A mating flight (I think)

Glancing out of the window this morning I saw a lot of bees in the air.  At first I thought this was another swarm but it was coming from hive 4, which shouldn't be able to swarm as it was reduced to one sealed queen cell 10 days before.  I went over to watch and there were thousands of bees in the air - and on the hive roofs and nearby raspberry canes and cane supports.

Most of the bees were just sitting around while others flew about excitedly but there was no sign of them coalescing, as in a swarm.  There were a lot on the front of the hive and a clump under the landing board.

I guessed this was a mating flight but wasn't sure what stage it was at - whether this was the virgin queen leaving or returning.  I watched for about an hour, hoping I might see the queen return.  As I did so the fanning slowly subsided and the number of bees gradually diminished as they moved back inside.

It was cool (11℃), grey and breezy, perhaps not the best weather for a mating flight, but it has been worse recently.  I read since that mating flights last for between 5 and 30 minutes so my guess is that the queen was probably already back in the hive by the time I got there.  I'll wait another two or three weeks before checking that she is laying well.