Honey bees are slowly but steadily becoming an endangered species. Bee hives are suffering from what is known as Colony Collapse Disorder (CCD), which causes bees ro permanently leave their hives and then die. The trend is disturbing, especially since bees are necessary for pollinating more than 30% of the world’s crops. They also produce honey, which is a tasty product we hope never goes away. We’ve done everything we can to find out why this is happening, and various studies have blamed the problem on everything from cellphones to high fructose corn syrup. A new study, though, proves that at least one of the culprits is almost definitely a particular class of insecticides, called neonicotinoids.
The study, done by the Harvard School of Public Health, began with a total of 18 bee colonies. These colonies, which were divided into three groups, were studied over the course of seven months last year. The researchers treated two of the groups with neonicotinoids: imidacloprid and clothianidin. The third group was left untreated. Although there was a decline in all three groups during winter, which is typical, the untreated group flourished in spring (except for one colony that fell to a common parasite). But six of the 12 of the treated hives completely collapsed.
This 50% mortality rate for bees exposed to neonicotinoids is hard to ignore. However, a previous study showed that pesticide-treated hives had even worse luck surviving: the mortality rate during that study was a staggering 94%.
Understanding all factors of CCD is important, especially if we want to prevent bee loss and increase the bee population. Lead author of the study, Chensheng Lu said:
“Although we have demonstrated the validity of the association between neonicotinoids and CCD in this study, future research could help elucidate the biological mechanism that is responsible for linking sub-lethal neonicotinoid exposures to CCD. Hopefully, we can reverse the continuing trend of honey bee loss.”