I've never seen this in my yard before. It looks like these drones were successful in getting their genes into the gene pool. The sight of this makes me cringe, but only a little bit. I thought I would share, since this is something you just don't see every day.
I have two hives in the back yard and both queens are already mated, so I'm wondering why I'm seeing these "lucky" drones. I have a few books about bees, but none of them go into great detail on bee sex. I thought a mating queen will mate until her spermatheca is completely full and that would last her for life. Correct me if I'm wrong, I know you will