>   Further clarification (hopefully):
>
>   Virgin queens mate with drones from a good many different hives.  Simple
>rules of biology thus prevail.  If the vast majority of those nearby hives
>have been kept alive with Apistan strips, those queens on mating flights
>will likely acquire sperm mostly from drones that carry virtually no
>resistance to varroa mites.
>
>   By contrast, in an area without managed colonies (and where no one uses
>Apistan strips), queens will mate almost entirely with drones from colonies
>that somehow have resisted the depredation of varroa mites.
>
>   In other words, we must think in terms of a population of colonies, not
>in terms of individual colony tolerance of mites.
 
I agree largely with this and find your meaning perfectly clear.
 
It is, nonetheless, going to be a problem for honey producers, pest
controllers, and all sort of people. The PR for beekeepers will be bad,
as the public just do not generally like having swarms descending on
their homes and gardens. When you turn up to help them it often seems
that they blame you personally for what you can often be quite sure is
not from your bees. It is also part of our livelihood which flies off if
it is one of ours. However, I digress.
 
Your point about the general resilience of the bees, as an overall
population, is perfectly valid. In the case of heavily swarming strains
it may not even matter if ANY of the bees are varroa fighters. The
number of colonies out there will recover and varroa will not eradicate
bees in general. Individual colonies will, of course just go through the
normal varroa cycle of build-up, normal working, and collapse.
 
Thus I do not entirely agree with your point about the matings in feral
areas being with drones from colonies which have survived the mites, as
these drones, in the scenario under discussion, are likely to only be
from swarmy strains. In other words from a surviving overall population,
not from individual surviving colonies. It could even be that all
commercial operators will get out of such matings will be swarmy bees,
individually no better than their current stock at surviving varroa (on
a colony basis), and because of the management issues involved,
producing less honey.
 
Unfortunately hive management is about individual colonies, each one is
part of our livestock, and no-one likes to see them sick or dying.
Treatment will remain essential in economically viable -ups, and the
transition to swarmy strains will be a serious problem to such people.
Once truly resistant bees are found it will be a major challenge to the
next generation of queen breeders to get the swarming bred back out of
them, and incorporate all the other positive traits selected for over
the years.
 
I have read of eastern european beekeepers surviving varroa by
exploiting this swarming trait, but they need to run a higher number of
colonies than normal. A rule of thumb I have heard is that for every two
hives you ran before varroa you must run three after it to produce the
same results. Reason is that colonies collapse, and at any time there
can be up to 30% empty hives. These are just moved around with the full
ones and get occupied by swarms, thus replacing the losses. It is an
endless cycle of collapse and replacement. I can see it being
impractical in many areas though, as wax moths will quickly destroy the
combs.
 
I hope this thread runs for a while as it is adressing an issue of great
importance to most.
 
Kind regards to all from a somewhat cold and dull Scotland
 
Murray
--
Murray McGregor