Hello All, At this time of year "good" beekeepers should be tending to their bees rather than pondering theories. Sometimes I do my best thinking while I am doing bee work. (There is something a psycho-analyst can spend days on.) As with all theories if you throw them around enough sooner or later you will find someone to agree with you. Disclaimer: This post is probably going to be a rambling of thoughts that have been going through my head the past few months (being driven by the bee loss I had this winter) trying to answer questions that start with "why". Some I have answers, others I am not too sure. Hopefully, you will also ponder these and come up with your own thoughts or ideas. Observation: I maintain an observation hive at a nature center. It was built BM (before mites) so the design does not allow for easy treatment. I had trouble keeping it going for a few years (mid '90's) but now it has been up and running for almost two years without any treatment. It has a screened bottom with a debris pan underneath. I have not seen any varroa in the pan. This colony is doing well on its own. WHY? Observation: I lost colonies this winter. Some were due to Apistan resistant varroa. Some probably to tracheal mite (TM). But I still have problem blaming it all on mites. Colonies that were protected from wind survived much better than those in the open. Somewhere in the back of my head the weather keeps jumping into my thoughts. WHY? Known fact: Bees survive in very cold climates, and very warm ones too. My climate is neither. So WHY do I keep going back to the weather issue? I have no experience keeping bees in very cold or very warm climates, or do I? We are seeing 100 F days with 80% humidity in the summer (sounds like Florida), and 0 F degree days with -30 F wind chill in the winter (Canada?). Beekeepers will be quick to point out that bees do well no matter what the weather and my problem is somewhere else. Possible, however the weather is changing. In my area the past few winters were mild. Bees are flying around at Christmas. Ten years ago this was uncommon. This past winter was the same but we had severe cold spell. I lost a number of colonies during that period. If a colony has TM and they take a cleansing flight on a "warm winter day" they may not make it back causing the population to dwindle. Eventually they cannot maintain cluster temperature and perish. Theory: Let's assume there is no mite problem. What do bees do on warm days in the winter? They fly around looking for forage just like they would any other time. These are not cleansing flights, and some may fly a good distance from the colony. If they do this towards the end of the day the temp may drop and they may not make it back, causing the population to dwindle. If the weather stays mild this may not affect the cluster and they will survive the winter. But what happens if this goes on for a month or two and then a few weeks of really cold weather sets in. Those smaller clusters will have trouble surviving. The whole scenario resembles TM so the beekeeper writes it off to mites. A few years back I started switching from Italians to Carniolans. One reason was because of the smaller winter cluster and a break in the brood cycle. Could this cool weather trait work against them in a warm/cold winter? I found someone who agrees with this theory. Actually he is person who proposed it, and it fit well with my thoughts and observation. He mentioned that in the 12th century bee houses started showing up in Europe. This coincided with a warming trend in the climate. The bee house would keep the colonies cool on warm winter days and prevent them from flying. I don't know much about the history of bee houses but it makes sense. The honey flow will not be extended because of warmer winters until plants become established. This takes time. But if you artificially control the climate keeping things cooler the bees will be less affected. I am not a weather expert and I can only comment on what I actually observe, but I think this theory has some merit. It may only apply to small fringe areas. You probably don't want to think about winter at the beginning of summer, but if you do care to share your thoughts on this I would like to hear them. If this is a problem it will be the first one in while that we won't try to control with a new chemical. Also, if anyone has knowledge on the evolution of bee houses, it would prove to be interesting. Take care, Ron Bogansky Kutztown, (eastern) PA, USA