Across the globe beekeepers continue to rely on various chemical treatments to manage Varroa mites. The use of chemicals is essential for a successful integrated pest management (IPM) approach to controlling mite levels. Researchers are continually assessing the efficacy of current mite treatments, developing novel treatment formulations and applications, and working with various companies and regulatory agencies to make these products available to beekeepers. This week’s blog will discuss a new product which was recently registered by the Canadian Pest Management Regulatory Agency (PMRA).
New Varroa Mite Treatment Product: VarroxSanTM
As part of
an integrated pest management approach to controlling Varroa mites, beekeepers
need to use a variety of chemical treatments and reduce reliance on a singular
product. Having multiple treatment options available makes it easier for
beekeepers to work different products into their IPM plan. Recently, the
Canadian Pest Management Regulatory Agency (PMRA) registered a new product for
Varroa mite management known as VarroxSanTM. VarroxSanTM,
developed and manufactured by Vita Bee Health Canada Ltd., contains the active
ingredient oxalic acid dihydrate (18.42%) and is administered using strips.
As specified
by the PMRA label, to treat colonies using VarroxSanTM, a beekeeper
can use a maximum of 4 VarroxSanTM strips per 10-frame box of bees. The
number of strips should be adjusted depending on the total number of frames of
bees, but never exceeding 4 strips per 10-frames (see table below).
|
Number Frames of Bees
|
0 – 2.5
|
3 – 5
|
6 – 7.5
|
8 – 10
|
|
Number of VarroxSanTM
Strips
|
1
|
2
|
3
|
4
|
Treatment of
bees with VarroxSanTM, as with any miticide product, should only be
provided after monitoring indicates mite levels are above the economic
threshold (1% or 1 mite per 100 bees). To treat, the appropriate number of
strips should be folded in half and hung over one comb frame within the cluster
of bees. For example, this may be a singular strip placed over frame 2, 4, 6,
and 8, again, considering the number of frames of bees within the box and
adjusting accordingly. Strips should be hung so that the bees can walk on the
strips, slightly away from the surface of the frames. Strips should be left
inside the hive between 42 days to 56 days, and must be removed after a maximum
of 56 days. After 42 days, strips should be repositioned to remain within the
brood cluster.
To give an
indication of cost, American beekeeping supply companies are selling a 60-pack
of VarroxSanTM for anywhere between $78.95 USD to $89.95 USD. The Canadian price is yet to be determined
but local beekeeping supply stores expect the product to be available shortly.
The product
label indicates that VarroxSanTM is a treatment option in spring,
summer and fall, indicating that the product does not have strict temperature
restrictions and is suitable for the variation of temperatures experienced
throughout the Canadian beekeeping season. A main benefit to beekeepers with
this new product application is that the label states that VarroxSanTM
can also be used with honey supers on. This will provide a summer Varroa mite
treatment option for beekeepers who are focused on honey production.
According to
Vita Bee Health, VarroxSanTM has an average efficacy of 96.80% based
on a number of studies conducted in various geographic and climatic conditions.
Additionally, Vita Bee Health states that oxalic acid dihydrate, active
ingredient, works as a contact acaracide that is lethal to Varroa mites, but
the full extent of the mode of action is not yet understood.
It is
important that beekeepers understand that VarroxSanTM does not
provide a new active ingredient to the Canadian beekeeping industry, but rather
a new application of an already registered active ingredient – oxalic acid
dihydrate. Oxalic acid dihydrate is already registered for beekeeper use by
administering through vaporizers or the dribble method. So, if beekeepers want
to use oxalic acid as part of their IPM it is recommended that they select one
of the delivery methods (strips, vaporization, or dribble) and alternate this
treatment with another product that has a different active ingredient (i.e.
Apivar®, formic acid, or essential oil products). There may be
opportunity for a beekeeper to use an oxalic acid product more than once per
season, especially if using VarroxSanTM mid-season, but beekeepers
do need to reduce reliance on a single active ingredient when planning for
treatments and alternate with products containing different active ingredients.
A reminder
that beekeepers should not apply more than one mite treatment simultaneously.
Therefore, VarroxSanTM, as with all miticides, must not be
administered during the treatment period of any other Varroa mite treatments.
Applying more than one product at the same time may interfere with the
chemistry of a product potentially changing efficacy or causing harm to bees.
Overall,
VarroxSanTM provides the industry with another Varroa mite treatment
option, and it is one of few that is allowed to be used with honey supers on.
Now that VarroxSanTM is registered for use in Canada beekeepers can
expect the product to available for use in Canada next beekeeping season.
Connecting with ATTTA Specialists
If you’d like to connect with ATTTA specialists or learn more about our program, you can:
visit our website at https://www.perennia.ca/portfolio-items/honey-bees/
Email attta@perennia.ca