BUZZ FREE: A WORLD WITHOUT BEES
stuck under a truck in the atacama desert, chile
It was three in the afternoon and over 30 degrees C, yet despite the heat there was not a drop of sweat on my body. The air was so dry that any perspiration was sucked from my pores before I even felt it. I could see for miles in all directions, but there was no sign of human habitation. I hadn't seen a soul for hours. The entire vista was in two colours—the ground was beige and the sky blue—and even the Andes Mountains, faintly visible on the horizon, looked blue from this distance. I had been stuck here in the Atacama Desert in northern Chile for three hours, trying to dig the back wheels of a half-ton truck out of the sand.
The day had begun well. I had found a tiny trickle of water emerging from an embankment at the side of a dirt road; there was some vegetation growing around the moisture, and some bees were visiting the flowers. I collected a few of them and then drove off towards my next sample site. Two hours of driving and three hours of digging later, and I had not seen a single living thing—no other drivers, not an insect, not a plant.
The Atacama Desert is both the driest and the oldest desert in the world. People claim that there are parts of this desert where rain has never fallen, although geologists have told me that it must have rained at least once in the past hundred years over most of this enormous stretch of barren land. There are indications of past precipitation on the surfaces of the mine tailings, extrusions from the nitrate mines that dotted the landscape with human activity a century ago. This is an eerie place to travel, as in some areas the only signs of past human habitation are the graveyards that house the dead. The mausoleums shelter the desiccated remains of the mine managers and their families (the miners themselves were given less prestigious burials). Apart from some vandalism, the coffins and their contents are exactly as they were in the early years of the twentieth century. Where it (almost) never rains, the dead become mummified.
Imagine living in a place where it rains perhaps once every hundred years. Not surprisingly, detailed weather data are not available for most of this large, sparsely populated area, but there are meteorological records that extend back for long periods for several places. The northernmost city in Chile is Arica; the average rainfall there between 1987 and 2002 was three millimetres per year. But that average is misleading because over one-third of the total rainfall in that sixteen-year period fell on a single day. It rained on a total of just fourteen days in those sixteen years, and in an earlier period, not a single drop of rain was recorded for fourteen years in a row. It seemed that the place where I was now stuck was drier than Arica, and I had only my broken-down truck to keep me company as the hours passed by.
This was not the first time I had got into a bit of a pickle while doing fieldwork. For my Ph.D. at the University of Toronto I had studied geographic variation in bee social behaviour, obtaining samples all the way from cold temperate Ontario to the subtropical climes of the Florida Keys. At one point I drove my car into the Okefenokee Swamp at dawn trying to get to the next sampling site in time.
Since then I have authored or co-authored over one hundred research articles on bees, most of them since becoming a professor of biology at York University in Toronto, Canada. Over the past thirty-five years I have travelled to all continents except Antarctica (where there are no bees) because of my fascination with these essential and beautiful little insects. Arid lands are my preferred destinations for the simple reason that bee diversity is higher in semi-deserts than in any other type of habitat. The normally dry and sunny weather is appealing to bees, which don't like to fly when it is raining or cloudy. Although my earliest research was mostly on bee behaviour, I have become increasingly aware of the need to promote the conservation of bees. Research performed in my laboratory demonstrates that bees are at a much higher risk of extinction than most other organisms. And that's a concern because the world as we know it would not exist without the pollination activities of bees: not only would there be few wildflowers, but our food supply would be substantially reduced. Some almost essen-tial items—such as coffee—would be at risk (though many would consider coffee absolutely essential). So it is extremely important to increase our understanding of bees and to spread the word about these valuable creatures as widely as possible.
Consequently, I now put considerable effort into increasing general awareness of the significance of bees. I have, for example, written a pamphlet on the bees of Toronto; taught bee-identification courses in Ontario, Arizona and Kenya; written identification guides to the bees of Canada and adapted previously published ones for the needs of the Food and Agriculture Organization of the United Nations.
It is because of my interest in the conservation of bees that I was in the middle of the Atacama Desert with no shade but that underneath the truck, where I had spent quite some time. Fortu- nately, I had a large drum of water—essential for anyone travelling in this part of the world—and a drum of gasoline. I knew of other entomologists who had run out of gas and been stranded in this region for days before anyone else passed by. Without water and gas, you would not last long. I imagined the headline: "Mummified Bee Biologist Found in Desert."
Large amounts of water and gas are two things everyone needs in this beautiful wilderness. But few take a drum of liquid nitro- gen with them as well. Why would I take liquid nitrogen into the desert? At -196 degrees C, it was certainly not for cooling beer. The liquid nitrogen was for storing bees in a way that prevented their proteins from breaking down. Why was I interested in the proteins of desert bees? Why was I risking life and limb studying the proteins of insects so inconspicuous that even if you had thousands of them nesting in your lawn you would probably not know it? The answers to these questions form part of an extended narrative that eventually led me to conclude that bees may be the proverbial canaries in the coal mine of the globe's terrestrial habitats. Not only do I believe that bees can tell us much about the state of the natural world, but I also believe they are particularly good at indicating the state of the environment in areas that have been considerably influenced by human activity. But in case you think bees are unim-portant, or even perhaps mostly a nuisance (after all, some of them sting), let's imagine what the world would be like without them.
Let's start with the obvious: there would be far fewer flowers. Plants have sex through the transfer of pollen from the male part of one to the female part of another. Pollen may be transported on the feathers of a hummingbird, the hairs on a fly or the tongue of a bat, and lots of it is transported by the wind (you may have an allergic response when plants are having sex using aerial currents as their intermediary). But the pollen of most flowering plant species is transported on the hairs on the body of a bee.
In the absence of bees, most flowering plants would not persist for very long. Yes, there would be some flowers left. The elongate red ones that are pollinated by hummingbirds; the large saguaro cactus flowers that are pollinated by bats; the white, moth-pollinated orchids that show up so well in the moonlight; and the dull flowers that give off a scent like rotting meat to attract pollinating flies—all of these flowering plant species could survive without bees. But the world would certainly be a less joyful place for us if the only flowers were on cactuses or smelled unpleasantly stinky.
In the complexity that is the web of life, we rarely under- stand the extent to which the continued existence of one species is dependent upon the presence of another. When it was a mere seedling, did that bat-pollinated cactus require the shade provided by a bee-pollinated flowering plant to avoid shriveling up in the dry desert heat? If so, even the cactus might disappear from the face of the planet if bees were no longer around. We simply do not know enough about ecological interdependencies to understand what proportion of the organisms on the planet rely, directly or indirectly, upon the pollination activities of bees.
Certainly the loss of all bees would result in catastrophic cascades through the terrestrial ecosystems of the world. If many of the flowering plants were to disappear, the other species that rely upon those plants would also be in trouble. How many squirrels would there be without the nuts that result from pollination by bees? How many songbirds would there be without the berries that result from pollination by bees? No squirrels and no songbirds means no predators that eat the squirrels and songbirds. So the impact of bees extends throughout the food web—even to us.
We are part of the food chain (usually the end link, because comparatively few people get eaten). We are also a very large part of the global food web, appropriating perhaps one-quarter of the entire ecological productivity of the planet. Not all our use of the world's ecological productivity is through food. We cut down rain- forests and drain peatlands to feed our insatiable demand for bio- fuels. We grow cotton for clothing, harvest wood for construction, and produce coffee to help us get going in the morning and sedatives to help us get to sleep at night. All these commodities rely to some extent upon the pollinating activities of bees.
"If the bee disappeared off the surface of the globe, man would have only four years of life left." That quotation has been attributed to Einstein, although scholars can find no evidence that the unkempt sage said anything of the sort. I think some, perhaps most, of us would survive for longer than four years without bees, but there's no question that the food supply would be substantially reduced. Why? What exactly is the impact of bees upon our food supply?
Consider breakfast. Eggs, maybe a slice of watermelon, toast with butter and jam, and a cup of coffee with a dash of milk—all are common components of a North American breakfast. The only item in the list that bees do not play a direct role in producing is your toast, since wheat is pollinated by wind.
Eggs come from chickens, and chickens eat seeds, among other things. Many of the seeds in the diet of a chicken would not be produced in the absence of pollinating activities of bees. And watermelons are entirely bee-dependent. Each fruit requires more than a thousand grains of pollen to be produced. (It's lucky for us that bees are such messy shoppers and leave behind so much of the food they collect!)
Coffee bushes do not need a pollinator to produce beans because they can self-pollinate. But when a bee moves pollen from one bush to another, the yield increase is enormous. Eggs, coffee and most fruits and vegetables would be a lot more expensive with- out bees because there would be much less of them.
What about the milk for your coffee and the butter for your toast? The cows that produce milk get most of their nourishment from grasses, which are wind-pollinated. But grass does not grow during the long winters at temperate latitudes, and alfalfa is one of the most important winter forage foods for cows. Alfalfa requires pollination to produce seed for next year's crop. A substantial pro- portion of our meat and dairy products would not be possible without the bees that pollinate alfalfa.
Last we turn to jam. Most jams come from berry crops, such as strawberries, raspberries and blueberries. These plants generally grow berries only after having been pollinated by bees.
Am I suggesting that we would all starve in an almost colour- less and stinky world if it weren't for bees? No, that would be an exaggeration. Many of the world's staple crops are wind-pollinated, including various cereals, rice and corn. Others crops are pollinated by insects that are not bees; chocolate, for instance, is produced from cacao, which is pollinated by midges, and figs result from pollination by tiny wasps. I like chocolate and I like figs, but I wouldn't like to have to rely upon them for most of my non- starchy nutrition.
You may be thinking that we need not worry about any of this because our industrialized agriculture has an industrialized pollinator to take care of all our pollination needs: the western domesticated honey bee. But recent developments suggest that we cannot be so confident in this one major pollinator; hardly a week goes by without the media mentioning the problems faced by these bees and their keepers.
Concern about pollination and pollinators became so intense that the National Research Council (NRC) in the United States commissioned a report on the status of North American pollinators. The report, published in 2007, included a graph showing the change in the number of managed honey bee hives in the United States from 1945 to 2005. It's a scary graph. Apart from a few wobbles here and there, it shows a more or less continuous decline in the number of hives. If this downward trend continues unabated, there will be no honey bee colonies in the U.S. by somewhere between the years 2040 and 2060. Of course, this is somewhat absurd: the principle of supply and demand suggests that as the number of hives decreases, each one will become more valuable, and so the rewards for keeping them should increase. (But the report was written before the latest calamity to impact honey bees and their keepers, the mysterious colony collapse disorder, struck.) Still, I suspect that things might be worse than even the depressing scenario outlined in the NRC report suggests, as our need for pollination is increasing. A recent survey of food produc-
tion since 1961 shows that the number of pollinator-dependentfoods has quadrupled in less than fifty years. The same study noted that this increase far outstripped the rate of growth of the world's domesticated honey bee hives, suggesting that either wild honey bees (escaped, feral colonies) or other pollinators have been helping us without our being aware of it. This growing demand for pollinator-dependent crops could cause a crisis in pollination.
The increased need for pollinators is particularly acute in almond orchards. Almonds are a needy crop in terms of pollination, and every year over half of the honey bee hives in the entire United States are taken to California to pollinate this one crop. In 2005 there weren't enough hives available, so some bees were imported from Australia. The area of land covered by the crop is expected to increase by 50 percent over 2005 levels in the next few years, so the pollination needs of the almond industry will only grow. This single crop will soon require more than two mil- lion honey bee hives each spring. That's over 70 percent of all the managed honey bee colonies in the United States. Having most of the domesticated honey bee colonies in the U.S. gathered together in just one state for the pollination of just one crop sounds like a recipe for disaster.
The question of why American beekeepers are in such trouble is complex because so many factors have impacted the industry. It's depressing to consider the many issues that have emerged in the past thirty years. First there were the problems with African- ized bees—originally called killer bees (that epithet was dropped because it was considered too scary). The Africanized-bee prob- lem in North America had its genesis in the escape of a particular form of honey bee native to Africa. This strain was both aggres- sive and hard-working. Warwick Kerr, a Brazilian bee biologist, wished to crossbreed these bees with the domesticated variety that had been taken to South America hundreds of years earlier. The Brazilian bees were considered fairly peaceful but not very productive. Kerr hoped to transform the somewhat lazy Brazilian insects into harder-working bees through the introduction of genes from the African strain. He hoped that peaceful would beat out aggressive and that hard-working would beat out lazy in the genetic lottery of interbreeding. But in 1957, some Africanized bees escaped in southeast Brazil, a long way away from the almond growers of California. Living pests are not like pollutants, however, which can be turned off at source; once introduced, they reproduce and can increase unaided in both number and geographic range. Further- more, these increases are usually almost impossible to stop. The escaped African strain gradually took over most of South America, then Central America, then Mexico, and by the late 1980s, it was on the verge of invading the United States.
These aggressive bees are more time-consuming to manage than the other commonly used honey bee strains, and that can make a marginally profitable industry economically inviable. Consequently, the United States Department of Agriculture spent vast amounts of money trying to come up with ways of preventing the arrival of Africanized bees in the U.S. The invasion was stalled for a while because habitats at various points along the narrow Central American isthmus were unsuitable for the advancing occupation. But the inevitable eventually occurred, and the first Africanized bees in the U.S. were detected in Texas in 1990. They are now in almost every state along the southern margin of the U.S., as well as Nevada, Oklahoma and Arkansas; they reached Florida in 2002. They do not get in the news much these days; their economic impact was originally worse than their sting, and beekeepers have since had worse problems to overcome.
While the North American honey bee industry was anticipating the arrival of aggressive bees, nasty bee parasites—specifically, tracheal and varroa mites, both accompanied by a bunch of diseases— appeared. Tracheal mites are tiny parasites that live in the breathing tubes of bees (imagine having cockroaches crawling around inside your lungs). The debilitating effects of these mites on honey bee colonies were first noticed on the Isle of Wight, off the coast of southern England; the mites spread from there to the rest of the British Isles and then to other parts of the world. They reached North America in 1984. Tracheal mites are difficult to detect because they live inside the bees. In fact, beekeepers often don't know that these pests are in their hives until the infestation is so severe that the colony becomes considerably weakened. Once inside a colony, the mites will stay until eradicated. Recent methods for control of the mites involve putting sugar with vegetable oil or shortening into the hive. Greasing the bees in this manner makes it difficult for the mites to transfer from one host to another. This interesting approach at pest control doesn't involve the use of unpleasant chemicals.
There are two species of varroa mites, only one of which, appropriately named the destructive varroa, is causing large-scale problems for the honey bee. These large parasites can be found on the surface of adult bees or on pupae and larvae, where they suck the bodily fluids of their hosts. For us, they would be like a mosquito the size of a small dog attached semi-permanently between our shoulder blades, where we can't reach it. Originating on a different honey bee species in Southeast Asia, where they were first noticed in 1904, these natural enemies of domesticated bees were detected in North America in 1987. They can have a debilitating effect on colonies, and it seems that the almost complete disap- pearance of wild (as opposed to managed) honey bees in much of the New World can be attributed to them. The hives can be treated with formic acid, a chemical related to vinegar, to get rid of these parasites, but for obvious reasons its use is not recommended during honey production.
The other enemies of our industrial-scale agricultural pollinator include small hive beetles, wax moths (which eat the brood comb), at least two bacterial diseases, two fungal diseases and no fewer than eight viral diseases—one of which has been implicated in the latest round of catastrophes to affect honey bees and the people who keep them: colony collapse disorder, or CCD.
The main symptom of CCD is the mass disappearance of bees during the winter. Beekeepers inspecting their hives in spring find them almost entirely empty. CCD caused the loss of over 40 per- cent of the colonies in the U.S. during the winter of 2006–07, with some beekeepers losing more than 80 percent of their hives. Losses continue, with 36 percent of hives dying out over the winter of 2008–09. CCD has been blamed on everything from pesticide use to the bees being disoriented by signals from cell- phone towers; a recent headline read "Mobile Phones Are Killing Bees—Mankind Will Be Extinct in Four Years!" I favour this hypothesis for the simple reason that I do not like cellphones. But when pressed I will admit that cellphone towers were around for a long time before CCD was first detected, so the facts don't fit the hypothesis. Most recently, another bee disease, Israeli acute paralysis virus (IAPV), has been blamed for CCD. Its causative role has been demonstrated experimentally, but there are multiple strains of the disease and some seem to have little effect upon bees.
Another view is that CCD should be called MSD, or multiple stress disorder. Stresses on honey bees have increased for many reasons—not least because of the numerous treatments for the numerous ailments that now afflict them (being repeatedly doused with vegetable fat and vinegar would certainly make me feel less vigorous). A range of novel pesticides are now in widespread use in North America, despite having sparked lawsuits against pesticide companies by European beekeepers. Transnational transportation may also have had an effect. During their journey from crop to crop and state to state, the poor bees are exposed to multiple pesticides and other environmental contaminants, as well as the stress of travel. The bees are also given a series of different monoculture crops to feed on when they're being moved like this. How healthy would we be if in March we ate nothing but almonds, in April nothing but apples and in May nothing but blueberries? This is what we force many honey bees to do (albeit on the pollen rather than the fruit).
With this seemingly continual onslaught, we should have sympathy for our beekeepers. Not only have they had to cope with these nasty parasites and diseases, but they have also had to deal with very low prices for their product because the North American market has been flooded with cheap honey from overseas. (While being "flooded" with honey might sound nice, the quality of many imports is poor and they often have high concentrations of pesti- cide residues.) As a result, North American beekeepers now make most of their income from renting out hives for crop pollination rather than from selling honey.
Whatever the cause or causes of CCD, it is yet another indication that relying on just one organism to provide almost all our pollination needs is an unwise strategy. Just as we protect our finances by not putting all our funds into a single stock, we should hedge our pollination bets by not relying so heavily upon the activities of a single species.
There is another reason why concentrating our pollination efforts upon this one species is not a good idea. Please don't tell any beekeepers I said this, but honey bees are not always good pollinators. Your hypothetical breakfast is a case in point: honey bees are poor pollinators of alfalfa and some berries (blueberries, for example), and although they do a good job with watermelon, wild bees sometimes do the work well enough that honey bees aren't needed. Alfalfa flowers have a special mechanism that must be "tripped" by pollinators, and honey bees are not very good at getting this mechanism to work. Blueberries keep their pollen hidden inside minute anthers similar to salt shakers, and honey bees don't know how to shake the pollen out. Both of these crops are far better pollinated by wild bees than by honey bees. But as we shall see, all may not be well for these other bee species either.
It is these other bees that most interest me. There are over
19,500 described species; they are beautiful but largely ignored, and without their unseen activities, the world would be a far poorer place, aesthetically, ecologically, economically and nutritionally. It is not only the pollinating role of these unsung heroines (and it is the females that do almost all of the pollination) that makes them important. Wild bees are particularly sensitive indicators of the state of the environment. They are especially good at reflecting the state of environments that have been heavily modified by us; indeed, I believe they are better monitors of this than any other creatures on earth.
Environmentalists often point to declines in the numbers of birds and mammals as indicators of our negative impact upon the planet. Spotted owls tell us that we have reduced the Pacific coast rainforest to fragments that are too small; polar bears are beginning to tell us that we have caused too much arctic ice to melt; the giant panda can tell us that too much wild bamboo habitat has been turned into farmland. But large charismatic vertebrates like owls and bears (polar or panda) are the tiny tip of the iceberg when it comes to biological diversity. There are more species of bees than there are of birds and reptiles combined; there are approximately as many species of bees as there are of birds, mammals and amphibians put together; there are more species of bees and wasps combined than there are of plants. There is power in numbers. We can better estimate changes in ecological conditions with insects than we can with the more popular birds and mammals simply because there are so many more species to give us the information we need.
Most of the land cover of planet earth is already dominated by human activity through agriculture, silviculture and urbanization. We need to be able to discriminate between diverse, ecologically healthy habitats and the more severely stressed areas when both have already been considerably modified by our activities. This book is largely an attempt to outline why I believe wild bees are such superb organisms to use for these comparisons. We will have to take some diversions along the road, but fortunately, these diversions usually provide me with excuses to talk about bees, and I hope you will enjoy reading about them almost as much as I have enjoyed finding out about them.
Excerpt from Keeping the Bees by Laurence Packer © 2010. Published by HarperCollins Publishers Ltd. All rights reserved.