I answered Peter Borst's posting off-line; he'd noted that he checks for 
mites in his strongest hives. I thought his response of general interest 
and copy it here:

On 10/1/07, Mea McNeil <[log in to unmask]> wrote:
 > > On the face of it, this seems to not make sense -- but this is what 
I do.

 > > Peter, It makes sense to me, as the mites are reproducing in a larger
 > > number of brood cells. Mea

Hi Mea
What I meant was, it doesn't *seem* to make sense to look for mites in
the best hives, since one might think that these would be the best
able to defend themselves.

Unfortunately, a big strong happy hive is perfect for mites to thrive
in, and they quickly get the better of them. A lot of times a hive
that is pretty far gone from mite damage won't even have all that many
mites in it, giving a false reading.

I suppose the mites may start to jump ship as the colony fails -- but
who knows? Nobody has really studied the movement of mites between
colonies.

pb

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