-- "Peter L. Borst" cited<[log in to unmask]> wrote:
> ...These comb cell size differences could affect the development of varroa populations; however, this possibility has been little studied. 

...but don't stop in the middle of a paragraph!  the paper continues:

"...In Brazil, as in other countries (Arnst, 1996; Coggshall and Morse, 1984), beekeepers have tried to make bees bigger than they are naturally by inducing them to build large comb cells from foundation wax stamped with cell patterns larger than they would make themselves naturally.  The relative benefit of natural versus oversized comb foundation has been a controversial subject for more than 100 years (Birkey, 2000)."

and following:

"A second frame contained a sheet of commercial wax foundation with Italian bee cell base spacing (cells about 5.4mm wide, inclding one ell wall).  This is the type of foundation normally used in Brazil."

if we are to believe the paper you cited here, it makes perfect sense.  varroa do better on larger comb, and Brazilian beekeepers have been upsizing the smaller sized AHB, and are now experiencing more varroa.  of course this isn't proof of anything, but it certainly is something to consider before jumping to the conclusion that the varroa in Brazil are becoming more virulent....in fact, the bees may be becoming a better host as their size is artificially increased.

deknow

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