Varroa - A Cautionary Tale

[East Yorks New Bee]

Just to let anyone out there who thinks that a nil varroa count means no varroa, I have been meticulously doing drop counts on my hives since I go them back in June.I have seen no varroa to date. Yesterday I did a drone comb culling and this is what I found.

 

[Finman]

.
Jep. It is much and it will weakens the winter bees.

Give now thymol or formic acid gas to the hive.

If bees rob some wild colony, it may get at once a big dose mites from that hive.

 

[mikethebee]

This is the worst time of year for varroa
You have to keep them clear of the mite on the heather to go though the winter otherwise they don’t survive
We also have to continually treat hundreds of nucs that over winter in our apiary’s ready for sale in the Spring and are vulnerable to the varroa
It takes two men a full time job up to the end of December before we can rest
See website for treatment.

 

[m100]

Which might add to the theory I've mentioned on here or on the BBKA board that the mites might be hanging on to the bees better.

I've had so little drone brood this year that culling probably wouldn't give meaningful results.

 

[skydragon]

Which might add to the theory I've mentioned on here or on the BBKA board that the mites might be hanging on to the bees better

can you expand on this point within this thread?

East Yorks New Bee - that's unbelievable (in a bad way). Can you give details on what hive floors you are using and how you do mite counts?

 

[Finman]

* mites might be hanging on to the bees better.

* culling probably wouldn't give meaningful results.

I have never counted my mites but I have looked after worker mites and drone larva mites.

When it is feeling that I have mites at all, in oxalic acid handling I get 300-500 miten on bottom board.

2 years ago I saw every day mites in workers and tens of mites in drone larvae. In autumn mites violated really much wintering bees and winter clusters were half size. It means that the last brood are badly affected. We had extra long brooding year.

So it is time to give 2 handling : in late summer and in winter and slow down number of mites.

.

 

[m100]

can you expand on this point within this thread?

It was just an comment made in passing - so few of us at our local association were seeing 'normal' varroa drops. Zero counts were the norm until the last few weeks which might have been due to the greater break in brood production with the colder winter giving them a lower starting point...or better grip by the mites.

 

[skydragon]

Thanks M100

East Yorks NB - also... out of curiosity, have you carried out any anti-varroa treatments to date? (appreciate you probably haven't done any if zero mite drop count)

 

[Chris B]

It was just an comment made in passing - so few of us at our local association were seeing 'normal' varroa drops. Zero counts were the norm until the last few weeks which might have been due to the greater break in brood production with the colder winter giving them a lower starting point...or better grip by the mites.

The idea of counting mite drop is mainly about measuring natural mortality which gives an indication of the total mite load in the hive. Mites don't hang on when they are dead, so there must be another explanation for lack of dead mites on the floor.

What seems much more likely to me - genuinely low count at start of season followed by exponential growth in mite numbers. This in turn leads to exponential growth in natural mite mortality, but obviously with a bit of a time lag.

Why such a low mite load at start of season? You have it right m100. Apart from improved beekeeping and better treatment, it was a harsh winter last year and the long brood break knocks back mite numbers very well.

 

[DrNick]

Ants eat a lot of mites that drop, so the count will be reduced if you get ants in or under your hive if it has a mesh floor.

 

[adri]

Is there any work going on to develop a better treatment for varroa?

sorry for the newbie question...

cheers

nick

 

[Nopants]

Ants eat a lot of mites that drop, so the count will be reduced if you get ants in or under your hive if it has a mesh floor.

May be we should encourage ants in to the hive to scavenge of the floor? the other possibility is that the mites are becoming more resistant to the varoa treatments as in cornwall and the midlands I believe. I think come the spring I shall be putting in new foundation and doing a shook swarm method to help keep the mites down. I recon the brood combs will be full of mite eggs and before long you have a collapsed colony. It might be worth sacrificing the brood in the name of survival but only when things are stronger

 

[Finman]

.
Counting mites is not a key to handle mites.
in your country brood period is long and mite has time to propagate. They double in month.
So after honey harvest handle with thymol or formic acid that you get healthy winter bees.

Then knock down mites again in december to get low level for brood season. losses happens but dont live on alarm level all the time. It is not worse than loose a hive via swarming.