by The Editors
September 2, 2009
News Newly hatched
honeybees in an almond orchard in Wasco, Calif.
The first alarms about the sudden widespread disappearance of
honeybees came in late 2006, and the phenomenon soon had a name:
colony collapse disorder.
In the two years that followed, about
one-third of bee colonies vanished, while researchers
toiled to figure out what was causing the
study published last week in the
Proceedings of the National Academy of Sciences surmises that
there may not be a single pathogen involved but a collection of
What have entomologists and beekeepers
learned in the last few years of dealing with the crisis? We asked
May R. Berenbaum, an author of the study, and other experts for an
the Crisis Treadmill
Rowan Jacobsen is author of “Fruitless Fall: The Collapse of the
Honey Bee and the Coming Agricultural Crisis.”
Thanks to the terrific gene sleuthing of May Berenbaum and others,
it looks like the pieces of the colony collapse disorder puzzle are
starting to fit together. And we can stop arguing about who was
the virus camp
the fungus camp
the pesticide camp
the varroa mite camp
the nutrition camp
It turns out everybody was
right. (Well, everybody except the cell-phone and microwave-tower
Colony collapse disorder and swine flu
are manifestations of
the same underlying issue: the global
diaspora of organisms.
The viruses compromise bees’ ability to
manufacture proteins, and proteins are the tools bees use to fight
off pathogens, to detoxify pesticides, to repair their cells, and to
meet all the world’s other challenges. If bees lived in an utterly
non-stressful world, they could go on despite the viruses. But of
course they don’t live in a world anything like that.
Even if we have at last identified the root cause of colony collapse
disorder, it shouldn’t give us any comfort. Just as knowing the
source of “swine” flu doesn’t help us cure it, identifying CCD will
not make it go away.
In fact, both diseases can be seen as manifestations of the same
underlying issue: The global diaspora of organisms.
just one of the many species we depend on that are struggling
mightily to withstand a steady stream of novel parasites and
pathogens they have never encountered before, and have no tools to
As the honeybee geneticist Tom Rinderer put it,
“What has happened to our bees? Jet planes have happened.”
we miraculously come up with solutions for
varroa mites, IAPV and
the latest threats to honeybees, there will simply be another “black
swan” that nobody could have predicted.
If anything, this latest news about CCD makes the problem more
relevant to the future, because it confirms what every holistic
systems thinker has been telling us. Honeybee health is inextricably
linked to the health of the entire environment, including our own.
If we can create systems of domestic food production that take their
cues from the cycles of nature, and let honeybees play the roles
they evolved to play, then the system will take care of itself.
But if we continue to push the system
farther and farther out of equilibrium by relying on chemical
shortcuts and fossil fuel intervention to fix the inevitable
breakdowns, then we will never get off the crisis treadmill.
Kim Flottum is the editor of Bee Culture magazine and the author of
“The Backyard Beekeeper” and “The Backyard Beekeeper’s Honey
pesticides, bacterial diseases and varroa mites have been implicated
in the search for the causes of colony collapse disorder. Plus,
viruses in conjunction with environmental stresses are suspects, and
University of Illinois scientists have discovered what occurs at the
genetic level of CCD. I suspect it is only a matter of time before
the pathogens are known.
Meanwhile, individual beekeeping operations have been damaged, some
beyond repair because of this malady. Others have been able to
recover. The overall picture is, however, not quite as bleak as the
press and the blogosphere might lead you to imagine.
in the U.S. show the resiliency of American beekeepers.
See the complete video "Silence of The
But beekeepers know that changes are necessary.
The changes involve
effective and efficient management of
varroa mite populations. A
beekeeper’s obvious first choice is to manage honeybee lines that
are resistant to or tolerant of these mites. But there is a very
limited quantity of these bees, and they are expensive. Or
beekeepers can choose a line of bees that tolerates mites to a great
degree, but differ in behavior from the bees they are familiar with.
Russian bees are resistant to the mites, but their seasonal
timetable is much different from that of the bees most U.S.
beekeepers are used to.
In particular, Russian bees require extra work in late fall and
early winter to accommodate the mid-winter almond crop in
California. Almonds bloom in February and March, much earlier than
any other major pollination crop. More than half of the bees in the
U.S. are used to pollinate almond orchards, and many, if not most,
migratory beekeepers depend on the crop for pollination income.
migratory beekeeping industry goes as the almond crop goes, and the
crop is suffering from water shortages, price fluctuations - and
beekeeper availability due to CCD and other forces.
The only alternatives to the use of resistant honeybees are chemical
miticides that effectively and efficiently control varroa mites
while they are in the hive. Newer products using essential oils are
safe, effective but labor-intensive, while traditional choices
require less labor but are less effective.
Reducing the insidious use of pesticides
on everything honeybees eat has been a
But for the longer term commercial
beekeepers have concluded that if they are going to succeed in the
migratory pollination business, they need to change and attend to
the discoveries made in the search for clues to colony collapse
High on beekeepers’ lists, besides controlling
Nosema ceranae, is reducing the
insidious pesticide barrage applied to everything honeybees eat, and
insuring that bees’ nutritional needs are met by feeding them better
food more often. These management changes have been rapidly accepted
and have lead to profound improvements in honeybee health.
The benefits? The pesticide abuse debacle in this country may have
finally come to a head, and discussions among beekeepers, the Environmental Protection Agency and agricultural
have begun (but is the new
EPA better than the last, and are
chemical companies on the level?). Plus, honeybee health has gained
more attention and made more progress in the last two years than the
last three decades. Better resistant bees are next in line.
But most important?
Awareness of the value of the beekeeping
industry in the production of the food we need is better understood
now than perhaps ever before.
Bias Against a
Joe Traynor is a bee broker for apiarists and almond growers. His
company, Scientific Ag, is based in Bakersfield, Calif.
The current consensus is that bee problems are caused by multiple
stressors. Bees, like us, carry viruses and harmful microbes all the
time. When we (and they) get run down, these nasties can take over,
making us sick. Colony collapse disorder peaked during 2007, which
was also a year, due to drought conditions in many areas of the
U.S., that good bee forage was in short supply.
As a result,
honeybees suffered nutritionally, making them more susceptible to
viruses (carried and transmitted by varroa mites) and to a new (to
the U.S.) fungus, nosema ceranae, believed to have been introduced
here in 2007.
developers, second-home buyers, corn
producers - and conservation purists.
Bee forage was more plentiful during
2008 and as a result there were less incidences of CCD (we won’t
know for a while how 2009 will turn out). Beekeepers that have kept
their bees in top shape nutritionally have had lower than normal
problems with colony collapse disorder.
There is no question that annual bee losses are far greater today
than they were 20 years ago. Twenty years ago, before virus
transmitting varroa mites were found in the U.S., 10 percent winter
losses were normal; now 20 percent losses are normal and losses hit
36 percent in 2007 (around 30 percent in 2008). Beekeepers have to
work much harder to keep their bees in good health than they did 20
This means paying close attention to nutrition, via
supplemental feeding of both proteins and carbohydrates, and
controlling both varroa mites and nosema (easier said than done as
there are limited means of controlling these two pests).
Natural bee forage, including some agricultural crops, is better for
bees than artificial supplements. Bees, like us, require a varied
diet to remain in top health. The ethanol boom has caused corn, a
poor pollen source for bees, to replace clover and alfalfa,
relatively good bee plants, in some parts of the U.S.
Increased urbanization, especially here in California, has resulted
in the loss of excellent bee pasture.
When baby boomers build a
second home in the foothills of California (or in Montana) they
don’t want any bees near their homes, so the first thing they do is
evict beekeepers from long-held locations.
Nature Conservancy removes honeybees
from its land because they originally
came from Europe.
Counterintuitively, the Nature
Conservancy has also contributed to bee problems.
purchases large tracts of undeveloped land for the laudable purpose
of preserving these tracts in their native state for future
generations. Unfortunately it has a policy of evicting all
non-native species from the property it acquires. This includes
honeybees since they are an introduced species, brought over from
Europe by early settlers.
The conservancy recently took over a large tract of land in San
Diego County that provided sustenance for many commercial bee
colonies. The bee colonies were evicted and are now competing for
ever diminishing bee pasture in the San Diego area (there are
probably 100,000 commercial bee colonies competing with each other
in San Diego County alone).
Evicting commercial (European) bees from Nature Conservancy holdings
is shortsighted as it creates a vacuum that allows Africanized
honeybees, which are prevalent in Southern California and are
becoming more prevalent in other parts of the U.S., to establish
themselves on the group’s property. The recent finding of fossilized
honeybees in the U.S. (thousands of years old but now extinct) may
cause the conservancy to change its policy, but beekeepers aren’t
holding their breath on this.
The costs of keeping bees in good condition to ward off colony
collapse disorder have increased dramatically over the past two
years. A main reason CCD has decreased this past year is that
beekeepers are spending much more time and money keeping their bees
Increased pollination fees for agricultural crops requiring
honeybees are paying for these increased bee maintenance costs.
May R. Berenbaum
May R. Berenbaum is a professor of entomology at the University of
Illinois at Urbana-Champaign.
A few things have changed with respect to colony collapse disorder
in the past year. First, whereas surveys conducted by the
Inspectors of America estimated CCD losses in America’s managed
honeybee colonies during the winters of 2006-2007 and 2007-2008 at
36 percent and 32 percent, over the winter of 2008-2009 losses
dipped to 29 percent, possibly indicating a decline in severity.
Secondly, an extensive survey conducted by researchers from two land
grant colleges, the U.S. Department of Agriculture and two Belgian
universities examined adult and larval bees and hive products from
almost 100 colonies for parasites, pathogens, pesticides and
nutritional factors. Although no single diagnostic difference was
identified, one consistent finding was that colony collapse disorder
bees were infected with multiple pathogens; over 50 percent of CCD
colonies, e.g., were infected with three or more viruses, almost
twice the percentage of healthy colonies.
Most recently, a whole-genome honeybee microarray analysis allowed
investigators from the University of Illinois at Urbana-Champaign
and the U.S.D.A. to examine differences in patterns of expression of
all 10,000+ genes in the honeybee genome, the sequencing of which
was completed in 2006.
Multiple comparisons of hives varying
geographically, temporally, and in CCD severity winnowed the list of
genes whose expression was most closely associated with the disorder
down to a handful representing fragments of ribosomes, the “protein
factories” of the cells, thus implicating ribosome breakdown as a
“root cause” of CCD.
Genetic material from common bee pathogens also on this microarray
revealed, as before, that CCD bees were infected with a greater
number of viruses, specifically picornalike viruses, all of which
cause infection by hijacking the ribosome, reprogramming the
“factory” to make viral proteins instead of honeybee proteins. Thus,
viral overload may lead to ribosome breakdown, which is manifested
Together these studies may explain why so many explanations
of colony collapse disorder seem plausible; in the absence of
functional ribosomes, bees would be hard-pressed to respond to any
of the multiple stresses to which they are subjected in 21st century
apiculture - pathogens, pesticides or nutritional deficiencies.
Detecting the ailment early might give
a chance to provide supportive care.
As for practical applications of these
findings, the most immediately useful product of the microarray
study is an objective genetic diagnostic indicator of colony
collapse disorder - the ribosome fragments. Such a diagnostic
indicator would be useful in determining whether other CCD-like
disappearances in England, Spain and elsewhere are in fact colony
collapse disorder or entirely different in origin.
Early diagnosis of the ailment might not be directly useful - there
are no vaccines to combat bee viruses and no known ways to patch up
broken ribosomes - but beekeepers who detect this breakdown early on
may be able to provide supportive care to help their bees recover.
Living With a
Marla Spivak is a professor of entomology and social insects at the
University of Minnesota.
All bees - honeybees and native bees - are still in decline, and it
is a serious issue. It is true there is less news coverage of bee
health issues, but bees are not faring better. Over 30 percent of
our honeybee colonies die every year, from colony collapse disorder
or other causes. Some native bumblebee species have become nearly
impossible to find, and we don’t know how many other native bees are
Beekeepers are treading water, replacing as many colonies as
economically feasible for their operations. Researchers are hard at
work using cutting-edge methods to determine why honeybee colonies
are collapsing and how we can mitigate the decline of all bees.
While bees may have faded from the news, they have not faded from
the public eye. In fact, the opposite has occurred. People are more
aware than ever about bees. The crisis has helped us understand the
importance of pollinators to our diet and environment and many
people want to know how they can help.
What can we do to help bees? Plant lots of flowers that provide
nectar and pollen for bees, and reduce pesticide use.
tangible and relatively easy actions, when implemented by many
people, can save our bees and restore health and diversity to our
agricultural and urban landscapes.
Needed - More
Diana Cox-Foster is a professor of entomology at Pennsylvania State
In the almost three years since the plight of honeybees caught the
public’s attention, we have learned that bees are faced with many
different obstacles, some naturally occurring (such as diseases) and
others that are byproducts of human activity.
The honeybees in the U.S. have been in trouble since the
introduction of parasitic mites (Varroa and tracheal mites) in the
late 1980’s. Varroa has continued to be the major problem, in part
because the mites have become resistant to the acaricides used for
Our study of hundreds of pollen samples
showed on average six different pesticides.
Do chemicals impair bees’ immune
Colony collapse disorder has severely
affected many beekeepers in the United States and caused some to go
We have learned much about CCD, but we are still a long
way from determining its exact causes and how to mitigate this
disease. Of major worry is that these same causes may be affecting
native insect pollinators. This translates into concerns not only
for security of our food crop production but also for the overall
health of the ecosystems that we depend upon for survival.
Data indicate that colony collapse disorder here in the U.S. has a
common set of symptoms that differ from colony losses associated
with late-summer or over-winter death. CCD colonies have elevated
levels of at least one of three closely related viruses: Israeli
Acute Paralysis Virus, Kashmir Bee Virus or Acute Bee Paralysis
The microsporidian parasite Nosema ceranae by itself does not
appear to be a major cause of hive mortality in the U.S.
Studies at Penn State indicate that Israeli Acute Paralysis Virus
can cause some of the symptoms of CCD. However, we think that stress
is an added major component and that other microbes and parasites
present in the bees play a role. Stresses such as sub-lethal
pesticide exposure and lack of adequate nutritional sources (pollen
and nectar) may be affecting the bees.
In hundreds of samples of
incoming pollen, a team at Penn State and the U.S.D.A. has found
that over 99 percent have at least one pesticide contaminant, on
average six different pesticides, and up to 35 different pesticides
in a single sample.
Over 100 different pesticides have been
Bees need more flower or pollen sources
What impact do these chemicals have on
bee health via impairment of bee’s immune system to fight off
diseases like viruses, through impact on bee behavior, or by
decreasing colony build-up and reproduction?
We have preliminary
data to suggest that all of these aspects are part of the problem,
but we do not know to what extent or exactly how, preventing
mitigation of this stress.
New approaches are needed to mitigate the problems in pollinator
health. It is clear that our recent recommendations to the
beekeepers are having a positive effect: sterilize the equipment
from collapsed colonies using gamma irradiation, use soft chemicals
to control Varroa mites and Nosema, and feed artificial pollen when
needed. Prior to CCD, these measures would not have significantly
affected overall colony survival. However, these are temporary
Band-Aids; these methods are costly and do not eliminate the
Beekeeping operations need sustainable solutions to stay in business
and provide essential pollination services. Needed are new strains
of bees with more resistance to diseases and parasites. The impact
of pesticides needs to be lessened.
Lastly, bees need more flower or
pollen/nectar sources nationwide.
In summary, we are a long way from
“solving” the pollinator crisis.