Re: Dead Colony, Froze to death?
Sounds like a cold starved hive to me. The mold is common. The mass of bees, typically in the center of the cluster holds residual moisture and blocks ventilation. That doesn't mean that you don't also have a ventilation problem, it just means that you might not simply blame it on poor air flow.
When cold weather hits, bees need fuel. They get it from their stored honey. I've seen larger colonies crash very quickly even though there's plenty of honey stores just a short distance away. The larger mass of bees has no trouble generating heat (and moisture) but in doing so, they consume stores quite a bit faster. If they can't break cluster to move to where the honey is, they starve in place. You could call it freezing if you'd like since they really just run out of energy to stay warm. They die from lack of fuel / warmth.
Finally, you could have mitigating factors to their health as well and most of us likely do. Mites, etc., have a negative impact to the overall health and stamina of a colony. I've had winters where a colony surprised me with their strength, going into the winter weak and coming out strong. I've had other winters where the cold cycles and the available fuel has all but wiped out a yard of bees. A lot depends on my time, the bees health, the weather and some luck.
Oh...the dark comb. No problem. It's normal!
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