cautions beekeepers that they should "Be aware that strong colonies in mid-summer can be highly infested with Varroa and even strong colonies can crash in population in late-summer and fall." There are ways to battle the Varroa mite, one being a bait-and-kill method that utilizes sticky boards and semiochemicals (natural chemical attractants). However, they are at best 35 to 50 percent effective in causing the mites to drop off of their bee host victims. (Watch a video of varroa mites infestation of mites inside the cells of a honeybee drone brood.)

Varroa mites cling to a bee pupa (more)
Varroa mites (varroa destructor can cause the destruction of a honey bee colony ("parasitic mite syndrome") is typified by the presence of "scattered brood, crawling or even crippled bees and unexplainable reduction of the bee population. The damage threshold however is not correlated with a fixed number of mites per colony."


The symptoms can vary, however, and can be influenced by factors such as bee and brood population of a particular hive or colony, the season "and the presence of bee viruses." Some of those viruses are known to be spread by Varroa mites.

Which to believe? I don't know, and a lot of experts are still uncertain as well. In Canada, pesticides are regulated by the Pest Management Regulatory Agency (PMRA). Better Farming recently reported that the president of the Ontario Beekeepers’ Association "says that the majority of dead honeybee samples tested by PMRA came back positive for clothianidin." 

Note: The "majority" of bees in the samples tested positive for clothianidin, not "all" of the bees. In other words, the samples tested did not provide conclusive evidence. It is compelling, yes, and certainly justifies further investigation and study, but if this was a criminal trial and clothianidin was the defendant, the jury would have to acquit because they would not be convinced beyond reasonable doubt.

Nevertheless, there are an awful lot of people currently screaming for the complete and immediate banning of clothianidin. If it is proven guilty, so to speak, then it should be banned. However, let's remember that the rush to ban the pesticide DDT a few decades ago has led to the death and utter misery of hundreds of millions of people worldwide who live in areas infested by malaria-carrying mosquitoes.

Even if clothianidin is the culprit in CCD, there could be mitigating circumstances: How clothianidin and other pesticides, for example, are distributeRachael Ludwick gives us a clue about this at r3431.com, where she cites a study that "describes how a pesticide — added as a seed-coating so that it will continue to work against pests as the plant grows — may be exposing bees to more of the pesticide than expected. This is extremely interesting to me because a major advantage of seed-coating is that it reduces environmental exposure. Relatively small amounts coat the seed and they are translocated throughout the plant as it grows, ideally only affecting pests that eat the plant itself." Ludwick also wrote, "the pesticide-coated seeds have to be coated in talc before planting to keep from jamming the equipment. The residue talc and dust was contaminated with pesticide ....which they postulate could be falling on other flowers that bees forage on which the authors see as a significant risk of exposure."

Ludwick then surprises her readers by cautioning against rushing to ban clothianidin. "You might think from reading this that we should ban this pesticide immediately. But that seems premature to me. First, the authors themselves note that better handling of talc and dust residues could remove 99% of the risk from that exposure route."

Despite calmer advice from people such as Ludwick, a flurry of hurry-up-and-ban activity is taking place. The panic-stricken Beyond Pesticides, a grouping of "beekeepers and environmental groups," has presented a petition to the Environmental Protection Agency. They claim to have "over 1 million citizens" who have signed a petition to "urge [the] EPA to suspend use of pesticide that kills bees." While I respect these people in their effort to get the government to consider the potential dangers of clothianidin, they should really not be taken seriously.

While their petition cites a lot of studies, we've seen here that there are many other studies that indicate that clothianidin may not be the culprit, or the only culprit, that is causing CCD. It is somewhat odd that the people behind the petition give no credence whatsoever to the possibility that anything other than clothianidin (and related neonicotinoid pesticides) could be killing bees. They make no reference to the Hawaiian study, and they certainly don't mention chemtrails. (I wonder if anybody at Beyond Pesticides sees the irony of that, considering the name of their organization.)

I am not an apologist for the makers of any insecticides. Nor am I saying that clothianidin is harmless. It's just that from reading a lot of the literature out there, from a wide variety of opinions, there is general confusion. Accusation are flying against GM corn, against nicotine-based pesticides, against mites, some blame climate change, many blame a combination of some or all of the above. Another thing to consider: There is very, very strong evidence that the parasitic Varroa mite is a prime suspect in CCD. For the eco-imperialists, however, the mite does not fit into their political agenda. 

IF clothianidin is the culprit, then ban it. But I would hate to see what may be a useful pesticide banned unnecessarily and - worse yet - have attention diverted from the  Varroa mites, the true villain in the story. We still have time.

And, finally, some "good" news: Even if all the bees went extinct tomorrow, we would NOT starve, no sir, because the vast majority of our non-animal food sources do NOT depend upon pollination for reproduction. Einstein is said to have warned that if all the bees died out, humans would starve to death four years later. Fortunately, this is simply not true (and there is even some doubt that Einstein even actually said that). Bees are not the only insects that act as pollinators. That being said, it would cause us to lose a number of beloved agricultural products, but would not mean the extinction of homo sapiens. Not even close.

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