Honeybees have been dying in record numbers in the U.S. for at
least the past two years. Experts attribute the mass deaths to a
catchall condition known as
colony collapse disorder (CCD), although both a cure and the
culprit remain elusive. Despite as much as a 35 percent loss of bees
per year, we remain almost entirely dependent on what until recently
was a self-renewing annual population of billions of honeybees to
pollinate over 130 kinds of fruit and nut crops.
"We can't rely on the honeybee forever," says Blair Sampson, an
entomologist with the U.S. Department of Agriculture (USDA). That's
a problem, given that entomologists have yet to come up with a
viable alternative. But researchers report that another bee known as
the blue orchard, or Osmia lignaria, holds out promise of
filling in the void.
The blue orchard bee, also known as the orchard mason bee, is one of
3,000 bee species native to the U.S. and is currently the subject of
intensive study by the
USDA's Pollinating Insect Biology, Management and Systematics
Research Unit at Utah State University in Logan.
James Cane, an entomologist at the Logan bee lab, has been working
for 10 years to increase the availability of these bees and he says
there are now a million blue orchards pollinating crops in
California.
The reason these bees are considered the best potential honeybee
stand-ins, Cane says, is that unlike some specialist native species,
blue orchard bees, like honeybees, can
pollinate a variety of crops—including almonds, peaches, plums,
cherries, apples and others.
In just about every other respect, however, these bees are totally
unlike their European brethren. For one, they tend to
live alone. In the wild, rather than hives, they inhabit
boreholes drilled by beetles into the trunks and branches of dead
trees. When cultivated, they will happily occupy holes drilled into
lumber or even Styrofoam blocks.
The blue orchard bees also do not produce honey, rarely sting and,
owing to their solitary nature, do not swarm. They are incredibly
efficient pollinators of many tree fruit crops—on a typical
acre, 2,000 blue orchard bees can do the work of more than 100,000
honeybees. Their biggest drawback is that beekeepers can only
increase their populations by a factor of three to eight each year.
(Honey bees can grow from a small colony consisting of a queen and a
few dozen workers to a population of 20,000 foragers in a few
months.)
"We're still in the development stage of applying all the research
that has been done" by USDA's Agricultural Research Service, says
David Moreland, CEO of AgPollen, the world’s leading producer of
blue orchard bees for the California almond industry.
Of the nearly 700,000 acres (285,000 hectares) of almonds cultivated
in California this growing season, as many as 300 acres (120
hectares) were pollinated by blue orchards, according to Moreland.
Growers' inspiration for trying the new pollinator is simple
economics—last season they were paying up to $300 an acre to rent
honeybees, 10 times what they paid a decade ago.* This trend has
made blue orchard bees cost-competitive with honeybees, but only
barely.
"It's not clear we can [raise blue orchard bees on a commercial
scale] in a cost-effective way," says Karen Strickler, an
entomologist at the University of Idaho from 1993-2000 who has
worked with solitary bees and who currently distributes them to
beekeepers and hobbyists through the bee dealership
PollinatorParadise.com,
located in New Mexico.
Another solitary bee, known as the leaf-cutter, is the success story
on which scientists and beekeepers hope to model the trajectory of
the blue orchard bee.
"Ninety percent of all alfalfa seed in the U.S. is grown using the
alfalfa leaf-cutter bee for pollination," Moreland says. "That's
huge—that's an industry that over the past 25 years went from zero
to the preferred bee. So there's a model there that says: 'This has
happened before, it can happen again.'"
Cane, described by his peers as one of the world experts on orchard
bees, cautions that these bees currently can only supplement—and not
supplant—honeybees.
"The sheer number of bees you would need—at least 500 per acre (0.4
hectare)—it will never replace honeybees," says Cane. "That's an
outrageous number if you think about it."
AgPollen's Moreland is more optimistic. "If we got to the point that
we could not maintain populations [of honeybees]," he says, "this is
one way to ensure that the largest dollar specialty crop in
California for export—the almond—doesn't lose its pollinator."
*Correction (4/13/09): This sentence has been changed since posting. It originally stated the cost of renting honeybees was $300 per hive.
Comment:
It's an intriguing an interesting article, about an interesting little bee. It's sad, though, that instead of working to restore the honeybee, we're already looking for an alternative.
Humans and honeybees have maintained a fruitful and mutually-beneficial relationship for some three thousand years, it would be a moral tragedy if we betrayed that relationship now thanks to our own environmental poisons. A metaphor, perhaps, for the way we are betraying our relationship with the entire ecosystem.
We should be ashamed.
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