Let me reply to some questions and points raised in this discussion:

Brian: Can other posters from other regions confirm or deny this in their
area please?

Brian, in my operation, I started to see unusual losses 3-4 years ago when
my bees were in irrigated alfalfa.  Large losses of adult bees, poor brood.
No indication of pesticides.  Happened to others in the area.  I first
suspected spraying for mosquitos for West Nile Virus, and another large beek
also suspected the same, unbeknownst to me.  He suffered massive losses.
Upon extensive investigation, the mosquito spray hypothesis became weak.
However, the other beek had recently switched to stock from another
country--not sure if his losses were due to the switch, or led to the
switch.

In any case, he had thousands of colonies die all around my ten yards.  I
assume that my bees were exposed to his problem, and my bees followed suit
following his losses.

I would not necessarily call our losses CCD, but colonies either did not
build, or dwindled, or collapsed.  Drifts of dead adult bees on the ground
were noticable.  Yes, I checked with the sole spray applicator in the area,
plus county ag, plus mosquito abatement.

I was not yet testing for N ceranae, so could have been nosema due to poor
nutrition in alfalfa, perhaps coupled with a virus.  Don't know.

Bob: Also possibly their original nosema ceranae issues date back many years
as some of these beeks have been having dead out problems for around 5-6
years.

Yes, Bob, as noted above.  I wish that I had samples of bees from those
years!  But since I started testing, my alfalfa colonies have less nosema
than those colonies that I leave home in California dry conditions.
Although I said that nosema doesn't appear to be the prime killer, having a
new nosema in the bees all summer would certainly add an additional stress
to them, and make them more susceptible to (at least some) viruses.  I'm not
letting N ceranae off the hook--just saying that it alone may not cause
collapse, just as mites alone don't.

Bill: since it is a colony survivor behavior against a pathogen by infected
bees leaving the colony which would save the remainder of the unaffected
bees.

This sounds like a reasonable colony-level immune behavior.  I've mentioned
before that many dinks left to die before almonds this year rebounded later
on their own.  I've seen them clear up severe sacbrood unaided.

Bob:  The similarities between "disappearing disease" and CCD are eerily
similar.

Yes, which makes me wonder if the diseases are part of Pete's Red Queen
hypothesis.  Every so many years (perhaps associated with sun  or weather
cycles, Juanse), some combination of poor nutrition, nosema, a viral
mutation, and perhaps a cold snap eliminate the genetically no longer fit
colonies--leaving only those with immune systems adjusted for the new
pathogen combinations.  This would be simple host/parasite/pathogen
evolution in action.

If this is what is happening currently, it is exacerbated by several
additional parasites and pathogens that didn't exist in the U.S. forty years
ago.  And perhaps a shift in plant patterns due to climate change,
pollutants, or even sublethal effects of new pesticides and miticides.

IMHO, the agent that would tip the balance would be a new, or mutated
existing, pathogen--most likely a virus.  Jerry's finally released the fact
that his team has apparently found far more viruses in bees than has been
previously reported in this country.

So if the issue is indeed mainly viral, what can be done about it?

Currently, little directly, although there is ample research that has
demonstrated that a smart RNA virus lab should be able to produce a siRNA
virus-silencing compound that could be applied to colonies.

Indirectly, there are several things.  Address colony nutrition and keep
parasite loads low.  But the final solution will again lie in genetics.  The
surviving colonies likely already have the cure for the problem in their
genes.

Randy Oliver

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