Hi Tom,
 
I've had Varroa floors on 2 out of 5 of my hives this year and have been
monitoring the natural mite drop every two weeks.
 
Points to note:
 
A) I thought that I had virtually zero Varroa infestation until I got
   my eye in.  Until I had seen a number of mites against the cluttered
   background of a floor insert, I just wasn't recognising the little
   devils - then I had a nasty shock!
 
B) The infestation level varies greatly between hives within an apiary.
   I consistantly get more than twice the mite drop from one hive than
   from the other larger colony.
 
C) Many of the mites found on the floor insert are still very much alive
   and readily climb onto the watchmakers screwdriver I use for poking
   around the debris.  The local bee inspector suggests that having a
   Varroa floor in itself helps as a control measure by stopping mites
   that drop from climbing back onto a bee walking across the floor.
 
D) There are all sorts of things I seen, in descending amounts......
   1-Wax, both old orange stuff and clear new unworked scales.
   2-Large amounts of dropped pollen loads.
   3-Hoards of miniscule mites?, far too many to count, bearly visable.
   4-Varroa mites in all conditions, live and "kicking", dark brown
     through to vary pale, some with a few leggs missing, chewed or
     dented, and sometimes only the curved outer shell.
   5-Bits of bee; antennae, legs, wings, heads.
   6-Fast moving eight legged pale oval mite?, 1/2 size of Varroa, I
     have sent a sample of these to the central sicence laboratory at
     the request of the local bee inspector.  I even found one of these
     with three tiny Varroa mites hanging off its leg joints.
   7-Wax month larvae, Oh how the love all that debris!
   8-Almost spherical jet black eight legged mite?, slow moving, 1/3 size
     of Varroa.
 
I'm afraid I don't know much about all this (15 month beekeeper), but I
hope this helps.
 
Cheers, Mike Pheysey.
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Oldbury-on-Severn
South Gloucestershire, UK.
(100 miles west of London)
 
51 degrees 39 minutes north
 2 degrees 34 minutes west
 
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