I have been beekeeping for a few years now and noticed that one of my hives that I started from a five frame nuc this year in April are always super busy and often times have a bunch of bees on the outside of the hive at night. And when it is night and dark they go back in but I can see them all clusters on the bottom of the brood box. They don't seem To be bearding because it is only 65 degrees out. Any more experienced beekeepers know what going on. I live in central Oregon if that helps.