Bees attack drone

Was filming in Koonung Creek Reserve in North Balwyn at about 50-60 metres off the ground. Some of the local bees didn't like that.
It took me a minute or two to notice the bees in my screen. As you can see in the first shot, they were only on one side of the drone to begin with. Once I realised, I brought it down as quickly as possible which I figured was the best thing to do.
The drone was fine afterwards, no permanent damage. Did take a while to clean though.

[@g_e_o_m9369]

One of three possible outcomes:
a) A passing swarm met your drone in the same airspace
b) In the open space you just happened to fly into a mating circle where drones (male bees) congregate from multiple hives to await virgin queens for mating
c) There is a wild hive in a tree nearby and the sound of the props was enough to annoy enough of the bees to come out and start something.
As best I can tell from the footage there appears to be drone bees in the frame (rounded abdomens - they don't have a stinger like females do) so possibly you got a one in a million shot and flew into a matting circle.
And if it was B like I think it was don't feel bad, males die immediately on mating, their genitals explode on climax.