- Hi there, we're gonna talk about varroa mites today.
I've got Paul Kozak here the provincial apiarist for the Province of Ontario, and Paul's gonna
talk about the seasonal population dynamics of varroa mites, and we're gonna talk about
the importance of treatment and monitoring.
We've got two different methods of monitoring that we're gonna be showing you but first
off let's just talk about the varroa population dynamics.
Paul, what's one of the most important things that you think people should know about varroa
mites and beehives.
- A few things here Paul, I would say first of all if you've got a colony of honeybees
you've got varroa mites, and it's always a matter of managing those varroa mites.
Those varroa mites are always on the increase and it's key that that population of varroa
mites in that colony is managed.
Otherwise that colony will die.
We have research, actually that Paul, yourself you were involved in from the University of
Guelph honeybee research center that demonstrates very clearly that varroa mites will indeed
kill a colony if unmanaged.
Doesn't matter what people say on their blog on the internet good peer reviewed research
specific to Ontario demonstrates that quite clearly.
In addition to that, another important thing to know is that, so as I said before, the
varroa mites are always increasing, anytime that honeybee colony is producing honeybee
broad, so developing honeybees, that is allowing the varroa mites some protection.
So a large proportion, most of the varroa mites are in that broad.
They're protected from treatments at times, and they're also using that broad to reproduce
themselves and that's when they get on the increase.
So as spring opens up you start getting broad your varroa population immediately starts
to climb.
- Maybe you could mention a bit about varroa reproduction in drone broad vs worker broad.
- Yes, so drone broad has three more days than worker broad.
24 days as opposed to 21, and that makes a big difference in the life stage of varroa.
So varroa mites actually can, just roughly putting it, double the reproductive capacity
within drone broad.
The other thing is, keeping in mind that any time you have broad again those varroa mites
are on the increase.
It's also worth mentioning, and important to understand that varroa mites, as a season
progresses, they're population not only increases but it increases more dramatically.
So it kinda has an exponential population curve, and really starts to pick up steam
as you get towards the end of the season, and that's where you have to be really careful
that you don't have the varroa population overtaking the honeybee colony because you
can even get the varroa mites under control yet you still can have compromised and sick
bees.
Especially going into winter.
So you really wanna be careful, and that's where treatments come in.
- Right.
- So I know the focus of this is gonna be on monitoring, treatments are really the way
that you are gonna manage your varroa population.
There are other cultural control methods, but you wanna on a regular basis, suppress
and push down that varroa population so it doesn't overtake the colony and cause that
damage that University of Guelph has researched will kill a colony.
Monitoring comes in where that's really your tool for figuring out what are the levels,
when should you treat, what type of treatment should you use, and was it effective.
So it's really an important tool, monitoring, for figuring out where the varroa mites are
at.
- Right.
We see pretty big differences year to year based on the kinds of winters we have, the
kinds of springs we have and so on.
What times of year would you suggest if people are doing this monitoring, because we don't
really know what we have one year to the next.
It's quite variable.
- Yeah and I would say that to quote Les Eccles, the lead for the technology transfer program,
you can't bee keep to a calendar.
So varroa monitoring, even though we are promoting a special week on that, it's not like Saint
Patricks' Day, where everyday you go in and this is the day you're gonna...
Like you said, you got some seasons that are earlier and later.
So if you have an earlier spring, that might mean that you wanna monitor more early, your
colonies are coming out of winter earlier, and it also has implications for how quickly
that varroa mite population can increase.
As you know, anytime you get broad growing going, the varroa mites are picking up their
population.
To put it very basically, I think that there's, you got your opportunity in spring, summer
and fall to monitor.
Spring as early as you can, that's ideal.
If you are gonna be putting a treatment in during spring before the nectar flow, which
most bee keepers will have to, it doesn't hurt to actually monitor after to see if that
treatment was effective.
As you get towards the end of summer you wanna check those varroa mite levels again, again
at the very basic and you also wanna make sure that if you put a treatment on in fall,
which again most bee keepers are gonna probably have to do, it's a very good idea to monitor
afterwards, to figure out if that treatment was effective or not.
Treatments will reduce levels of mites but you always wanna make sure that their below
certain levels, I believe you guys are gonna be talking about thresholds later, and that's
key to understand, and the only thing worse than having varroa mite levels that were not
knocked down effectively by a treatment is not knowing about it and having the bees go
into winter that way.
- Right.
What happens Paul, if a colony isn't treated and the varroa population gets out of control?
- Well, the research from the University of Guelph has shown that that colony is much
more likely to die and the science has demonstrated that.
What we're hearing about now, and that bee keepers are reporting experiences and we've
known about this for awhile is that the whole concept of re infestation or some people have
referred to it as a varroa bomb So you could have one honeybee colony that's over run by
varroa mites and if that number is so high and that colony starts to crash and it's got
all those honey reserves and they are other colonies, either within the yard, but if you
got a neighboring yard where another apiary of another bee keeper three kilometers away,
those bees can easily come in, rob out those honey stores and the mites simply walk over
and jump ship and so this really gets to monitoring is important for the health of your individual
colonies, your individual operation, but bee keepers need to recognize that they're part
of a community and a population, and if they're not effectively managing their varroa mites
they could be harming another persons bees.
Even when that bee keeper's trying to do the right thing and doing everything they need
to.
When we talk about monitoring we can see that there's quite a few colonies here and I don't
think anyone is expecting that you're gonna monitor every colony, every time you go into
the yard.
You have to fit that into the schedule whether you're a hobbyist or a commercial bee keeper
Let's say very simply put three would be the bare minimum that you would wanna do that's
what we do in apiary inspections as a minimum standard, but something like five in a yard
of 30 colonies would probably be ideal.
You are gonna get variation, but it's important to recognize that you wanna get a regular
schedule of monitoring you wanna a proportion of the colonies you're operating with, and
you also wanna document that information.
If you're like me, you'll remember it really well at first and then maybe two days later
you'll say what were those levels again?
- Yeah, write it down for sure.
- Exactly
- Thanks very much Paul, appreciate that
- Thanks
- Your insights there.
Now we're gonna look at two different methods of monitoring for mites we're gonna use the
sticky paper with screen bottom board and alcohol wash as well.
Those are coming right up.
Thank you.