By Erin Volheim
Honeybees are the only known animals besides humans to have a representational language; one that in order to be decoded, engages the imagination of the receiver.
The mystery affecting honeybees worldwide, known as Colony Collapse Disorder (CCD), also requires the observer to decipher meaning in several ways. Information is being conveyed by these events, telling humans to “just do something,” but what that “something” actually is seems left up to the imagination of the person receiving the message.
Native Americans once referred to imported European honeybees as “white men’s flies.” Apis mellifera, commonly known as the western honeybee, is a non-native species accounting for nearly all the bees maintained by beekeepers in North America. It’s a floral generalist that will feed on just about anything that is blooming. Bees are descended from predatory wasps, and they evolved from eating other insects to feeding on flowers some hundred million years ago, shortly after flowers first appeared on the landscape. In the world of the hive, it’s not abnormal for a 1,000 bees to die in one day, or for them to choose voluntary exile when the hive is compromised, like being over-run by small hive beetles. It’s also not unusual to lose a whole hive during the winter, when the bees cluster together with whatever stores of honey they can gather to try to stay warm and healthy. The queen bee lays some eggs in December and kicks into high egg-producing gear in January. Still, she may fail to produce enough larvae to replace short-lived adults. The hive may also starve, if food storage supply is inadequate, or collapse if there is too small a population to maintain a high enough hive temperature.
In order to survive as a bee colony of sometimes 100,000 individuals, the communal structure has to be adaptable to seasonal changes and the availability of food. While the division of labor in a bee colony is quite complex, it can be roughly be seen as those who work inside the hive and those who work outside.
In the mystery of CCD, the ones disappearing are worker bees, mostly sterile females. They secrete the wax used to build the hive, perform hive cleaning and maintenance, raise the young, guard it and forage for nectar and pollen.
Something similar to CCD was first seen in France in 1994. French beekeepers named the phenomena “Mad Bee Disease,’ as only insane bees would leave the baby brood. In this case, worker bees seemed to be visibly disoriented and would stay away from their hives, leading them to die of exposure to the cold. What distinguishes CCD from Mad Bee Disease is a rapid destruction of a colony that appears to be thriving weeks or days before.
Noticed in the fall of 2006 and named in the spring of 2007, CCD is simply when a beekeeper finds a low number of adult honey bees (sometimes zero) present in the hive, yet like Mad Bee Disease, the queen and her brood are present. Curiously, there are no bee carcasses in or around the area and there is also honey still in the hive. Neighboring hives also do not seem interested in raiding this free food, which in other hive collapses is a commonplace occurrence.
The “cause” of CCD is currently under investigation. To be sure, the panic has outpaced the science, probably because it goes right to our stomachs. One out of every three bites of food that you consume has been a result of a honeybee pollinating that particular crop. Certainly, CCD will soon have a dramatic effect on our domestic food supply, mainly in how much food costs in a time where fuel prices are already having an impact.
There were enough honeybees to provide all the pollination needed in 2007. Specific reports of CCD during the last year were not much greater than they were in 2006. A survey of managed hives done in late 2007 by the Bee Research Lab and the Apiary Inspectors of America showed that beekeepers lost about 35 percent of their hives compared to 31 percent in 2006.
Beekeepers and investigators have suggested varroa mites, drought, proximity to power lines and cell phone towers, colony treatment styles, moving stresses, genetically modified crops, lack of genetic diversity in the queens, inadequate nutrition, monoculture crops, pesticides and other chemicals present in the bee’s environment. A number of people have blamed genetically modified (GM) crops for the widespread bee deaths. Many GM seeds are dipped first in systemic insecticides that later appear in the plants’ nectar and pollen. This makes GM plants suspect because of their chemical treatment history.
CCD has become a catch-all phrase for hive problems. A significant part of the analysis hinges upon distinguishing between true CCD losses and non-CCD losses.
Scientists like entomologist Jeff Pettis, research leader for the Agricultural Research Services’ Bee Research Laboratory believe “CCD is likely a combination of factors, as opposed to a single, discrete cause.”
Nosema apis, is a microsporidian fungus that lives in the digestive tract of honeybees, and has been present in the U.S. for many years. In 2006, scientists discovered and identified a new nosema species, Nosema ceranae, present in some colonies displaying symptoms of CCD. This fungus had also been seen before, sometimes in colonies that were healthy. Tests of genetic material taken from a collapsed colony in Merced County, California point to this once rare N. ceranae that previously affected only Asian honeybees, but has evolved into a strain lethal to European honeybees dominantly used in the U.S.They found honeybees can die within eight days after exposure to N. ceranae, faster than bees exposed to N. apis.
The foraging workforce seems to be affected the most. They leave the colony and are too weak to return, thus dying in the field. This leaves behind a small cluster and a weak colony, very similar to the symptoms of CCD. Although many do not consider N. ceranae to be the sole cause of CCD, it and other new pathogens may play an important role in elevated bee deaths.
Despite CCD, the varroa mite still remains the world’s most prolific honeybee killer. Varroa has been in the U.S. since 1987. The mite has very sharp mouthparts, which it uses to pierce the bee’s exoskeleton. The varroa spits a protein into the bee, breaking down the victim’s immune system. Not surprisingly, varroa has been considered a possible causes of CCD, though many afflicted hives do not contain a trace of the mite. Many of the chemicals used in bee colonies are used to control varroa, eliciting an all-out chemical assault from conventional beekeepers.
Migratory beekeeper David Hackenberg from Pennsylvania, was the first to call in about his abnormal hive losses in 2006. The call was received by the state’s apiary inspector, Dennis van Engelsdorp, who initially figured the problem had to do with mites or diseases. Slicing up Hackenberg’s bees convinced him that there was something else happening.
Under a microscope, bee innards appear white. Hackenberg’s bees were filled with black scar tissue. After more beekeepers began reporting problems, van Engelsdorp started traveling around the country collecting samples. Molecular tests confirmed his initial impression. The bees were infected with just about every bee virus known, including deformed-wing virus, sac-brood virus, black-queen-cell virus, various fungi and bacteria. Genetic analysis revealed the presence of new pathogens, never before sequenced. Due to the level of infection, van Engelsdorp and other researchers concluded that the bees’ immune systems had collapsed.
In theory, any combination of stresses (chemicals, genetic bottlenecks, varroa, etc.) can suppress a bee’s immune system. Considering synergistic effects as a potential cause of CCD makes the disorder increasingly harder to study.
The honeybee genome was recently mapped, revealing that honeybees may be peculiarly vulnerable to disease and toxins. Scientists found that bees did not have the normal complement of genes that tackle poisons, or many immune-disease-fighting genes. In comparison, a fruitfly or a mosquito have twice the number of toxin-fighting genes. Fortunately, male mosquitoes are also important pollinators, despite the female’s bloodsucking behavior.
Smaller honeybee operations on organic farms in general are not experiencing CCD. Organic certification requires that hives not be placed within foraging range – about six miles – of conventional farms. There are around 1,200 small-scale beekeepers that don’t use any chemicals (including the more natural formic acid to control mites) in their hives. This style of “biological beekeeping,” attempts to keep hives closer to the way that bees would live in the wild. It’s called “small-cell beekeeping.” Many believe that breeding for size is a factor in CCD. They have seen that commercial honeybees are now too large to feed on some of the very plants that historically may have given them immunity to diseases and parasites.
Scientists are investigating the lack of genetic diversity and lineage of bees, both related to queen quality, as possible causes of CCD. Fewer than 500 breeder queens produce the millions of queen bees (and therefore all bees) used throughout the U.S. Geneticists refer to this as a genetic bottle neck. This lack of genetic diversity has, in effect, made U.S. honey bees a virtual monoculture, which are generally more susceptible to any pest or disease invading the system.
The migratory beekeeping industry is overly dependent on pesticides and antibiotics used to treat various bee-related maladies. Misuse of chemicals is rampant. In many cases, the pesticides used to control varroa mite double as insecticides in other pest management schemes. Putting insecticides into insect colonies cannot be beneficial to bees, even if the chemicals are not killing the bees outright. In addition to being exposed to chemicals while pollinating industrial crops, honeybees also may become toxificated when drinking from contaminated water sources. These chemical residues then accumulate in wax and food stores in the colony, thus killing bees.
In 1991, Bayer’s imidacloprid, a neonicotinoid, was registered here in the U.S. These type of pesticides are designed to leave bees unharmed, but can deliver a sub-lethal dose of the toxin. They interfere with the bee’s ability to learn where pollen is, and negatively impact their immune systems.
Imidacloprid, sold under the name of Gaucho, has been banned in France for use on corn and sunflower crops, but is now sold here under a name Admire. In the U.S., there has not been direct proof of neonicotinoids killing bees as has been found in Europe. On May 15, 2008 Germany banned another neonicotinoid, clothiandin, for all uses as it was proven especially lethal to honey bees.
Now a 100 years later, these toxified migratory hives are a crucial element of a highly dependent U.S. monocrop agriculture.
Beekeepers earn much more from renting their bees out for pollination than from honey production. Cheap corn syrup and white sugar have drawn the honey market down. Monocrop industrial agriculture could not replace current levels of productivity with native pollinators alone, even if these populations weren’t on the decline as well.
Diet and stress come into play when the bees are transported by commercial beekeepers to pollinate large fields of crops. Bees shipped into an area to pollinate a single food crop will take that pollen back to the hive as food for their larva. A diet that is not diverse does not promote the growth of a healthy immune system. Honeybees are ill-suited to withstand the kind of stresses they encounter when they travel from crop to crop, intermingling with bees from other places and the viral, bacterial and parasitic hitchhikers they bring with them. Bees from all over the U.S. are put in close proximity in California’s almond orchards in the spring. Conventional almond grower’s use around 42 different herbicides, fungicides and pesticides during their growth cycle.
Almonds have an extremely high pollination requirement—nearly all the flowers in an orchard must be cross-pollinated to produce a commercial crop. The price of renting a hive during the almond bloom, which starts in late February, rose from $55 four years ago to $150 this year, and next year will likely reach $175.
It is estimated that to service California’s $2 billion worth of almonds will require nearly 1.5 million hives, roughly two-thirds of all the colonies that existed in this country before CCD. As more acreage goes into production, it is expected that almonds will require 2.1 million colonies in the next five years, nearly all the hives that are currently being kept. Only 10 percent of the almond crop is used domestically the rest is transported to 80 countries throughout the world.
In the U.S., about 30 percent of commercial crops utilize honeybees for their pollination. Even among those, some of the bee usage is superfluous, as native pollinators are actually doing the work. Many native plants on the endangered species list lost their native pollinators due to displacement by feralized honey bees. Poignantly, non-native honeybees became the great pollinators of U.S. agriculture when populations of native pollinating insects were killed by the heavy pesticide use of the last 50 years of chemical agriculture. Even today, pesticide misuse has driven beekeepers out of business, but can affect native wild bees even more, because they have no human to move or protect them. Scientists now say the decline in managed hives of European honeybees makes the role of wild native bees as pollinators even more important.
The U.S. Senate and 30 state governors declared June 22-28, 2008 National Pollinator Week. After testimony by big time migratory beekeepers and commercial growers in front of Congress, Agriculture Secretary Ed Schafer announced on July 17, that more than $4 million will be awarded to the University of Georgia to study the causes of CCD and other diseases affecting bee populations. Honeybee pollination is valued at $15 billion annually to U.S. agriculture.
The steady increase in beekeeper migration has masked the issue of native pollinator decline from public awareness which groups like the Xerces Society are trying to redirect. Instead of sinking more resources into band-aiding a defective system, maybe the message we are receiving from the honeybees is that monocrop export agriculture dependent on migratory beekeeping is just not sustainable. Yet, sudden blocks to migratory beekeeping would have catastrophic results on the global food supply.
In the meantime, perhaps we should downsize the scale of our agricultural practices, put our energy toward more small-scale farms and community gardens. Direct funding toward increasing biodiversity on our farms and other efforts to encourage our native pollinators. Increase support to programs, locally and globally, that give folks the skills to grow food for their communities, while repealing trade agreements that make importing food cheaper than growing it nearby.
CCD represents an opportunity to listen and take action. A time to respect and restore our connection to native pollinators, rather than buying into the short-term sustenance of the commercial growers’ bank account.
Erin Volheim writes from the Little Applegate Valley of Southern Oregon.