>
> >My concern is the repeated assertion by some that the bees' recovery from
> tracheal mites has some relevance to the varroa
> infestation....inappropriately  fueling  the dream of countless Bond method
> adherents that they will discover the holy grail of beekeeping...fully
> varroa adapted bees....in their backyard during their lifetimes.


After easily breeding bee stocks for gentleness, productivity, hygienic
behavior, and seeing how quickly colonies stopped dying from tracheal mite
after the initial invasion, I expected varroa resistance to be just one
more thing that could be easily bred for.

My first Bond experience was when varroa first invaded and wiped out nearly
100% of my colonies--I clearly couldn't afford to lose that many colonies a
year.

So then I tried importing every line of purported "mite resistant" stock
that I could get my hands on, and made the mistake of letting them
interbreed.  Don't waste your time!  I just got a bunch of lousy bees.

However, I *have* seen colonies that keep mites under control, and pass
that trait onto their daughters, but generally lose the trait(s) by the F2
generation (I don't use instrumental insemination).  So I know that varroa
resistance is possible.

So long as I could maintain pure VSH or Russians, they did pretty well, but
most still needed some treatment to control mites.  But when propagated via
open mating, they rapidly lose the benefits of their breeding programs.
 I didn't want to be dependent upon the purchase of II breeders each year.

So after some years of trying other things, I returned to the tried and
true of simply applying strong selective pressure to an established stock
(my local mongrels), and minimized input of outside genes (other than from
local feral survivors).

And rather than allowing colonies to die via the Bond method, I treat
colonies that are losing the battle.  But I maintain strong selective
pressure each season, selecting only about 25 breeders out of 1000 colonies.

I'm in complete agreement that it is unrealistic to think that one will
spontaneously experience the evolution of varroa resistant bees in their
backyard.

On the other hand, if one can find truly resistant survivor stock, there is
no reason that one could not continue to apply selective pressure.

As it stands, it *appears* that after more than a decade of selective
breeding (with open mated stock) that my bees are making some progress.
Many, if purchased by those keeping only a couple of hives in a yard,
survive without any treatment for a number of years (I do not recommend
this to my purchasers).

In yards with a couple of dozen hives, however,  most colonies pass the
acceptable mite thresholds by mid August if not treated.  So I would never
claim that I have mite resistant stock.

But I'm encouraged by the fact that I *have * observed that my cutoff
threshold for mite levels in my breeder selection has been steadily ticking
downward year by year.  And this season, I've found a number of colonies
that have maintained mite counts near zero by the first of June (as
compared to some adjacent test colonies from another breeder, which had
counts over 100).

In summary, I'm finding breeding for varroa resistance to be the toughest
challenge in my career.  But I've also seen the possibility of relatively
rapid success, as evidenced by the Baton Rouge breeders, and what appears
to be a degree of success in my own selective breeding program (hampered by
open mating).

At this point in time, after I've winnowed out the hype and exaggeration of
those purporting to have had success at breeding "survivor bees," I'm
getting the feeling that evolution is taking its expected course, and that
we are finally seeing bees starting to adapt to varroa.

But this will not happen in the operations of queen producers who never
allow mite levels to rise to a level from which one could select for
variation.  So I'm putting a lot of faith into those hobby and sideline
microbreeders, who by dint of sheer numbers and tenacity, may find local
survivor stocks from which we can propagate phase 2 of the evolution of
mite resistance.

-- 
Randy Oliver
Grass Valley, CA
www.ScientificBeekeeping.com

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