We are focusing a lot on pollinators/pollination and really need to address an important issue facing us today, Colony Collapse Disorder. In our Do Now today I asked the students what a world would be like without bees. As shocking as this world sounded, it may be a close reality. Read the following article and write a summary paragraph to earn 5 POINTS EXTRA CREDIT.
Where Have
All the Bees Gone?
More than one-fourth of
the honeybees in the United States have disappeared since last fall, and
scientists are trying to figure out why.
http://www.sciencenewsforkids.org/2007/06/where-have-all-the-bees-gone-3/
(condensed from original article to fit the page)
Inspecting a honeycomb from a healthy hive (above),
beekeeper Dan Geer finds bees densely packed. A honeycomb from a hive whose
colony is collapsing (below) has far fewer bees
Entomologists—scientists
who study insects—have a real mystery on their hands. All across the country,
honeybees are leaving their hives and never returning.
It doesn’t take long
before a hive is nearly empty. Researchers call this phenomenon colony-collapse
disorder. According to surveys of beekeepers across the country, 25 to 40
percent of the honeybees in the United States have vanished from their hives
since last fall. So far, no one can explain why.
Colony collapse is a
serious concern because bees play an important role in the production of about
one-third of the foods we eat, including apples, watermelons, and almonds. As
they feed, honeybees spread pollen from flower to flower. Without this process,
called pollination, a plant can’t produce seeds or fruits.
Now, a group of
scientists and beekeepers has teamed up to try to figure out what’s causing the
alarming collapse of so many colonies. By sharing their expertise in honeybee
behavior, health, and nutrition, team members hope to find out what’s
contributing to the decline and to prevent bee disappearances in the future.
Sick bees?
It could be that
disease is causing the disappearance of the bees. To explore that possibility,
Jay Evans, a research entomologist at the United States Department of
Agriculture (USDA) Bee Research Laboratory, examines bees taken from colonies
that are collapsing. “We know what a healthy bee should look like on the
inside, and we can look for physical signs of disease,” he says.
And bees from
collapsing colonies don’t look very healthy. “Their stomachs are worn down,
compared to the stomachs of healthy bees,” Evans says. It may be that a
parasite is damaging the bees’ digestive organs. The bees’ inability to ward
off such parasites suggests that their immune systems may not be working as
they should.
The honeybees have
other signs of troubled immune systems, such as high levels of bacteria and
fungi inside their bodies, says Dewey Caron, an entomologist at the University
of Delaware. He’s one of the leaders of the colony-collapse research team.
But why would
parasites, bacteria, or fungi in the body cause bees to leave their hives.
Caron says that some of these disease-causing agents may lead to disturbances
in bee behavior. “It may be that sick bees are not processing information
correctly and learning where home is,” he says.
If enough of the bees
in a colony can’t find their way home, he says, it’s just a matter of time
before the colony collapses. Being social insects, even healthy bees are unable
to live long on their own. And once the bees vanish, the crops that they
usually pollinate are in trouble.
Environmental clues
Another cause of
colony-collapse disorder may be certain chemicals that farmers apply to kill
unwanted insects on crops, says Jerry Hayes, chief bee inspector for the
Florida Department of Agriculture. Some studies, he says, suggest that a
certain type of insecticide affects the honeybee’s nervous system (which
includes the brain) and memory. “It seems like honeybees are going out and
getting confused about where to go and what to do,” he says.
Adding to the
mystery, Hayes says, is an observation about moths and other insects that
frequently use empty beehives to raise their own young.
“Usually, they move
right into an empty hive,” he says, “but now they’re waiting several weeks
before they do.”
Looking at bee genes
If it turns out that
a disease is contributing to colony collapse, bees’ genes could explain why
some colonies have collapsed and others have not. In any group of bees—or other
animals, including people—there are many different kinds of genes, because each
individual has a slightly different unique set of genes. The more different
genes a group has, the higher the group’s genetic diversity. And genetic
diversity is a plus as far as survival is concerned.
Some scientists are
now studying genetic diversity in honeybee colonies to see if it has an effect
on colony collapse disorder.
“If
a colony is genetically diverse, it’s less likely the colony will be wiped out
completely from a sweeping infection or disease,” says David Tarpy, a
University of North Carolina entomologist. That’s because at least some bees in
a genetically diverse group are likely to have genes that help them resist any
specific disease that gets into the colony, he says. He and his colleagues at
the USDA bee lab are currently running genetic tests on bees from collapsing
colonies. Their goal is to find out whether there are genetic differences
between the bees that vanish and those that remain in their hives.
Scientists are
working hard to figure out the causes of colony collapse. Meanwhile, bees
continue to disappear. Can anything be done to help them survive?
Tarpy suggests that
more people could raise bees to help restore their numbers. “Given this decline
in honeybees, if you want to get active in helping to promote pollination, the
best thing to do is to become a beekeeper and keep your own bees,” he says.
Don’t
be put off by the possibility of a sting, says Dan Geer, who raises bees in
North Smithfield, Rhode Island. First of all, beekeepers can wear protective
gear. And bees, he says, have a bad rep. “You’d be surprised by how gentle they
are,” he says.
