# How many bees die per day overwinter?



## Marcin (Jun 15, 2011)

I know this questions is totally dependent based on your location, so please answer based on your location. 
Let's assume that a colony going into winter is healthy, mites have been managed and there's no disease issues. They have enough food stores and a healthy laying queen. According to Dave Cushman, a deep Lang frame has about 1500 covering it http://www.dave-cushman.net/bee/beesest.html. Let's assume that on November 1st there were 10 seams of bees, so you're going into winter with 15,000 bees, and there's no brood at that time. Let's assume that there is no stimulative/emergency feeding over winter, and let's factor in periodic brooding over the winter. How many bees will you have on March 1st? I've heard that, on average, about 200-250 bees die per day in a healthy "normal" colony over winter. That's ~24,000 dead bees between November-March. Does that sound plausible? If a colony has 10,000 bees on March 1st, it means that they raised ~19,000 bees over the winter? 
Thanks for any help you can provide.


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## Robbin (May 26, 2013)

How long a bee lives changes dramatically when the bees are in winter. Bees "wear out" more than die of old age, so they don't wear out over the winter when they are not foraging. So the 200 - 250 dead bees a day for a normal colony goes out the window during the winter. No way does a hive raise 10s of thousands of bees over the winter. I would bet it's more like hundreds.


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## Marcin (Jun 15, 2011)

Robbin said:


> How long a bee lives changes dramatically when the bees are in winter. Bees "wear out" more than die of old age, so they don't wear out over the winter when they are not foraging. So the 200 - 250 dead bees a day for a normal colony goes out the window during the winter. No way does a hive raise 10s of thousands of bees over the winter. I would bet it's more like hundreds.


Thanks Robbin, I was thinking something similar. I've heard it mentioned in a talk I attended, and quite possibly the speaker was saying that , on average 200-250, bees day a day over the whole season, summer included, and I just didn't get the whole explanation. That would make more sense anyways, since the math didn't add up.


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## Vance G (Jan 6, 2011)

Long ago, North Dakota State University research at the time put out data that 1 1/2 % of a hives population died per day. I don not remember the supporting material just that number but when you look at the dead bees in the snow around a hive, I imagine it is pretty close.


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## Outdoor N8 (Aug 7, 2015)

Bees live longer in the winter, to a point.
I just read a thesis of sorts that addresses this topic over on Randy Olivers' site:http://scientificbeekeeping.com/scibeeimages/fig-0214.png

One chart in particular was an attention getter to me.


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## Robbin (May 26, 2013)

Outdoor N8 said:


> Bees live longer in the winter, to a point.
> I just read a thesis of sorts that addresses this topic over on Randy Olivers' site:http://scientificbeekeeping.com/scibeeimages/fig-0214.png
> 
> One chart in particular was an attention getter to me.


Thanks Outdoor N8, that was a very interesting chart. Some of the oldest winter bees where over 200 days old, while the oldest summer bees was only in the 60 to 70 day range.


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## Bdfarmer555 (Oct 7, 2015)

I'd also add that in the winter, 20 frames of bees can cluster tight enough to fit into just the top box, possibly doubling your starting population in the op


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## Barhopper (Mar 5, 2015)

I've always heard, like Robbin said, they wear out. Like mileage on the wings. They don't fly nearly as far in the winter. Probably why they a testier this time of year also.


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## A'sPOPPY (Oct 13, 2010)

Please take the time to study "fat bees" and the effects of Vitellogenin in honeybees and this stuff will make more sense


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## capitalbeesupply (Jul 28, 2013)

Marcin said:


> I know this questions is totally dependent based on your location, so please answer based on your location.
> Let's assume that a colony going into winter is healthy, mites have been managed and there's no disease issues. They have enough food stores and a healthy laying queen. According to Dave Cushman, a deep Lang frame has about 1500 covering it http://www.dave-cushman.net/bee/beesest.html. Let's assume that on November 1st there were 10 seams of bees, so you're going into winter with 15,000 bees, and there's no brood at that time. Let's assume that there is no stimulative/emergency feeding over winter, and let's factor in periodic brooding over the winter. How many bees will you have on March 1st? I've heard that, on average, about 200-250 bees die per day in a healthy "normal" colony over winter. That's ~24,000 dead bees between November-March. Does that sound plausible? If a colony has 10,000 bees on March 1st, it means that they raised ~19,000 bees over the winter?
> Thanks for any help you can provide.


The number that I read in a old report was 2.4% per month....that report was pre-varroa. That same report stated that the winter bees did not die in relation to their age, meaning the oldest bees weren't always the ones dying off first. In that same study they marked the bees that emerged in October and some of those marked bees were still alive yet the end of June....again that was pre-varroa. Some of the varroa research in later years suggested that the winter bees that were damaged/infected by varroa during development have a substantially shorter life span (one report I recall stating it was 50% shorter.....

Rich
Capital Bee Supply


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## WBVC (Apr 25, 2013)

I have an observation hive. Either they are really efficient at hauling out their dead or very few die. I rarely see a dead bee on the bottom of the hive.


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## Marcin (Jun 15, 2011)

WBVC said:


> I have an observation hive. Either they are really efficient at hauling out their dead or very few die. I rarely see a dead bee on the bottom of the hive.


That's more in line with what I see in my backyard hives. Every morning I "clear" 8-12 dead bees from in front of the hive entrance.

Thanks to everyone who replied.


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