2011 varroa levels

[The Drone Ranger]

There is an American patented device called Mite Zapper or something which involves wires in the foundation being heated electrically.
The momma varroa is in the brood food snorknel up waiting, when the heat rises suddenly and kills it.
As far as I can tell reading between the lines the larva mostly gets killed as well (not good)

You may have used the type of hand warmer with the liquid which you click a disk or otherwise knock it and it then goes solid giving off heat for about 1hr.
The heat output is constant temperature around 50'C Max

My suggestion for truly organic control would be a thin version of the hand warmer in between two foundation sheets to form 1 complete comb.
At the time all the brood has been sealed trigger the reaction to give off the heat. Moma wont be at that end of the cell but junior the only male will be because he hangs out at the base of the cell on the 'Faecal Accumulation' waiting for the ladies (his sisters !!) to appear.

I wrote an article for Scottish Beekeeper some time ago including the formula for making your own DIY hand warmer contents.
Just a bit of fun really but in my own experiments varroa dropped onto wax cappings containing honey heated to just 40'C died almost instantly.

I also experimented with a sprayer and water at about 80'C which by the time it had produced a fine spray was detected at 40'C
Sprayed that on live varroa and it stunned them temporarily but they soon recovered

[Jimbo]

Hey DR,

Ever thought of going on Dragons Den with your hand warming varroa killer.

[The Drone Ranger]

Hey DR,

Ever thought of going on Dragons Den with your hand warming varroa killer.

Lol

I did think of building a box with good thermal properties (all the parts are available from RS components) and thermostatic control.

This was after a chat with a chap who was using frame trapping the queen as his varroa control.
He put the sealed brood in the freezer to kill the mites (and the brood)
This link to a pdf gives the full method http://www.google.co.uk/url?sa=t&sou...SJp6PA&cad=rja
It involves destroying a full frame of brood 3 times at 9 day intervals

This was so he could produce organic honey I believe, anyway I felt if he could have warmed the sealed brood to 4o'C for 24hrs, or possibly 42'C for a couple of hours the varroa would be dead but the brood should survive OK.

[The Drone Ranger]

regards low mite drops I am seeing the same thing but

On the SBA website www.scottishbeekeepers.org.uk/.../Beekeeper%20April%2009(2).pdf

Page 9 of 28 Wally Shaws article says
"The bottom line is, that I have not found
monitoring mite fall in July to be a useful
guide to the mite population in the hive as
subsequently revealed under treatment.
As an extreme example, a hive that yielded
0 (zero) mites during 7 days of monitoring
in mid-July, 4 weeks later produced a
fall of 6,000 mites under treatment"

I think as mentioned elsewhere that lots of varroa which drop end up as a tasty snack for something else.
Either way its better to be over cautious I think

[The Drone Ranger]

[/QUOTE=gavin;7081
What reasons do Bailey give for the failure of hygienic breeding? There has been a recent resurgence in interest in this thanks to the efforts of Sussex University. AFB resistance is a bit more complex than hygienic removal, just as Varroa tolerance is more complex than VSH. Early rapid death of an AFB-infected larvae might be important, then the whole thing can be ejected intact without spilling open the load of infective bacterial cells.
[/QUOTE]

Hi Gavin

Les Bailey stated that bees would develop resistance to diseases that they were exposed to over long periods.
He postulated that disease spores/agents/virus can be present at low levels in most colonies but an outbreak only occurs when an additional challenge say for example food shortage triggers it. Stress of some other kind might also result in the same problem.
I read an article by you Gavin in the SBA mag and I concluded that you were saying that EFB was only found in apiaries contiguous with ones where an outbreak had occurred sorry if I misunderstood that.


Now the AFB breeding for resistance program involved taking survivor colonies from an outbreak area to a breeding station in Iowa .
They bred from the queens and then sprayed their colonies with AFB they also sprayed some control colonies.
The controls all developed disease as did most of the 'resistant' group but not all.

More queens were bred from the survivors and the experiment repeated
This time slightly fewer of the resistant group developed disease but it still was only a very small proportion that didn't develop disease.

The project continued but no further improvement was made to resistance levels.

Bailey analysed the results and found that the results were statistically not significantly different from those obtained by carrying out the same experiment on non selected stock.
The conclusion was that although resistance obviously existed that the breeding for resistance programme had not succeeded in improving on the results achieved without any selection process.

The methods they chose seem to me to parallel the varroa breeding for resistance program being attempted by some beekeepers
I suspect the outcome will be similar unless they use complex line breeding where we all are locked into buying queens.
You are as likely to see resistance developing in bees who have been exposed to varroa and helped to overcome it (by treating) as in bees who have had no help.
Therefore non treatment would be dead end strategy with no gains

[The Drone Ranger]

Hey DR,

Ever thought of going on Dragons Den with your hand warming varroa killer.

If you ever have even a crazy idea it's best to get it out in print otherwise somebody can patent something similar and block everyone else from manufacturing it .
I was amazed how many bee equipment /devices are being patented (mostly useless) all the time.
Once it's in the public domain it can't be patented

[The Drone Ranger]

http://www.beedata.com/apis-uk/newsl...pis-uk0205.htm

ORGANIC METHODS OF VARROA CONTROL

There is a good coverage of all the methods here in this edition of apis-uk
including lactic acid which is an October treatment (if you have missed the boat with thymol) and also heat treatment is briefly mentioned using heated boxes in Germany

[Jon]

I just re read this thread where were most of the posters noted a low varroa drop in autumn - far less than usual.
In spring everyone was reporting little or no colony losses.
I wonder are those two facts related.
The winter survival figures for UK regions must be due out soon.
Will be interesting reading.

[Jimbo]

Hi Jon,

I had a low varroa drop, little colony loss and since then no Nosema detected using the PCR method, no traces of any pesticides in either wax or brood according to Keele University.

[Neils]

I still think varroa currently represent the biggest problem for Honeybees and beekeepers.

It's been dismissed before, but I still think that a shift in treatments and beekeeper education is playing its part. There are no silver bullet treatments in most places, you can't just slap in pyrethoid strips at the end of the season and ignore varroa otherwise. Certainly around our parts new and prospective beekeepers have that taught to them over and over and the module syllabus teaches the same; you can't ignore varroa, you need to use a system of IPM, keep monitoring and take action when appropriate, using numerous different techniques, not just slap some chemicals in at the end of the season and assume they're doing the job.

I don't think beekeeping is noted for it's dynanicism or reception to change, but it's also the hobby du jour and I think that is also playing it's part. Yes there are those who've bought the line that beekeeping is easy and their garden will flow with honey with minimal effort or that treating for varroa is "un-natural" but they, along with those who refuse to adapt are being culled from the beekeeping pool too. You have a whole generation of new beekeepers who don't remember the good old days, we've always had to monitor and treat for varroa. I think when SHB gets here we'll see something similar.

I think there is still much we don't understand about varroa, I've seen it opined recently that the widely held belief that Varroa prefer drone brood might not be true, for example (and if we over-cull drone brood, do we simply select for mites that happily breed in worker cells instead?). I do also wonder whether the shift from chemical treatments to ongoing IPM puts a different pressure on the mites? We've perhaps previously encouraged a lifecycle that encourages a rapid population expansion and collapse of the host colony to ensure that the mites can spread, IPM is a more tolerant approach: "you can live in the hives and as long as you don't cause a problem we'll leave you alone, start causing problems and we'll hit you from various different directions until you don't.".

before anyone starts shouting "prove it/quote some research" I don't have any, it's just one of the many things I ponder when I'm reading through things.