Today, I decided to check one of my hives that I suspect swarmed a few weeks back. Last I checked, it was filled with capped and open brood, but I never saw any queen cells or the current queen. There was lots of nectar and honey, and a metric ton of bees.
This time, the hive was filled with nectar and honey, had a few capped drone cells and a small patch of capped worker brood (very small) and was stuffed with at least 2-3 capped queen cells on every brood frame (there were three as I had opened the brood nest two weeks back). While I was working the hive, I heard a loud buzzing and saw bees flying around overhead in the tree above the hives. They congealed into a small swarm hanging from a branch.
I noticed a flurry of what appeared to be robbing type behaviour from one of my currently queenless hives, but other than that I am not sure where the swarm came from. Do hives swarm when being worked? I did not notice any unusual activity other than the typical head-butters circling my veil. These queen cells were already leathery and capped, but not bald on the end. They looked very much like supercedure type queen cells. I split the brood frames up with my queenless hive and started another nuc with the others. I left one in the hive as I suspect they definitely have no queen now.
Has anyone ever had a hive swarm while they worked it?