Sunday, June 17,
2007 The dead bees under Dennis
VanEngelsdorp's microscope were like none he had
ever seen before.
He had expected to see mites or amoebas,
perennial pests of bees. Instead, he found
internal organs swollen with debris and strangely
blackened. The bees' intestinal tracts were
scarred, and their rectums were abnormally full
of what appeared to be partly digested pollen.
Dark marks on the sting glands were telltale
signs of infection.
"The more you looked, the more you
found," said VanEngelsdorp, acting apiarist
for the state of Pennsylvania. "Each thing
was a surprise."
VanEngelsdorp's examination of the bees in
November was one of the first scientific glimpses
into a mysterious honeybee die-off that has
launched an intense search for a cure.
The puzzling phenomenon, known as Colony
Collapse Disorder, or CCD, has been reported in
35 states, five Canadian provinces and several
European countries. The die-off has cost U.S.
beekeepers about $150 million in losses and an
uncertain amount for farmers scrambling to find
bees to pollinate their crops.
Scientists have scoured the country, finding
eerily abandoned hives in which the bees seem to
have simply left their honey and broods of baby
bees.
"We've never experienced bees going off
and leaving brood behind," said
Pennsylvania-based beekeeper Dave Hackenberg.
"It was like a mother going off and leaving
her kids."
Researchers have picked through the abandoned
hives, dissected thousands of bees, and tested
for viruses, bacteria, pesticides and mites.
So far, they are stumped.
According to the Apiary Inspectors of America,
24 percent of 384 beekeeping operations across
the country lost more than 50 percent of their
colonies from September to March. Some have lost
90 percent.
"I'm worried about the bees," said
Dan Boyer, 52, owner of Ridgetop Orchards in
Fishertown, Pa., which grows apples. "The
more I learn about it, the more I think it is a
national tragedy."At Boyer's orchard, 400
acres of apple trees -- McIntosh, Honey Crisp,
Red Delicious and 11 other varieties -- have just
begun to bud white flowers.Boyer's trees need to
be pollinated. Incompletely pollinated blooms
would still grow apples, he said, but the fruit
would be small and misshapen, suitable only for
low-profit juice.This year, he will pay dearly
for the precious bees -- $13,000 for 200 hives,
the same price that 300 hives cost him last year.
The scene is being repeated throughout the
country, where honeybees, scientifically known as
"Apis mellifera," are required to
pollinate a third of the nation's food crop,
including almonds, cherries, blueberries, pears,
strawberries and pumpkins.
One of the earliest alarms was sounded by
Hackenberg, who used to keep about 3,000 hives in
dandelion-covered fields near the Susquehanna
River in Pennsylvania.In November, Hackenberg,
58, was at his winter base in Florida. He peeked
in on a group of 400 beehives he had driven down
from his home in West Milton, Pa., a month
before. He went from empty box to empty box. Only
about 40 had bees in them."It was just the
most phenomenal thing I thought I'd ever
seen," he said.The next morning, Hackenberg
called Jerry Hayes, the chief of apiary
inspection at the Florida Department of
Agriculture and Consumer Services and president
of the Apiary Inspectors of America.Hayes
mentioned some bee die-offs in Georgia that,
until then, hadn't seemed significant.Hackenberg
drove back to West Milton with a couple of dead
beehives and live colonies that had survived. He
handed them over to researchers at Pennsylvania
State University.With amazing speed, the bees
vanished from his other hives, more than 70
percent of which were abandoned by
February.Hackenberg, a talkative, wiry man with a
deeply lined face, figured he lost more than
$460,000 this winter for replacement bees, lost
honey and missed pollination
opportunities."If that happens again, we're
out of business," he said.
It didn't take researchers long to figure out
they were dealing with something new.
VanEngelsdorp, a sandy-bearded 37-year-old,
quickly eliminated the most obvious suspects:
Varroa and tracheal mites, which have
occasionally wrought damage on hives since the
1980s.At the state lab in Harrisburg, Pa.,
VanEngelsdorp checked bee samples from
Pennsylvania and Georgia. He washed bees with
soapy water to dislodge Varroa mites and cut the
thorax of the bees to look for tracheal mites; he
found that the number of mites was not unusually
high.His next guess was amoebic infection. He
scanned the bees' kidneys for cysts and found a
handful, but not enough to explain the population
decline. VanEngelsdorp traveled to Florida and
California at the beginning of the year to
collect adult bees, brood, nectar, pollen and
comb for a more systematic study. He went to 11
apiaries, both sick and healthy, and collected
102 colonies.
A number of the pollen samples went to Maryann
Frazier, a honeybee specialist at Penn State who
has been coordinating the pesticide
investigation. Her group has been testing for 106
chemicals used to kill mites, funguses or other
pests.Scientists have focused on a new group of
pesticides known as neonicotinoids, which have
spiked in popularity because they are safe for
people, Frazier said. Previous studies have shown
that these pesticides can kill bees and throw off
their ability to learn and navigate, she said.
Researchers have yet to collect enough data to
come to any conclusions, but the experience of
French beekeepers casts doubt on the theory.
France banned the most commonly used
neonicotinoid in 1999 after complaints from
beekeepers that it was killing their colonies.
French hives, however, are doing no better now,
experts said.
Entomologist Jerry J. Bromenshenk of the
University of Montana launched his own search for
poisons, relying on the enhanced odor sensitivity
of bees -- about 40 times better than that of
humans.When a colony is exposed to a new chemical
odor, he said, its sound changes in volume and
frequency, producing a unique audio
signature.Bromenshenk has been visiting
beekeepers around the country, recording hive
sounds and taking them back to his lab for
analysis. To date, no good candidates have
surfaced.If the cause is not a poison, it is most
likely a parasite.University of California, San
Francisco researchers announced in April that
they had found a single-celled protozoan called
"Nosema ceranae" in bees from colonies
with the collapse disorder.Unfortunately,
Bromenshenk said, "we see equal levels of
Nosema in CCD colonies and healthy
colonies."
Several researchers, including entomologist
Diana Cox-Foster of Penn State and Dr. W. Ian
Lipkin, a virologist at Columbia University, have
been sifting through bees that have been ground
up, looking for viruses and bacteria."We
were shocked by the huge number of pathogens
present in each adult bee," Cox-Foster said
at a recent meeting of bee researchers convened
by the U.S. Department of Agriculture.The large
number of pathogens suggested, she said, that the
bees' immune systems had been suppressed,
allowing the proliferation of infections.
The idea that a pathogen is involved is
supported by recent experiments conducted by
VanEngelsdorp and USDA entomologist Jeffrey S.
Pettis. One of the unusual features of the
disorder is that the predators of abandoned
beehives, such as hive beetles and wax moths,
refuse to venture into infected hives for weeks
or longer. "It's as if there is something
repellent or toxic about the colony," said
Hayes, the Florida inspector. To test this idea,
VanEngelsdorp and Pettis set up 200 beehive boxes
with new, healthy bees from Australia and placed
them in the care of Hackenberg. Fifty of the
hives were irradiated to kill potential
pathogens. Fifty were fumigated with concentrated
acetic acid, a hive cleanser commonly used in
Canada. Fifty were filled with honey frames that
had been taken from Hackenberg's colonies before
the collapse, and the last 50 were hives that had
been abandoned that winter. When VanEngelsdorp
visited the colonies at the beginning of May,
bees in the untouched hive were clearly
struggling, filling only about a quarter of a
frame. Bees living on the reused honeycomb were
alive but not thriving. A hive that had been
fumigated with acetic acid was better.When he
popped open an irradiated hive, bees were
crawling everywhere. "This does imply there
is something biological," he said.
If it is a pathogen or a parasite, honeybees
are poorly equipped to deal with it, said
entomologist May Berenbaum of the University of
Illinois at Urbana-Champaign.The honeybee genome
has only half as many genes to detoxify poisons
and to fight off infections as do other
insects."There is something about the life
of the honeybee that has led to the loss of a lot
of genes associated with detoxification,
associated with the immune system,"
Berenbaum said.
And so the search continues.
Many beekeepers have few options but to start
rebuilding. Gene Brandi, a veteran beekeeper
based in Los Banos, Calif., lost 40 percent of
his 2,000 colonies this winter.Brandi knows
plenty of beekeepers who sold their equipment at
bargain prices.Scurrying around a blackberry farm
near Watsonville, Brandi was restocking his bees.
Dressed in a white jumpsuit and yellow bee veil,
the exuberant 55-year-old pulled out a frame of
honeycomb from a hive that had so many bees they
were spilling out the front entrance."When
it's going good like this, you forget CCD,"
he said.
Hackenberg, who has spent his whole life in
the business, isn't giving up either. He borrowed
money and restocked with bees from Australia.In
April, the normally hale Hackenberg started
feeling short of breath. His doctor said he was
suffering from stress and suggested he slow
down.Not now, Hackenberg thought. "I'm going
to go down fighting."
This story appeared in The Daily Herald on
page A1. http://www.heraldextra.com/content/view/225743/
Today I spent an hour or three
Staring at a picture of a bee
It made me feel so happy inside.
Yellow black and furry
Making lots of honey
With no need to worry or hide.
I'd like to spend my hours
Rooting around in pretty flowers
Then flying home to service my queen.
Oh what a mighty buzz
Living in a healthy hive of love
A cog in one big busy bee machine.
Though I'm sure bees have their problems
Just like every living thing
Such as dying prematurely
When they use their only sting.
The constant threat of fumigation
And horrific nectar costs
Or bearing all the blame and shame
Of trouble caused by wasps.
What I think I'm trying to say
Is if I leave this heartless world today
I'm willing to return in bee form.
Collecting lots of pollen
From a field in Holland
And swearing my allegiance to the swarm.
Can't you see it's killing me?
I'm droning for the colony
I just want to be
A bee...
|