Hello All, I have been keeping bees for about 9 years now. Due to moving to Pennsylvania from Rhode Island and the birth of a son, my hives have been sitting empty for about 2 1/2 years. Last spring I started over with packaged bees and queens, just two hives. Both hives seemed to be doing fine, I had to feed syrup until they got things going on their own. Checking the hives regularly everything appeared to be normal. Comb was being drawn pollen was coming in the young queens were starting to lay. The bee inspector for my area of Pennsylvania came by checked the hives found 1 mite on a drone in one hive only. Very happy about that. Now. Both hives were cared for in the same way fed the same syrup. Both hives were at about the same stages of building and egg laying. I left the hives alone for about 2 weeks. Went down to check them and one hive was empty. No bees, no dead bees, nothing. This was a full size hive body with 10 frames, lots of room. The hives had not been disturbed by anyone or anything. So where did my bees go? I would guess that they swarmed or were taken by a UFO. Swarming seems more likely. Why would they swarm with room to expand within the hive? I have never had a swarm even when I was a bit behind in getting a new body on a over flowing hive. I usally go with a two body hive and add a third or fourth as needed for my honey when the hives are up to a good population, 60,00 - 80,00 or so. If anyone could answer why the bees would swarm under the above conditions I would like to hear what I might have done wrong. Thank you for your time. Gary C. Lewis Duke Center, Pa, U.S.of A.