strange absconding conditions
This is my first post. I live in Miami Fl and I have been keeping bees for about six years (still learning) I have had my current hive for about two years, but have come across a few problems. About a few weeks ago, after a beetle problem, my bees absconded, but they left behind brood and honey, which is not normal. I re-captured my bees and put them in another hive. After three weeks they seemed to be doing fine (although there numbers greatly decreased to about 12,000), laying eggs and collecting honey. Then, this afternoon, I discovered that they have left again to the same tree, this time only about 4,000 bees were there, and they once again left there brood. I was able to recapture them again, but I'm not sure if they are going to make it.
My question is, why are the leaving behind brood. I don't know why they left the second time, they had syrup and no beetles or other problems as far as I can tell. They have been in the same location for about 2 years.