Scientists in the United States have discovered that a fly parasite can turn honey bees into confused zombies before killing them, a discovery that might offer new clues as to why bee colonies are collapsing in disturbing numbers all around the world.
As of now, the fly parasite has only been detected in honey bees in areas of California and South Dakota, researchers reported in the science journal PLoS ONE this past week. However, if it turns out to be an emerging parasite, this "underlines the danger that could threaten honey bee colonies throughout North America," says the study published by San Francisco State University professor of biology John Hafernik.
The parasite nests in the stomach of the bees and causes them to walk in circles, sometimes pursuing bright lights, before eventually dying. Bees usually just sit in one place, sometimes curling up before they die. But the infected bees were still alive, unable to stand up on their own legs. “They kept stretching them out and then falling over,” reports Andrew Core, a graduate student in Hafernik's lab. “It really painted a picture of something like a zombie.” Once bees were infected by the fly parasite, they would then abandon their hives and congregate near lights, a highly unusual behavior for bees.
Scientists and bee experts have theorized that the huge die-off of bees worldwide that first came to light in 2006, a major threat to crops that depend on the honey-making insects for pollination, cannot be attributed to any one factor. Parasites, viral and bacterial infections, pesticides, as well as poor nutrition resulting from the impact of human activities on the environment have all played a role in the troubling decline. The mysterious decimation of honey bee populations in the United States, Europe, Japan and elsewhere in the past decade threatens agricultural production worth tens of billions of dollars and the very future of the food chain for humanity.