I've been told that varroa mites can be detected by taking a hand full of
bees from the surface of the brrod nest and dropping them in a baggy filled
with a mild dish soap and water.  Shake the bag and then watch for mites to
drop to the bottom.  I did not know this until after I lost my hives.  I
assumed that I had a problem with mites because the hives were almost void
of bees.  There were no signs of foul brood and I had full supers of honey
on each hive.  The bees were strong in the fall.  Maybe someone else could
add more to detecting the mites or give us an alternate to the loss of bees
like this.
 
        I checked for trachea mites in the summer by collecting 50 bees from
the top of each hive and dissecting the thoracic trachea.  No mites were found.
 
                Ed Beary
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