Wintering bees outside in a cold climate

[Brian MCquilkin]

This is my second winter wintering bees in Wisconsin.  When approaching my first winter in Wisconsin my thought was how the heck are the bees going to survive in the extreme cold. It's not uncommon to get temps in the -25 F. I spent quite some time talking to local beekeepers, the hobby beekeepers with a small number of hives had 100% losses. I'm sure there were probably some out there that had survived but I was not able to find them. I did speak to some Commercial beekeepers and asked what was the secret to keeping bees in the Cold winters of Wisconsin. One said he had not found the answer to that question and he was 3 gen commercial beekeeper with about 2500 colonies.
All of the commercial beekeepers I spoke to moved their bees south for the winter. Buying packages of replacement bees every year s not an option that I can afford. When Spring arrived I was surprised to see that I had bees that came through the cold extreme winter and I was able to make a significant increase last spring to my apiary.
Based on my experience from last winter I made the decision to the following.
1: Cull out any weak colonies.
2: Make sure that the mites were under control before the end of August.
3:Good young Queens.
4: Good nutrition.
5: Good weight of food going into winter.
6: wrap each hive. 2" insulation on the sides and 4" on top Plus wrapped with tar paper.
7: No top ventilation.

Last month Jan 22. I decided to get around all my colonies and do some inspections. I was horrified to find that a large number of colonies were light on food. Any that were in danger of starvation I added emergency feed in the form of dry sugar.
This week I did another round of inspections, I found that some had emergency food left,  some still had not touched their emergency food.
This year to date I have 4 dead-outs It's early stages and time will tell.

This winter has been extremely cold and not sure if the bees have even had any flying days since December.
There was one yard I had not visited because of the access to it. 2 days ago I decided to see if I could drive in to check the bees. I sat in my truck knowing if I was to Check those colonies I was going to have to walk in. That was the last thing I wanted to do it was cold but warmer than normal, about 31 F.  I almost left but in the end, I loaded up a one 5 gal pail with my tools and a 5gal pail bucket of wet sugar, put the bee suit on, and off I went.
After the long hard walk in I opened up all the 14 collines at this location, 2 were dead and the other 12 were ok. Some would have been out of food within a day as all they had was about a spoon full of emergency food. I did find 1 colony I thought was dead, but they were still in the bottom box and the top box was a full super of capped honey they hadn't touched or moved onto. I'm sure If I had taken the lazy way out and gone home without walking in to check them, most would have been dead by the time I came back.
The green arrow shows where the bee yard is.

[Acebird]

The last photo looks like a nuc.  Some people sandwich nucs together so there is a common wall.  Insulate around the pair.

[Brian MCquilkin]

The last photo looks like a nuc.  Some people sandwich nucs together so there is a common wall.  Insulate around the pair.

Ace: That's a double 10 deep what you are seeing is a deep box with 4 x 4 inches of insulation with an area for the emergency feed.

[Oldbeavo]

Even in our mild winter we put 2 hives sandwiched together. Our Paradise hives are 2 to a pallet and you will find the queens laying closer to the common wall at times.
We have found that packing bees down very tight, even to singles will winter better than left with a super of honey.
A local BK packs all his 10 frames down to singles for winter, this is done mid Autumn and the bees will pack out the single with the remaining flow. The bees are hanging out the front they are so tight. I ask him was he worried about bees hanging out, his comment was come back on the first cold night and they wont be outside.