Colony collapse disorder, the “phenomenon in which worker bees from a beehive or European honey bee colony abruptly disappear,” has been attributed to everything from cell phone radiation to fungi, but scientists have not been able to find a consistent link among affected colonies. A recent discovery of the larvae of a parasitic fly inside of some dead honeybees may provide that link. Researchers have found that the parasitized bees tend to behave strangely, acting almost like zombies. Eventually, the affected bees leave the hives at night, fly into a light source, and lose control of their bodies before falling to the ground and being partially decapitated by the larvae emerging from the bee’s neck. Gross.
John Hafernik, a biology professor at San Francisco State University, had collected some belly-up bees from the ground underneath lights around the University’s biology building. “But being an absent-minded professor,” he noted in a prepared statement, “I left them in a vial on my desk and forgot about them.” He soon got a shock. “The next time I looked at the vial, there were all these fly pupae surrounding the bees,” he said. A fly (Apocephalus borealis) had inserted its eggs into the bees, using their bodies as a home for its developing larvae. And the invaders had somehow led the bees from their hives to their deaths….
The team found evidence of the fly in 77 percent of the hives they sampled in the Bay Area of California, as well as in some hives in the state’s agricultural Central Valley and in South Dakota. Previous research has found evidence that mites, a virus, a fungus, or a combination of these factors might be responsible for the widespread colony collapse….
Bees from affected hives—and the parasitizing flies and their larvae—curiously also contained genetic traces of Nosema ceranae, another parasite, as well as a virus that leads to deformed wings—which had already been implicated in colony collapse disorder. This double infection suggests that the flies might even be spreading these additional hive-weakening factors.
So maybe it’s not a sign of the end of the world after all. Not that you ever thought that…right?