A new study has been published that suggests that honeybees are exhibiting zombie-like behavior after unknowingly hosting a parasitic fly.
San Francisco State University researchers have conducted a study that suggests honey bees can become disoriented after hosting the parasite.
According to a Jan. 3 press release, this observation may help scientists uncover more about colony collapse disorder (CCD). Since 2006 experts have been mystified by the ailment that has led to a significant increase in honey bee colony losses, a concern since honey bees are a vital part of the process in pollinating crops.
The statement outlines how the discovery occurred. SF State Professor of Biology John Hafernik said he didn't set out to study the parasitized bees, but rather was looking for insects to feed a praying mantis he brought back to the university after a entomology field trip. He collected some bees that had been underneath some light fixtures.
"But being an absent-minded professor," Hafernik joked, "I left them in a vial on my desk and forgot about them. Then the next time I looked at the vial, there were all these fly pupae surrounding the bees."
What scientists noted was the fly, Apocephalus borealis, lays its eggs in the bees' abdomens making a "home". About a week after the bee dies, scientists said, "fly larvae push their way into the world from between the bee's head and thorax. But it's the middle part of this macabre story that may be the most scientifically interesting to those studying the dramatic and mysterious disappearance of honey bees."
These flies had been determined earlier to parasitize bumble bees, said the report's abstract.
Experts said the bees then abandoned their hives "in what is literally a flight of the living dead" as they head towards lights.
"When we observed the bees for some time—the ones that were alive—we found that they walked around in circles, often with no sense of direction," said Andrew Core, a SF State graduate student from Hafernik's lab who is the lead author on the study.
"They kept stretching them out and then falling over," Core said. "It really painted a picture of something like a zombie."
Reportedly, nighttime bees who forage are believed to be more susceptible to falling victim to the flies than bees that feed during the day, although scientists can't be sure. They said flies are not frequenting hives, so the theory is the flies are attaching to the bees when they are away from the hive.
Additionally researchers found evidence of the presence of Nosema ceranae, another parasite, and a virus that causes deformed wings, said the blog, Scientific American.
This study is considered to be significant because it can help experts perhaps determine why so many honeybee colonies are disappearing. Currently the phenomenon has only been pinpointed in California and South Dakota, but scientists will now be looking more closely to see if it is a contributor to CCD.
Researchers plan to track the bees with radio tags and video cameras to see where they are attacked by the parasite flies.
In spring 2011 scientists had discovered an incidence of 'zombie ants' located in the Thailand rain forests.
Plos One, a peer-reviewed science site, published the 'zombie' honey bee study on Jan. 3.