Re. Formic Acid Tolerance Exemption
Roy Nettleback submitted an e.mail opposing the use of Formic Acid (FA)
in beehives. Your opposition is well taken but your reasons are
somewhat unreasonable. I should point out that I prefer no use of any
drugs or chemicals in beehives and surely FA is among the least
attractive. So why would I still be in support of its availability and
use?
Well, here in Canada we travelled through the whole gamut of getting the
product 'sheduled' (a slight variation from a full registration that
proprietary products enjoy). We had no love for FA but it is a product
that proved effective against varroa and that it would be a badly needed
addition to the extremely limited arsenal of products currently
available to combat the mite.
Fluvalinate remains a wonderfully safe and effective product (albeit
expensive). It is used worldwide and has become the choice control.
Because of its widespread and frequent use, beekeepers may take this
product for granted and become relaxed about its use. Using the product
other than label instructions and over extended periods of time will
lead inevitably towards increased tolerance, followed by outright
resistance.
Fluvalinate is a synthetic pyrethroid and varroa's reproductive
mechanism and life-cycle makes it likely that resistance will develop.
Closely related products such as flumethrin (commercially available in
Europe) may not offer an alternative because resistant varroa is likely
to have resistance to all thse closely related compounds. (Perhaps it
explains why no other chemical companies have initiated registration of
those similar products in North America).
With all our eggs in the "fluvalinate-control" basket, we have become
extremely vulnerable to a sudden and rapid spread of mites resistant to
the product. The question is of course, what will the beekeeping
industry do when this happens. Out of desperation, beekeepers will
jsut about dump anything into their hives to save their bees (and their
livelihood). We believe that FA is an acceptable alternative, even with
its negative sides. With careful use of FA as an alternative control
product, we may be able to extend the usefulness of fluvalinate for many
years.
We have learned over 5 years of use that FA does not pose a risk of
residue. FA is the simplest of all organic acids, breaks down readily
and occurs naturally in honey. In fact, some honeys especially
horse-chestnut, have unusually high levels of naturally occuring FA (up
to 600ppm!). A whole group of ants, the formicidae, have been named
after the product.
Natural occurance does not mean it is safe! At 65% (here in Canada we
have decided against 85% because of its hazardous nature) this product
can be handled effectively and safely, providing one uses common sense
and basic safety precautions are taken. (Prescription glasses or basic
safety glasses offer sufficient eye protection in the field. Rubber
gloves are needed and of course, always stand upwind).
During the initial period, we did have some measurable increases in
queen failure following FA treatments. However, since then this has
gone down because of improved application methods and by ensuring to
have younger queens in the hives. Especially recent developments towards
'slow-release' application methods using plastic vegetable bags
(perforated with tiny holes) containing a FA-soaked substrate prove
effective and reduce the risks of applicator exposure.
Again Roy, I share your distaste of using chemicals in our colonies. For
Canadian beekeepers I am only advocating its use when needed and in an
overall mite control program that includes fluvalinate. However, in the
era of mites it has become a mean world out there and without our help,
our beloved bees will not survive.
Paul van Westendorp [log in to unmask]
Provincial Apiarist
British Columbia
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