that what I have been saying but got rudely attacked for it.
They'll live successfuly for about four years until varroa mites (an import) are too large in number and wipes that colony out. Is what you actually wrote.
Just not true is it? Some know that some colonies live quite happily in equilibrium with varroa (per Chris for instance); some know that unless colonies are treated rather more than anually, their colonies most certainly will not be 'successfully' survive to that magical value and then magically collapse (with no warning?); FERA quotes typical threshhold limits and indicates levels at which the colony will collapse (but do not call it CCD) and also give typical time scales, I believe.
Then you scome along and are quite specific that a colony will live successfully for about 4 years and then collapse.
We also told, by Fera, that the varroa loadings increase by approximately double every month. Simple maths tells me that (some) of my colonies, unless treated will collapse next year, if indeed they survive the winter. Feral colonies do not get those treatments.
I did say that perhaps location is an important factor. I did point out that this was a general and not a specific question asked. And you think you were rudely attacked. Trouble is a lot of these questions need reading carefully and answering acurately.
As the damage threshold seems to vary, dependant on location (again FERA are clear and open about this), it would appear that not all locations are exactly equivalent in this respect. That may indicate, to those who read more widely, that some tests carried out may give different results/findings than others.
Let me remind you what you wrote, just one more time: They'll live successfuly for about four years until varroa mites (an import) are too large in number and wipes that colony out.
I am very sorry but I do not believe a feral colony, with an initial heavy varroa loading, will survive about 4 years ( is that + or - one month, 3 months, 1 year, two years?) - unless there are other factors which could make that statement equally worthless.