Low Varroa in ‘23

[polomadh]

2023 has been an interesting year weather wise in the NW, with a long hot dry spell and then a cold wet spell with over 300% more rain in Preston Than average. Curiously I am seeing very little evidence of varroa damage across all my hives and multiple apiaries. Usually at this time year I am fretting about timing varroa treatments vs leaving supers on for the HB flow. Varroa drop on the boards is low. I am assuming that some kind of brood break has interrupted the normal expansion.

Has anyone else noticed this?

The wet and now warmish weather looks like we will get a good HB crop, with supers filling and bees coated in pollen

 

[jenkinsbrynmair]

Varroa drop on the boards is low.

but a highly inaccurate and unreliable method of determining the varroa load of the colony

 

[gregior]

2023 has been an interesting year weather wise in the NW, with a long hot dry spell and then a cold wet spell with over 300% more rain in Preston Than average. Curiously I am seeing very little evidence of varroa damage across all my hives and multiple apiaries. Usually at this time year I am fretting about timing varroa treatments vs leaving supers on for the HB flow. Varroa drop on the boards is low. I am assuming that some kind of brood break has interrupted the normal expansion.

Has anyone else noticed this?

The wet and now warmish weather looks like we will get a good HB crop, with supers filling and bees coated in pollen

Same for me here, pretty much all my colonies have tried to swarm this year so have all had brood breaks and varroa levels seem much lower than usual which is great as i'm able to leave supers on later to hopefully grab some balsam honey.

 

[blackcloud]

Pride before the fall?

 

[enrico]

I learnt long ago not to count the varroa drop until they are dying from treatment. Then, despite all hopes there are usually more than I can be bothered to count

 

[polomadh]

I do feel that my point has been missed. I am not saying I have no varroa, just that typical evidence of varroa, DWV, actual mites on bees, floor drop and drone culling have shown much lower varroa evidence this year across 35 hives in 10 separate apiaries.

I will still be treating once the HB flow has stopped, as I do every year.

Perhaps my observations are restricted to this years temperate rainforest that is the Ribble Valley.

 

[Ian123]

I do feel that my point has been missed. I am not saying I have no varroa, just that typical evidence of varroa, DWV, actual mites on bees, floor drop and drone culling have shown much lower varroa evidence this year across 35 hives in 10 separate apiaries.

I will still be treating once the HB flow has stopped, as I do every year.

Perhaps my observations are restricted to this years temperate rainforest that is the Ribble Valley.

Are you now treating in Winter?

 

[Steve at Westerham Beeks]

@polomadh Do you see any signs of your bees interrupting varroa reproduction? Eg; Uncapping brood at the pink-purple eyed stage or chewed-out infected pupae exoskeleton (white) on the insert board?

 

[Mabee]

Mine are the opposite. Especially one hive I used for queen rearing.
So in addition to a brood break and treatment over winter, I spotted bees out the front of the hive last week with DWV and mites.
So got the supers off and treated the other day.
Day one this was the board!

 

[polomadh]

@polomadh Do you see any signs of your bees interrupting varroa reproduction? Eg; Uncapping brood at the pink-purple eyed stage or chewed-out infected pupae exoskeleton (white) on the insert board?

No

 

[Paul_Ward1]

but a highly inaccurate and unreliable method of determining the varroa load of the colony

There’s a study (apparently) which is often quoted from but never cited which links dead mite drop to live population levels (I think it is quoted at 10-15%). I’d like to read it but can’t find it online. The recent article in bee craft had a study comparing the methods. I’d like to read a decent study comparing the methods which includes mite drop. Does one exist? The ones I am aware of don’t include this. Thanks.

 

[Erichalfbee]

I can’t quote a study but I have always worked on 80% in the brood 20% on the board after an accelerated drop, if there is brood.
Natural drop can be accurate if you measure over a month and check the boards every day. Hardly worth it if there are better methods to see if the bees need treating or if you have bees that are living well will varroa.

 

[Murox]

There’s a study (apparently) which is often quoted from but never cited which links dead mite drop to live population levels (I think it is quoted at 10-15%). I’d like to read it but can’t find it online. The recent article in bee craft had a study comparing the methods. I’d like to read a decent study comparing the methods which includes mite drop. Does one exist? The ones I am aware of don’t include this. Thanks.

Not sure if this will answer your question but skip to pages 29 & 30. The whole thing examines mite drops.

 

[user 819]

My garden colony dropped approx . 400 after the first vape , now just had their second vape.
Another nearby garden /orchard location and the two colonies have dropped very little almost non exsistant from what I can see , they to had a second vape today.

 

[The Poot]

24 hours after first vape, I had these results
10, 148, 7, 3

There were two brood breaks in the colony of 148. Swarmed twice.
7 was a captured swarm, 3 was a split and subsequent supercedure, 7 was a swarm.

 

[Erichalfbee]

24 hours after first vape, I had these results
10, 148, 7, 3

There were two brood breaks in the colony of 148. Swarmed twice.
7 was a captured swarm, 3 was a split and subsequent supercedure, 7 was a swarm.

The drop will depend on the amount of brood.

 

[Macbear]

A most interesting article, Murox, thankyou. Sugar roll seems a far more bee-friendly method of counting mites, but the thought of counting exactly how many bees could be a challenge. The rough measure of the Americans - a 1/2 cup measure = 300 seems a fair approximation. With a percentage error being fairly small using that may there be a balance with the potential error caused by the sheer luck of the draw: the sample may contain more or less than the average infestation rate anyway.

 

[Murox]

A most interesting article, Murox, thankyou. Sugar roll seems a far more bee-friendly method of counting mites, but the thought of counting exactly how many bees could be a challenge. The rough measure of the Americans - a 1/2 cup measure = 300 seems a fair approximation. With a percentage error being fairly small using that may there be a balance with the potential error caused by the sheer luck of the draw: the sample may contain more or less than the average infestation rate anyway.

Thats part of the reason why many take a profilatic approach, and as @enrico points out best intentions regarding varroa "are usually more than I can be bothered to count".

 

[markb2603]

OMG not here. Drop count after first 24 hours of Apilife Var.

The other 3 hives were much lower though.

 

[jenkinsbrynmair]

doesn't look a particularly horrifying amount to see during treatment