# Predicting winter feed requirements



## JoshW (Feb 5, 2013)

I know that feed requirements are different in every area and are dependent on what nature throws our way.

My question is directed towards those who winter indoors or have knowledge of the sort, we do not have the temperature fluctuations that those who winter outside do.

Has anyone done a study of the amount of feed bees consume per month at a steady temp of 5 degrees Celsius? 

With temperature constant and assuming the consumption of the average strong single deep of bees, could we not figure out the optimum amount to feed based on the number of months in storage?

If this information is out there could someone please direct me as to where to find it. Thank you


----------



## burns375 (Jul 15, 2013)

You;ll need a few more variables to concoct a decent formula, size of cluster, breed of bees, amount of ventilation, to name a few.


----------



## JoshW (Feb 5, 2013)

burns375 said:


> You;ll need a few more variables to concoct a decent formula, size of cluster, breed of bees, amount of ventilation, to name a few.


As I am new to both keeping bees and indoor wintering this year, I do not have all the knowledge I wish I had concerning these things.

I understand that the bees will adjust their numbers based on the size of the dwelling as well as the temperature. Therefore temperature being constant and a strong hive going into winter, would an average size of the cluster not be something that could be considered nearly constant, as hives that are too strong would decrease their numbers and vice versa?


----------



## Rob Hughes (Apr 23, 2012)

Josh, 
You could try some searches on Google Scholar. Are you able to weigh some of your hives every month or so? This might give you a start on your own dataset, which in the end should be the most useful as it will reflect your reality rather than someone else's tests, which may have been done elsewhere with different bees etc. I am trying accumulated degree days below 10C. My bees are outdoors. Based on what I have read, cluster metabolism increases roughly linearly from +10C to -20C. If your storage shed is roughly at constant temp then probably the use of stores should be steady as well, which should be revealed in steadily decreasing weight.

Rob


----------



## JoshW (Feb 5, 2013)

Yes that is definitely something I could look into doing. I do not really like the idea of moving hives onto and off of a scale once a month, as I do not want to add to their stress. If I could find a platform non digital scale to do this research it would be helpful, I will look around for something. 

When feeding 2:1 syrup how many KGs/Lbs convert to 1 KG/LB of capped stores within a hive?


----------



## Ian (Jan 16, 2003)

This kind of question is hard to answer because there are a few determining factors that play into your equation. 
First and most importantly off, the cluster size, the more mouths to feed, the more honey that will be consumed. 
Second, winter brood rearing. Some races of bees will rear more brood during the winter that others. Carni vs Italian, even indoors.
Third, the indoor wintering environment
Fourth, the quantity and quality of honey vs syrup in the nest. Curse that canola honey under smaller wintering clusters.

Im not going to answer your question because I cant. I have never broke these factors down before as you are. I assume your going to provide us with your conclusions as you go here, right? 
You will be able to do basic math to find the average honey consumption over through out the shed. Hive weight in, hive weight out. If you go further and tie all these determining factors to each hive you should find trends. 

What some guys do is feed their single hives up to 80-90 lbs. They weigh each hive individual hive and feed accordingly. 
I dont weigh my hives, I give them all two pails of syrup, and late in fall shift any remaining pails to use up the sugar syrup. Not very scientific but its quick and if fills them right up. Over feeding does not go to waste as it will be used in spring. Every once and a while I will run into a small cluster that is honey bound, just make space for them. 

Some years I dont get a long enough fall to feed more than one 2.5 gallon pail into them and those years I run in to a bit of starvation in my larger hives. Thats a weather issue.

As far as trying to predict indoor feeding, a scale under a hive is your best option but not very practical. MIne are stacked 6 pallets high so determining a hives short on feed is next to impossible

Hope that helps!


----------



## Allen Martens (Jan 13, 2007)

Ian gave you a very complete answer. There are too many variables to come up with a nice formula. 

Start with feeding heavy - 3.5 to 4 imperial gallons. It is far easier to deal with a bit of extra feed in spring than having to deal with starvation or emergency feeding in winter.

As time goes by you can back off on the feed in fall and see if you are comfortable with the amount of feed the bees have in spring if you want. You may have fall alfalfa flows that will allow you to feed very little. I don't consider canola and sunflower honey winter stores, so even if they are present, I feed as though they are not. Because of this weight alone is not a very good measure of winter preparedness for me.

Every year after I've fed I feel like I might have fed on the heavy side - but I have peace of mind.


----------



## JoshW (Feb 5, 2013)

I ended up feeding each hive 6 gallons this fall, they drank up the first 4 real quick, then slowed down for the next 2. I think they are set based on the numbers Ian and Allen have given. 

I am not interested in weighing all my hives. I may put a scale under one to curb my curiosity. 
I am sure there is a way to get a ratio of lbs of bees going in : Syrup consumed : Average temp for each type of bee.
If the time and effort were put in to do the testing over several seasons. I have not decided if I want to commit to that with my expansion efforts taking up a large chunk of my free time already.


----------



## Ian (Jan 16, 2003)

If you keep your shed warmer, the bees will be more active and consume more. If you keep your shed cooler, the bees will cluster tighter and consume more to create heat which also expels more water vapour, condensation concerns become more apparent. 

Barry Fingler did the research in the 70's as his masters thesis at the U of M and found 5 degrees C to be the optimum temperature to winter bees at. He did his research on exactly the question you have posted here. Most of the guidelines we follow has been based on Barry Fingler's observations. 
Look around some of our local beekeeping literature, and in the Hive and the Honey Bee. You will find more specific answers to your posted questions.


----------



## sharpdog (Jun 6, 2012)

Ian, do you collect and weigh your dead bees on the floor of the barn? I have 68 singles and my current dead bees on the floor weigh about 8 lbs. This equates to 0.12lbs/hive. Do you track this?

Also on topic, 

I have 4 singles on a drum scale. They started the winter Nov 4 weighing 286lbs total. Now they are down to 258 lbs. 286-258=28 lbs /4 hives / 58days =0.12lbs per day x 180 days = 21.7 lbs projected loss bees and food stores. I don't know if it means anything, a month ago the weight loss was projecting 28 lbs in 180 days. 

Just little experiments I'm playing with.
Luke


----------



## Ian (Jan 16, 2003)

I just toss them out the door,

keep us posted on your findings


----------



## Sipa (Jan 1, 2013)

Someone was asking how much of the feed ends up as stores.
Approximately 0.3kg sugar is consumed by the bees per litre of water in the feed.

So, 10 litres of 2:1 (67%) syrup will be 8.91kg sugar & 4.39 litres of water ( this weighs 13.3 kg)

The bees would consume 1.31kg of sugar and store the rest, 7.6kg.

Hope this helps, sorry for using metric but that's what we do in the UK now.

Lots of other factors go to determine the final rate of conversion such as, number of bees, temperature, activity, room, time of year (cycle of the colony) to name but a few.
But the above is a good guide.


----------



## Allen Martens (Jan 13, 2007)

Sipa 1.3 kg of sugar consumed seems very high for fall feeding. I can see this number being true as an average but not for fall feeding.

10 L of 2:1 syrup takes the bees a day or two to empty in fall (in my area at least). I would expect most of this would be stored if they collected this fast.


----------



## Allen Martens (Jan 13, 2007)

Luke I never thought of trying to measuring winter weight loss. Good idea. I have a couple of drum scales kicking around and will try this next year as well.


----------



## Sipa (Jan 1, 2013)

Hi Allen
The Bees might "take it Fast", however they still need to "cure" it, driving off water is part of that process.

0.3kg / litre is an average, and relates to the energy required to drive off water from syrup enabling safe storage by the bees.

A bit like saying bees use 8lbs of honey to produce 1lb of wax


----------



## irwin harlton (Jan 7, 2005)

Has anyone done a study of the amount of feed bees consume per month at a steady temp of 5 degrees Celsius? 

Yes, here
http://mspace.lib.umanitoba.ca/bitstream/1993/6315/1/Gruszka_Indoor_wintering.pdf


----------



## JoshW (Feb 5, 2013)

irwin harlton said:


> Has anyone done a study of the amount of feed bees consume per month at a steady temp of 5 degrees Celsius?
> 
> Yes, here
> http://mspace.lib.umanitoba.ca/bitstream/1993/6315/1/Gruszka_Indoor_wintering.pdf


Very interesting article, I am just getting into it now. The following peaked my interest, within the first few pages.

"Braun and Geiger (1955) showed that the average weight loss
of colonies during winter (thirteen year average) was between thirty-five
and forty pounds (16-18 kg) per colony in Manitoba and that there
was no significant difference in weight loss between outdoor wintered
and cellar wintered colonies"

Based on the numbers provided by Sipa above we would need approx. 24 liters of 2:1 syrup to satisfy average the 18kgs consumed by bees in Manitoba overwinter. This comes out to 6.35 gallons per hive.


----------



## jean-marc (Jan 13, 2005)

Like Ian and Allen mentioned to many variables to give a fast and easy answer but I agree with what they have written. On you post 8 Josh you talk about the speed at which bees consume the syrup. This is the key. When they are light they will take it quickly, as they get heavier they slow down. If they are kinda heavy at the start of when you want to feed them, they will take it slower than if they would be lighter. There is just less processing room. You can kinda gauge how heavy they are based on the rate of feed consumption. This is not highly accurate. However based on feeding 3 pails of syrup, assuming they are the the 2.5 gallon ones, I would say your bees will be fine. Sometimes only 1, usually 2 and if they are Italians many get a third bucket but never 4.

Jean-Marc


----------



## Allen Martens (Jan 13, 2007)

Interesting read Irwin. A good article from what must have been very frustrating results and circumstances to work with. 

The research is not very definitive but was probably quite pioneering in its time. Very few obvious trends. After the way the singles were made, temperatures reach 22 C for 12 hours twice, hives were fed syrup but water content was not accounted for seemingly, hives moved in very late and treatments applied at varying time, the study can best be viewed as a starting point. I didn't come away with many answers but sure came away with many questions - some of which question my theories and practices in beekeeping. 

The lost of bees during the first flight days for indoor wintered bees was truly disturbing. I wonder is the high nosema infection rates played a large role as the infection rates seemed to decrease dramatically. It would also be interesting to see what the results would be for putting 200 paint dabs on worker bees after being outside for 2 weeks - maybe the paint is effecting the bees or something else is at play. I will be watching this closely this spring.

I am also certain the high nosema infection rates for the indoor hives greatly reduced brood are and populations, so makes the comparisons with packages and outdoor wintering hive marginally valuable.

I found it interesting that no mention of swarming was made. Large to average singles should have had bees handing in the trees all over the place by the end of June.

This studied also found that indoor wintered hives had very little to no brood when they were first moved out. Several of us felt this was the case in another thread.


----------



## Allen Martens (Jan 13, 2007)

JoshW said:


> Based on the numbers provided by Sipa above we would need approx. 24 liters of 2:1 syrup to satisfy average the 18kgs consumed by bees in Manitoba overwinter. This comes out to 6.35 gallons per hive.


Not sure if this matters but if you are basing you feeding on this it probably does. 23 L is 6.35 US gal but only 5.27 imperial gallons. Seems very high from my experience and communications with others when wintering singles indoors. They may have been wintering doubles - didn't even try to check the original research. Only monster hives would come close to needing this much. Now if you are talking Italians ...


----------



## delber (Dec 26, 2010)

To enter another variable. . . I've had hives that I knew were light and sought to feed them only to have them not take it. They were on their way out due to mites. WIthin a month they were dead and not because they didn't have stores left in the hive. In this instance the thought of "if they take if fast" wouldn't work. They took like 2 weeks to get the first gallon down.


----------



## JoshW (Feb 5, 2013)

I also found the information to be quite inconclusive. I believe this was to be year one of a 5 year study. Would be interesting to see the final conclusions after year 5.


----------



## JoshW (Feb 5, 2013)

Allen Martens said:


> It would also be interesting to see what the results would be for putting 200 paint dabs on worker bees after being outside for 2 weeks - maybe the paint is effecting the bees or something else is at play. I will be watching this closely this spring.


The research you seek is on Adobe page 98-100 of this paper.
http://mspace.lib.umanitoba.ca/bitstream/1993/6645/1/Fingler_The_Effect.pdf


----------



## delber (Dec 26, 2010)

JoshW said:


> The research you seek is on Adobe page 98-100 of this paper.
> http://mspace.lib.umanitoba.ca/bitstream/1993/6645/1/Fingler_The_Effect.pdf


This paper only goes to page 82. And there are only 10 introduction pages. (Including cover page) I didn't look through it because I just wanted to see the specific info.


----------



## Ian (Jan 16, 2003)

The amount of bee mortality on first flight has way too many variable to be able to determine the expected bee loss when putting the bees out. One year is different than the next. 

Look at last year for example, terrible conditions, lots of bee loss. But the year before that it seemed the hive numbers increased! 

Bottom line, pick a good calm sunny spot, set them out of the wind and pick days when the day time temp rises above 10


----------



## JoshW (Feb 5, 2013)

delber said:


> This paper only goes to page 82. And there are only 10 introduction pages. (Including cover page) I didn't look through it because I just wanted to see the specific info.


page 65 - 72 for those who don't have Adobe reader, or know how to read a table of contents.


----------



## Allen Martens (Jan 13, 2007)

>pick a good calm sunny spot, set them out of the wind and pick days when the day time temp rises above 10<

Very valuable unpublished research from the school of hard knocks.


----------



## JoshW (Feb 5, 2013)

Allen Martens said:


> >pick a good calm sunny spot, set them out of the wind and pick days when the day time temp rises above 10<
> 
> Very valuable unpublished research from the school of hard knocks.


The most valuable research comes out of that school.


----------



## Ian (Jan 16, 2003)

Walked in my shed today, these hives are a busting! Hefted a few boxes on top and they are good and heavy. I see why guys use to winter with that extra medium on, piece of mind!

My neighbour is wintering all his hives outside in singles again. He has got to be worried about stores right now. It's been so cold for do long now that one would "expect" the bees to be burning through that food!


----------

