More about missing bees

Joe Shaw
Fri, 18 May 2007 16:41:17 PDT
Hi Gang,

The information below was published online this week, in AAA Science.  It is 
copyrighted so I just borrowed a few key paragraphs, and "cut" liberally so 
as to just post the flavor here without posting the article.  It was an 
interesting and long article, mostly discussing what is not known about the 
missing bees, and what the hypotheses are.


Conroe TX


Science, May 18, 2007, vol. 316, pp 970-972

Puzzling sudden losses of bees have happened before. In 2004, beekeepers had 
trouble with struggling hives sent to California for pollinating almond 
trees. And in the 1960s and '70s, before the arrival of mites, beekeepers 
around the country reported disappearing bees. ....Even an article in a bee 
journal from 1897--long before synthetic pesticides--describes healthy hives 
collapsing within a week, with the queen still there.

The main focus of Cox-Foster's working group is on nicotine-based compounds 
called neonicotinoids, which were first introduced as pesticides in 1992. 
One idea is that low doses interfere with a bee's ability to navigate back 
to the hive. And lab studies have shown that at least one such compound, 
imidacloprid, can kill bees at high doses.

There are few data that imidacloprid harms bees in fields, however. And 
other lines of evidence argue against blaming these pesticides.....

To assess whether pathogens explain CCD, Cox-Foster and her colleagues have 
collected samples from Pennsylvania of bees remaining in collapsed hives, as 
well as bees from nearby hives that were healthy or declining.


At the meeting, Cox-Foster presented some initial results. "We were shocked 
by the huge number of pathogens present in each adult bee," she says....

Some researchers suspect that an infectious agent may be spreading between 
hives via the wax combs and other equipment used by beekeepers. In February, 
Pettis and his colleagues took combs from CCD-affected colonies in Florida 
and gamma-irradiated or fumigated some of them before inserting the combs 
into hives with mite-free bees imported from Australia.

Adding to suspicions that one or more new pathogens are behind CCD are the 
results from a team led by Ian Lipkin of the Mailman School of Public Health 
of Columbia University, which has been doing high-throughput DNA sequencing 
of bulk bee samples from strong, weak, and recovering colonies. The bees 
from CCD-afflicted colonies have bacteria, fungi, viruses, and parasites 
that don't match any known bee pathogens and are not in the healthy 

Yet contradictory results have just come in from bee researcher Jerry 
Bromenshenk of the University of Montana, Missoula, and Bee Alert Technology 
and his colleagues. In December, they collected samples from hives in 
Florida. Preliminary analysis by researchers at the U.S. Army's Edgewood 
Chemical Biological Center in Maryland found similar viral burdens in 
healthy, failing, and collapsed hives...


Modern beekeeping itself, some suggest, puts the insects at risk. In the 
past 2 decades, as the United States started importing cheap honey from 
abroad, large beekeeping operations began to make more of their income from 
renting hives to farmers. California's almond growers, for example, pay a 
premium rate for pollination.

For bees, that means annual trips to California's central valley, where 
spring starts early and can be cold and damp. In October and November, more 
than 1.2 million colonies are trucked into California from all across the 
country and put into holding yards. Hives are normally inactive during this 
time of year. But the colonies need to be jam-packed with bees when placed 
into the flowering almond groves in February, so beekeepers feed them a 
high-fructose sugar syrup.

The syrupy diet may impair the bees' health, putting them on the verge of a 
colony collapse. "We can't raise feedlot bees," Ellis says. Pettis doesn't 
think the syrup is to blame but agrees that no one has hit upon a perfect 
nutritional formula yet..

Ellis and others suspect that the increased trucking of hives may also cause 
problems for bees. This concern is in part related to nutrition too; whereas 
bees in Nebraska, for example, used to spend winters in Texas with excellent 
forage, now they head for California. An abnormally dry season there means 
fewer wildflowers and less nectar, which weakens the colonies.

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