Varroa aggregate on young drones, IN PREFERENCE to nurse bees

[TomH]

Drone brood removal seems to have questionable at best results in terms of an effective mite control.

We should move away from the individual 'caste' way of thinking, and treat the colony as one super organism. Messing with any of the individual 'organs' is going to have a detrimental effect on the colony as a whole. As well as mating, drones play an important role in colony thermoregulation, so not entirely the useless sex machines they are often labelled as.

Just wait until the BBKA annual winter loss survey comes out, with accompanying complaints of poorly mated queens... I wonder why, if you do insist on forking out drone brood every couple of weeks....

 

[BaconWizard]

Drone brood removal seems to have questionable at best results in terms of an effective mite control.

What does any of that have to do with this thread?

 

[Michael Palmer]

To me, the important part is how many bees one mite can bite and infect. Mites don't ride around on a young bee for a few days before they enter another brood cell. Rather, they move around from bee to bee, infecting many bees.

 

[Erichalfbee]

Not sure why this has been moved to treatment-free. The video needs to be seen by everyone and I am not suggesting going without treatment, in fact my OP specifically mentions treating them.

OK moved back

 

[BaconWizard]

OK moved back

Thank you.

 

[MillMeadow]

@MillMeadow
Is this the one you are refering-to? That would be drone BROOD not adults, ie the conventional method we all know about already.

No, I think it was in resposne to a question he was asked in a live chat either on his Patreon or as part of a Q&A as a guest. Could have been related to a query about a dedicated drone cage ( not brood trapping )

I don't need much of an excuse to listen to NHC back catalogue so I'll have a listen* back through them and keep an ear out for it

 

[BaconWizard]

No, I think it was in resposne to a question he was asked in a live chat either on his Patreon or as part of a Q&A as a guest. Could have been related to a query about a dedicated drone cage ( not brood trapping )

I don't need much of an excuse to listen to NHC back catalogue so I'll have a listed back through them and keep an ear out for it

Nor I! I'd be super interested to see it.

 

[Erichalfbee]

It seems to me that a potential treatment that could come out of this (rather than better detection methods) might be to insert drone-comb, trap it in a queen-cage once filled with eggs/drone-brood and then either kill or treat the trapped drones during the 4 days following emergence. Especially in May, June and July.

Sorry...I haven't managed to watch all of this. Does the research show that other mites are attracted to the drones wandering around the frame?

 

[jenkinsbrynmair]

and what about the other drones wandering around the hive?
And what do you do with the mite riddled drones?
And how can drones mate with a queen if they are trapped in a cage?

 

[Erichalfbee]

We already know that varroa mites do not parasitise larvae as soon as they emerge. So maybe they ride around more on drones. I'd be interested to know how he counted the mites on the bees he sampled and put back in the colony. Mites are not easy to find as they feed between the tergites and remain hidden. Maybe he just spotted the mites hitching a lift on the thorax?

 

[BaconWizard]

Sorry...I haven't managed to watch all of this. Does the research show that other mites are attracted to the drones wandering around the frame?

A few things are revealed. One is that yes, mites are not only attracted to drone brood as we already know but that phoritec mites vastly prefer and are attracted to

1) young adult bees under the age of 4-5 days rather than say 1 week old
2) much prefer young adult drones to young nurse bees. (also under 4-5 days old) I will need to re-watch to remember how much they prefer drones. I think it was 2/3 mites in the colony are found on drones if they are present. I need to check.

Mites do NOT hatch in drone brood and then hop immediately onto nurse bees, but instead the drones hatch and a large proportion of mites from elsewhere in the colony, converge upon the young drones.

It also shows that mites hop from host to host rather than staying on just one until it's time to breed and that this is another vector for DWV etc; an uninfected mite can parastise an infected bee, and transfer that virus to a new uninfected bee.

It also points out that while the mites are on drone hosts, the spread of viruses is slowed for a veriety of reasons including that trophalixis is only one-way with drones. And that alcohol washes despite being the most accurate method used currently, don't show the true count because they are done on nurse-bees.

Finally that the mites migrate en-masse to nurse bees when drones are no longer being produced or welcomed in times of dearth or late in the season.
So that you get a very sudden percieved spike of infection and a massive sudden change in the transmission of viruses through mites as the vector at the same time. In fact, the mites were there all along but on drones, undetected. Leading to the situation where you can have a colony that seems to be absolutely booming and then collapses suddenly or fails in winter/spring.

---

Not part of the research but being suggested by me rather exitedly, is the potential not only to improve detection but to use this information as part of a treatment regime. Perhaps trap and destroy or specifically treat young ADULT drones rather than capped drone brood. Perhaps develop a sticky mite-trap based upon drone pheromones... all very speculative of course.

 

[Erichalfbee]

A few things are revealed. One is that yes, mites are not only attracted to drone brood as we already know but that phoritec mites vastly prefer and are attracted to

1) young adult bees under the age of 4-5 days rather than say 1 week old
2) much prefer young adult drones to young nurse bees. (also under 4-5 days old) I will need to re-watch to remember how much they prefer drones. I think it was 2/3 mites in the colony are found on drones if they are present. I need to check.

Mites do NOT hatch in drone brood and then hop immediately onto nurse bees, but instead the drones hatch and a large proportion of mites from elsewhere in the colony, converge upon the young drones.

It also shows that mites hop from host to host rather than staying on just one until it's time to breed and that this is another vector for DWV etc; an uninfected mite can parastise an infected bee, and transfer that virus to a new uninfected bee.

It also points out that while the mites are on drone hosts, the spread of viruses is slowed for a veriety of reasons including that trophalixis is only one-way with drones. And that alcohol washes despite being the most accurate method used currently, don't show the true count because they are done on nurse-bees.

Finally that the mites migrate en-masse to nurse bees when drones are no longer being produced or welcomed in times of dearth or late in the season.
So that you get a very sudden percieved spike of infection and a massive sudden change in the transmission of viruses through mites as the vector at the same time. In fact, the mites were there all along but on drones, undetected. Leading to the situation where you can have a colony that seems to be absolutely booming and then collapses suddenly or fails in winter/spring.

---

Not part of the research but being suggested by me rather exitedly, is the potential not only to improve detection but to use this information as part of a treatment regime. Perhaps trap and destroy or specifically treat young ADULT drones rather than capped drone brood. Perhaps develop a sticky mite-trap based upon drone pheromones... all very speculative of course.

Thanks. I finally got round to watching it

 

[pargyle]

and what about the other drones wandering around the hive?
And what do you do with the mite riddled drones?
And how can drones mate with a queen if they are trapped in a cage?

YES ... There's a lot of questions that need to be answered ... I've only been able to look at a small part of the video so far (50 mins not spare at the moment) but the study seems to suggest that varroa are disproportionately attracted to young drones. If this is the case then it does present opportunities for those who don't want any chemicals or other treatments introduced into their colonies - but - it would have to be something that did not kill the drones as far as I'm concerned as I think the drones are an important and largely understood component of the hive organism.

I suppose the obvious, non-lethal, method would be to trap the emerging drones (quite easy of you inserted a cage made of queen excluder on any frames of drone brood), once the drones emerge you could remove the frames, put them in a separate box and give them a dose of OA by sublimation to kill the mites or cover them in icing sugar to get the mites to drop off.

Would it be a bit of a faff ? Probably yes ... but there are some people who are keen to remain largely treatment free and put up with a bit of a faff in order to maintain chemical free colonies.

 

[Erichalfbee]

Another thing....
Why wait for a trapped drone brood frame to emerge before killing the drones...and their mites?
Why not kill the brood in the first place?

 

[BaconWizard]

We already know that varroa mites do not parasitise larvae as soon as they emerge. So maybe they ride around more on drones. I'd be interested to know how he counted the mites on the bees he sampled and put back in the colony. Mites are not easy to find as they feed between the tergites and remain hidden. Maybe he just spotted the mites hitching a lift on the thorax?

He did an alcohol as a control, and then on the same occasion did a count by hand (one by one!) of the same sample-size of bees to check that their hand-counting and the alcohol wash corrolate. At the time, he also trapped and hand counted mites feeding on drones. This was done 9 days consecutively over a number (?) of colonies in May, June, July (and I think august?) and this was repeated over 2 years.

Each time he did this, the hand-counted bees were not killed as is the case by alchohol wash and were marked with colours to indicate its age and if carrying mites, so that they could be tracked and re-counted through the study and new markings applied if applicable.

 

[pargyle]

Another thing....
Why wait for a trapped drone brood frame to emerge before killing the drones...and their mites?
Why not kill the brood in the first place?

LIke I said above ... Bees produce drones because they want drones .. killing them is counter productive.

 

[BaconWizard]

YES ... There's a lot of questions that need to be answered ... I've only been able to look at a small part of the video so far (50 mins not spare at the moment) but the study seems to suggest that varroa are disproportionately attracted to young drones. If this is the case then it does present opportunities for those who don't want any chemicals or other treatments introduced into their colonies - but - it would have to be something that did not kill the drones as far as I'm concerned as I think the drones are an important and largely understood component of the hive organism.

I suppose the obvious, non-lethal, method would be to trap the emerging drones (quite easy of you inserted a cage made of queen excluder on any frames of drone brood), once the drones emerge you could remove the frames, put them in a separate box and give them a dose of OA by sublimation to kill the mites or cover them in icing sugar to get the mites to drop off.

Would it be a bit of a faff ? Probably yes ... but there are some people who are keen to remain largely treatment free and put up with a bit of a faff in order to remain chemical free colonies.

100% this. It is something I would like to try but nothing I do could give scientific data, just anecdote.
Chemically treat the drones after 3 days and release them. I would suggest that sticking them seperately into a nuc with some nurse bees and food would enable either OA vape or 3 days of formic acid and might be fairly practical.

Unfortunately, drones are pretty fragile and it seems are highly susceptible to damage from various chemicals including organic treatments, making them infertile (I don't have THOSE studies to-hand to cite at the moment) so this might be almost as bad as euthenizing them.

 

[BaconWizard]

Another thing....
Why wait for a trapped drone brood frame to emerge before killing the drones...and their mites?
Why not kill the brood in the first place?

Because mites are attracted to young ADULT drones. FROM nurse bees/ elsewhere in the colony.

 

[pargyle]

100% this. It is something I would like to try but nothing I do could give scientific data, just anecdote.
Chemically treat the drones after 3 days and release them. I would suggest that sticking them seperately into a nuc with some nurse bees and food would enable either OA vape or 3 days of formic acid and might be fairly practical.

Unfortunately, drones are pretty fragile and it seems are highly susceptible to damage from various chemicals including organic treatments, making them infertile (I don't have THOSE studies to-hand to cite at the moment) so this might be almost as bad as euthenizing them.

Three or four days of bashing them daily with icing sugar over a mesh floor with a sticky board underneath ? But they would have to be kept locked in or they would be flying off somewhere ... Like I said, it's a bit of a faff ...

 

[rolande]

I suppose the obvious, non-lethal, method would be to trap the emerging drones (quite easy of you inserted a cage made of queen excluder on any frames of drone brood), once the drones emerge you could remove the frames, put them in a separate box and give them a dose of OA by sublimation to kill the mites

With their reputation for suffering stress I doubt the drones would be much use afterwards.