Hello friends.
On the Varroa mite and cell size thread.
I have been studying Varroa mites for the last 14 years with overabundance of
dedication and extending the scope of my studies to every little detail that I can
learn about about them because of their impact on the future of beekeeping.
Among the areas of interest that I have dedicated intensive research is the
mechanism of
invasion of the young larvae because it could/might offer a potential avenue to
combat them.  My observations have led me to believe that mites enter the cell
bearing the em-
bryos at the time when the bees go in to feed the larvae. The bees become
unwilling (?) means of transportation for their parasites as these deposit them in
contact with the young
larvae.  I am pretty sure of this fact.  I have yet to see free mites within
unoccupied cells nor in cells without larvae, hence, it seems that mites do not
just merely walk into the cells.  Although it is possible for Varroa mites to
enter the cells on their own volition since I have seen them walking on the
combs.  I tend to think that walking on the surface of the
combs occurs at the time when mites might be "switching" hosts.  Their hold on
their hosts
is tenacious (as demonstrated by degree of difficulty to remove them from the
surface of their host bees), thus not easily dislodged.  In my opinion, mites
arrive on the surface of the combs while holding on to their newly born (young
bees) and transfer over to other
bees after their arrival on the surface (since mites are observed on all age
ranges of bees).
Getting back to cell size:  It does not matter which race of bees we are talking
about. The nurse bees must be able to penetrate the depth of the cell to feed the
larvae and it is at this time that mites penetrate the cells in which the larvae
are growing.  The only remote possibility would be that if the cells were of such
a size that bees could just penetrate the confines of the cell, that the edge of
the cell would serve as a barrier to exclude the mites.  I would find that to be
almost an impossibility because of the anatomical area in which the mites at
usually found feeding (lower, rear abdominal area of the bees), hence
the mites would be beneath the folded legs of the bees and thus "protected" from
being
"scraped" away.  In summary, it seems to me that there is a probability of Varroa
mites
penetrating small cells regardless of the race of bees involved (as per the
reasoning given above).  I have seen mites in colonies with very small honey bees
and in the cells of very
large honey bees (relatively speaking).  I would tend to think that inability of
Varroa mites
to invade some races of bees (more or less) depends on other than cell size
factors.
I Sincerely hope that this will be taken in light of mere personal observations
with Varroa mites and having nothing to do with desire to take value away from the
observations of others who have made their opinions known in relation to cell
size.
I am very much interested in hearing about the experiences that others may have on
this subject. Please keep the thread alive.
Sincerely.
Dr. Pedro Rodriguez
Virginia Beach, VA