Blane said "The real numbers are considerably less than 3 daughter mites per mother per brood cycle.  The most published numbers are in the 1.6 - 1.3 range which frankly is a pretty low reproductive rate for a mite."

Blane is, of course, correct.  HOWEVER, I believe Blane's numbers are an average of mites produced in both worker and drone brood.  Drone cells are capped for 3 days longer than worker cells, and that is why the mites prefer them.  If conditions are perfect, which they seldom are, I understand a female can produce three daughters in drone brood; and can always produce two daughters (concerning only the time available).  My understanding is that in worker brood it take perfect conditions to produce two daughters and more normally only one can be produced.

With numbers like 1 in worker brood and 2 in drone brood, it is clear why mites have evolved to prefer drone brood.  Keep in mind that females live long enough to go through 3-4 entire cycles, and that more than 1 female may be in a cell when it is sealed...you can see why numbers of mites explode in late summer!

Lloyd
Lloyd Spear, Owner of Ross Rounds, Inc.
Manufacturer of round comb honey equipment and Sundance pollen traps