I went to see one of my friends bees today and it seems like they are all dead in the cluster. He saw them 2 weeks ago and they were flying on a sunny day. When we saw them today the bees were clustered across 4 frames in a deep hive body. They had plenty of honey in store near the cluster. How can I find out what killed them? If I send a few of them to the bee lab will they look under the microscope and tell me? What are some signs to tell you that there was too much moisture that killed the bees? How exactly does moisture in winter kill bees? Does it form water that drops onto the cluster and freezes? If thats the case, then I don't think it was a moisture problem, since the bees were not covered in ice.
I don't think they starved either because the food was right next to them and there have been a few warmer days I think where they can break cluster to get to the food if they needed it.