Why Are Honeybees Dying Off? According to Mr. Green, it's complicatedWe’re pretty certain that bees are not dying from GMOs, cellphones, ultraviolet lights, electromagnetic radiation, or aliens, all of which have been blamed at one point or another. There is no single cause, according to most scientists who have studied the problem, but rather a combination of factors that include parasites, pathogens, pesticides, poor nutrition, and habitat loss.