Concerning Developments in Canada

[Alastair]

The information is now out that here in NZ our mites are developing resistance to Bayvarol, with (from memory), 10 to 20 times as much active ingredient needed to achieve the same effect as when the product was first released.

Most commercials have already noticed this from results in their own hives, and have become reliant ever more and sometimes exclusively on Apivar. Question being, what would happen if or when Apivar fails.

Well, in Canada it has happened. Entire commercial beekeeping operations are being wiped out and at this time the beekeepers have no answer.

 

[Maggie]

Last mid June because of reinfestation in some hives I treated with Bayvarol. I did not put any more miticide in the hives until the last week of Feb 2022. I believe if there was resistance to Bayvarol the hives would not have been productive. When I put in the autumn treatment, I also added a sticky board and observed 24 hours later in some hives zero mites on sticky boards, in others only 1-3 mites. I am in Mid Canterbury.

I suspect I had to retreat in mid June because someone in the area had not treated mid Feb/March or bought in hives from a varroa infested area.

Just my thoughts and what I observed at the time.

 

[tristan]

Last mid June because of reinfestation in some hives I treated with Bayvarol. I did not put any more miticide in the hives until the last week of Feb 2022. I believe if there was resistance to Bayvarol the hives would not have been productive. When I put in the autumn treatment, I also added a sticky board and observed 24 hours later in some hives zero mites on sticky boards, in others only 1-3 mites. I am in Mid Canterbury.

I suspect I had to retreat in mid June because someone in the area had not treated mid Feb/March or bought in hives from a varroa infested area.

Just my thoughts and what I observed at the time.

at the moment we are continuing to see hives be abandoned which leads to reinfestation.
however we where epicentre of bayvarol resistance many many years ago now. i would not be surprised to see more of that crop up as beeks cut costs on treating hives.

 

[JohnF]

The information is now out that here in NZ our mites are developing resistance to Bayvarol, with (from memory), 10 to 20 times as much active ingredient needed to achieve the same effect as when the product was first released.

Alastair, the researcher who did this work was at pains to say this did *not* mean that Bayvarol was failing in beehives or increased resistance - this was tests done in the lab and there is some doubt if the methods used originally were reproducible?

 

[Alastair]

Oh thanks John I didn't know that.

However the bayvarol treatment I did season before last failed so badly I just re treated everything with apivar.

 

[Otto]

I would think that proactive beekeepers that have properly explored treatment options other than amitraz and synthetic pyrethroids will be just fine. There are other ways to keep Varroa in check. I have not used either of these for over three and a half years now and cannot see my self using them again.

 

[frazzledfozzle]

We haven’t noticed any resistance to either Bayvarol or Apivar so far.
we have the odd hive in spring that were treated later than others that had a lot of varroa on emerging bees but the Apivar sorted it out.

in my opinion there are three ducks that need to be in a row with synthetics.

treating on time every time.
using the prescribed amount of strips in the correct placement.
no abandoned hives nearby.

obviously the first two is up to us but the abandoned hives is an issue that will only get worse unfortunately.

 

[tristan]

I would think that proactive beekeepers that have properly explored treatment options other than amitraz and synthetic pyrethroids will be just fine. There are other ways to keep Varroa in check. I have not used either of these for over three and a half years now and cannot see my self using them again.

agreed, but its not as simple as that.
all those treatments have their own issues to deal with and generally lower efficiencies.
at small scale you can often work around that, but that becomes problematic to do at larger scales.
also there is the complication factor ie they are harder to do and requires more skill. so different beeks can get different outcomes.

for eg i'm trailing OAE at the moment and already found a major issue which stops us from using it.

 

[John B]

All power to those that can use alternative treatments and get away with it. I have tried many times and cannot get them to work consistently. I also had almost total resistance to bayvarol several years ago.I may try it again this year although I guess everyone around me has still been using it so they are probably Been breeding resistance.
In the old days most of us would have worked together but given that most of us hate a fair percentage of other beekeepers guts and for good reason nothing is going to happen and it will continue to get worse every year.
The effects of varoa are continuing to evolve and change and just when we think we understand it we get caught with our pants down. I freely admit to having made mistakes and to also have misinterpreted what has happened to other beekeepers with their hive losses as PBB and then a year or two later finding exactly the same problem in my own hives.
May you live in interesting times.

 

[Otto]

agreed, but its not as simple as that.
all those treatments have their own issues to deal with and generally lower efficiencies.
at small scale you can often work around that, but that becomes problematic to do at larger scales.
also there is the complication factor ie they are harder to do and requires more skill. so different beeks can get different outcomes.

for eg i'm trailing OAE at the moment and already found a major issue which stops us from using it.

What, you mean your "trial" using one hive during the peak of the season? How can you be surprised that the bees chewed them out a little quicker than what an optimal full length treatment period would be at this stage of the season? I genuinely hope you do not come to the conclusion you mention above based on that...

 

[Maggie]

in my opinion there are three ducks that need to be in a row with synthetics.

Frazzie - should be 4 ducks - good bee stock also

In the old days most of us would have worked together but given that most of us hate a fair percentage of other beekeepers guts and for good reason nothing is going to happen and it will continue to get worse every year.

Sad but true

 

[tristan]

What, you mean your "trial" using one hive during the peak of the season? How can you be surprised that the bees chewed them out a little quicker than what an optimal full length treatment period would be at this stage of the season? I genuinely hope you do not come to the conclusion you mention above based on that...

you missed the point.
i can't have bees chewing out treatments, even just 1%.
remember the amount of treating you probably do in 50 years of beekeeping is just one treatment for me and i need it to work perfectly every time, 1000's per year. i can't have the odd hive where it doesn't work. outliers are not acceptable.
to many commercial guys have lost a lot of hives trying it and unfortunately very few are saying why.

something like one hive chewing out strips early is a complete fail. you might get away with it being hobby or even semi, but not in large scale.
especially when its just a matter of finding a new substrate.

we did 2 year trail on thymol many years ago and found issues.
thats why i say its not as simple as just use other methods.

 

[southbee]

We used over the years thymol, formic acid, oxalic acid, lactic acid all in different forms and variations, at the moment we're giving the cardboard strips soaked in OA a go in a few sites. So far they're working well. But I agree with you @tristan, it does take more skill than popping Apivar or Bayvarol in the hives, there's more factors to consider and more variations and it takes some commitment, it's the extra work and the uncertainty with OA on a commercial scale which can wear one down. But then, sticking with the same old doesn't seem to be the answer either, so fingers crossed it'll keep working for us.

 

[Otto]

you missed the point.
i can't have bees chewing out treatments, even just 1%.
remember the amount of treating you probably do in 50 years of beekeeping is just one treatment for me and i need it to work perfectly every time, 1000's per year. i can't have the odd hive where it doesn't work. outliers are not acceptable.
to many commercial guys have lost a lot of hives trying it and unfortunately very few are saying why.

something like one hive chewing out strips early is a complete fail. you might get away with it being hobby or even semi, but not in large scale.
especially when its just a matter of finding a new substrate.

we did 2 year trail on thymol many years ago and found issues.
thats why i say its not as simple as just use other methods.

I'll ignore your first point that I have missed the point for now🙂
Second point, I am not a hobby beekeeper and no, you don't do more treatments in one session than I do in 50 years.
Third point. If you have read some of Randy Oliver's article you should be aware that he calls what you're looking for the next silver bullet, and I agree with him that at this point in time we have nothing close to this sort of solution for Varroa. You need to adjust your expectations a little. Your current treatments don't work that well so why set the bar that high for an alternative?
Fourth point. The unfortunate reason commercial beekeepers don't tell you why their oxalic treatments didn't work is that they don't know why. That is the problem with doing a half-assed "experiment" and aborting it part way through. You cannot actually draw any valid conclusions from it.
Fifth point. "Something like chewing out strips early is a complete fail". Again, you're expectations are unrealistic. Every beehive is different and there are gross and subtle differences between how they will respond. That is why as a beekeeper you need to be prepared to not necessarily treat them all exactly the same. Does every beehive you have always get fed the exact same amount of sugar? Do you put the same number of boxes on every hive and do they all collect the same amount of honey? The only reason beekeepers have the expectation that they can do everything exactly the same with every hive when dealing with Varroa is that our first treatment options were quite close to Randy's silver bullet. Unfortunately, we no longer have that option.
Lastly. Your point on thymol. I have never used it so won't comment on its efficacy. Given your conclusions from your "trial" with oxalic acid strips I immediately have doubts how thorough your trial with thymol was. And if it was thorough, you have just done exactly what you lament from other beekeepers who won't tell you why their oxalic treatments didn't work. You have said you tried it and found issues. There is no information there that another beekeeper could use as a starting point or to make any decisions from.

 

[Josh]

The solution is prospective randomised controlled trials.

But that’s a lot of work & expensive.

My biggest suspicion about OA is that industry hasn’t jumped on it… is it too cheap to make money? Is it too expensive to study & produce for any return? Have they got an ace up their sleeve that they’re hiding until the current treatments are toast?

 

[Alastair]

Fourth point. The unfortunate reason commercial beekeepers don't tell you why their oxalic treatments didn't work is that they don't know why. That is the problem with doing a half-assed "experiment" and aborting it part way through. You cannot actually draw any valid conclusions from it.

In my own case my "experiment" was not "half assed".
I have used oxalic strips on hundreds of hives and results were poor (they killed the mites but the damage to the bees was the problem). Because of this I tried, over several years, various strengths, mixes, and amount of acid per strip, plus various strip types, and various placement configurations in the hives and amount of strips. Never got a consistently great result with any of it.

I would use conventional treatments in a few hives at some of the sites so as to get a comparison and almost without exception the conventionally treated hives would out perform the OA/GL treated hives, often considerably.

I was already experimenting with oxalic acid before Phil H even had bees, I have given it fair shot. I have worked bees in the apiaries of other beekeepers using OA strips and seen the exact same issues, despite that at least one of these beekeepers was a vocal supporter on the internet of this method.

When I tried to get answers some years back on this forum I was just told nobody had seen any problems and I was lying. And then a bit down the track one of the people who told me that said on the forum he was going to spend a lot more money to do his autumn treatment with apivar. Why spend a lot more money I wondered, when he claimed there was no problem with the OA strips.

I realise that in all likelihood the synthetic pyrethroid and amitraz based strips will eventually fail us. So for many years I have been working with all the approved alternative treatments, and even a few recipes of my own. We have to do this. But have now got to the point that all this has cost me a considerable sum of money not in the cost of the treatments, but in lost income.

Some people don't see the lost income, because you may not miss what you never had.

The purpose of this post is not to discourage others from trying, we have to. But after everything I have done and seen, I believe there is a disconnect between what we get told on the net, and reality.

 

[Otto]

The solution is prospective randomised controlled trials.

But that’s a lot of work & expensive.

My biggest suspicion about OA is that industry hasn’t jumped on it… is it too cheap to make money? Is it too expensive to study & produce for any return? Have they got an ace up their sleeve that they’re hiding until the current treatments are toast?

If you want a publishable, definitive scientific answer yes. Beekeepers don't have that much use for those though...

I am just trying to point out that using it requires a shift in mentality. I don't think it is a treatment you can simply put in twice a year by the calendar and forget about. Dealing with Varroa long term is going to be a case of evolving how you do things as a beekeeper.

I am pretty certain that the bees take time to adjust to oxalic acid in the hive environment. My suspicion is that the microflora of the hive (gut bacteria etc) need to get used to it and once they do it actually starts working better and better in the hives (because there are less detrimental effects on the bees). I have no real way of testing this though (would be an expensive set of experiments to run and analyse). I am again pretty certain that for me, beekeeping (with respect to dealing with Varroa) has actually got easier in the last two seasons.

 

[Otto]

In my own case my "experiment" was not "half assed".
I have used oxalic strips on hundreds of hives and results were poor (they killed the mites but the damage to the bees was the problem). Because of this I tried, over several years, various strengths, mixes, and amount of acid per strip, plus various strip types, and various placement configurations in the hives and amount of strips. Never got a consistently great result with any of it.

I would use conventional treatments in a few hives at some of the sites so as to get a comparison and almost without exception the conventionally treated hives would out perform the OA/GL treated hives, often considerably.

I was already experimenting with oxalic acid before Phil H even had bees, I have given it fair shot. I have worked bees in the apiaries of other beekeepers using OA strips and seen the exact same issues, despite that at least one of these beekeepers was a vocal supporter on the internet of this method.

When I tried to get answers some years back on this forum I was just told nobody had seen any problems and I was lying. And then a bit down the track one of the people who told me that said on the forum he was going to spend a lot more money to do his autumn treatment with apivar. Why spend a lot more money I wondered, when he claimed there was no problem with the OA strips.

I realise that in all likelihood the synthetic pyrethroid and amitraz based strips will eventually fail us. So for many years I have been working with all the approved alternative treatments, and even a few recipes of my own. We have to do this. But have now got to the point that all this has cost me a considerable sum of money not in the cost of the treatments, but in lost income.

Some people don't see the lost income, because you may not miss what you never had.

The purpose of this post is not to discourage others from trying, we have to. But after everything I have done and seen, I believe there is a disconnect between what we get told on the net, and reality.

@Alastair
I am sure you've given it a pretty through go yes. Why it isn't working well for you while it is for me is not a question I know the answer to. As with many things in beekeeping it is very difficult to answer without some first hand experience of what you have tried etc. I am sure there will be at least subtle differences in efficacy related to climate, length of season etc but again, I have no experience with using them elsewhere in NZ.

 

[Alastair]

Also Trevor Gillbanks told me he has OA/GL strips in his hives 12 months of the year. He thinks it works well and has zero mites.

 

[JohnF]

I can't remember what I had for dinner last weekend . . but I do remember your oxalic trials @Alastair . If I recall, you had issues with them being too wet and essentially dripping? ie they weren't dried before use. I'm not throwing stones, but more to point out that there have been so many mixtures by beekeepers - either deliberately or inadvertently when some couldn't calculate percentages or the difference of weight/volume and volume/volume. Not to mention soaking/drying/not drying.
I am on record with others, saying when I come to try OA and strips then I'm going to follow @Otto 's protocol. You should be able to find his file in the Document section and I have passed his details on to a number of beekeepers.

I'm a hobbiest so I can't comment on the work involved with your scale @tristan . . . but without Bayvarol and relying on other treatments, what is your current hive loss to varroa or lack of alternative treatment for same?

I would say 'at risk of repeating myself' but then again, there's no risk because I definitely *am* repeating it - I firmly believe the use of oxalic acid strips would have been an ideal beekeeper-funded research project, had beekeepers not voted down the levy.

Interestingly, an economic modelling paper has just been published by Pike and others on the cost of hive losses:
https://www.tandfonline.com/doi/full/10.1080/00779954.2022.2146527