I'm worried about the prophylactic use of anti-varroa medications.
There are two reasons.
 
1. The risk of resistance evolving in varroa.  This is probably
inevitable in the end but the longer it can be postponed the better.
It is particularly worrisome when only one leagal treatment is available
such as Apistan in the US or Bayvarol in the UK.  The rule should be to
treat only when necessary and then sufficiently to ensure eradication.
(Re-infestation is a separate problem.)
 
2. As far as I know, there is no known risk to humans from approved
miticides, at least in low concentrations, but consumption cannot be
a good thing.  This is why we avoid application whilst there are supers
on the hive.  Nevertheless, honey is moved around by the bees and
Bayvarol (I don't know about Apistan) is absorbed by the wax which can
then be consumed in the form of comb honey.  We may not be able to avoid
using these substances but it would seem prudent to use them only when
necessary.
 
It seems to me that monitoring is essential but treatment should be
reserved for cases where infestation has been diagnosed.
 
--
Malcolm Roe                            Phone  :  +44 442 230000 ext 4104
Crosfield Electronics Ltd              Fax    :  +44 442 232301
Hemel Hempstead, Herts. HP2 7RH, UK    E-mail :  [log in to unmask]
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