dampness as cause of colony death

[wondervet]

Dear All,

Often see the statement that it's the damp not the cold that kills 'em.

Just wondered what is the evidence for this? and how does it kill them?

Just curious. Thanks in advance for feedback.

WV

 

[oliver90owner]

I makes them cold, of course!!

 

[susbees]

I makes them cold, of course!!

And fermenting stores much more likely with increased humidity in the hive. Lots of water got to evaporate when honey stores used.

 

[mbc]

dampness causes low morale

 

[Finman]

.

I have experiences about that

1) 45 years ago I learned it. I had 6 one box hives. 4died and 2 stayed alive.
What was the difference. Dead colonies has no upper hole and alive had upper entrance open.

When the hive consumed food 10 kg, it generated almost 7 litre water. It comes when oxygen from air join the food.

The moisture goes into the food even through the cappings. Food swells and bees try to easte everything. Finally they swell them selves.


2) I have killed really big hives too when I have feeded too much. They store it along the wall but they are not able to cover it in Autumn because of cold. The open food suckds moisture and it ferments. Bees try to eate it and they become sick and come out to die.

3) If the hive air is not in condition, they get nosema. Even if the colony does not die totally, half of cluster will die. Then the rest are not able to rear brood because nosema has spoiled nurser bees gut. That happens if the wintering cellar has not electrict ventilation. That is very usual.

Under wet snow it happens partly too. Snow ids not a good cover if it is often wet like in South Finland.


I have seen that a honey frame in a cold shelter alone soaks moisture. Food swells and drills out.

.

 

[Finman]

I makes them cold, of course!!

At least it makes the wooden wall cold when when water condensates onto the surface. Water filled wood has no insulation properties.

What about moist clothes? Does it keep your warm?

Rain is one which goes into the untreated wood. When it evaporate, it keeps the wall cold. - So, paint the wood.


Lead the moisture out and don't let the rain to soak into the hive material.

 

[bees4u]

At least it makes the wooden wall cold when when water condensates onto the surface. Water filled wood has no insulation properties.

What about moist clothes? Does it keep your warm?

Rain is one which goes into the untreated wood. When it evaporate, it keeps the wall cold. - So, paint the wood.


Lead the moisture out and don't let the rain to soak into the hive material.

Hi Finman, I love reading your replies, someone with great experience and may I say thanks for sharing this with us on this forum. But I think I might disagree with you about painting hives, surely cedar hives which must of us have in uk do not need painting, it has to be better for the wood to breath, I've used raw linseed oil in very dry summers & it does stop that green mould on the hives in winter. kind regards Jean

 

[For want of a better word]

I've used raw linseed oil in very dry summers & it does stop that green mould on the hives in winter.

We were told by THE area expert not to put anything on hives or boxes... and to ventilate all colonies crown boards up on matchsticks, open mesh or not!

Warm air from bees metabolism will carry away any dampness surely? therefore some ventilation is required, and as a topic of another thread... also a reasonable level of insulation.

Take point on dressing the timber with a wood oil of some kind... as a waterproof... but most seem to be cut with turpentine or some similar spirit that I would have thought would need to be kept away from bees?


Any one experience of damp problems with polyhives.... it seems to me to be the way to go!

OR Skeps !!!!

 

[drstitson]

mould, fermenting stores, fungal disease etc etc.

great evidence from FERA and BBKA winter losses surveys - last two winters (cold and dry) losses well under 20%. previous winter (3 years ago) - mild and damp - losses somewhere between 25 & 30%.

although the forum is excellent i don't imagine that it has singlehandedly improved the husbandry of the whole UK beek'ing population to that extent so evidence points to supporting the mantra that damp kills.

 

[drstitson]

"Warm air from bees metabolism will carry away any dampness surely? "

straight onto nearest cold surface where it will condense.

 

[Finman]

"Warm air from bees metabolism will carry away any dampness surely? "

straight onto nearest cold surface where it will condense.

yes it surely does. Arrange so that it is not a wrong place like hole in the middle of inner cover.

Sidewalls and the bottom are allowed places. Tilt a hive a little and water comes out from solid bottom.

 

[For want of a better word]

straight onto nearest cold surface where it will condense.



GOOD REASON TO INSULATE CROWNBOAD ROOF !
as per another thread

Although cold.. have never seen any condensate on the metal mesh of an omf..... heat rises, but if it can not escape via a vented crownboard, would surely set up a current within the hive
... now were getting into "GeeK land"!

 

[user 6228]

straight onto nearest cold surface where it will condense.



GOOD REASON TO INSULATE CROWNBOAD ROOF !
as per another thread

Although cold.. have never seen any condensate on the metal mesh of an omf..... heat rises, but if it can not escape via a vented crownboard, would surely set up a current within the hive
... now were getting into "GeeK land"!

did some one call

 

[Finman]

.
Just a while ago I made some hive parts in my shelter. I sawed with table saw and put on face the dust mask. My respiration went right to my eye glasses and I saw nothing. Temp was +10C in the shelter.

In winter when you come indoors, do your glasses go misty? That is condensation on cold surface.

Same with car windows. The dew point goes over very easily in the car when warm person is sitting there.


if the colony consumes 10 kg in 100 days, it produces water 7 litres = 7000 g. It is 70 g a day.

If it half that much, it is 35 g a day.

Human lungs produge half litre water in room temperature per 24 hours.

.

 

[drex]

Think there is a difference between " dampness" ( whatever you are meaning) and air humidity. A fridge is cold but the air has very low humidity. A sauna is hot but has high humidity. Las Vegas is hot but has low humidity. Finman talks of wet and dry snow.

Water in a hive will only come from outside or from bees respiration. Yes, when an animal metabolises food, the breakdown of carbohydrate will produce water. That water however is used by the animal for it physiological needs, or is excreted in Urine ( by us, for example) or in the faecal matter ( by us and by bees). It will not create water vapour in the hive in excess of that normally generated in the course of respiration.

I am fairly new to beekeeping but to me an OMF with top insulation, is the most sensible way to deal with the problem of water vapour problems in winter.

 

[Nose Ma]

Water in a hive will only come from outside or from bees respiration. Yes, when an animal metabolises food, the breakdown of carbohydrate will produce water. That water however is used by the animal for it physiological needs, or is excreted in Urine ( by us, for example) or in the faecal matter ( by us and by bees). It will not create water vapour in the hive in excess of that normally generated in the course of respiration.

Not quite - we do breath out one hell of a lot of water vapour. Ever wondered why you had steamy breath on a cold morning, or why glass fogs when you breath on it?

 

[Finman]

Yes, when an animal metabolises food, the breakdown of carbohydrate will produce water. That water however is used by the animal for it physiological needs, or is excreted in Urine ( by us, for example) or in the faecal matter ( by us and by bees).

It will not create water vapour in the hive in excess of that normally generated in the course of respiration.

.

Up till now bees had generated moisture from the metabolism. A dead insect dry up quite soon.

For its physiological needs ......what?

Bees piss somewhere? ....where....never heard

 

[drex]

Sorry Nose Ma and Finman, you missed the point or I did not explain it well.

Yes we and bees breathe and that breath will contain water.

However, if we or bees break down carbohydrate that will produce water. That does not mean there will be any more water in our breath. Any animal will use that water for its own metabolic needs or excrete the excess ( us in urine, bees in faecal matter). Hence no matter how much honey is broken down by bees, it will not increase the water content in the hive.

 

[For want of a better word]

GOT IT ... a DRY hive is a HAPPY hive

Waterproofing roof with big eves a must have !

 

[Nose Ma]

I still think I'm missing the point.

Are you comparing bees in the hive on a summer's day to bees in the hive in the depths of winter - and saying that, give or take, the water vapour output is the same in both scenarios?

Or are you thinking about the dew point, which is the temperature to which the air in the hive would need to be cooled for the water vapour to condense? If the latter then, well, warm air can "hold" more moisture than cold air. So warm moist air in contact with something cold (or below its dew point) like a car windscreen, or the sides of a hive, cause the vapour to condense.
A hive is cooler in the winter, even a polyhive is not a perfect insulator, so the inside of the walls will be closer to (or below) the dewpoint of the air inside, so the water vapour condenses.
This is a Very Bad Thing if it drips on the bees. Even on the insides it will chill the hive if it evaporates again (this is kinda how a fridge works). That's part of the reason wet clothes are so cold as well.
The answer is to try and stop the air in the hive holding too much water vapour. We do that by allowing air to circulate, letting (generally) drier atmospheric air in and the built up vapour from bee "breathing" out. I am sure on some days, such as when it's foggy, the two are very close indeed to water content per litre.

I think the point being made is that too much water vapour in the hive makes the hive damp - like a wet pair of jeans. That, in turn, chills the bees, who try to vibrate more to get warm, metabolise more, "breathe" more, emit more vapour, raising the water content of the air (and the dew point) so the problem gets worse.
I don't know if you have ever been camping, but if it's really cold you will find ice on the inside of your tent. You will have breathed and sweated that out overnight. Eww. It's the same effect.

The other part of the debate was "how much ventilation?" Clearly removing the hive would be the maximum, but other exposures would kill the bees.
Some advocate none other than the entrance.
Finman opts for a hole drilled near the top of the frames
others just have an open mesh floor
And others have an open mesh floor, and the crownboard lifted on matchsticks
I am sure others have different ideas.
My personal preference is just the OMF, which is based on the idea that it allows some circulation, even if only by Brownian Motion, but not a howling gale like a chimney. Also, should water condense on the sides it can dribble out, not be re-evaporated to chill the sides/bees.

NM