A World Without Bees: Declining Colonies Could Threaten the World’s Food Crops
There are two classes of endangered animals in the world. (Three if you count honest politicians.) The first is the cute and fluffy or clever ones with limpid eyes who show up on World Wildlife Fund calendars, Discovery Channel documentaries and environmental greeting cards. As they have very good public relations machines behind them, they get the lion’s share of attention. The second class is just as endangered but far less likely to show up as plush children’s toys whose sales raise 10 percent for conservation: think insects, crustaceans, burrowing rodents and other creatures that make many people’s skin crawl.
While not yet completely endangered, there is one creature whose threatened existence could have a significant impact on life on Earth, though he doesn’t get much press: the humble honeybee. While it doesn’t exactly top the news, honeybees all over the world are dying in record numbers, and nobody knows precisely why.
The first reports of disappearing honeybees came in late 2006 when a Pennsylvania beekeeper overwintering in Florida began reporting inexplicable losses in his honeybee colonies. In early February, several large commercial migratory beekeepers in other eastern states began reporting large losses of bee colonies: in some cases, as high as 90 percent of bees with the remaining bees either juvenile or so weakened they were unable to pollinate or make honey. Later that year, beekeepers in Florida, Midwestern and Pacific states began reporting losses as well. By the next year, five Canadian provinces and several European nations began noticing heavy losses of honeybees, followed by South and Central America and many Asian nations. By 2010, the U.S. Department of Agricultural (USDA) estimated that during each year since the phenomena began, more than one-third of U.S. honeybees had been lost – in other words, 34 percent each year from 2007 to 2010.
While it’s hard to imagine that the disappearance of a bug could threaten human welfare, consider who pollinates plants, including food crops. While the wind is an important factor, so are the bees. It’s estimated that bee pollination is responsible for about $15 billion in crops each year. In fact, about 130 different food crops – particularly crops such as almonds and other nuts, berries, fruits and vegetables – owe their existence to honeybees. The USDA estimates that about one mouthful out of every three that we eat is owed (either directly or indirectly) to honeybee pollination. Globally, it’s estimated that 9.5 percent of the total economic value of agricultural products for human consumption comes from insect pollination – in 2005, this amounted to just under $200 billion. The almond crop is particular reliant on honeybees: it’s one of the first crops of the growing season that needs bee pollination. California’s almond crop (which represents 75 percent of the world’s almonds) uses 1.3 million colonies of bees, approximately one half of all honey bees in the U.S., and this need is projected to grow to 1.5 million colonies by 2010.
So where are they bees going? According to experts, they’re dying, thanks to something called colony collapse disorder (CCD). And while bee biologists say honeybee colony health has been declining since the 1980s due to a combination of factors, CCD is responsible for the sudden collapse since 2007.
So what’s causing CCD? Nobody’s really sure. Scientists have examined a number of factors, including apiary management practices and environmental factors such as pesticides. While they’ve found a few common factors shared by most bee colonies experiencing CCD, no single, overriding common environmental agent jumps out as solely responsible. In particular, researchers are looking into pesticides – particularly a new class of them called neonicotinoids, which are derived from nicotine – which may be having unexpected negative effects on honey bees. Bees, apparently, have a unique response when exposed to many harmful chemicals: their systems activate a set of “detoxifying genes” in the presence of some pesticides, which could also be responsible for a chain reaction that causes weakened health and, subsequently, CCD.
While some in the bee industry remain passionately convinced that neonicotinoid are to blame, researchers caution that the data may not be all there. France banned a neonicotinoid called imidacloprid in 2005, after research indicated it could be harmful to bees. Other studies failed to replicate the results of the French study, and since that nation has banned neonicotinoid, there has been no widespread recovery in honeybee populations in France.
Still, an environmental group called Beyond Pesticides is calling on the U.S. Environmental Protection Agency (EPA) to take strong action against the neonicotinoid pesticide Clothianidin in the U.S. The action is currently in an open comments period, and a number of groups have joined in the drive to block use of the chemical, citing extensive science (they say) that shows the pesticide’s toxic effects on honeybees.
Beyond Pesticides is also alleging that Clothianidin is being sold illegally in the U.S. The pesticide was initially registered with the EPA by German pharmaceutical company Bayer in 2003. There was a condition, however: Bayer was required to complete and submit a field study demonstrating the chemical’s effects on pollinators such as honeybees. Beyond Pesticides claims that the pollinator study subsequently submitted by Bayer was deemed insufficient by the EPA to fulfill the field study requirement. As a result, says the environmental group, Bayer did not meet the terms of registration, and is therefore selling Clothianidin illegally. The EPA, however, took no action against Clothianidin and its maker, and the environmental group is pushing for the EPA to pull Clothianidin’s registration.
Another cause for CCD that has been put forth involves a new parasite or pathogen that may be attacking and weakening honey bees, particularly a pathogenic gut microbe called Nosema. Viruses have also been accused of being the culprits, and research has been carried out to that end. A mite called varroa (which feeds on bee blood and transmits bee viruses) has also been blamed. (More on that later.)
Many scientists doubt there is one overriding cause of CCD, but believe it to be a combination of factors…a sort of “a perfect storm” of existing environmental causes and stresses that have weakened honeybee colonies to the point of collapse. Stress, just as in humans, can compromise the immune system of honeybees and disrupt their whole bee social system, making them more susceptible to disease.
So what stresses out a honey bee? Poor nutrition due to apiary overcrowding, for starters, and overwork. Pollination of crops with low nutritional value and pollen with scarce nectar have also been cited as causes. Inadequate water supplies and something called “migratory stress” have been cited. Another factor may be traveling. (As everyone knows, traveling can be stressful.) Bees are considered portable, and some farmers, rather than keeping bees of their own, call for hives to supply pollination services each spring. The bees are shipped and trucked in hives from place to place as needed, something scientists think could be contributing to stress. Each growing season, beekeepers travel through agricultural areas with hives on their flatbed trucks, stopping for a few weeks at a time to pollinate various crops including almonds, cantaloupe, apples and blueberries.
One of the CCD causes that has been garnering the most attention as of late involves a virus transmitted by the varroa mite. Called
Israeli acute paralysis virus (IAPV), it has been found in almost all samples from honeybee colonies with CCD (about 96.1 percent of them), but not in unaffected colonies. However, many researchers warn that it’s still too early to draw a conclusion that IAPV is the sole reason for the honeybees’ distress.
Scientists recently thought they had found a break in their investigation when they discovered a prevalence of IAPV in bees imported from Australia and in royal jelly samples imported from China. Researchers jumped all over imports of Australian honey bees (which first began in 2005, leading to a tempting conclusion that the imports were to blame). Upon further examination, including genetic screening of dead bees collected between 2002 and 2007 in several U.S. states and Israel, researchers found that IAPV has been present in U.S. bee colonies since before the Australian imports began.
At this time, most researchers still embrace the “combination of factors” theory as to the cause of CCD.
“What I believe is that CCD is likely a combination of factors, as opposed to a single, discrete cause,” says entomologist Jeff Pettis, head of research at the USDA’s Agricultural Research Service (ARS) Bee Research Laboratory in Beltsville, Md. “I wish the answer was as simple as the question.”
As it turns out, colony collapse disorder isn’t completely new. There are a number of documented honeybee “disappearances” that occurred in the U.S. in the 1880s, the 1920s and again in the 1960s. While scientists examining the records of those incidences say they closely resemble the CCD they are seeing today, there is apparently no way to be certain if the historical occurrences were caused by some of the same factors suspected today. During previous instances of bee colony collapse, weather was often blamed. A collapse of bee colonies that occurred in Utah in 1903 was blamed on the weather, specifically a “hard winter and a cold spring.” Weather was also suspected in a collapse that decimated more than half the honeybee colonies in Pennsylvania in the mid-90s.
So what happens next? As for right now, scientists say that the situation isn’t as dire as we might think. While overall, the die-off has been causing roughly 30 percent of captive honeybees to die at the end of each winter, beekeepers have been able to take steps to rejuvenate their hives each year so that by summer the population is back to previous levels.
Despite the reduction in bees, better crop yields have kept food prices from rising substantially, says the USDA. Prices for nearly a dozen fruits and vegetables that require bees to pollinate them haven’t risen markedly over the last six years, says the agency. Even the almond industry, hardest hit by the reduction in populations of honeybees, has managed to keep prices largely steady so far.
So what’s to be done about the problem? Further research, say scientists. Investigation into the recently sequenced honeybee genome is expected to help provide a better understanding of bees’ biology, and might be used to help “breed better bees” and determine what causes them to become unhealthy. The data might be used for better bee management that will reduce stress on the bees and help prevent infection from pathogens or viruses. In addition, bee biologists say they will continue looking into the four factors being blamed for CCD: pathogens, parasites, environmental stresses and bee management techniques.
In the meantime, bee biologists note that the best way for beekeepers to prevent decimation by CCD is to take steps to keep their honeybees as healthy as possible. Many beekeepers are rejuvenating their bees at the beginning of new growing seasons by buying a new queen or two, then splitting the hives to regenerate, according to a recent CNNMoney report. Beekeepers are also supplementing the bees’ natural diet of pollen and nectar with other proteins in an attempt to keep them healthier.
A West Palm Beach, Florida-based company called BeesFree recently announced it is seeking a patent for what the company calls “the first known, commercially viable cure” for CCD. The company’s solution integrates a new kind of dispenser (or a “beespenser” designed specifically to appeal to bees with the types of colors and shapes the little guys prefer) with a proprietary water-soluble nutritional compound that consists of a mix of antimicrobial agents and compounds, nutrients and antioxidants.
But while honeybees are getting the most attention, scientists say they’re not the only ones affected. Since the 2006 epidemic of CCD began, several species of bumblebees – also heavily responsible for plant pollination – have gone extinct, which leaves researchers concerned about the wider environmental picture behind the bees’ disappearance. Many wonder whether the devastation of the bees is an early warning sign of a bigger agricultural crisis that could ultimately challenge the world’s food supply.
For now, significant mysteries remain. For starters, the deaths are also thought to be occurring in wild honeybees as well as captive ones. Another great mystery is the truly “disappearing bees.” Scientists say that as many as 10 percent of captive honeybees are simply vanishing, disappearing without leaving any bee corpses behind, something that sounds more than a little Stephen King-ish. In the meantime, as a consumer, there isn’t much you can do except to wish the little guys well.
And you may want to wean yourself off that honey-roasted almond habit, just in case.