Firstly welcome to the Forum !
Secondly, have you found my article about Tree Bumblebees which is located in the About Bees part of this website.
Here’s a quick link:
It might help you work out what to do, but if not, please come back here and we can try to help further.
Thank you Clive.. that is very helpful
I see its just the larger drones mating.. quite funny as i stood about 4 foot away and watched them for about half an hour and they did everything you describe right down to the two bees coming together and dropping to the floor with a thud Clearly the other nest does not have a swarm as yet as the colony is not far enough along.
We will make an effort to keep that part of the garden out of use as much as possible so not to bother them too much and let them go about their business. Ive tried to make my garden as bee friendly as possible these past 14 years as so much harm is being done to them through pesticides etc.. Clearly ive hit the Bee Jackpot and got it just right haha
Thank you for your help.