I've read all this and so far I've avoided dipping my toe in the water ... I'm not sure that VSH bees are the answer ... there seems some evidence that once these bees are either moved to a diffferent location or the queens are used in another colony that there is limited transfer of the desired trait - certainly second generation queens, open mated, do not seem to rear bees with the same hygienic ability.
My bees have not been treated now for 10 years ... and before we start an argument I am NOT in favour of everyone following my path ... I have not lost excessive numbers of colonies and those I have lost I can honestly say were not heavily infested with varroa - I know because I regularly monitor my colonies with proper testing for varroa.
My bees survive and thrive, there are varroa present in the colonies, but they rarely get to the point where I have concerns. I don't see any diseases in my hives and they provide a reasonable honey crop. I've reared my own queens and I've bought in queens - currently the majority of colonies I have are small black bees but it's clear just looking at them there is a broad cross section of genetics as I do see mixed colours and sizes in all the colonies. Those colonies with queens they have raised themselves are no different - local mongrels.
Over a few years I've compared them with similar colonies, kept in similar hives and conditions - less than a mile from where I live but the only difference is that those colonies I have treated with OA by sublimation. I am confident that the treatment reduced the varroa load in those hives although - having tested them prior to treatment, the levels of varroa were largely the same as those in my own hives and subsequently yielded very similar levels.
I often ponder on why, when I hear reports of massive varroa loads, DWV etc. and dead outs in other colonies within my location, it is that I seem to get lucky ?
I have said it before, I can't prove it, but is it also to do with the way we keep our bees that some can survive without treatment and live alongside varroa ?
What do I do ?... Well:
1. My hives are highly insulated.
2. They have open mesh floors but the stands offer a skirt to prevent draughts
3. They are foundationless
4. They are lightly inspected (I don't fiddle with them .. inspections are brief, minimal and only for four reasons):
a) Are there eggs and is there brood
b) Is there signs of disease
c) Have they enough stores
d) Are there any queen cells
5. They feed, largely, on the stores they bring in - apart from a pre-winter top up if required.
6. I don't spring clean, I only change frames when it's really necessary.
7. I tend to only make increase when a colony is of a mind to swarm .. I don't continually break down colonies to make more colonies - and if I do, it's only with a frame or two of bees and a bought in queen or swarm cell.
On top of this they are kept in a semi-urban location so there is a wide variety of forage available from early spring until late in November. I suspect their foraging (because there is such a variety available within a short distance) is not on a very wide radius. My apiary is in a very sheltered position and the micro climate in the area is very mild.
So .. does this all contribute to a regime where the bees are able to cope ?
Do continual fiddling and aggressive varroa treatments lead to bees that are stressed and more prone to disease, colony weakness and a propensity to infestation ? Who knows ?
Perhaps we should all be testing colonies regularly for varroa and giving those colonies, where levels are demonstrably low, the opportunity to live without treatment whilst treating those where varroa levels appear to be unmanageable ?
When I worked in Africa I was very rarely bitten by mosquitos ...my business partner, when he accompanies me and was in the same location, ate similar food, drank similar things was plagued by mossie bites ... he would get up in the morning looking like a swarm of vampires had attacked him and at the same time I had no bites at all ? Why is it that nature can sometimes be selective ?
And... perhaps, varroa can be selective in the hosts they colonise ?
Who knows ?
he also found that the genetic line had become a lot narrower, with only some of the original pre varroa lines surviving meaning less genetic diversity which is never a good thing, at the same time he didn't really find any mite 'resistance' in his studies with colonies still dying out after a few years without treatment.
