The new speculation is that the bee die-off is caused by globel 
cellphone antenna radiation. Here's one article on this (I think that 
genetically engineered crops that produce pesticides in every cell is 
the culprit, although both of these issues might be involved -- just 
a guess on my part):

from daily grist:

Buzz Light Year
Could cell phones be the culprit in honeybee disappearance?

   Apiarists in the U.S. and Europe have been scratching their heads for
months over rapidly waning honeybee populations. Now some scientists
who have combed through the data are all abuzz with a new theory: cell
phones. In bad news to mobile-attached ears, British researchers are
suggesting that phone radiation could be disrupting bees' navigation
systems. Research has shown that bees act differently around power
lines, and a recent study found that up to 70 percent of the little
stingers failed to return to hives that contained cordless-phone
docking units. The implications, of course, go beyond bee welfare;
Albert Einstein -- if not a bee expert, a relatively smart guy -- once
said that in the absence of the busy crop pollinators, humans "would
have only four years of life left." Ooh, that stings. Other theories
for the bees' departure have included mites, pesticides, global
warming, and genetically modified crops, but so far, none has been
definitively proved.

THE INDEPENDENT (U.K.)17 April 2007
Are mobile phones wiping out our bees?
Scientists claim radiation from handsets are to blame for mysterious
'colony collapse' of bees
By Geoffrey Lean and Harriet Shawcross

It seems like the plot of a particularly far-fetched horror film. But
some scientists suggest that our love of the mobile phone could cause
massive food shortages, as the world's harvests fail.

They are putting forward the theory that radiation given off by mobile
phones and other hi-tech gadgets is a possible answer to one of the
more bizarre mysteries ever to happen in the natural world - the abrupt
disappearance of the bees that pollinate crops. Late last week, some
bee-keepers claimed that the phenomenon - which started in the US, then
spread to continental Europe - was beginning to hit Britain as well.

The theory is that radiation from mobile phones interferes with bees'
navigation systems, preventing the famously homeloving species from
finding their way back to their hives. Improbable as it may seem, there
is now evidence to back this up.

Colony Collapse Disorder (CCD) occurs when a hive's inhabitants
suddenly disappear, leaving only queens, eggs and a few immature
workers, like so many apian Mary Celestes. The vanished bees are never
found, but thought to die singly far from home. The parasites, wildlife
and other bees that normally raid the honey and pollen left behind when
a colony dies, refuse to go anywhere near the abandoned hives.

The alarm was first sounded last autumn, but has now hit half of all
American states. The West Coast is thought to have lost 60 per cent of
its commercial bee population, with 70 per cent missing on the East

CCD has since spread to Germany, Switzerland, Spain, Portugal, Italy
and Greece. And last week John Chapple, one of London's biggest
bee-keepers, announced that 23 of his 40 hives have been abruptly

Other apiarists have recorded losses in Scotland, Wales and north-west
England, but the Department of the Environment, Food and Rural Affairs
insisted: "There is absolutely no evidence of CCD in the UK."

The implications of the spread are alarming. Most of the world's crops
depend on pollination by bees. Albert Einstein once said that if the
bees disappeared, "man would have only four years of life left".

No one knows why it is happening. Theories involving mites, pesticides,
global warming and GM crops have been proposed, but all have drawbacks.

German research has long shown that bees' behaviour changes near power

Now a limited study at Landau University has found that bees refuse to
return to their hives when mobile phones are placed nearby. Dr Jochen
Kuhn, who carried it out, said this could provide a "hint" to a
possible cause.

Dr George Carlo, who headed a massive study by the US government and
mobile phone industry of hazards from mobiles in the Nineties, said: "I
am convinced the possibility is real."

The case against handsets

Evidence of dangers to people from mobile phones is increasing. But
proof is still lacking, largely because many of the biggest perils,
such as cancer, take decades to show up.

Most research on cancer has so far proved inconclusive. But an official
Finnish study found that people who used the phones for more than 10
years were 40 per cent more likely to get a brain tumour on the same
side as they held the handset.

Equally alarming, blue-chip Swedish research revealed that radiation
from mobile phones killed off brain cells, suggesting that today's
teenagers could go senile in the prime of their lives.

Studies in India and the US have raised the possibility that men who
use mobile phones heavily have reduced sperm counts. And, more
prosaically, doctors have identified the condition of "text thumb", a
form of RSI from constant texting.

Professor Sir William Stewart, who has headed two official inquiries,
warned that children under eight should not use mobiles and made a
series of safety recommendations, largely ignored by ministers.

At 08:44 AM 4/18/2007, you wrote:
>That strikes me as most highly improbable.  By what mechanism would 
>you surmise that extremely dense uranium oxide particles be spread 
>worldwide, or even significantly outside the area where the weapons 
>were used?  And what evidence of radioactivity has been detected?
>----Original Message Follows----
>From: Jonathan Campbell <[log in to unmask]>
>Reply-To: Science for the People Discussion List
><[log in to unmask]>
>To: [log in to unmask]
>Subject: this may be very scary
>Date: Wed, 18 Apr 2007 08:26:20 -0400
>I've sent a memo to Leuren Moret, asking her if the bee collapse 
>might be caused by worldwide DU contamination. I think she's on 
>vacation or tour, she hasn't answered yet. Everything points to 
>toxic threshold phenomenon, and I suspect it might be DU. I hope I'm 
>wrong, would be nice if it's pesticide, then it's fixable.
>Exercise your brain! Try Flexicon.