There has been a lot of talk about pesticides and GMOs and their impact on bee health. Apocalyptic predictions are being made about the effect of insecticides on bees, claiming that farmers and chemical companies are the cause of reduced bee numbers. As a farmer that uses these products, I feel that it is important to get to the bottom of this issue, separate fact from fiction, and understand if these claims are legitimate. I think you’ll find, as I did, that the hype about bees and pesticides is just that- hype.
For nearly the past eight years, bee health has been a pressing issue in the news. When severe colony collapses were first noted in 2006, a flurry of finger-pointing ensued, with blame pointed at disease, mites, viruses, and, of course, genetically modified crops and pesticides. Recently, the discussion has shifted specifically to seed treatments, and the theory that they are responsible for this so-called colony collapse disorder. Governments have been quick to begin talks of banning these insecticidal seed treatments, and in some parts of the European Union, bans have already taken place. Is this simply a government being prudent, or are they going too far, too fast? First, I have to get through some sciency stuff, so we’re all on the same page.
What are neonicotinoids?
Neonicotinoids (I’ll call them neonics from here on) are a class of insecticidal chemicals that we use quite regularly, both as seed treatments and as foliar insecticides. Their main use is in seed treatments, which are applied to all canola and soybean seed that we buy, and which we also apply to most of our wheat, durum and barley. They are also found in the seed treatments used on corn. Sometimes, we need them to kill pests after crop emergence, particularly in canola, where flea beetles can be very damaging.
Insecticides are pretty straightforward in nature; they are used to target insect pests that affect our crop. Some of them are pretty nasty. There were some old chemistries out there that were rather toxic, and were generally bad for the environment. As time went on, newer and better chemistries evolved that became safer, cleaner, and more targeted to a specific class of insects. Neonics were a breakthrough when they were first introduced, with benefits including low application rates, low toxicity for mammals, good systemic movement in plants and a variety of application methods.
Let me quickly run through the very basic biochemistry of how neonics work: they bind to nicotinic acetylcholine receptors of a cell within the central nervous system, triggering cellular stimulation. Low to moderate stimulation of these cells is quite normal, but neonics bind at high enough levels to overstimulate and block these receptors, causing paralysis and death. In mammals, they don’t bind nearly as strongly, and as a result are much less toxic (that wasn’t so bad, was it? If you want more information, you can find it here).
Do neonicotinoids affect bee health?
I guess this is the billion-dollar question, right? The answer is not as simple as you might think. So far, the research has shown wildly different results when subjecting bees to acute (one-time) doses of neonics. Sensitivity to these chemicals varies with the test bee’s age, subspecies, nutrition, physiological condition, and handling during testing, in addition to the season that the testing was performed in. A vital detail of most of these studies is that they were performed in a laboratory setting. Interestingly, when testing outside of the lab, the same results were not found. Bees are incredibly complex organisms, and it seems that their gut microbiota changes drastically when grown in the wild, which changes their tolerance to insecticides.
The losses that beekeepers are sustaining have been at their worst in fall and winter; the time of the year when neonic seed treatments are not being applied. Conversely, during spring and summer, bee losses are minimal; and, since bees really only live for about a month at a time, carryover of toxins from spring to winter is extremely unlikely.
I think it is safe to say that high doses of insecticides of any kind are dangerous for bees. The same could be said for mammals, including humans. In fact, all kinds of chemicals that we use every day are toxic for humans. Alcohol, caffeine, aspirin, vinegar; they are all toxic substances in a high enough dose. The dosage makes the poison. A high enough dose of just about anything can be deadly. When you look at the results of good quality, peer-reviewed scientific literature, the results are pretty clear: neonicotinoids are not responsible for colony collapse disorder.
How are GMOs connected?
This is a misconception that is far too persistent in the public eye. There is a belief that GMOs are also responsible for colony collapse disorder, and that neonicotinoids and GMOs are connected. This is quite simply not true. In fact, the reality of the matter is that GMOs are not connected to bee deaths. Even if neonics were wholly responsible for colony collapse disorder, GMOs have little to do with their usage. Sure, I’ll grant that GM corn, soybeans and canola have been very popular, and that they are all coated with a neonic seed treatment. But, so are a great deal of wheat, durum, barley and oat acres, in addition to crops like peas and lentils. Even if we did not have genetically modified crops, we would still treat most of our main crops with an insecticidal seed treatment.
The genetic modifications present in our GM corn, soybeans and canola also do not affect bees. In fact, bee numbers in Western Canada, where canola is grown on nearly 20 million acres, are actually climbing. Canola yields have even been shown to improve with high numbers of bees available. The bee losses in Eastern Canada, and other areas, are caused by other factors, as you’ll see next, and are not nearly as bad as you might have heard.
So what’s killing the bees?
There are many factors involved with colony collapse disorder, but the most significant cause of increased bee mortality in the last few years has been the varroa mite. They suck blood out of bees and inject viruses, and they are so large in relation to bees that they are very dangerous to them. Miticides used to control the varroa mite have had mixed results, with constant resistance developing in the mite, reducing control. Furthermore, some of the miticides used are proving to be quite toxic to the bees themselves.
Fungal disease has been another cause of bee mortality, with a disease called Nosema being particularly damaging. Inadequate nutrition, improper hygiene and other diseases and mites are other damaging factors that have been affecting bee health.
Certainly, there is evidence that neonicotinoids have been hurting bees. The biggest problem has been the dust from planters, which when deposited at field edges from wind, can become quite concentrated. However, this issue is becoming quickly overcome with better planter technology and improvements in the powders applied with the seed to reduce dust. Indeed, the response from chemical companies and equipment manufacturers to reduce this toxic dust has been outstanding thus far, with fantastic improvements over only the past couple of years. They are taking this issue very seriously.
The stakes are high
Bees are responsible for pollinating more than $200 billion of agricultural crops worldwide. They are an absolutely vital part of our world’s ecosystem, and it is paramount that we discover why colony collapse disorder occurs. However, throwing blame on pesticide manufacturers is thus far unfounded. Unfortunately, it is a popular political position to take, as evidenced by the two-year ban in Europe and the Ontario government’s plan to reduce neonic use by 80% by 2017.
The fact is that we need these insecticides. Without neonicotinoids, we will have to go back to reliance on old, persistent, dangerous insecticides that could cause other significant environmental problems. An example of this is in Europe, where neonics have been banned. They are resorting to old, pyrethroid insecticides to control flea beetles in their rapeseed (much like canola) and are having substantial crop losses. Widespread resistance to these old insecticides is a major issue. Farmers are spraying for flea beetles without even knowing if the insecticide will kill them! Without neonics, we would quickly run into the same problems here.
On my farm, we use neonicotinoids for a reason- to grow crops. Without them, canola would be an extremely challenging crop to get established, and we would be using a lot more older, more dangerous insecticides to save them. Wireworms would have a significant impact on wheat production as well. In other regions, corn and soybean would suffer significant losses from other early-season insects.
At this stage, a ban is completely the wrong move. Governments need to base their decisions in science, not in the voices of a vocal minority. Farming is a difficult business, with a myriad of challenges that face us throughout the year. Right now, good pollination by bees simply is not a problem. Flea beetles, wireworms, soybean aphids, and a variety of other pests are all suppressed and/or controlled by current neonic seed treatments. Banning them on weak science will only cost farmers more money and hurt the environment. Is this the result we really want?
Note: I found a lot of great articles on this subject as I researched it. Check out the links below to read more. My article only scratches the surface of this issue.
Cutler, G.C. 2007. Exposure to Clothianidin Seed-Treated Canola Has No
Long-Term Impact on Honey Bees. Entomological Society of America.
Entine, J. 2014. Bee deaths and neonics: Inside story of Colony Collapse Disorder, Harvard’s Chensheng Lu’s crusade. Genetic Literacy Project.
Fairbrother, A., et. al. 2014. Risks of Neonicotinoid Insecticides to Honeybees. Environmental Toxicology and Chemistry.
Farmers Weekly. 2014. Flea Beetle ‘Epidemic’ Spurs Call For Neonic Return.
Gervais, J. A.; Luukinen, B.; Buhl, K.; Stone, D. 2010. Imidacloprid Technical Fact Sheet; National Pesticide Information Center, Oregon State University Extension Services.
RealAgriculture.com. 2014. OMAFRA & MOECC Announce Plan to Reduce Neonic Usage by 80% by 2017.
Simon-Delso, N. et. al. 2014. Systemic insecticides (neonicotinoids and fipronil): trends, uses, mode of action and metabolites. Environmental Science and Pollution Research.
Terry Daynard’s Blog (There are a few great posts on this subject that really explain bees and neonics well).