My goal with this post was to continue gaining hard evidence/learnings about perfecting my overwintering approach. If your current system works (<10-20% winter loss) for you then I don't recommend you change anything. I am currently in that range and my base approach is set. 

I am a big advocate of continuous improvement. The only way to achieve this is to ask questions, own the failures (what could I have done, or what did I do or not), ask why 5 times.  https://www.mindtools.com/pages/article/newTMC_5W.htm (more complex approaches exist but this one is the simplest).

Harbo states that the 1st cycle of mixed brood takes about 121g of honey to raise ~1000 cells worth (163 mg of honey to rear one worker bee to the pupal stage). I don't have access to the full study to better understand time frames. (Location Baton Rouge, Louisiana)
Effect of brood rearing on honey consumption and the survival of worker honey bees, John R Harbo (https://www.tandfonline.com/doi/abs/10.1080/00218839.1993.11101282)

Considering the 1st brood nests are fairly small (fist size) initially and really limited by the cluster size (heat conservation) this seems like a small amount. Experiment location is great (as a comparative) because it is not a very cold location so heat input would be minimal vs more northern climes.

I attached an example of how I dealt (analyzed) my 1st winter losses 3 winters ago. It was also the year I trialed top entrances on my hives. Due to my low number of hives I tend to go all in to get a better comparison.

For those who don't get the attached pictures - here is a link (the flow diagram titled " Poor Winter Prep" is the one attached - https://www.northof60beekeeping.com/north-of-60-research-projects/northern-nosema



             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html