Re: Michigan first year TBH and big concerns about wintering.
With all due respect, the question was concering a TBH. These photos are of Langs. It has been my experience, which is limited with TBHs, that they usually carry through winter with smaller clusters. Lots of similarities between beekeeping in langs & TBHs but also lots of differences. My first concern now would be to make sure they have food! Move 1 or 2 frames of honey next to the cluster, scratch open the cells on 1 so they can feed if they will. Also was suggested to me to move the bars with bees back enough to put a bar of honey on both sides, acting as insulation. Also if possible remove as many bars as possible with shorting them in stores and use a follower board to make their space more compact. Yes I know they only heat the cluster, but this will limit the amount of cold air around them and any heat loss of the cluster can better add to the temp in the hive.
I would also suggest emailing M Bush or Sam Comfort. These guys have a wealth of knowledge with TBHs and are interested in helping folks be sucessful & do it right. Just a thought. As to your bees, try breeding some Russian into them. My bees have Russian in them. They are very gentle & the fly at 35 degrees if it's sunny with no wind.
Note: If you try the above, it might help if you use some sort of temp wind break if you think it's necessary.
Beeman
All things may be lawful; but not all things are advantagous.
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