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British Beekeepers Association Official Forum 

  • New tool improves beekeepers' overwintering odds and bottom line

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More advanced beekeeping discussion forum.
 #5295  by AndrewLD
 04 Dec 2019, 08:48
I would imagine that as well as the profit/loss calculation there are practical considerations driving cold storage. You can overwinter with just a brood box and not have to worry about supers or hefting or fondant. Plus, if you are in an area that had significant snowfall you don't have to worry about buried hives. The bees are just a tool in the food production process but it makes me slightly uneasy; its the difference between bee farming and hobby beekeepers.

I read Adam's letter with interest. We seem to have radically different approaches with some believing that ventilation is all and the great enemy is condensation whilst others try to emulate the bees in a tree condition and any condensation is used as a source of water without having to go outside (I think that's the argument..).

I guess I go for a halfway house. I try to create a chimney with a sealed and insulated top. The hive stand is an equivalent of a super underneath to keep draughts out, the OMF sits on top, a nadired super on top of that and then the brood box with well-insulated cover board and the brood box wrapped in closed cell "karrimat" that insulates but more importantly keeps the wood from becoming staurated in the winter rain. But the insulation doesn't go on until after the first couple of frosts and I take it off in mid-March because I want the bees to know that W inter is coming and then Spring - I think there is some data that suggests bees in uninsulated hives get going quicker in Spring??
Be interested to know what others do in this country and their rationale....
 #5297  by AdamD
 04 Dec 2019, 13:52
Andrew, I insulate the top of the hive -either a single brood box; nadired super under a brood box or double brood box depending on the size of the colony. Mesh floors are open and they mostly sit on single hive stands. I don't wrap with anything however you are right that saturated wood will not have much insulation value compared to dry wood (I have WBC's in the mix which must help in this regard as the inner boxes stay dry - although they are painfully thin). However I have not noticed any difference between double-walled hives and single with regard to the size of the colony in spring.

IF the BBKA can create a meaningful survey comparing poly, insulated wood and 'gapped' wooden hives and can compare winter losses from thousands of people completing the survey, it would give a real statistical answer to how we should overwinter colonies and would stop the argument in one go.

I have a book somewhere written by a capable beekeeper in the 40's and his winter losses were around 3%, I recall, and he had insulation - quilts and such-like - probably before plywood was readily available and before the practice changed to ventilate at any cost. However we now accept 20% losses as reasonable, it seems. To encourage debate , I would go as far as to suggest that most winter losses are optional as far as the beekeeper is concerned!

It's apparent that I favour insulating hives to some degree. I will say that I will happily eat my words if a better method is highlighted as a consequence of the survey. Result: Benefit to all (bees that is)!

(Post script: The worry is that some people will criticise the BBKA whatever they do and there will be argument and sniping afterwards :( )
 #5298  by Patrick
 04 Dec 2019, 23:59
I get storing hives in refrigerated containers if you are in Manitoba like Ian Steppler - it’s a way to achieve and maintain an optimal cluster without risking - 40 degrees at night and prolonged periods of - 18 in the day. That must push even bees legendary resilience.

I do wonder if the benefits of insulation depend on where you are. In my neck of the woods I have rarely used any to date. I cant think of ever losing a colony attributed to coldness alone.

It’s quite a anthropomorphic perspective to simply assume being cosy warm in winter as optimal - there are loads of species whose overwintering strategy relies on lowering their temperature to allow hibernation or torpidity to survive foraging dearth. If they remain too warm it is fatal.

The difference is perhaps less survival and more how bees might perform the following season. Colonies on solid floors I think come out ahead and I am pretty sure that is even more true for poly hives. If I went to OSR then poly would be the way to go I am sure. In my neck of the woods with later first flows I am currently okay with a typically slower build up that doesn’t peak too early and is then busting to swarm. If I moved my bees to early crops I would probably change tack and kit

More exposed or different areas may find it all very different though.
 #5301  by NigelP
 05 Dec 2019, 13:44
Even as an advocate of poly hives I'm not sure winter survival rates are much different vs wooden hives. I certainly never lost many in wood nor poly. Approx 10% would be about the average.
There are some differences on overwintering; in that bees in wooden hives cluster at higher ambient temps than poly. Obvious as poly retains heat so hives are warmer. Consequently much of the retained heat in a poly hive is generated from the bees normal metabolic activity rather than through specialist "heater bees" burning up the stores. In poly they use less stores and are more active throughout the winter.
The question is which (if any) is better for their overall well being come spring....being active all winter (little clustering)? or clustering where the heater bees are using prodigious amounts of stores to maintain a population of fairly moribund/lethargic bees?
It would be an interesting study, assuming geography is taken into account.

IMHO where poly hives come in to their own is a cold spring where the amount of brood, compared with wood can be vastly different. Not always but sufficient to warrant the use of poly in my area.
In the early days I ran 5 wood and 5 poly side by side in my garden apiary. Come March the poly hives had between 5-8 frames of brood and 4 of the wooden hives had between 2-3. One however had 9.....but this was an exceptional queen that later that year was on three brood boxes and a ladder to to remove the supers that where a hazard to ,ow flying aircraft.
So nothing is 100% and in the Sarth of England or anywhere that has a mild spring I suspect the differences between wood and poly will be subtle and also based on ones own prejudices.

One thing was very obvious, where I live, between wood and poly hives was the amount of honey harvested...I reckon even with similar sized colonies I was getting about 4 supers from poly to 3 on wood... I think that part of the reason is that more heat is needed to maintain temp in wooden hives than poly, so more nectar was used up in generating this heat....just a thought not an fact.

I should point out that these observations have all been made with Buckfast bees, F1's occasional F2's, all sourced from reputable breeders, not the stack 'em high sell 'em cheap type. If we get into comparing different strains of bees it's a totally different ball game come honey production.
 #5303  by AdamD
 07 Dec 2019, 10:06
I have a post-war book on beekeeping by Joseph Tinsley, latterly Head of Beekeeping at West of Scotland Agricultural College, which I have just found, (I knew it was somewhere) in which, unlike many books, he goes into detail of overwintering of colonies.
He writes,
"Bees have been known to winter in almost any kind of hive. They winter best when the hive is properly insulated, which not only saves life but the bees consume a smaller amount of food. Bags or cushions of chaff make the best overhead packing. There must be a space of at least 4" between the inside of the roof (he used WBC's) and the top packing to avoid condensation. ....." .

Under a paragraph called Upward Ventillation he says There is a new school of thought in regard to giving the bees top ventillation in winter and although no actual experimental work has been conducted, many beekeepers claim a considerable amount of sucess.... ...... During the severe winter of 1946-7, winter losses were severely felt in thie country, ranging from 10 - 20 percent. It is interesting to note that in the ten apiaries consisting of over 600 colonies of bees beloning to Messers E H Taylor Ltd of Welwyn, in which I have a personal interest in their preparation for winter, the losses were only three percent. No top ventillation was given. A few had crownboards but the majority were snugly packed with clean sacks"

He is astute enough (to avoid the usual beekeepers' arguments perhaps?) to comment on differing weather across the UK and summarises "The best advice that can be given to beekeepers is that if your present method of wintering has been successfull over a period of years, continue with it. There is no need to change. A new method might be harmful".
 #5307  by NigelP
 07 Dec 2019, 16:32
Very interesting Adam. Thanks for posting that.
The predecessor of the WBC (forgotten name) was a double walled hive meant , as was the WBC, for the gaps to filled with insulation for the winter. Langstroths first WBC was also double walled for the same reason. Insulation was known and used well over 100 years ago. I think the necessities and shortages during two world wars led to the generation of single walled hives....that and cost.
 #5309  by Patrick
 07 Dec 2019, 17:09
I have several Taylor’s of Welwyn hives in daily use, bless ‘em.

I wonder if commercial beekeepers also readily adopted single wall hives as labour was more scarce. Double wall hives are nice at the hobby level but single handed mobile hive operation in the hundreds would be a nightmare surely?
 #5314  by MickBBKA
 09 Dec 2019, 00:12
Chrisbarlow wrote:
06 Oct 2019, 21:47
A new tool can predict the odds that honey bee colonies overwintered in cold storage will be large enough to rent for almond pollination in February. Identifying which colonies will not be worth spending dollars to overwinter can improve beekeepers' bottom line.

Does any one put their bees in cold storage? its an interesting thought.
I have no idea which of my colonies will be best going into the next year. What I have found is never to be surprised that my colonies scraping by on 3 seams of bees in March turn out to be double brood with 5 supers by the middle of June. Then they have a massive brood break in September and you think they are going to die, but they don't and go on into the next season, then you have no idea what happens next..LOL
 #5315  by AdamD
 09 Dec 2019, 09:14
Mick, I too have been surprised by late summer brood breaks - and start to wonder if I need to replace the queen in the belief that she has failed - and lo and behold, they grow rapidly in the following spring.
 #5316  by AndrewLD
 09 Dec 2019, 12:36
AdamD wrote:
09 Dec 2019, 09:14
Mick, I too have been surprised by late summer brood breaks - and start to wonder if I need to replace the queen in the belief that she has failed - and lo and behold, they grow rapidly in the following spring.
If you are not aware of it, have a look at Randy Oliver's piece on build-up and decline in brood

I have learnt to be very wary of assuming queen failure in late summer and am now very reluctant to unite without real evidence of queenlessness and by then it can be too late :(