Varroa treatment

[Jon]

Business as usual again this year.
I hardly see a mite all year and then see a daily drop of 6-8 mites in September.
I start treatment with Apiguard and get 150 from a 6 frame colony in the first 24 hours.
You can kid yourself that a colony has no mites but the reality can be quite different.

I reckon that 150 on the first day could be a total number of around 1000 which is as much as a colony could tolerate before serious damage occured.

I heard a lecture last weekend which stated that 2000 mites was the level where varroa started to pose a lot of problems re. vectoring viruses.

[Jimbo]

Hi Jon,

Careful with the treatments!
Have a read of this
http://scholar.lib.vt.edu/theses/ava...d/lmburley.pdf

[Jon]

Lesser of two evils!
Has Apiguard been implicated in the reduction of drone fertility or queen impairment?

Your link mentioned Apilife var which is a thymol based treatment.

[Jimbo]

Apiguard has not been implicated but is Apiguard not Thymol based similar to Apilife var?
The sperm reduction and viability in Queens although shows a significant result is only a small reduction in the overall amount available and you would not be treating hives normally for varroa when there is a lot of drones about.
Now I wonder what happens to sperm numbers and viability with Oxalic, Formic, Lactic etc.

[Neils]

My personal feeling over the past couple of years is to ignore the natural mite drop. My observations compared to conventional wisdom is that observing natural mite drop, either alone or in conjunction with icing sugar dusting, severely underestimates the levels of varroa in a colony. Let colonies have a decent amount of drone brood and uncap throughout the season. I've been phasing out foundation but I give my colonies (14x12) at least 3 standard national frames at the moment so I get lots of drone brood. periodically I uncap this to check mite levels and I've been surprised at the amount of varroa in some compared to what the natural drop suggests.

[quoteI heard a lecture last weekend which stated that 2000 mites was the level where varroa started to pose a lot of problems re. vectoring viruses.[/quote]
I'm going from memory right now but I'm pretty sure we teach that 2000 is "going to die" levels of varroa rather than starting to cause problems (I believe US levels are 5,000+)

[Jon]

Hi Nellie:
It was a Swiss AMM guy called Balser Fried who quoted those numbers at the Bibba shindig last weekend. He reckoned that 2000 was on the cusp and 1000 was a safer limit.
He has used small cell for a number of years and did a talk on that as well. He found that small cell reduced overall varroa numbers but not statistically significantly.
Small cell is one of those beekeeping areas which attracts religious devotees so he wasn't deterred. From the data he showed there was certainly a slight advantage re. varroa in using small cell.

I imagine it depends on colony size as well.
1000 in a nuc would probably kill it.

2000 in September is probably survivable with immediate treatment.

[Calum]

We use almost exclusively formic acid and oxalic acid.
At the bee meeting last night one guy was saying he has treated 3 times now and had about 1000 mites each time from the same colony.
Reinvasion is a big problem here. Weak (especially wild) colonies and from colonies where 'beekeepers' are not treating at all.
I hope the weather will hold up for my seventh treatment tomorrow.

[Neils]

I've just completed an Apiguard treatment on one Colony, am halfway through on another and have just started on the colony I suspect will perhaps be far more interesting.

The colony just finished had a total mite drop over the 4 weeks of perhaps 5-6 mites. As I hadn't inspected or removed the floor during the course of the treatment there was a fair amount of debris but even carefully sifting through it I was hard pushed to find much evidence of Varroa.

The second colony that I've just swapped trays on I have taken a look at the floor in light of the results from the first colony. Counts on this one after 2 weeks were maybe 10-15 mites in total.

Daytime temperatures here are well above the recommended and I've followed the instructions to the letter but the counts on sunday were a bit of an eye opener.

The common link at the moment between these two colonies is that they are both splits from the one I had in spring and, as such, were both started either as the Queen right side of an artificial Swarm or from a frame of brood containing Queen Cells started in a Nuc. That being said, at the time these were started, neither were treated in any way and other than Drone brood uncapping neither have received any further treatment over the course of the year.

For a number of reasons, I've only just started the treatment on the "Brood" Colony from the Artificial Swarm. This has also received no treatment other than one super frame of drone brood being removed so I'm going to be very interested in the mite drop from this colony which for obvious reasons I'm expecting to be much higher.

Before the artificial swarm I treated the colony with a single tray of apiguard back in April, at that time I had 2-3 mites in total and didn't bother with the second tray. Having regularly uncapped drone brood over the season with this colony it's never appeared to reach a mite level requiring serious attention and the drone brood removal was more down to the comb getting damaged than anything else.

I'm not reading too much into this at the moment, but I was more than a little surprised by the results on two different colonies.

[Jon]

My personal feeling over the past couple of years is to ignore the natural mite drop.

Hi Nellie.
I would tend to agree with you as lack of mite drop can give a false sense of security.
I have heard several beekeepers recently state that they are not going to treat this year because of the low mite levels.
It will be interesting to se if they still have bees in April.

Between April and August I probably didn't see more than a dozen mites in total and since the Apiguard treatment started I have been removing between 50 and 150 from the inserts per day. I checked a few yesterday and most of the queens are laying.
one colony removed a lot of pupae but in general the Apiguard seems to be working well.

[beebreeder]

I raise queens and use thymol as my only treatment, I have used oxalic once and only once I had more q/less or drone layers the following spring than I have ever had, I have not used it since and things are back to normal, I know Pyretheroids seem to make drones dry! and obviously unless we are making our own f/dation or using Top bar hives!!!! then all the foundation by now has some residues in, but having said that this has been one of the best summers in years for queen rearing down south, how has it been in Scotland.