Forced varroa drop and selection of hives

[drex]

I have just done the last OA vape of my bees. One hive has a remarkably lower drop than the other hives, hence I assume have a lower varroa load.

I raise my own queens, and let me state that I do not consider that I am a queen bee breeder, I just select queens whose hives show the most desirable traits, and cull heavily those I do not like. My Virgins open mate with ( presumably ) mongrel drones. I do not want to get into a debate about breeding.

My hives went into winter of roughly equal strength, with equal stores, however I do not know what state of brooding from hive to hive, nor the rate of natural bee death over winter, from hive to hive.

Am I being too simple minded to think that the hive with the very low drop rate, has handled varroa better than the others, so might be in the running for selection for this trait next year?

So far I have selected for honey production, calmness on the comb and temperament, but now want to factor in how they handle varroa. I know there are a lot of assumptions in my thinking, and next season I intend to do pin killing to give me more info to go on.

Before proper breeders pour any scorn on my simple, humble attempts at selection, let me just say that the qualities of my bees has improved over the seasons, but this is not what I am enquiring about, rather my simple idea that these bees might be handling varroa better.

 

[fatshark]

Lower drop might just have some/more brood and they're all hiding in capped cells.

 

[madasafish]

Lower drop might mean they don't raid weak hives with high varroa.
Or
You might have vaped them incorrectly.
Or
They were more tightly clustered and the OA did not permeate the cluster.
Or
The OA was directed at the section of the hive with few bees.
Or
The mites in that hive are resistant to OA and you should immediately kill the entire mite content of the hive and their bees as well as collateral damage.
Or..


Devil's advocate hat off..

 

[eddyh]

[
Or
The mites in that hive are resistant to OA and you should immediately kill the entire mite content of the hive and their bees as well as collateral damage.
Or..

Bee's have no resistance to oa as far as i am aware.

 

[Beefriendly]

I have just done the last OA vape of my bees. One hive has a remarkably lower drop than the other hives, hence I assume have a lower varroa load.

Drex try it and see...but don't be surprised if its a false horizon. As others have pointed out there are many other possible reasons. I'm bemuised by varroa levels in my own hives. I currently have some that despite 4/5 (what appeared to be) succesful treatments in September?October are now dropping over a 100 mites a week (after further OA treatment)...most are dropping very few.
There is much we need to understand. Just been reading a Randy Oliver article where he's talking about varroa bomb hives thta have large numbers after treatment....seems he's puzzled by them as well...

 

[drex]

Thanks all. I know that I am assuming a lot, but it does seem a reasonable place to start. Will be interesting to compare the numbers of bees and brood in this hive to my other hives when I do first inspection. As I said I intend to do pin killed assays before any selection.

 

[charlievictorbravo]

..... Just been reading a Randy Oliver article where he's talking about varroa bomb hives that have large numbers after treatment....seems he's puzzled by them as well...

I'd be interested in that article as well - Erichalfbee and I both had similar colonies that dropped loads of mites (4900 in my case) that was only cleaned up by the application of Apivar in accordance with the manufacturer's instructions. This battle over several weeks was documented in an earlier threads - here's one. but we were unable, like Randy Oliver it seems, to come up with a firm conclusion as to the cause.

Is there a link to the Randy Oliver piece?

CVB

 

[Beefriendly]

Is there a link to the Randy Oliver piece?

CVB

January 2018 issue of American Bee Journal...you will need to subscribe to read it though.

 

[Erichalfbee]

I'd be interested in that article as well - Erichalfbee and I both had similar colonies that dropped loads of mites (4900 in my case) that was only cleaned up by the application of Apivar in accordance with the manufacturer's instructions. This battle over several weeks was documented in an earlier threads - here's one. but we were unable, like Randy Oliver it seems, to come up with a firm conclusion as to the cause.

Is there a link to the Randy Oliver piece?

CVB

Just got a years digital sub. Will get back to you when it arrives later

 

[Beefriendly]

Just got a years digital sub. Will get back to you when it arrives later

Yes the digital subscription is peanuts. Had to nag them to send me my access codes though!

 

[Fusion_power]

Drex, where you are is where I was in 2004 when I found a single colony that had very few varroa. I was fortunate enough to obtain 10 queens from Dann Purvis who had been selecting for mite resistance. I used the Purvis queens to produce drones, then mated queens raised from my resistant queen.

For reference, my 2004 colony dropped less than 100 mites in late September when other colonies were dropping thousands. I treated with Apistan which was still effective at that time and counted the dropped mites. When I carefully examined the colony after a couple of weeks, I was unable to find any mites either phoretic or in brood. There were also no mite droppings in cells. I concluded that the colony was mite resistant to a level I had not previously seen. Breeding to the drones from the Purvis queens was effective at stabilizing the traits.

The last time I treated my bees for varroa was the fall/winter of 2004. From 2005 to date they have managed varroa on their own. At the time I got the Purvis queens there were very few if any feral or managed colonies in the area I used for mating. There are dozens of feral colonies in that area now after I pushed my bees to swarm heavily in 2006 and 2008.