For over a decade, a disease called colony collapse disorder has been destroying bee populations worldwide. Because bees pollinate many of our staple crops, their deaths threaten our food supplies. Now, new evidence is solidifying a case against the likely culprit in their deaths.
Photo by Alex Wild
Researchers have previously argued that colony collapse is being caused by neonicotinoids, a form of insecticide that works by damaging the insects' brain functions and shutting down their nervous systems. After a period of excitability, insects exposed to neonicotinoids are paralyzed and subsequently die.
Now, in a new paper published by Harvard environmental biologist Chensheng Lu and colleagues in Bulletin of Insectology, we have confirmation that hives exposed to neonicotinoids are far more likely to suffer colony collapse than those that aren't. Symptoms of colony collapse disorder (CCD) include wildly unpredictable bee behavior, with bees fleeing their hives in winter and never returning. This seems to fit with exposure to a pesticide that works by interfering with the activity of neurotransmitters in their brains.