This whole discussion looks a bit off topic to me. What is really
killing the bees? Mites? Nope, it's virus. Mainly DWV. Mites are just
the vector, transporters of virus between bees. I think we should look
for how bees can handle the virus infection instead.

My personal experience is that the initial high numbers of mites in
the hives has declined, but virus infection remain or even increase.
The first years of varroa there were a solid layer of mites on the
sticky boards after treatment without seeing any virus damage on bees.
This year I haven't seen more than a few mites on boards, but do see
hives affected by DWV in August. And yes, I do backup treatment with
oxalic later to ensure there is no resistance to fluvalinate.

Varroa resistance - honey crop. There has long been known, at least on
this side of the pond, that the so called resistant Russian bees
didn't produce much honey. The reason is obvious; they have a lower
brood production, and thus a lower mite production. To breed for lower
mite numbers will probably also mean breed for less honey. There are
hives that can live with varroa. But is there anyone that can honestly
say they can breed for higher honey production without loosing the
bees ability to handle mite infection?  Now Dee, you are in a special
situation in the desert. Are there any others, commercial or semi
commercial beeks that has done it? And please, keep small cells out of
this.

If we are looking for better ability to handle virus infection, I
would think vitality is important. It is for us, should be the same
for our bees. All selection mean some inbreeding --> less vitality. I
see a problem here. If we inbreed to select for special traits like
grooming etc, we loose some vitality among the bees to handle virus.
Thoughts?

-- 
Regards

P-O Gustafsson
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