# General beekeeping > Bee health >  Dwv

## GRIZZLY

The news this morning has it that Dwarf Wing Virus is the world-wide silent killer of bees,spread by Varroa.There is no known treatment and infected hives would be located and dealt with ???.   :Confused:

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## Neils

Dealt with?

Nearly 30% of colonies inspected have DWV present From what I heard. Not seen that in writing mind

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## Bumble

The Mail carries an article about it, and, for a change, it looks as if they got the words right.

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## Jon

Guardian as well.

Usual selection of inane comments about Monsanto and Bayer below, many from gutted anti neonicotinoid campaigners!

One guy claims that it has been 'proven' that neonicotinoid pesticides cause CCD. He forgot to post his link to the proof though!

Mind you given the track record of Damian and Alison Benjamin in the Guardian it is hard to take their bee coverage seriously.

This study is very interesting as it does show the mechanism whereby the varroa mite enables a destructive virus to dominate over others and reach lethal levels.

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## Neils

And the BBC

I don't think it will make much difference to the anti-pesticide campaign. As one biologist opined about creationists "The problem with finding *The* Missing link is that it just means we have to find two more"

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## Jimbo

I had a quick read of the abstract which was published in the latest edition of Science. The bit I found amusing was the scientists did their research in Hawaii as they had to compare non varroa infected colonies with recent varroa infected colonies. If you were a scientist from Sheffield would you chose to go to Hawaii or the West Coast and Islands of Scotland where there are also varroa free colonies. What would you chose?
It also highlights to me these varroa free areas / native bee areas in Scotland should be protected as they are an important resource for scientists and future research and that the SBA should be in discussion with the Scottish goverment to put some legislation in place to protect the areas

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## Jon

To be fair Jimbo, the key factor was that Varroa only arrived in Hawaii 5 years ago and they studied 2 islands with bees with recently arrived mites and two others which were still mite free - so they had a perfect was to compare bee colonies recently exposed to mites with a very similar population never exposed to mites. They found that a particular strain of DWV seemed to replace most of the other viruses. But yes you cannot rule out the tanning factor entirely.

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## Neils

15 years longer exposure in the uk compared to Hawaii perhaps? You've got areas of Hawaii unpopulated by varroa and areas where the exposure is at most a couple of years old, I'd have thought that would make a much more useful comparison I terms of uninfected and newly infected rather than a general population of bees that have been kicking around with varroa and associated viruses for 20 years.

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## The Drone Ranger

Sadly it's as a result of scaremongering by beekeepers initially that started the press interest in bees.

Anyone who keeps chickens were dragged into a government led scaremongering madness a few years ago and had to make provision to bring all their birds indoors.
Oh no bird flu got boring lets write about bee Armageddon 
Least its not killer bees -- that went on for a few years

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## The Drone Ranger

> If you were a scientist from Sheffield would you chose to go to Hawaii or the West Coast and Islands of Scotland where there are also varroa free colonies. What would you chose?


I choose Hawaii  :Smile:

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## Jon

Some people like their mizzle.

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## The Drone Ranger

> Some people like their mizzle.


 what the heck is mizzle ??

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## Jon

What falls from the air and hangs in the sky and clings to your garments anywhere in the West of Scotland or indeed many parts of the island of Ireland.

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## lindsay s

> It also highlights to me these varroa free areas / native bee areas in Scotland should be protected as they are an important resource for scientists and future research and that the SBA should be in discussion with the Scottish goverment to put some legislation in place to protect the areas



Theres a serious debate taking place amongst the Orkney beekeepers at the moment about protecting our varroa free area. Legislation and education are seen as the way forward. Personally I think legislation will be a waste of time and effort. We all know what happened when varroa was first discovered in England back in 1992, lines were drawn on maps and statuary infected areas were declared. Legislation didnt stop the spread of varroa and once it jumped the Caledonian Canal the Scottish government gave up on it completely. While I believe Andrew Abrahams has had success with the status of his Colonsay bees, Orkney doesnt fit the same mould. Our Islands are spread out and with a population of 20,000 we have large numbers of people moving in and out the whole time.       
Educating potential beekeepers and those intending to bring bees to Orkney about our varroa free status has been successful so far, but it will just take one beekeeper who doesnt know or doesnt care and varroa will arrive here by the back door.
The weather here in the past week has been windy and cold, foggy and cold, rainy and cold or a combination of all three I would stick with Hawaii.

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## Stromnessbees

> The news this morning has it *that Dwarf Wing Virus is the world-wide silent killer of bees*,spread by Varroa.There is no known treatment and infected hives would be located and dealt with *???*.


Hi Grizzly

You are right to put a whole lot of questionmarks to this article.
The first time I saw DWV was more than 20 years ago in Austria, and it was never a problem worth worrying about, except that it indicated that varroa treatment was needed.

The fact that it is now hyped as the cause of the bee decline just shows that anything seems to be good enough at the moment to distract from the real reason of the worldwide bee problems, the systemic neonicotinoid pesticides.

Unfortunately not everybody here is prepared to question these media hypes, some people even seem to want to reinforce them:

Gavin for example has left his position as admin again to cut and paste the whole BBC article right on the front page of the forum!

Not only did he take it on without questioning the message, he even changed the more benign title of 
_
'Honeybee virus: Varroa mite spreads lethal disease'_ 

to the much more misleading 

_'Honeybee problems explained'. 


_I pointed this out in a comment to the article, but my comment was made invisible nearly immediately.  :Frown: 


How could it be, that the scores of scientists who investigated CCD and other bee problems should not have noticed huge amounts of bees with deformed wings?

How should bees with deformed wings have disappeared from their hives and left just an empty box behind, as they obviously can't fly?


We cannot allow misleading media hypes like these to distract from the real reasons of the bee problems any longer. The more of us object to this type of misreporting the better.

Maybe Gavin wants to explain what he had in mind when he posted this article so prominently?

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## Jon

Doris. Go and read the paper. You have completely misunderstood the point of it.
The main finding is that when varroa is introduced to a new area, it vectors a single one of the variants of DWV which comes to predominate - at the expense of the other variants. There are many variants of DWV and the one which the varroa mite facilitates happens to be the variant which causes the most damage to bees. This study documented how the virus population changed over a couple of years and how it differed between islands which have mites and islands which do not have mites.

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## Stromnessbees

> Doris. Go and read the paper. You have completely misunderstood the point of it.
> The main finding is that when varroa is introduced to a new area, it vectors a single one of the variants of DWV which comes to predominate - at the expense of the other variants. There are many variants of DWV and the one which the varroa mite facilitates happens to be the variant which causes the most damage to bees. This study documented how the virus population changed over a couple of years and how it differed between islands which have mites and islands which do not have mites.


I have read the article and understood fully what it is about. 

What I am pointing out is the misleading presentation of the article on the forum front page. 


Furthermore I agree with Jimbo who pointed out that this research could have easily been done in the UK, thereby saving a lot of money that could have been used to investigate the real bee problems.

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## prakel

> How should bees with deformed wings have disappeared from their hives and left just an empty box behind, as they obviously can't fly?


Just a quick thought, other than when I've taken the roof off I don't _think_ that I've ever seen a bee fly out of a hive.What I have seen are bees _walking to the exit_ and then flying from the hive.

EDIT: on 8th July 2012. 

I wrote, a month ago, "and then flying from the hive" to which, perhaps I should have added "...or continuing to walk from the hive because they can't fly.." perhaps my post was just too subtle?

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## mbc

[QUOTE=Stromnessbees;11464]

How could it be, that the scores of scientists who investigated CCD and other bee problems should not have noticed huge amounts of bees with deformed wings?

How should bees with deformed wings have disappeared from their hives and left just an empty box behind, as they obviously can't fly?


QUOTE]
The deformed wing's caused by the virus I believe are only the accute tip of the iceberg (the only bit beekeepers can easily diagnose)and most bees with dwv appear normal, I may be wrong and cant find a reference to back this up, but I believe most of the damage caused by dwv goes unseen.

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## Jon

> most bees with dwv appear normal


MBC. That is correct and it is mentioned in the paper if you have access to it as opposed to just the press cuttings or the abstract.




> Furthermore I agree with Jimbo who pointed out that this research could have easily been done in the UK, thereby saving a lot of money that could have been used to investigate the real bee problems.


So where in the uk  have you got the equivalent of the situation in Hawaii where you can compare populations of bees on 4 islands, two without varroa and two with varroa introduced at an exact known point in time so you can compare how the bee virus populations differ between the two populations and monitor the changes longitudinally. This was a unique chance to study the initial impact of varroa on bee viruses and the changes the mite induces.

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## gavin

> I pointed this out in a comment to the article, but my comment was made invisible nearly immediately.


That's a lie, plain and simple.  Your comment is still there, but your persistently unpleasant attitude and your determination to post your neonicotinoid campaigning has caused me to withdraw your permission to post any more comments on the Home page or in the Blogs.  For now you are still allowed to post here, but don't bank on keeping that ability.

This is an important piece of work which shows a change in DWV after the introduction of Varroa, not just the amount per bee and the frequency of infection but also the type(s) of DWV present. 

On the Hawaii vs Scotland angle there is work taking place on Scottish infested and non-infested colonies.  UK-based reasearchers saw the value in looking at such material and are making progress on it.  However they haven't yet published the results and so we'll have to wait to learn more.

I should have said 'non-infested colonies sources in Scotland'.  I don't know where the infested colonies came from.

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## Stromnessbees

> That's a lie, plain and simple.  Your comment is still there, ...


Gavin, don't accuse me of lying!

On the forum home page we get your posting 'Honebee problems explained' and below it in blue writing it says '3 comments' with a little symbol next to it. 

When I click on this, the article expands to its full size, and the term '3 comments' is still there but no comments become visible.

When I click on it again nothing changes.


Maybe you made these comments invisible to all forum members except for moderators?

But I am definitely not lying!

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## Stromnessbees

Not a lie.jpg
This is all I get.

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## gavin

Then in that case I apologise for using such a strong term when something milder would have been appropriate.  I hadn't realised this, but I had effectively made the comments disappear for you alone while you are logged in.  My intention had just been to stop you posting comments there.

The comments are visible to all forum members except yourself.  They are also visible to any guest who drops by, and you should be able to see them by logging out.

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## Stromnessbees

> The deformed wing's caused by the virus I believe are only the accute tip of the iceberg (the only bit beekeepers can easily diagnose)and most bees with dwv appear normal, I may be wrong and cant find a reference to back this up, but I believe most of the damage caused by dwv goes unseen.


So can you please elaborate and tell us what happens to the infected bees?

Do you think they just have a normal life, do you think they fly away and then their wings deform and they can't fly back or do you think they just drop dead in the hive?

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## gavin

DWV is known to shorten the life of individual workers and is linked to failures of colonies to survive the winter.

http://aem.asm.org/content/78/4/981.short

Any wing deformation takes place as the adult hatches from the pupa.  Once the wings dry they are essentially inert structures and just become worn as the bee ages.

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## Stromnessbees

> DWV is known to shorten the life of individual workers and is linked to failures of colonies to survive the winter.
> 
> http://aem.asm.org/content/78/4/981.short
> 
> Any wing deformation takes place as the adult hatches from the pupa.  Once the wings dry they are essentially inert structures and just become worn as the bee ages.


I know that, but I wondered what MBC thought of it.  :Roll Eyes (Sarcastic): 


From the abstract:



> Individual dead workers were collected daily and quantitatively analyzed for deformed wing virus ...


In CCD the workers all disappeared, so they couldn't be collected.

This doesn't look conclusive to me. 
Can I have a look at the whole article please?

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## mbc

> I know that, but I wondered what MBC thought of it.


It appears you needed educating on the point at seven minutes past six yesterday :
"

How could it be, that the scores of scientists who investigated CCD and other bee problems should not have noticed huge amounts of bees with deformed wings?

How should bees with deformed wings have disappeared from their hives and left just an empty box behind, as they obviously can't fly?"

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## The Drone Ranger

Guys there is a lot of provocative and unnecessarily harsh comments in this link surely we can disagree without losing perspective.
A bandwagon pulled by hobby horses is just that 
You see lots of them in beekeeping 
I daresay there are lots of people who begin with the conclusion and look for the facts to fit it.
But be honest with yourselves we have all done it at some time or another.

You catch more bees with sugar than vinegar as they say

(That analogy doesn't work if flies are the target species though)

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## Ruary

> The news this morning has it that Dwarf Wing Virus is the world-wide silent killer of bees,spread by Varroa.There is no known treatment and infected hives would be located and dealt with ???.


 I am sorry to be pedantic but I think DWF is actually *Deformed* Wing Virus. Just so that people don't go round thinking there is a new kid on the block which kills everything.

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## EmsE

Here comes the silly question.....When they say Varroa is a vector for DWV, does this mean that the mite carries the virus and transmits it into the bee when it pierces through the exoskeleton (excuse the spelling) or does it mean that the varroa weakens the bees immune system that results in them succumbing to the virus that may already be present in the colony. From what I've read, I interpret it to be the 1st but I may have got it wrong.

Sent from my BlackBerry 8520 using Tapatalk

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## gavin

No question is silly on SBAi (well, almost none).  The former, I believe.  Might be a touch of the latter too, but the former is the thing.

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## Jon

The virus is already in the bee population before any contact with varroa mites but something about the interaction between mites and bees changes the frequency of the viruses which are present in the population. There was some discussion re possible mechanisms in this Hawaii paper. The main finding of this paper is that when varroa mites are introduced to a bee population, one variant of DWV comes to predominate at the expense of all the other variants and unfortunately this variant of DWV is the one which causes most harm to the honeybee.

Edit
And to add to what Gavin just posted above, the speculation is that the virus get recycled between bee and mite by the haemolymph sucking action of the mite.

From the paper:




> Many factors are likely to influence the DWV
> variant population in different colonies, but the
> arrival of DWV variants that can replicate in the
> mite (13) means that these strains would rapidly
> increase in abundance. There have been no major
> introductions of honey bees into Hawaii, because
> strict importation regulations have been enacted
> since the widespread occurrence of Varroa mites.
> It seems likely that the now mite-associated
> ...

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## Bumble

I'm just wondering. An idle sort of thought, and I'm not sure if I can word it so I can ask what I want to ask, and I'm not sure if it's a dumb question.

The Hawaii study was of newly-infected bees. A brand new infection is likely to hit harder (I'm thinking of humans and measles). Is there any evidence that bees in areas that have had varroa ever since it arrived in UK (or elsewhere) are beginning to deal with this increased virulence?

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## Calum

the rule of thumb here is that when a colony is overloaded with varroa they will start showing DWV in noticable numbers.

cage the queen or best remove her and all open young brood & eggs.
 Also take of any supers you want to harvest. 
treat for varroa wait untill all the closed brood has hatched and treat again. destroy drone brood before it hatches as much more varroa will be in there. Requeen. done.

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## Jon

> Is there any evidence that bees in areas that have had varroa ever since it arrived in UK (or elsewhere) are beginning to deal with this increased virulence?


I think there is some evidence that bees can adapt.

The Primorsky strain of honey bee in East Asia has coexisted with varroa mites for about 150 years and this strain has developed considerable resistance. Some US breeders specialise in 'Russians'

I imagine that the bees which have least resistance to varroa and virus will be eliminated quite quickly from the population allowing hardier strains to coexist to some extent with the varroa mites.

There has been work done on strategies which help bees live with varroa such as grooming, uncapping affected pupae, and general hygienic behaviour. Prof Ratnieks is working on this at Sussex University. At an amateur level Ron Hoskins in Swindon is also looking at how some bees can damage varroa mites by biting their carapaces.

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## The Drone Ranger

Haven't read much about Ron Hoskins lately I presumed he hit a brick wall
Some carapace damage ascribed to bees damaging mites turns out to be a genetic flaw I hear
Good luck to the guys trying this breeding hope it takes less than 150 years
Would we all need to buy resistant / hygienic queens
I think breeding a drone with shorter development time might be easier 
Drone hatching time varies by a day or so either way according to David Cramp

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## Jon

> Drone hatching time varies by a day or so either way according to David Cramp


I am pretty sure it is the same for queens and workers as well.
brood nest temperature must play a big part.

I heard that criticism about the mark on the carapace being natural rather than due to biting but I think that was subsequently shown to be incorrect. Gav knows about this biting of the carapace business.

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## Neils

There's a particular pattern on the carapace that was originally ascribed to biting that certainly at the IBRA conference was still very much considered a "birth defect" having seen some of Ron's samples first hand they are definitely not of the same type.

The defect are the two symmetrical dimples on the top of the carapace which apparently correspond to two large muscles underneath. In some mites as I understood it these muscles don't fully develop and the carapace dimples as a result.

Writing this on a bus so happy to be corrected if I've misremembered or just got it wrong

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## Neils

Aha, found an image posted by someone or other discussing this elsewhere  :Smile:

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## Bumble

> I think there is some evidence that bees can adapt.
> 
> The Primorsky strain of honey bee in East Asia has coexisted with varroa mites for about 150 years and this strain has developed considerable resistance. Some US breeders specialise in 'Russians'
> 
> I imagine that the bees which have least resistance to varroa and virus will be eliminated quite quickly from the population allowing hardier strains to coexist to some extent with the varroa mites.
> 
> There has been work done on strategies which help bees live with varroa such as grooming, uncapping affected pupae, and general hygienic behaviour. Prof Ratnieks is working on this at Sussex University. At an amateur level Ron Hoskins in Swindon is also looking at how some bees can damage varroa mites by biting their carapaces.


Prof Ratnieks uses liquid nitrogen to kill a patch of brood, then sees how quickly and efficiently the bees deal with it, I think Ron Hoskins has been trying to breed bees that will groom off varroa. In my mind these are physical traits or characteristics that might be useful, same as the dented varroa that might be less good at clinging onto bees.

I was wondering more about an innate immunity to strains of DVW that might have built up over generations, which is why I mentioned measles and humans. I wondered if there might be a genetic marker of some sort.

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## The Drone Ranger

There was a study done on breeding foulbrood resistant bees
They found that bees who removed infected larva early were able to survive longer
Bees who did nothing less so
Bees who removed larva late when loaded with infection were most likely to collapse

I'm sure they factor that in to the recent study.
I have seen it suggested that killing a patch of brood and seeing if bees remove them is something we all might try.
I suspect it would not tell us as much as we think.
Dead is one thing, infected another, and parasitism something else

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## Calum

> I have seen it suggested that killing a patch of brood and seeing if bees remove them is something we all might try.


 Yup here in Germany thats a catergory you can check for queen selection.

So a friend of mine has some nucs we made up together with DWV. We could treat with AS - which I am loathe to do as it will not do the open brood any good, and as the queens are very young carries an increased risk of doing them in. Any suggestions -Apivar / Apilife treatmens less agressive on the bees?

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## Stromnessbees

I recently received a request by *Reg Godwin and Glyn Davies* for queens from varroa free colonies. They would be used in a new study that examines the link between DWV and queen failures. 

I replied that I would be happy to support the research as long as the collected data would also be checked for a possible bias from neonicotinoid pesticides, as they are also a strong contender for affecting queen performance. 

According to Reg no question about possible exposure to these pesticides was included in the record sheets yet, and he would pass on my concerns.

I have not had a definitive answer about the final set of records yet, but I suspect that this study will be conducted without checking for a bias from neonics.

In my experience, any scientific study has to inlcude data that could produce a strong bias, or else the results cannot be relied upon. 

Likewise, one could conduct a study to see if, for example, eating chicken promotes lung cancer: if it isn't recorded whether the participants are smokers or not, the study becomes worthless.

I recommend that anybody else who is asked to supply queens for this study should request that neonic data be included in order to make sure there is no more money wasted on incomplete research.

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## Calum

Hi
nope thats wrong, as long as all test groups are subjected to the bais in equal terms/levels it can be ignored. Bais imples that one group is subjected to influences that another group have not been subjected to and that this effect has not been recorded/controlled. (although where effects are compounded this could become an issue -but then the number of factors by bees becomes unreal).
I'd start by asking for queens that are sisters from the same graft and mating area to start with....



> Likewise, one could conduct a study to see if, for example, eating chicken promotes lung cancer: if it isn't recorded whether the participants are smokers or not, the study becomes worthless.


 But they all breath air. Was it GM chicken?

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## Jon

> I replied that I would be happy to support the research as long as the collected data would also be checked for a possible bias from neonicotinoid pesticides, as they are also a strong contender for affecting queen performance.


Really. The only person I have heard state that is Graham White and latterly yourself quoting him.
His evidence was based on the fact that some of the new mated queens from his ten colonies were superseded early.
I wonder how he eliminated possible nosema from his conclusions as nosema has been associated with early supersedure for decades.
I remember him posting about it on the old bbka forum.
Roger Patterson highlights queen mating problems but he has always been careful to keep an open mind re. the causes as I have discussed it with him many times.

My thought for the day is that neonicotinoids are a strong contender for inducing climate change as it has rained all day and I got wet earlier.
Some may say that a low pressure area is over the UK and Ireland, but in the interest of avoiding bias I think we can't yet rule out Clothianidin for making my socks wet.

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## Adam

My assumption is that early queen failure - or queens that just stop laying but remain in the hive - is caused by Nosema and not a varroa vectored thing. In my case, as I haven't seen any dysentry, then N. ceranae is suspected. Last Autumn I treated with Fumidil B and Hivemakers thymol emulsion as a treatment for Nosema and this year I have not had any early failures. Not proof enough I know.

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## Adam

> I recently received a request by *Reg Godwin and Glyn Davies* for queens from varroa free colonies. They would be used in a new study that examines the link between DWV and queen failures. 
> 
> I replied that I would be happy to support the research as long as the collected data would also be checked for a possible bias from neonicotinoid pesticides, as they are also a strong contender for affecting queen performance. 
> 
> According to Reg no question about possible exposure to these pesticides was included in the record sheets yet, and he would pass on my concerns.
> 
> I have not had a definitive answer about the final set of records yet, but I suspect that this study will be conducted without checking for a bias from neonics.
> 
> In my experience, any scientific study has to inlcude data that could produce a strong bias, or else the results cannot be relied upon. 
> ...


Doris, you are in the fortunate position of not having varroa unlike (most of) the rest of us. Would you refuse to supply if there was no 'neonic bias' adjustment as you wish?

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## Stromnessbees

> Doris, you are in the fortunate position of not having varroa unlike (most of) the rest of us. Would you refuse to supply if there was no 'neonic bias' adjustment as you wish?


I would, yes.

It's just good practise to include questions about general colony health (e.g. signs for Nosema etc.) in the data sheet for every queen examined. The proximity to neonic treated crops nowadays has to be one of them, as it could significantly influence the results.

This doesn't need to make the study more expensive, as I say, it's just another question on the sheet. 

If it's not included then this might be an indication that the researchers don't want to find a connection even if there is one.

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## Jon

> If it's not included then this might be an indication that the researchers don't want to find a connection even if there is one.


Keep racking up those conspiracies. We just love 'em.

Just left 18 jars of honey down to the health food shop and got my socks wet again.

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## The Drone Ranger

in 2005 I had lots of drone laying queens later in the season 

But that might have been because I stocked half my hives with queens produced from my best hive.
Yep the nice tempered one who brought in all the honey in 2004  :Smile: 

I have 4 apideas and 6 of the horrible white things Kielers? 
I don't use them no more they stays in the shed a moulderin  :Smile: 

That was also the year when I got stung first on the nose then on the lip when collecting a swarm from a long ladder high up a tree (the ladder also stays in the shed now)

Quite a few other people had trouble that year with queens as I remember so it might have been due to other factors as well

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## Trog

There might be a problem with your proposal, Doris, in that the majority of varroa-free areas tend to be free of large agribusinesses too, therefore the bees in those areas are less likely to be exposed to neonics, etc.

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## gavin

> I recommend that anybody else who is asked to supply queens for this study should request that neonic data be included in order to make sure there is no more money wasted on incomplete research.


In that case what is your view of the corollary - studies that purport to investigate the effects of neonics that do it by means of surveys and which do not properly account for all the other variables?  This is particularly important for surveys which use geographical information to correlate colony losses with exposure to arable farming and neonics.  In this case the other variables that could affect colony loss data might also be correlated with geography.  Here are some that may affect colony losses:

- weather, such as rainfall patterns in the preceding year in the main honey gathering and queen mating seasons

- presence or absence of Varroa and the single type of DWV it amplifies

- local pockets of poor advice on controlling Varroa (powdered sugar, anyone?)

- general standards of beekeeping locally, including bee management and supplementary feeding when required

- diversity of forage and length of season of availability of forage

If inferences are being made on possible effects of exposure to neonics (those chemicals with a half-life in a bee of around 5 hours) based solely on survey data and geography, then is *anyone* justified in making statements on possible effects without considering these other, at least equally likely, geographically variable variables that could better explain colony losses?

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## Jon

That was the problem with the Harvard study.
It assumed before the experiment started that Imidacloprid was behind ccd and it ignored half a dozen other variables which would have influenced the results, varroa and nosema levels to name but two.

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## Stromnessbees

> In that case what is your view of the corollary - studies that purport to investigate the effects of neonics that do it by means of surveys and which do not properly account for all the other variables?  This is particularly important for surveys which use geographical information to correlate colony losses with exposure to arable farming and neonics.  In this case the other variables that could affect colony loss data might also be correlated with geography.  Here are some that may affect colony losses:
> 
> - weather, such as rainfall patterns in the preceding year in the main honey gathering and queen mating seasons
> 
> - presence or absence of Varroa and the single type of DWV it amplifies
> 
> - local pockets of poor advice on controlling Varroa (powdered sugar, anyone?)
> 
> - general standards of beekeeping locally, including bee management and supplementary feeding when required
> ...


A good study will take note of these variables and make allowances for them in the interpretation of the data. 
This is what makes biologial research so complex, especially when done outside a lab, where you can't exclude/control those influences. 

All I am saying is that proximity to neonic treated crops should be included as well.





> If inferences are being made on possible effects of exposure to neonics (those chemicals with *a half-life in a bee of around 5 hours*) based solely on survey data and geography, then is *anyone* justified in making statements on possible effects without considering these other, at least equally likely, geographically variable variables that could better explain colony losses?


Gavin, you have made misleading statements with regards to the duration of the effects of neonics on bees before, let's not go there just now.

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## Jon

> Gavin, you have made misleading statements with regards to the duration of the effects of neonics on bees before, let's not go there just now.


Well Suchail, who you were quoting the other week, seems to be what Gavin is quoting re 5 hours.
Maybe you are thinking of the persistence in soil which is much longer.

Page 7
http://www.gesundebiene.at/wp-conten...de-in-bees.pdf




> The low residue levels in honey bees probably are best 
> explained from the fast imidacloprid metabolism by the
> honey bee A. mellifera. After exposure to sugar water dosed
> at 20, 50 or 100 lg 14C-imidacloprid kg-1 honey bee, halflives
> were 4–5 h (Suchail et al. 2004a, b). The major
> metabolites are 4- and 5-hydroxy-imidacloprid and olefin.
> Olefin peaked after about 4 h, while the hydroxy metabolite(
> s) appeared either immediately after termination of
> exposure and then decreased in concentration (Suchail
> ...

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## gavin

I seem to have (helped) derail this thread into neonics again.  Can we keep it for Deformed Wing Virus please?

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## The Drone Ranger

> I seem to have (helped) derail this thread into neonics again.  Can we keep it for Deformed Wing Virus please?


 sorry I was off piste there  :Smile: 
Fair enough it is Saturday after all

"Where am I nurse ??"

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## Stromnessbees

> I seem to have (helped) derail this thread into neonics again.  Can we keep it for Deformed Wing Virus please?


Ok.

So can you please explain how DWV, which has been observed at least since we have had varroa, is supposed to have suddenly caused CCD, and why this didn't occur before the widespread use of neonicotinoids?





> A colony which has collapsed from CCD is generally characterized by all of these conditions occurring simultaneously:[34]
> 
> Presence of capped brood in abandoned colonies. Bees normally will not abandon a hive until the capped brood have all hatched.Presence of food stores, both honey and bee pollen:
> i. which are not immediately robbed by other beesii. which when attacked by hive pests such as wax moth and small hive beetle, the attack is noticeably delayed.Presence of the queen bee. If the queen is not present, the hive died because it was queenless, which is not considered CCD.
>  Precursor symptoms that may arise before the final colony collapse are:
> 
> Insufficient workforce to maintain the brood that is presentWorkforce seems to be made up of young adult beesThe colony members are reluctant to consume provided feed, such as sugar syrup and protein supplement.


(Wikipedia)

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## Jon

> Ok.
> 
> So can you please explain how DWV, which has been observed at least since we have had varroa, is supposed to have suddenly caused CCD, and why this didn't occur before the widespread use of neonicotinoids?


You need to read to paper to see how the arrival of varroa promotes the single most virulent strain of DWV at the expense of other strains of DWV which are less harmful to bees.
CCD cases in the US occured more than ten years after the widespread use of neonicotinoids in the US. No correlation there at all.




> (Wikipedia)


Wow!

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## Stromnessbees

> You need to read to paper to see how the arrival of varroa promotes the single most virulent strain of DWV at the expense of other strains of DWV which are less harmful to bees.
> 
> CCD cases in the US occured more than ten years after the widespread use of neonicotinoids in the US. No correlation there at all.


The correlation is actually very good:

In the 1990s Imidacloprid was introduced, and we didn't hear much about adverse effects. 
But around 2004 Imidacloprid was replaced by Clothianidin, which is three times as toxic to bees as Imidacloprid. 
I assume that this triple toxicity was not taken into account when it was introduced and the bees were hit hard by this new type of neonicotinoids, resulting in massive occurrences of CCD, which is exactly what is to be expected from the way this neurotoxin works.

When the pesticide companies realized that they had done an 'overkill' they reduced the Cothianidin concentrations on the seed coatings again, so outright CCD is not observed as often anymore, but bee colonies in proximity of treated fields suffer reduced vitality, become susceptible to secondary infections and are likely to have queen problems.

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## Jon

> When the pesticide companies realized that they had done an 'overkill' they reduced the Cothianidin concentrations on the seed coatings again, so outright CCD is not observed as often anymore,


Really? Is that another very silly conspiracy theory or have you a reference for that?
Sorry for asking for evidence again but it is how I sort out the truth from the dross re. the content of internet forums.




> I assume that this triple toxicity was not taken into account


Why do you assume that. Again you would need to provide just a wee bit of evidence for that claim.
Was the testing regime suspended for a few years?

Glad you see your tacit acknowledgement that Imidacloprid has nothing to do with CCD.
You should have a word with Dr Lu at Harvard as his is still labouring under that misapprehension.

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## Stromnessbees

> Really? Is that another very silly conspiracy theory or have you a reference for that?
> Sorry for asking for evidence again but it is how I sort out the truth from the dross re. the content of internet forums.
> 
> 
> Why do you assume that. Again you would need to provide just a wee bit of evidence for that claim.
> Was the testing regime suspended for a few years?
> 
> Glad you see your tacit acknowledgement that Imidacloprid has nothing to do with CCD.
> You should have a word with Dr Lu at Harvard as his is still labouring under that misapprehension.


Let's stay on the DWV topic: 

I will answer your question as soon as anybody on this forum can explain to me how DWV can cause the symptoms of CCD and why it didn't do so before the introduction of Clothianidin.

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## drumgerry

Jon - you should know better by now than to ask a direct question and expect a direct answer!

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## fatshark

> I will answer your question as soon as anybody on this forum can explain to me how DWV can cause the symptoms of CCD ...


I'm not aware of any study that demonstrates that DWV does cause the symptoms of CCD.  Most of us working in the Varroa-rich mainland have plenty of DWV (virus that is, not necessarily deformed wing disease) as will/has been shown in the random apiary survey by the NBU.  However CCD - at least as defined and accepted from the USA description - does not occur here.

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