For the past few years, a seemingly common but vital insect has been unexpectedly disappearing: the honeybee. This rare phenomenon is known as Colony Collapse Disorder (CCD), and it has been observed by beekeepers since 2006. The specific cause of this phenomenon has not been fully determined.
According to the U.S. Department of Agriculture (USDA)’s website, “Bee pollination is responsible for $15 billion in added crop value, particularly for specialty crops such as almonds and other nuts, berries, fruits, and vegetables.”
“It is commonly agreed that about one-third of the human diet is dependant on honeybees for its economic production,” said Robert Sears, president of the Eastern Missouri Beekeepers Association. “This means almost everything that has very much color or texture-fruit, vegetables, nuts. Without honeybees, the human diet would be very limited to starches-wheat, rice, etc. Even meat to a large extent would be affected because the seed crops that cattle feed on are pollinated by honeybees.”
This is not the first time that farmers and beekeepers have seen a sudden, unexplainable decline of honeybees. The USDA reports that the honeybee population declined noticeably in the 1880’s 1920’s, and 1960’s.
The rate of bee disappearance is especially prominent in the U.S., but it is a worldwide problem as well.
“They’re disappearing by droves already; about 30% of the honeybee colonies in the United States,” Sears said. “It’s international, it’s occurring in Europe and in China.”
According to the USDA, one of the striking differences between colonies that have experienced CCD compared to colonies without CCD is that some colonies with CCD have been infected with the Israeli acute paralysis virus (IAPV), yet none of those without the disorder have the virus.
Sears believes the disorder might be linked to bees’ weakened immune systems, pesticide use, and stress. Due to the importance of bees to several aspects of the agriculture industry, the bees are under frequent physical stress as they pollinate several different crops.
“The RNA of the colonies which show this syndrome is compromised and therefore, the colonies and the bees are what are called immune suppressed, which means they are more susceptible to diseases,” Sears said.
Researchers at the University of Illinois Department of Entomology have recently discovered a direct correlation between fragmented ribosomal RNA and CCD. Ribosomal RNA is the genetic mechanism that functions as a set of ‘instructions’ that codes for the manufacturing proteins. Without cohesive RNA, many essential proteins cannot be properly produced. Some fragmenting of RNA is common to many organisms. According to researchers at the University of Illinois, in colonies that have been affected by CCD, several bees have unusually high rates of fragmented RNA.
The high prevalence of fragmented RNA was consistent in all colonies infected with CCD, regardless of differences in other variables. Viruses like IAPV are responsible for using the ribosome, the protein-manufacturing center of cells, to make their own proteins. The use of ribosomes by viruses might contribute to the fragmenting of ordinary RNA.
However, beekeepers could minimize their colonies’ risk of developing CCD.
“Beekeepers could improve their beekeeping management and reduce their dependence on chemicals,” Sears said. “I think that we have created a chemical soup in the beeswax in our hives and it’s not a healthy environment, we see higher loads of pathogens-and we think those might be contributing to CCD.”
The variations between colonies with CCD make pinpointing the cause of the condition more elusive.
“A lot of the colonies that are affected by CCD don’t share a single variable,” Sears said. “The colonies that have CCD are more likely to have a higher pathogen load than colonies that don’t.”
Beekeeper organizations are currently working to raise public awareness of the issue and are changing their beekeeping techniques based on emerging findings about the rate of colony loss.
“I think the public is much more informed now than they were one or two years ago,” Sears said. “From 2008 to today, we’ve increased the number of honeybee colonies by about 300. A lot of them swarm [the way the colonies reproduce themselves naturally] and there are additional colonies that we call ‘pheral,’ that will set up a colony in a tree or an attic. The more bees we have, the more genetic diversity there’s going to be. By increasing the number of beekeepers, we hope to contribute to the long-term interest of honeybees.”