Well I guess if you do it long enough its bound to happen. I have been at it for 2 years now and have never experienced the loss of a hive. I have 3 hives all wintered with 2 deeps and a shallow, and a candy board on top of that. I winterized this year just after halloween and haven't checked on them too much since. We had an unusual 60 degree day here last week and I noticed one of the hives didn't have the activity that the other two had. Checked it out and all bees were dead, don't really know how long they had been this way. Little to no brood. The bottom box was pretty empty. They still had frames of honey in the top box and hadn't even touched the shallow. I took some pix in hopes to get some thoughts from you folks. I guess the goal here is to learn from what has happened. There are quite a few butts up and heads down but I would think it is way too early in the winter to have them starve. My other thought was weak from mites and I did see what I think is the mite droppings (although picture kinda stinks). Any input would be appreciated.

First opened up....
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Lotta butts showing....
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Not sure how well this shows up, the frame is upside down so the white "flakes" would be on top of the cells.....
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The aftermath....
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