Love them or fear them, honey bees are a major player in the agricultural industry. Best known for making the delectable honey that mixes so well with peanut butter and sweetens tea, these buzzing insects are also responsible for maintaining crops such as almonds, blueberries, avocadoes and pumpkins. Their contribution to our economy is immense, amounting to close to 10 per cent of the global food industry, an incredible $200-billion.
For centuries, bees have been a steady part of agriculture. However, in the last decade, due to a rather pesky germ and modern day crop management, this stability has been threatened. What's worse is that the impact could lead to less choice at the grocery store and inevitably higher prices.
Since the late 1800s, there has been one specific problem associated with beekeeping in which the colony seems to lose its ability to thrive and eventually dies. Originally called 'bees evaporated' this phenomenon is now known as colony collapse disorder, or CCD. The effect of CCD is akin to witnessing the ravages of war on the losing side. The worker bees, the queen's army, all but disappear leaving her to fend for herself. Sadly, without her helpers, she too is doomed. Eventually, the colony is lost.
In 2006, after a sudden increase in CCD, researchers went on the hunt to see if there was a cause. Their first suspects were germs known to cause problems in bees. Several were found, but one particular microbe became a major target. The name was Nosema, a small single-celled parasite known to cause colony problems in the past. But as researchers took a closer look at how this parasite went from casual annoyance to all-out bee terrorist, an incredible web of information was revealed showing that the real problems were not natural at all.
One of the trademark problems associated with any parasitic infection is the lack of an appropriate immune response. Because Nosema has been known to infect immunocompromised humans, researchers decided to look at whether there were any problems with bee immunology.
In 2011, a collaborative group of agricultural researchers from Japan and China tested this hypothesis and found that problems with immune function led to increased Nosema infections. Their claim was that the overall nature of beekeeping was causing undue stress on colonies leaving them prone to infection and collapse. But the results could not explain all cases as even those who kept bees in the least stressful means were experiencing problems.
This led to another theory that perhaps it was another human intervention causing the problem. While the testing could offer an answer to the problem, if the suggestion was correct, the plight of bees might become almost unstoppable.
A year earlier, in 2010, a group from the French National Institute for Agricultural Research (INRA) had already published a study showing bees could have a reduced immune system when exposed to low levels of a particular insecticide known as imidacloprid, which is part of a larger group of pesticides known as neonicotinoids. In agriculture, this chemical is important to prevent crops from being infected with a variety of pests and has been in use for close to 20 years without any concern. However, due to this study, the effects of the chemical on bees and infection became a priority.
A number of studies followed and revealed that there was indeed a link between higher levels of infection and chronic exposure to pesticides and not only the neonicotinoids. The reports appeared to be conclusive, but there had yet to be a true field study to show that the work in the lab was actually happening in the real world.
This week, that gap was filled by an American collaboration led by Dr. Dennis vanEngelsdorp at the University of Maryland. In the study, pollen was collected from fields across the U.S. continent and tested for the presence of insecticides. In all crops except almonds, they found residues that were high enough to cause the bees significant problems.
Back at the crop laboratory, bees were given the chance to collect either the gathered pollen grains or pesticide-free grains and bring them back to the hive. The bees were then fed Nosema and as expected, infection occurred in almost twice as many bees as those not exposed to the pesticide-laden pollen. To confirm the link even further, the likelihood of infection was directly related to the amount of pesticide found on the grains.
While the puzzle of CCD may be solved, the resolution of the problem presents much greater challenges. The likelihood of banning such pesticides is low to nil while offering protected crops for bees alone would be costly and almost impossible to sustain. Earlier this year, the United States Department of Agriculture released a report on the issue of declining bee populations with a series of recommendations to help improve the situation. Unfortunately, while they all agreed that something must be done to improve bee health, there was little done other to suggest a series of priorities to be addressed over the coming decade.
In the meantime, there is a significant risk that the problem will grow worse over those years and could put our food security at risk. There are options to prevent the collapse of the bee-generated agricultural industry, including the invention of robot bees; however they may do little to help these yellow and black striped marvels. Without more immediate action to lessen the burden on these insects, there is a chance that we could be seeing less of them and as a consequence, less at the grocery store and your dinner table.