Mould and Hive Ventilation

[Nick Sonic]

Hi, I visited my hive over the weekend and unfortunately found that my bees had died; there was mould inside so I presume it became too damp.

The colony had developed from a nuc I got in June, I had a full super with a 14x12 brood box on top, a small amount of insulation under the lid with the crown board holes open. My floor was open mesh although I'd kept the inspection tray in but given that it's been so wet over the last 2-3 months would keeping the tray in have made any difference...?

Quite disappointing, needless to say.

 

[Erichalfbee]

Hi, I visited my hive over the weekend and unfortunately found that my bees had died; there was mould inside so I presume it became too damp.

The colony had developed from a nuc I got in June, I had a full super with a 14x12 brood box on top, a small amount of insulation under the lid with the crown board holes open. My floor was open mesh although I'd kept the inspection tray in but given that it's been so wet over the last 2-3 months would keeping the tray in have made any difference...?

Quite disappointing, needless to say.

I suspect closing the crown board holes would have been your best bet.

 

[jenkinsbrynmair]

and leaving the inspection tray out.

When you say you had a full super 'under' when precisely did you put it under?

 

[Nick Sonic]

I suspect closing the crown board holes would have been your best bet.

Could you explain how that would aid ventilation? If I want ventilation in my house i'd open windows at the front and back, not have one side open and the other shut.

 

[Nick Sonic]

When you say you had a full super 'under' when precisely did you put it under?

Mid-October.

 

[Erichalfbee]

Could you explain how that would aid ventilation? If I want ventilation in my house i'd open windows at the front and back, not have one side open and the other shut.

Your hive doesn't need ventilation in the winter. It needs insulation and to be weatherproof.
Open or partly open mesh floor/reduced entrance, mouse-proofed in some manner and 50mm PIR insulation directly on the crown board.

Hot air at the top will displace cold air at the bottom which will drift through the OMF and provide enough ventilation.

 

[jenkinsbrynmair]

Could you explain how that would aid ventilation? If I want ventilation in my house i'd open windows at the front and back, not have one side open and the other shut.

How often do you leave the bedroom windows and the back door open in the middle of winter?
You don't need 'ventilation' in a hive - the bees will sort that out
Leaving holes in the crown board would just have ensured a roaring gale blowing through the hive which wouldn't have helped the bees at all.
Solid crown board, OMF open and the bees will balance air supply out themselves - never seen mould in my hives.

Mid-October.

If the super was full of capped stores there is no sense in putting it under the cluster if the super had some uncapped stores in then you may have considered nadiring it but a lot sooner to give the bees a chance to rearrange things for winter.
A 14x12 packed with stores is more than enough to bring a colony through winter, but if it was fairly light because they'd filled the super then nadiring it that late would mean they wouldn't have been able to get at the stores and probably died from isolation starvation

 

[Hivemaker.]

What was the varroa situation, mite counts, treatments used and when etc..

Did you make sure the queen was okay and normal brood present after this super re arranging operation.

 

[Nick Sonic]

Your hive doesn't need ventilation in the winter.

I'd read that the cause of mould in a hive is due to a lack of ventilation, which makes sense to me.

 

[Nick Sonic]

What was the varroa situation, mite counts, treatments used and when etc..

Did you make sure the queen was okay and normal brood present after this super re arranging operation.

I hadn't actually found any varroa during the season so I didn't treat for it. Inspection tray checked every time I visited the hive, etc.

Everything looked fine in the hive after moving the super, given the fact that the weather was so incredibly mild i wouldn't have thought mid-October was too late to make that change.

 

[jenkinsbrynmair]

I hadn't actually found any varroa during the season so I didn't treat for it.

And you honestly think there was none there?

i wouldn't have thought mid-October was too late to make that change.

Way too late

 

[Swarm]

Dead bees will go mouldy.

 

[jenkinsbrynmair]

I'd read that the cause of mould in a hive is due to a lack of ventilation, which makes sense to me.

you been reading BBKA publications again?

 

[jenkinsbrynmair]

Dead bees will go mouldy.

dead bees can't sort out hive ventilation either

 

[REDWOOD]

Not knowing the state of your hive when you last inspected but obviously your colony had grown to produce a super of honey. They didn't starve to death with still stores in the super, no signs of varroa mites so this leaves a few possible causes; failed queen, nosema, foul brood, or poison. mould probably appeared after the bees died, get your dead bees checked for nosema or other nasties.

 

[jenkinsbrynmair]

But the super had been nadired way too late - may as well have just been taken off altogether as the bees wouldn't go down to it - they move up during the winter

 

[REDWOOD]

Perhaps nick can post a picture of the dead bees on the frame, it would be interesting to see if the bees heads are inside the cells.

 

[jenkinsbrynmair]

Perhaps nick can post a picture of the bead bees on the frame, it would be interesting to see if the bees heads are inside the cells.

 

[Erichalfbee]

I'd read that the cause of mould in a hive is due to a lack of ventilation,.

No.....which is probably an oversimplification but will do till we see some pictures.
Mould will occur in a damp hive. A hive gets damp if water gets in from outside or if water condenses. Water won't condense in a hive if the box is warm enough.....ie insulated.
Like folk have said, take some pictures of the frames and perhaps we can help you diagnose the problem.

 

[Millet]

I stuck several bags of Silica Jell on my crown board, it killed the bees but stopped the mould.