Two new studies published in late March hope to explain, at least partially, the issue of disappearing bees. This phenomenon also known as colony collapse disorder (CCD) is a major issue for people who rely on these pollinators to produce food – i.e. everyone.
CCD has been around throughout history, but the number of colonies affected were always very few. Starting in 2006, the number of wild bee colonies affected increased dramatically in the United States; it was later discovered that there was evidence of such issues found in Europe and some parts of Asia.
The reason for the sudden jump in CCD has been attributed to a number of things. Some experts blame cell towers, claiming that they interfere with bees’ ability to find their way back to the hive after they leave, preventing them from returning home until no bees are left but the queen. Another possible cause for CCD is thought to be natural, such as a particular species of mites or a virus that jumps from colony to colony. A more recent focus has been given to a certain type of pesticides neonicotinoids; these pesticides are taken into a plant through its roots and coat its cells with a toxic poison, until the point where even its nectar is contaminated, though in much lower quantities than the rest of the plant.
The two studies published in late March examine the impacts that neonicotinoids have on bees in low quantities. The results were startling and may give scientists at least part of the bigger picture.
One of the studies was conducted by French researchers and it looked into the impacts of chemicals on the brain of honey bees to see how it affected their ability to find their way home. What the research found was that neonicotinoids made it harder for the bees to find their way home over long distances in unfamiliar areas. The research was conducted by feeding special radio-tagged bees sugar and water laced with a low dose of neonicotinoids and releasing them. The findings of the study suggested that a colony of bees may drop as much as two thirds as a result of the impact neonicotinoids have on a bee’s ability to find its way home.
The other study was conducted by a group of British scientists. It looked at the impact neonicotinoids had on the ability of bumblebees to produce honey for their hives. The study suggests that the chemicals reduce the amount of food that the bees are able to make and thus they are incapable of making enough food for the hive to produce new queens. In a bumblebee hive, all the bees die off at the end of the winter except a few of the newly produced queen bees who go on to form hives of their own. The study found that the neonicotinoids reduced the number of queens a hive produced by about 85%.
While the studies don’t prove conclusively that neonicotinoids are the only factor contributing to CCD, it does indicate that they may be a major contributor. One new study which has yet to be published indicates that neonicotinoids may make bees more susceptible to viruses and fungi. While there is no definite evidence that neonicotinoids are the cause of CCD, there is a growing amount that indicates that neonicotinoids are very bad for bees.