# Heater Bees, Bees in the Snow



## A Novice (Sep 15, 2019)

crofter said:


> ....
> 
> I think we can agree that bees will lose moisture in respiration and that the *only* sources of resupply are from honey consumed, atmospheric humidity or free water fetched in.
> 
> ...


Hi Frank,
I was thinking about this yesterday evening, and I wondered, the water which is produced when bees metabolize sugars - is it in liquid form, or vapor form? I am guessing it is in liquid form, but I am not a chemist.

If bees gain water by metabolizing sugars, It isn't clear how much they lose through respiration. For example, camels and hibernating bears are known to go months without drinking water, because they get enough water from the fat they metabolize when they are not near water. I am not suggesting that the ability of camels to go without water shows that bees could do the same, just that it is possible for some organisms to do this, and therefore it could be possible for bees also.

It has been my observation that if there is no brood rearing going on, the bees use very little of their stores. If they were getting too dry, they could loosen the cluster, making it larger and more porous. This would result in increased heat loss, requiring more metabolic activity to warm the larger cluster. Thus, they would lose more heat while possibly gaining water. Also, the outside of the cluster is about 45F normally. This temperature could be increased significantly, also requiring more water to be produced.

So I looked at my hives, which are insulated and ventilated. The temperature outside is around 30F. While most of them show no signs of life, one of them has the top entrance plugged with bees. These bees appear warm. Are they intentionally blocking the entrance to hold in moisture and/or heat, or just hanging out enjoying the hot spot? I suppose the air coming out of the top entrance is quite warm. Sorta like a bee sauna. Maybe they will run out and jump in the snow to cool off... My mind is wandering.

I once was a guest in a Finnish sauna on the coast of the Baltic Sea. After getting way too hot, I ran outside and jumped in. I survived but see no good reason to tempt fate again. Anticipating I would get overly warm, I tanked up on really cold water before going into the sauna and tolerated the extreme heat better than the other victims of this ritual, which impressed my Finnish hosts not a little. I suppose that was cheating, but they never knew....

Too many questions, too little information.

Jon


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## crofter (May 5, 2011)

Not simple is it? The trouble with loosening the cluster and shedding heat is that the heat goes into the surrounding air. The more air is heated the more moisture it will contain. We think of cold and damp but that is relative humidity we are associating with. Absolute moisture content can be much higher as air temperature rises. Now when we vent it off we send out MORE moisture. If we can cool it at the front hive wall it will surrender some of its now surplus(at that temperature) water. If we use less venting off of this warm air at the top it is forced to vent out at the bottom entrance and some of its moisture may condense on lower surfaces.

In short maintaining higher than optimum temperature makes it harder to hang onto water if we have to vent to control temperature. Eating honey to produce water when its caloric value is not needed seems to have some negatives. My guess is metabolism of honey leads to increase in body fluids. Bees can produce free water to spray from their mouth parts to create evaporative cooling. Probably analgous to our spitting. Randy Oliver refers to water bottle bees but I think that is liquid water in their stomachs or honey guts. Maybe different from recovering it from circulatory body fluids.


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## Gray Goose (Sep 4, 2018)

IMO some extra water is put in cells.
Just cleaned up my first dead out, it was expected, dink with very little stores doing poorly over 2 years, and I let it go.
when cleaning 2 frames contained a lot of water, like 20% of the cells, I though that was odd. carefully checked for lid leaks and found none.
So there could be a storage pool to fill and take from, they could even leave some behind as they go up in winter a few cells here and a few there.
they may eat honey burn the 72% sugar for fuel, Store some of the 17 % water in cells for later when brood rearing.
so IF they can and do store , then this can be done in fall as well.

GG


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## A Novice (Sep 15, 2019)

crofter said:


> Not simple is it? The trouble with loosening the cluster and shedding heat is that the heat goes into the surrounding air. The more air is heated the more moisture it will contain.


Hi Frank,
You may be right, but I'm not clear on that.

If the bees eat more, because the cluster gets bigger, it doesn't mean necessarily that the water that results ends up evaporating into the air. That the air, being warmer or more of it, would hold more water is true. However, It isn't clear that the water ends up there. It might, but it might not. It isn't even clear the air is warmer.

If the cluster is say 6 inches in diameter, and it increases to 8.5 inches in diameter, the surface area and the amount of heat carried away by convection, will double at the same cluster outside temperature. If the food consumption also doubles, the air will be no warmer, and the tendency of the air to carry away water should be no greater..

Varying cluster size can dramatically change heat transfer in the hive. This isn't true when it is very cold, as the cluster can only be so small.

Completely without evidence, I suspect the bees are able to regulate temperature without getting too dry or too wet, over a fairly broad range of conditions. Getting too hot should not be a problem, unless there is very little ventilation. This would make sense to me, since bees form nests in all sorts of cavities, with all sorts of thermal properties. As long as they are protected from the wind, they seem to survive. That is my romanticized notion of wild bees, anyway.

That would explain why bees seem to survive and even thrive in the wide variety of wintering arrangements we expose them to.

The size and location of the cluster, the type of winter weather (how cold, how long, how wet, and how variable) the variety of bees, and the extent of available stores would, I suspect, significantly affect where the optimum point lies.

All of that said, I don't know how one would begin to find the best operating point. How to find a better operating point is simple (but not easy).

Starting from a known acceptable point and doing gradient searches from that point (picking variables like insulation and ventilation, and trying two values of each variable, +I, +V,, +I and +V, for example would work.. Maybe a better approach would be to look at water dynamics in a few hives over the course of the winter. Perhaps, as Grey Goose suggests, the bees stockpile water in the cells, so within a much broader range of parameters, the water problem may be no problem at all.

One thing I do know is that to do any meaningful experimenting, I would need more colonies.

Jon


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## crofter (May 5, 2011)

"If the cluster is say 6 inches in diameter, and it increases to 8.5 inches in diameter, the surface area and the amount of heat carried away by convection, will double at the same cluster outside temperature. If the food consumption also doubles, the air will be no warmer, and the tendency of the air to carry away water should be no greater.".

Having difficulty following this.

"Varying cluster size can dramatically change heat transfer in the hive. This isn't true when it is very cold, as the cluster can only be so small."

The possible problem though is when the temperature is elevated and air is too dry, and honey is being consumed to free up water. Honey consumption releases further heat. Seems like a run away situation

"Completely without evidence, I suspect the bees are able to regulate temperature without getting too dry or too wet, over a fairly broad range of conditions. Getting too hot should not be a problem, unless there is very little ventilation".

I would phrase that as bees can and do regulate temperature and humidity within a certain range but we can set them up with situations that exceed their abilities. Greatly reduced heat loss in their surroundings is not something they would commonly face in wild survival conditions. We could handily induce it though with excess insulation.

"That would explain why bees seem to survive and even thrive in the wide variety of wintering arrangements we expose them to"

Except when they dont!
There is a wide range of survivable but sub optimal conditions that we can affect. If we set them up so they have to waste honey, and sacrifice population to control hive moisture, even if surviving, was there not more we could have done?

I think there is an inherent problem when we try to use more ventilation to shed heat and increase available water, in that it results in further loss of *available* moisture. It is not the heat that is the initial villain but the low relative humidity that results in dehydration of the bees. Part of the excess heat was produced by the bees attempting to free up water. When they consume more honey they accumulate more waste in the gut. Bees in the snow!

Temperature, humidity and ventilation are bound together. Very difficult to affect one without impacting the others. It is not going to be easy to connect and explain all the factors at play. I am sure there will be many who simply throw up their hands and accept 25 or 30% losses. There are operators though that have come up with a set of parameters that yield say 10% losses. For the most part they wont be able to argue the physics of why their system works.
For the entrant beekeeper who perhaps does not have a consistent set of circumstances and no back trail of experience to rely on or the ability to do the trials necessary it is going to be hard to learn it on his own.

Personally l like the challenge and enjoy picking at the pieces to figure out exactly what makes things tick!

Edit; I should say "in an attempt to figure out what makes things tick". Far from being there!


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## wildbranch2007 (Dec 3, 2008)

My hives are not insulated in any fashion, and I have 2 screws placed on top of the inner cover, under the outer cover for ventilation. Have never lost a hive to moisture, except over wintered nucs. Do find frames of water located on the outside of the brood chambers at times as someone stated above. You might want to include in the discussion the CO2 affect on the bees. Here is some additional information from bee-l. My way works, I don't spend much time thinking about it, good luck. LISTSERV - BEE-L Archives - COMMUNITY.LSOFT.COM


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## Gray Goose (Sep 4, 2018)

If the bees eat more, because the cluster gets bigger, it doesn't mean necessarily that the water that results ends up evaporating into the air. That the air, being warmer or more of it, would hold more water is true. However, It isn't clear that the water ends up there. It might, but it might not. It isn't even clear the air is warmer. 

FYI Novice as the cluster gets bigger each bee eats less.

GG


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## crofter (May 5, 2011)

We have to define bigger here; bigger in size or bigger in numbers of bees. One denotes density and surface area and the other not directly.


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## Gray Goose (Sep 4, 2018)

crofter said:


> We have to define bigger here; bigger in size or bigger in numbers of bees. One denotes density and surface area and the other not directly.


My comment is bigger is higher number of bees

IMO there is a " too small" spot where each bee needs to eat so much to keep the cluster warm it has to poop before spring.

there is a "just right" spot where "each" bee eats enough to create the needed heat while not overly filling itself with waste.
So poop in the spring works.

from there "Too big" I do not believe exist, I have wintered a 5 deep once and 4 deeps several times they come out crazy strong.
they do need "enough" stores obviously and this is the playground I want to bump "up to". I think rather than 4 hives 5 deep, I'd rather have 6 hives 3 deep and 2 5x5 NUC due to having 8 queens in spring VRS 4, SO for me the "sweet" spot is where I can get the most queens AND the most pounds of bees thru winter. The pounds of bees help with spring splits, the number of queens allow more genetic material in spring.

yes IMO some combination of insulation and air flow / per pound of bee would be a nice chart to have.
Intuitively the small pounds of bee would have/need the most insulation and some minimal air flow and the large pounds of bees would/could have a bit less insulation and a bit more air flow.

so I think some sort of feeding rim with holes, where you open or close some to correspond with cluster size and stack height. I feel the insulation can be a constant and jockey the other 2, so I can have hives be the same, rather than 3 different hive wall thickness and 3 or 4 lid configurations.
can do something interesting like a 1 inch built in foam wall standard with 3 inch foam lid standard, then add a dummy frame to each side of a 10f box to leave 7 frames of bees IE 1.5 frame thick dummy of insulative material. then try to winter a 7X7 Nuc. Here where I am I think doable. then I am leaning toward a 1/2 screen bottom board, empty box, under 2 boxes (deep) with 7F of bees then the rim and quilt box with the plastic "Ukrainian style" . I have a forsterner bit 11/16 seems to be close enough to a wine cork for me to somehow have a handy supply of air flow restriction devices (AFRDs) or corks if it easier to follow that idea.

My 2 double deep long hives do not have an upper entrance but do have a complete screened bottom, so IMO upper entrance is for snow or bee clogged bottom entrances, and optional, seems with the screen bottom there is enough air flow/exchange to keep from suffocation, and minimize moisture loss. open air space under frames, seems like a bee tree, and some hive designs. the vids Greg shows do not have upper entrances, So if the snow issue can be resolved, and the dead bees piling up I would prefer no upper entrance .

Pending the survival outcome this spring seems a good base plan to march forward with. the 2 double deeps and 6 of 7 of the Buckeye hives have bees in now. I will be adding the wall hives with the characteristics I described for a 4 hive test next winter, (they are currently set for 2 inch foam ) 2 sides permanent, 1 side shared, One side removable..
built in a 2 colony unit, so the center is shared. I'll comment on the survival this spring, when I can be assured they will make it to first blooms.
be interested Crofter how the plastic addition worked for you.

GG


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## crofter (May 5, 2011)

Yes, I thought you were referring to number and not the expansion and contraction of the cluster. I like the idea of a basic amount of wall insulation which is not hard to add to. The insulated followers are very adjustable for both R Value and volume adjusting. A large colony to occupy the space is much more efficient in energy usage so I think it may be proven that it could be detrimental if the colonies heating consumption requirement does not result in the freeing of adequate moisture from honey consumption. Amount of ventilation can be a factor here but it is complicated by its tendency to remove hive moisture. This is something I will play with more. You are in a cold climate probably not that different from mine. What I am doing experimentally this year is driven by the hunch that I have been hurting my position by removing too much moisture. Survival has been good but I have been going in heavy with honey and really really light on mites.  I suspect that I may have been burning honey unnecessarily to provide moisture which I have done so much to eliminate! The jury is still out on that matter.

Due to the undeniability of European success without upper entrances we know they are not essential. They do generally have much more bottom ventilation which I expect is to compensate. The possibility of having that become blocked would in my mind have to be taken into consideration. I like the idea of also having an emergency top entrance that could be opened to serve in an emergency. Just my need to have both belt AND suspenders.

The value of empty space under the brood boxes is supported by both Etienne Tardifs and Derek Mitchels research.

I wish I could easily observe more of the area covered by the plastic. I am limited to about an 8 by 8" view over the cluster. Playing it by ear.


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## LAlldredge (Aug 16, 2018)

crofter said:


> Yes, I thought you were referring to number and not the expansion and contraction of the cluster. I like the idea of a basic amount of wall insulation which is not hard to add to. The insulated followers are very adjustable for both R Value and volume adjusting. A large colony to occupy the space is much more efficient in energy usage so I think it may be proven that it could be detrimental if the colonies heating consumption requirement does not result in the freeing of adequate moisture from honey consumption. Amount of ventilation can be a factor here but it is complicated by its tendency to remove hive moisture. This is something I will play with more. You are in a cold climate probably not that different from mine. What I am doing experimentally this year is driven by the hunch that I have been hurting my position by removing too much moisture. Survival has been good but I have been going in heavy with honey and really really light on mites.  I suspect that I may have been burning honey unnecessarily to provide moisture which I have done so much to eliminate! The jury is still out on that matter.
> 
> Due to the undeniability of European success without upper entrances we know they are not essential. They do generally have much more bottom ventilation which I expect is to compensate. The possibility of having that become blocked would in my mind have to be taken into consideration. I like the idea of also having an emergency top entrance that could be opened to serve in an emergency. Just my need to have both belt AND suspenders.
> 
> ...


Is your goal for 90% or 100% survival? That is achievable in a fine tuning kind of way. A small top entrance for me is mandatory. Too easy for the bottom to get plugged out. Love the water subject because too much is destructive and too little is fatal. Vivaldi boards covered in burlap has been part of the answer (take away moisture) and feeding a sugar slurry (moisture back in) has been the other. I quite enjoy my winter routine. Just refreshed their slurry yesterday and cleaned lower entrances on a few. Will go back and clean the rest of the lowers today.


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## Gray Goose (Sep 4, 2018)

Hi Frank

re:
Due to the undeniability of European success without upper entrances we know they are not essential. They do generally have much more* bottom* ventilation which I expect is to compensate. The possibility of having that become blocked would in my mind have to be taken into consideration. I like the idea of also having an emergency *top entrance* that could be opened to serve in an emergency. Just my need to have *both* belt AND suspenders.

there is more than either, or, and both 

my long hives have an entrance mid the bottom frame, and open space under the frames (5ish inches)
and no top entrance.
what about a side entrance, above the bee pile and snow blockage? leaving most of the cluster above the hole.









entrance has about 1.5 deep lang frames above it 1/2 x 5 inches no upper or lower. tin overhang mostly keeps the snow off.
could do a Greg and bore a 1/2 inch hole in every box as well.
cork a couple, leave a couple etc.

the option are too numerus to list..

GG

GG


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## crofter (May 5, 2011)

I agree that we dont have to stick religiously to absolutes. If we were running 3 sq. inches upper entrance area, then reducing to 1/2 a square inch would be a great difference. That is about what I used last winter. It is enough for emergency if a sole bottom entrance were to become totally plugged. That can happen! 

I think it was in one of Tardiffs examples of cluster area heat loss, charting different entrances, that showed a central entrance at about the height of the bottom of the cluster having little effect in comparison to the same area at the extreme top. Vance G uses a one inch hole below the handhole of upper box with very good results.

The greater the height of the heated column, the greater is the stack effect. That is not a matter of opinion. Also the greater the average temperature of the column of air the greater the stack effect and the influence of area of opening. That too is not opinion.

Perhaps by wording that suggests ALL upper ventilation is bad we are hindering acceptance that a whole lot less might be better.

There is quite a bit said, perhaps by Bill Hesbach for one, that in *an uninsulated hive* with just an inner and a telescopic cover, *top ventilation is necessary to carry away resulting condensation* that would otherwise melt and drip on the cluster with deadly results. That was the major reality for a large part of the beekeeping community for literally hundreds of years. That common knowledge has a lot of inertia.* Condensation needed to be removed.*

Relatively cheap and available foamboard insulation is a game changer. Using it, *condensation on upper surfaces can be redirected to occur lower in the hive and then need not be swept out by rapid air exchanges.*

That condensate that we have prevented from occurring on upper surfaces now has to be dealt with below. If overall temperature is high enough some will leave as vapor via the bottom entrance but a large amount can build up in the form of ice and block off a lower entrance especially if it is cluttered by dead bees and the essential mouse guard apparatus.I am not a fan of screened bottom boards but they do serve as prevention of asphyxiation if bottom entrance gets iced over.

There is considerable belief that bees can suffer dehydration from too dry hive interior surfaces. Some fine tuning of the amount and location of deliberate condensation surfaces could use some tinkering. I dont know how to quantify how much is needed. Probably lots of variables feed into it.


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## crofter (May 5, 2011)

Below is a copy of a post by Etienne Tardif on the Bee-L forum It is Etiennes interpretation of a chart put out by Randy Oliver and he links to it at the bottom of the post.

It is regarding the effect of ventilation on essential humidity levels in a colony and the bees mechanism of honey consumption to bring it back into acceptable range. Honey consumption for the reason of hive moisture regulation certainly is not widely accepted. I think is is more common to consider honey consumption as creating excess moisture that must be eliminated.







*ubject:* Winter Cluster RH Management Cold Dry Air*From:* Etienne Tardif <[log in to unmask]>*Reply To:*Informed Discussion of Beekeeping Issues and Bee Biology <[log in to unmask]>*Date:*Fri, 24 Dec 2021 14:17:54 -0500*Content-Type:*text/plain*Parts/Attachments:*text/plain (21 lines)
*After reading the article Steering Humidity Factor and seeing that he had seen many similar colony events that I am seeing I did another quick deep dive into my humidity and temperature data. This time using the hourly data. My goal was to understand the heating events I see regularly from a moisture perspective.
There is a definite relationship. I reviewed 2 weeks of December data and chose one of the heating events to understand it using a psychrometrics.

The Heating Mechanism for dealing with dry cold air (low of 0.25g/m3 vs cluster range of 11 to 14 g/m3): (Hypothesis)
-RH% looks to be dropping 1-3 hours prior to heating event
-RH% drop at constant temperatures equals cluster water loss through consumption (thirsty bees) and loss through venting & dry air intake (O2 need for meta heat generation)
-Heating events increase cluster T by 5C +/- 2
-Heating event requires increased metabolism therefore increased honey consumption (more metabolic water) producing excess water
-Heating event increases Absolute humidity in cluster (RH is 16% higher than it would be if the moisture was held constant for the temperature increase)
-Cluster than drops temperature back to steady 20C+/- 1 or 2
-Drop in temperature increases RH% to maintain desired range








Cluster RH Adjustment.pdf







drive.google.com




Ref: Randy Oliver - 77g of water in 17% moisture honey, plus 211 g of metabolic water produced from the digestion of the sugar, from a pound of honey.*


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## A Novice (Sep 15, 2019)

Interesting pdf.

So apparently, bees in very cold dry ambient conditions will periodically briefly increase their food consumption in order to generate more water as needed. In these conditions the risk of overheating the colony seems pretty small. The temperature increases are pretty significant, about 5C.

This appears to be somewhat in agreement with my perspective that bees are well designed to survive in a wide variety of environments and living situations.
It isn't quite clear yet if this leads to a best way of wintering bees in any particular environment, but it is helpful.

I did a rough calculation, based on my recollection from some years back that in January in SE Wisconsin, my bees used less than 5 pounds of stores. If my recollection is correct, then the colony is less than a 10W heater. Not a lot of power dissipation.


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## crofter (May 5, 2011)

That is pretty much the way I read it too. I dont think overheating is any risk factor _per se. _The possible problem I see is that in a colony that has an over abundance of moisture loss (venting) that the then necessary honey consumption creates issues. Either in unaffordable stores consumption or build up of gut contents requiring voiding.

The heating incidents charted are only intermittent in a fairly tight hive, but in a worse case scenario of really cold conditions with very dry air and *larger than optimum venting*, then a runaway condition *might ensue *where the bees,even with continuous efforts could not bring the moisture levels back to livable. What would such a scenario look like?

Some times to perceive the nature of rather small effects we have to project them to extremes; blow them up so to speak, in order to get our minds around them.


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