I had to move 2 hives and then the weather turned unseasonably cold. I moved them on a night when low was 60s and the 2 weeks since it's been in the 30s and 40s and down as low as scant 20s. This was the first real cold spell this fall. There were some out today...it was the first day above 45. I checked around the hives and there are maybe a couple hundred dead bees by each. Is this normal? I am in SE Nebraska.