Despite serious losses to colonies in the U.S. and Europe, honeybees are on the rise in other parts of the world--although hardly keeping pace with growing demand
Katherine Harmon, Scientific American 18 May 09;
Even as U.S. honeybee populations have been hit hard by colony collapse disorder in recent years, domesticated beehives have been thriving elsewhere.
In an analysis of nearly 50 years of data on bees from the United Nations Food and Agriculture Organization, researchers found that domesticated honeybee populations have increased about 45 percent, thanks in large part to expansion of the bees into areas such as South America, eastern Asia and Africa. The results appear in the latest issue Current Biology.
The overall increase, however, is not what surprised Marcelo Aizen, a professor at the National University of Comahue in Buenos Aires, Argentina, and lead author of the study. Instead, he was taken aback by the sixfold increase in the growth rate of crops that depend on domesticated bees for pollination.
Booming demand for honey and a rise in foods that depend on bees for pollination are fueling the increase in bee colonies.
Many food staples, such as wheat, corn and rice, don't need bees. But plenty of fruits and vegetables that are now mainstays—from apples to zucchini—need help from pollinators like bees.
Demand for royal jelly, bee pollen and propolis (bee glue) has also contributed to the rise in beekeeping in some places, notes Eric Mussen, an apiculturist at the University of California, Davis, who wasn't involved in the study. But it is honey that accounts for most of the growth for bees across the globe.
The common domestic honeybee (Apis mellifera) was brought to the New World from Europe in the 17th century. Since then it has been responsible for keeping many crops (which were also imported) bountiful.
As the mysterious collapse disorder continues to claim hives by the hundreds—threatening, in particular, the almond industry—more attention is being paid other pollinators, including other types of bees such as solitary bees and feral honeybees.
Aizen explains that although "honeybees are the most frequent pollinator, they're not necessarily the most efficient." He points to the proficiency of local pollinators, such as bumblebees, to take care of crops such as squash and cucumber.
Paradoxically, as more land around the globe is put to agricultural use for pollination-dependent crops, indigenous bee species get crowded out. And as the native pollinators go, so, too, might some local floras that need specialized pollination, the study authors note.
Both Aizen and Mussen see this as an important time to reevaluate global food needs and goals. If healthful, pollination-dependent fruits and vegetables are to remain an important constituent of human diets worldwide, Mussen notes, more land—and even more pollinators—will be necessarily.
And although the overall growth in the world honeybee population might sound an encouraging note, Aizen remains cautious. "I think that there is a problem," he says about areas where their populations are shrinking. "I'm not saying that there isn't a problem…. But I think that we should change the perspective of the problem so it's not a question of supply but a question of changing demand."
