What caused my colonies to fail?

[JamezF]

The essence is that horizontal transmission of DWV from bee to bee is harmless. Varroa vectored DWV is lethal

Thank you for the links. I've only quickly scanned the documents, but if I have the gist correctly they appear to be suggesting that the form of DWV found in varroa-free bees is relatively benign, but when that virus enters the varroa mite it reproduces there in such a way that makes it far more damaging to the bees when it re-enters their system.

So DWV is not just a virus (or group of viruses) targeting honey bees, it's also a virus targeting varroa mites, and the mites don't just potentially transfer the virus from one bee to another, but provide an environment where it can reproduce, mutate (if that's the correct term to use in this case) and be reintroduced to the bees in its new more aggressive form.

That's certainly not inconsistent with my understanding of how viruses can work. I've not yet seen anything about an interaction with any other viruses the bee might be carrying, but I'll read more thoroughly later.

James

 

[Erichalfbee]

Thank you for the links. I've only quickly scanned the documents, but if I have the gist correctly they appear to be suggesting that the form of DWV found in varroa-free bees is relatively benign, but when that virus enters the varroa mite it reproduces there in such a way that makes it far more damaging to the bees when it re-enters their system.

DWV exists in many different variants. In the colony not exposed to varroa these variants exist in balance with each other in small numbers and are benign being passed from bee to bee.
What happens in varroa is that one or two of these variants become dominant and as such are pathogenic.

 

[Do224]

Just been to check the inspection tray, 24 hrs after yesterday’s vape. Real struggle for me to distinguish mites from other debris...maybe you guys can tell better...(the propolis around the perimeter of the tray has been there ages, but other than that it was wiped clean prior to vaping yesterday)

 

[oliver90owner]

I’ve got the same mask (without the visor) it’s from 3M the filters protect you from all organic acid vapours. Just love Walter in that series!

There we go again. Oxalic acid inhaled from sublimating bees is most definitely NOT a vapour.

Oxalic acid vapourises (without going through a liquid phase) around 160 Celsius. It also condenses vack to a solid at that same temperature. By the time any oxalic leaves the hive, it will be as solid, not vapour. You would be breathing in solid oxalic acid as dust particles.

 

[StephenT]

Just been to check the inspection tray, 24 hrs after yesterday’s vape. Real struggle for me to distinguish mites from other debris...maybe you guys can tell better...(the propolis around the perimeter of the tray has been there ages, but other than that it was wiped clean prior to vaping yesterday)

View attachment 30001View attachment 30002

They’re the darker non-circular disk shaped things with a couple of antennae or suchlike sticking out. Quite easy to spot once you get the hang of it.

 

[simonwig]

Real struggle for me to distinguish mites from other debris.

Hi

Very few that I can see, I've circled a couple on the attached.

Simon

 

[Do224]

Hi

Very few that I can see, I've circled a couple on the attached.
View attachment 30003
Simon

That’s useful, thanks Simon.

Not sure what to make of it then? I was expecting to see loads of mites if we’re thinking it was varroa that destroyed the other colonies...the hives are all close together with only about 18 inches between each one.

I used a gas vap to vape my bees whereas the other guy used a wand type device. I’m pretty sure I used the gas vap properly (it was my first time using it but I did a test run outside the hive first and all seemed well). If anything I left the nozzle in the hive for longer than the recommended amount of time....probably just over a minute. I can’t imagine this would make it less effective though....?

 

[Newbeeneil]

There we go again. Oxalic acid inhaled from sublimating bees is most definitely NOT a vapour.

Oxalic acid vapourises (without going through a liquid phase) around 160 Celsius. It also condenses vack to a solid at that same temperature. By the time any oxalic leaves the hive, it will be as solid, not vapour. You would be breathing in solid oxalic acid as dust particles.

I recently grabbed a mask from my bee shed to carry out vaping on a couple of my hives in my garden and during the task I was hit in the face a couple of times by a big puff of vapour/particles without any discomfort. It wasn't until later that I realised it was my A1P2 mask. I assumed it was the fact they must be quite large particles that made the mask effective.

 

[BeeGiner]

DWV exists in many different variants. In the colony not exposed to varroa these variants exist in balance with each other in small numbers and are benign being passed from bee to bee.
What happens in varroa is that one or two of these variants become dominant and as such are pathogenic.

I'm sorry Dani, I just don't buy it. This is just not the way viruses work.

A much more likely scenario, IMHO, is the DWV is much more damaging to bees that have been weakened by varroa.

 

[Erichalfbee]

Suit yourself. I’m not a virologist. Why don’t you message David Evans.
How do you explain that the variants of DWV virus found in varroa naive bees are many and found in low numbers while in those parasitised the number uf variants are just one or two and are present in huge numbers ?
His papers are here
https://www.researchgate.net/scientific-contributions/David-J-Evans-70322023

 

[Erichalfbee]

But like I said earlier. Bees’ demise due to varroa/DWV is multi factorial.

 

[BeeGiner]

Hmm, that sounds rather incredible to me, can you show us proof (not just wrong conclusions you have made)

So my conclusion is wrong because it is at odds with yours jenkinsbrynmair, no surprise there

You really need to look at this: Varroa destructor feeds primarily on honey bee fat body tissue and not hemolymph

 

[Wilco]

So my conclusion is wrong because it is at odds with yours jenkinsbrynmair, no surprise there

You really need to look at this: Varroa destructor feeds primarily on honey bee fat body tissue and not hemolymph

Think most on here are aware of the feeding on fat tissue. He's questioning your assertion that that is the main issue with varroa rather than the viral vector effect being the major issue. It's likely a combination of both.

Must admit that the idea of virus variants out competing each other is a bit of an intriguing one depending on the mechanism being suggested. Cells can be infected with multiple viruses as once. I'd be interested to know if it's the same viral variants which become dominant in all colonies affected by varroa or if the dominant strain(s) vary. Might read up if I get a chance.

 

[Erichalfbee]

Think most on here are aware of the feeding on fat tissue. He's questioning your assertion that that is the main issue with varroa rather than the viral vector effect being the major issue. It's likely a combination of both.

Must admit that the idea of virus variants out competing each other is a bit of an intriguing one depending on the mechanism being suggested. Cells can be infected with multiple viruses as once. I'd be interested to know if it's the same viral variants which become dominant in all colonies affected by varroa or if the dominant strain(s) vary. Might read up if I get a chance.

Variants A and B predominate depending on locality. It’s in The Proff’s work

 

[Boston Bees]

I don't really understand what the purpose of this argument is.

Varroa introducing viruses to bees while in their cells = very bad for their health
Varroa feeding off fat body of "adult" bees = also very bad for their health

 

[pargyle]

Variants A and B predominate depending on locality. It’s in The Proff’s work

Wasn't it the B Variant that was found to predominate in Ron Hoskins bees ... and they appeared not to suffer with the more serious effects of the A variant ?

 

[Mdurigan]

Mate, sorry for your losses!
When that happens is tough to take in.
Down here in Brazil is common to lose them to crop spraying if your hives are close to some plantations (soya and corn). From the pic it looked there are loads of deadline bees at the botton which here are clear signs of poisoning.

 

[jenkinsbrynmair]

Wasn't it the B Variant that was found to predominate in Ron Hoskins bees ... and they appeared not to suffer with the more serious effects of the A variant ?

Yes - nothing to do with 'hygienic' behaviour. Although I think further research by Steve Martin has found that maybe the B variant is not quite as benign as we thought.
Still a lot of work to do with this I think, although it's interesting to find that the B variant is endemic in the Southern hemisphere, especially in Africa and the bees there seem to coexist with varroa with little interference from us.
We got an unexpected bonus during the Spring Convention one year when Jurgen Tautz had to cancel due to illness and Prof. Martin stepped in last minute, many almost didn't bother going to the lecture but it was one of the best I've ever attended, it was there that this type A/B findings were first unveiled.

 

[Angry_Mob]

So do you lot use unvented goggles? All the ones I’ve seen are vented from what I’ve been able to find at Screwfix etc.

I use 3M safety googles: 3M Goggle Gear Safety Goggles, Scotchgard Anti-Fog, GG501SGAF-EU : Amazon.co.uk: DIY & Tools

Re a couple of earlier posts about the full face mask; they are terrible.

Better with the split mask IMO. The face masks always steamed up on me very quickly meaning I had to remove the whole mask frequently to wipe down the visor whereas if you go with the half mask and proper googles you can keep the mask on and remove the googles, give them a quick wipe and put them back on. The half-mask googles don't seem to steam up as quick either.

Also works out cheaper and is easier to store.

 

[Erichalfbee]

Yes - nothing to do with 'hygienic' behaviour. Although I think further research by Steve Martin has found that maybe the B variant is not quite as benign as we thought.
Still a lot of work to do with this I think, although it's interesting to find that the B variant is endemic in the Southern hemisphere, especially in Africa and the bees there seem to coexist with varroa with little interference from us.
We got an unexpected bonus during the Spring Convention one year when Jurgen Tautz had to cancel due to illness and Prof. Martin stepped in last minute, many almost didn't bother going to the lecture but it was one of the best I've ever attended, it was there that this type A/B findings were first unveiled.

Ah yes. I had forgotten about Stephen Martin’s work. Something else for beeginner to read? It was a good lecture