Back in 2007, Wired Magazine mused:
It’s only slightly less ridiculous than the other bee killing theory that year – cell phones.
I published a story about the loony idea that was proposed by some researcher in Europe about “cell phone radiation may be killing bees”. I pointed out that it was garbage then, as it is now. I thought it was so ridiculous that I made some spoof artwork on it:
Fast forward to 2012, it looks like the culprit for colony collapse disorder has been found and it has nothing to do with global warming. The best part? Some scientific serendipity.
A heap of dead bees was supposed to become food for a newly captured praying mantis. Instead, the pile ended up revealing a previously unrecognized suspect in colony collapse disorder—a mysterious condition that for several years has been causing declines in U.S. honeybee populations, which are needed to pollinate many important crops. This new potential culprit is a bizarre—and potentially devastating—parasitic fly that has been taking over the bodies of honeybees (Apis mellifera) in Northern California.
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. A detailed description of the newly documented relationship was published online Tuesday in PLoS ONE.
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.
Here’s the paper, it is fully open and free for viewing:
1 Department of Biology, San Francisco State University, San Francisco, California, United States of America, 2 Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California, United States of America, 3 Entomology Section, Natural History Museum of Los Angeles County, Los Angeles, California, United States of America
Honey bee colonies are subject to numerous pathogens and parasites. Interaction among multiple pathogens and parasites is the proposed cause for Colony Collapse Disorder (CCD), a syndrome characterized by worker bees abandoning their hive. Here we provide the first documentation that the phorid fly Apocephalus borealis, previously known to parasitize bumble bees, also infects and eventually kills honey bees and may pose an emerging threat to North American apiculture. Parasitized honey bees show hive abandonment behavior, leaving their hives at night and dying shortly thereafter. On average, seven days later up to 13 phorid larvae emerge from each dead bee and pupate away from the bee. Using DNA barcoding, we confirmed that phorids that emerged from honey bees and bumble bees were the same species. Microarray analyses of honey bees from infected hives revealed that these bees are often infected with deformed wing virus and Nosema ceranae. Larvae and adult phorids also tested positive for these pathogens, implicating the fly as a potential vector or reservoir of these honey bee pathogens. Phorid parasitism may affect hive viability since 77% of sites sampled in the San Francisco Bay Area were infected by the fly and microarray analyses detected phorids in commercial hives in South Dakota and California’s Central Valley. Understanding details of phorid infection may shed light on similar hive abandonment behaviors seen in CCD.
Here’s the culprit exiting a dead bee, figure 2C from the paper:
It appears the commercialization of honeybees, and the tendency to truck them around the nation for pollinization contributed to the spread of the parasite. The researchers mapped the process:
This episode reminds me of the wailing over toads being killed due to “global warming” only to discover later it was a parasite…or how about Penguins? Remember that one? Nutty Story of the Day: “Global Warming” is Killing the Penguins in Antarctica. Turns out there was no connection at all. The next time we see some journalist going off on global warming causing something to die, please remind them of these blatant failures in correlation is not causation.