Would you treat?

[pargyle]

I did a count today before I took the Thymol treatment off. 1 mite only, so the total Varroa count for the treatment was 125.

Not sure what all this proves. I had a low drop count before the treatment and was persuaded by comments on this forum that even if you don't see them or count them, they are still there and should be treated. With hindsight, I should perhaps have had the courage of my original convictions and left them alone. We live and learn!

Thanks for your link, Heidi, to the song clip. Nicely decorated hives in the background! Where have I seen those before?

One of the things I will be doing, in future, when doing Varroa monitoring using a sticky board below the OMF is to check whether the bees are doing any damage to the mites that drop - are the bees going after the mites aggressively and cleaning out the Varroa? There are beekeepers down here who are trying to breed that characteristic into their colonies - see http://www.jameskilty.co.uk/beekeeping/improvement.htm For the bees to develop this behaviour, there has to be some mites in there for them to practise on!

CVB

Well ... At least there are 125 dead ones which is 125 less for your bees to cope with. I'm not treating ... I can't find any signs of mites in the hive no matter what I do ... I even resorted to watching upside down bees on my new polycarbonate crown boards ... not a sign of any varroa. There's no earwigs in the bottom tray ... and I've looked at all hours of the day and night ... So, I'm probably dillusional but I think it's worth giving the bees a chance without bashing them with thymol or anything else for that matter. We'll see next spring ....

 

[TryingToLetThemBee]

I finally saw a mite on the board a couple of weeks ago. Put on Apiguard two days ago and a few mites are dropping, so v much in line with CVB's experience. As someone wise on here said, it's a balancing act and the thymol certainly stresses the bees so my inclination if I get similar numbers is to take it off. The problem with THAT is that, with a 125-mite kill, unless you know you are seeing more than 1-in-8 on your board, then you might still have 1000 mites. Nightmare. Mitemare, even.

 

[charlievictorbravo]

Conclusions of my Autumn Thymol Treatment

Followers of this thread will know I've just finished, prematurely, my Hivemaker's Thymol treatment. A summary of the mite drop has attached to this post.

As TTLTB has said, deciding whether to treat is a balancing act and if I'd known then what I know now about my infestation, I would not have treated. If you want some confidence as to the level of your hive's mite load, you might need to change your monitoring system - try this, but you do lose 300 bees - http://scientificbeekeeping.com/sick-bees-part-11-mite-monitoring-methods/

My plans for next year include buying some Varroa-killing queens from Rodger Dewhurst - see link in my post yesterday - to see if I can get away without chemical interventions. There's a thread on here today about bees biting their keepers and if we give the bees the opportunity to bite Varroa and thereby keep the infestation well below critical levels, we may be able to breed into our bees an element of Varroa tolerance/grooming - that's the ultimate goal, isn't it. But to develop that characteristic they need Varroa to practise on! A hive made clean by 6 weeks of chemical treatment may not be the best thing for bees in the long run.

CVB

 

[user 6228]

... There's a thread on here today about bees biting their keepers and if we give the bees the opportunity to bite Varroa and thereby keep the infestation well below critical levels, we may be able to breed into our bees an element of Varroa tolerance/grooming - that's the ultimate goal, isn't it. But to develop that characteristic they need Varroa to practise on! A hive made clean by 6 weeks of chemical treatment may not be the best thing for bees in the long run.

CVB

and perhaps we also need to breed a strain of varroa that reproduces slowly enough that the biting bees can control sufficiently...

 

[charlievictorbravo]

What's happening - Why so many Varroa?

As you will see above, I did HM's Thymol treatment in September but stopped part-way through the second phase because I was getting very low drops of Varroa and there was no brood that I could see and very little stores - my thoughts were that a few mites would not kill them but no stores and no brood certainly would. Since then I've been feeding during cool weather and letting them get on with it when they're foraging on Michaelmas Daisies and Ivy.

I put the monitoring board in two days ago and when I checked an hour ago I had 12 mites (all, as far as I could see, dead) on the board. The Beebase Varroa calculator suggests this is indicative of between 300 and 1200 mites in the colony.

What's going on? Where did they all come from and what's the best thing to do with such an infestation. It looks like they're in line for an Oxalic Treatment, which I was hoping to avoid, at Christmas but would they suffer if I did an icing sugar treatment now, while it's still relatively warm?

Thanks for any insights.

CVB

 

[jenkinsbrynmair]

would they suffer if I did an icing sugar treatment now, while it's still relatively warm?
CVB

Wouldn't do any harm - to the mites
Should have carried on with the thymol treatment - always found more of a mite drop at the end than the beginning.

 

[drstitson]

"my thoughts were that a few mites would not kill them but no stores and no brood certainly would. "

no brood = no brood rearing = no ageing of nurse bees
so you don't make new winter bees but aren't losing existing potential ones!

the remaining foragers will forage whether or not you are treating.

 

[alanf]

I put the monitoring board in two days ago and when I checked an hour ago I had 12 mites (all, as far as I could see, dead) on the board. The Beebase Varroa calculator suggests this is indicative of between 300 and 1200 mites in the colony.

I had a colony with low drop rates though a summer a couple of years ago. Thymol treatment into October dropped hundreds, I think earlier monitoring was affected by being near an ant colony, they were taking dead mites from the sample sheet. Just one of the reasons for variations in observed drops that means it's not a measure you can always rely on, although it is easiest.

The NBU calculator also says that short samples can be inaccurate. It recommends 7 days as a basic figure. However, statistically, if you get consistent drop rates over several short periods that's more reliable than any single longer sample period. I'd try again for two or three days, if you get 6 per day again that's likely to be a realistic drop rate.

If the drop rate confirms that you have, say, 500 mites now and the colony keeps breeding for the next two months, that's 2000 by mid December. Plus a high proportion of the bees that you are relying on going into Spring will have mite damage. That's not good. If you have hundreds of mites in a colony in mid October, they need treating ASAP. Whatever your inclinations, I'd be looking at the chemical miticides or depending on how much brood they have now, oxalic.

 

[oliver90owner]

They could have arrived from a collapsing colony which was robbed out by your bees, or the bees from the failing colony joined yours. There may be other reasons, but that is one possibility (or is that two?).

 

[itma]

As you will see above, I did HM's Thymol treatment in September but stopped part-way through the second phase because I was getting very low drops of Varroa and there was no brood that I could see and very little stores - my thoughts were that a few mites would not kill them but no stores and no brood certainly would. Since then I've been feeding during cool weather and letting them get on with it when they're foraging on Michaelmas Daisies and Ivy.

I put the monitoring board in two days ago and when I checked an hour ago I had 12 mites (all, as far as I could see, dead) on the board. The Beebase Varroa calculator suggests this is indicative of between 300 and 1200 mites in the colony.

What's going on? Where did they all come from and what's the best thing to do with such an infestation. It looks like they're in line for an Oxalic Treatment, which I was hoping to avoid, at Christmas but would they suffer if I did an icing sugar treatment now, while it's still relatively warm?

Thanks for any insights.

CVB

If you have no brood, you can treat with Oxalic.
Christmas is when most expect least chance of there being brood, but that's not guaranteed.
There's no particular need to wait until Christmas, other than that's when people are hoping that their colony should be broodless. LASI (at Sussex Uni) cull the brood deliberately before Oxalic treatment ... (Oxalic doesn't touch mites in sealed brood cells - where the mites will be, given any brood.)



Oh, and I wouldn't panic over a two day count of 12 mites.
Put the board in again for another few days.
Your previous treatment will have disrupted the age distribution of mites in the colony, so over a period of a fortnight or so, the daily counts will vary considerably. As well as the random day-to-day variation.
Don't Panic.

 

[user 6228]

this winter like last winter we will be treating using higher temperatures and higher humidity.

 

[charlievictorbravo]

Thanks for your thoughts

Thanks to the forum members who took the time to offer helpful advice and explanations:-

alanf - I did a check a couple of weeks ago to see whether ants were taking away mites - I checked the monitoring board morning and evening and after each check, I moved the "seen" mites to a small circle in a corner of the board to see if they were still there at the next viewing. I did not find any evidence of ant larceny but these checks did not amount to a proper research trial - just a bit of pottering but it put my mind at ease regarding ants near my hive. I will take on board your advice about a longer period of monitoring.

itma - I did not mention in the original post that I now have stores and brood so am reluctant to use oxalic or further HM Thymol treatment while the winter build-up is underway but I will do more monitoring, even if it affects the way the bees drive off the moisture from their nectar and my 2:1 sugar syrup. I haven't seen any wasps lately so maybe I could open up the entrance a little to give a bit more ventilation.

derekm - I did not understand your comment "this winter like last winter we will be treating using higher temperatures and higher humidity". Are you referring to something meteorological/climatic or to the improved insulation and wind-proofing some of us will be adopting this winter?

drstitson - sorry, I must be a bit dense but I could not following your cryptic posting. Are you saying that my view that "a few mites would not kill them but no stores and no brood certainly would" was incorrect?

jbm - your comments regarding sugared bees are noted!

Thanks All

CVB

 

[user 6228]

Varroa breeding success falls off dramatically with humidity above 75% and elevated temperatures.

 

[TryingToLetThemBee]

As you will see above, I did HM's Thymol treatment in September but stopped part-way through the second phase because I was getting very low drops of Varroa and there was no brood that I could see and very little stores - my thoughts were that a few mites would not kill them but no stores and no brood certainly would. Since then I've been feeding during cool weather and letting them get on with it when they're foraging on Michaelmas Daisies and Ivy.

I put the monitoring board in two days ago and when I checked an hour ago I had 12 mites (all, as far as I could see, dead) on the board. The Beebase Varroa calculator suggests this is indicative of between 300 and 1200 mites in the colony.

What's going on? Where did they all come from and what's the best thing to do with such an infestation. It looks like they're in line for an Oxalic Treatment, which I was hoping to avoid, at Christmas but would they suffer if I did an icing sugar treatment now, while it's still relatively warm?

Thanks for any insights.

CVB

CVB: was poking around and found this post http://www.beekeepingforum.co.uk/showpost.php?p=8439&postcount=22 in what looks like the original HM Thymol thread. "When the bee's are fanning during storing this it also plays havoc with varroa." I've seen a pick up in drops as well so how sweet is THAT?!

<ADD>If you're thymolating the feed, anyway</ADD>

 

[charlievictorbravo]

Panic over - I think!

Following my post above (#85), I had several useful observations from which one common view emerged - monitor over a longer period.
Last Thursday, I started a further monitoring exercise using natural drop onto a monitoring board.
Today I found 10 mites on the board from the 7 day monitoring, which the Beebase calculator indicates that there is between 70 and 290 mites in the colony. That a hell of a lot better than the 300 to 1200 suggested by the earlier 2 day monitoring check.
I did find a lot of condensation on the monitoring board but I suppose that is to be expected - they're taking 2:1 thymolised syrup and bringing in nectar and pollen from the ivy, which is still going strong. Was this high humidity just holding back Varroa development or was it killing them?
Temperature here at the moment is 15 degrees and the girls are still out foraging although the lunchtime weather forecast suggests that won't last for long - big storm coming at the weekend - batten down the hatches!

CVB