I have an apple tree in my yard. For most of the fifteen years we've lived here, I've observed it full of honeybees when it blossomed in March or April. In the past two or three years, the number of honeybees has dropped quite a lot; last spring (2009) there were hardly any. Instead, it has been pollinated by quite a variety of wild bees. Fortunately, they are doing as good a job as the honeybees did, and the tree sets lots of fruit. Many commercial farming operations are not so lucky.
Every year in February about half the beehives in the U.S. are sent by truck or train to central California and, in a elaborate ballet, distributed at a rate of two hives per acre over a huge area devoted to Almond orchards. Whatever honey they may make is incidental to the pollination service they provide, for which the orchards' owners pay about $150 per hive.
There is little immediate hope for recruiting native bees to replace the honeybees' efforts. The almonds bloom for only a couple of weeks. The pollinators have to find other sources of nectar and pollen for the other 50 weeks of the year. A huge monoculture, essentially about 1,000 square miles of almond trees on bare dirt, is a bee's desert for those 50 weeks. While honeybees will fly a mile or so, most don't, and native bees will fly only a hundred yards or so. The middle of that huge orchard is perhaps ten miles from the nearest "native-bee-friendly" terrain. That may have to change.
A dreadful phenomenon has been reported just over the past four years, which is currently termed CCD, Colony Collapse Disorder. A beekeeper will find a hive without occupants…or several hives, or many. There are no nearby dead bees. There is honey in the hive, and strangely enough, no other bees have come to rob the unguarded cache. A World Without Bees by Allison Benjamin and Brian McCallum is the latest of a number of books that describe and attempt to diagnose CCD. These authors go further with a prognosis for human society that is already adapting to fewer honeybees, and may have to adapt to none at all. For example, the Chinese pear crop is now hand-pollinated, at least in Szechuan.
This little critter isn't a honeybee, but a leafcutter bee, of the genus Megachile. It is one kind of bee that works harder than a honeybee; while it takes 30,000 honeybees to pollinate an acre of almonds, 300 wild bees are sufficient. But wild bees are not manageable like honeybees. They are mostly solitary, and they start a new nest every year. This makes them resistant to parasites, but you can't make them go where you want. You have to attract them.Hmmm. This is one more area in which human hubris must make way for humility. We are headed for a new situation: we won't be able to just take our bees hither and thither. We'll have to woo the insects we hope will help us by pollinating our fruit, nut and vegetable crops.
But what has brought us to this point? There are several factors, and the scientific study of CCD and similar collapse disorders (the records of various kinds of "absent bee" problems go back 150 years) is still primitive. Science works best when you can determine a single, overriding factor that controls a phenomenon. We are much more poorly equipped to deal with multivariate problems. Multivariate analysis has been one area I have studied for decades, and take it from me, it is always hard, and often intractable.
We evolved to find, and if possible fix, a single cause: Saber-tooth Smilodon ate my first child. Kill Smilodon. Now it is safer to have another kid. If, instead, there is some combination of poor nutrition, this winter's flu, a festering sore here and there, so the child goes off her feed and dies of pneumonia, there is no single cause, and a desperate parent can do little but hold a dying hand. That was life for a quarter million years. Now, we have antibiotics (though they are of waning efficacy), which will stave off the pneumonia while the child's immune system deals with other threats. We think of the antibiotic as "the cure", when in reality it dealt with but one factor in a multivariate situation.
Pesticides are the antibiotics of agriculture. Economic entomology has largely been devoted to finding chemicals that will kill insects we don't like. For three generations, we've mostly ignored their effects on insects that we do like, or ought to. They are probably one factor in the decline of honeybees. A couple chapters of the book are devoted to recent "pesticide wars", primarily in Europe, where certain classes of pesticides are now banned and others are under scrutiny.
Other possible factors, each of which has a chapter, include pests such as parasitic mites (several kinds), parasitic fungi, bacterial and virus diseases, an impoverished environment because of monocropping (the 50-week-desert phenomenon I noted earlier), and the "management" (i.e. shipping) of beehives. In one place it was stated that there are about a dozen bee viruses of interest. Reflecting on human and veterinary medicine, it must be said that there are a dozen that we know about. There are 100 or more yet to be discovered or studied.
Put all the factors together, and what do you get? A puzzle we may be a long way from solving. But there is a root cause underneath all this: hubris. Human management of honeybees has become pervasive mismanagement. The "rise" of civilization, with cities and their crowded conditions, resulted in pandemics that just don't become a problem among more scattered peoples. The "bee cities" that result from common bee management practices foster the rapid spread of both diseases and parasites. We have created the conditions for bee pandemics.
Secondly, bees have been the victims of time management. Honey is their provision to insure against winters of variable length and severity. They also resume foraging each spring according to natural signals, such as temperature at sunrise or changes in humidity. Beekeepers want them to start working the same day each year, or to work year-round if possible. Beekeepers want the same (large) amount of honey per hive every year. The result is the difference you might see between the Platte River, with its meanders and slowly changing banks and diverse riparian habitat, and the Los Angeles River, with its straight run for the ocean between concrete walls. The narrowed schedule has resulted in reduced genetic variability, and bees that are less resilient when conditions get out of the beekeepers' control, as they often do.
Bees are not machines. People are not machines. Books like The Jungle by Upton Sinclair once decried the mechanization of humanity; movies like Metropolis publicized the same ills. This book is less of a polemic than those, but is a step in the right direction. In the meantime, there are a few things a body can do.
- Support the Xerces Society, which promotes reversing habitat loss, and planting of native-bee-friendly vegetation. Or look among the links on their web site for societies to support.
- Register with The Great Sunflower Project, grow sunflowers (Annual Lemon Queen only), and send in your reports of bee visits. They need a database of where bees of all kinds are, and are not, active.
- The NRDC also has a section on making your own garden bee safe.
There is a chance, maybe even a good one, that honeybees won't become extinct. Our shortsightedness works against our best interests, and theirs. Beekeepers will soon know, and some may already know, what percentage of their hives survived the winter of 2009-2010. You know that saying, "That government governs best, that governs least"? That also goes for management, particularly "management" of insect livestock.
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