a couple days later

You need to call a beekeeper or the county agent to come get them and put them in a place where they can be safe and productive. This has happened to me in the past, and that is what I did and they were so happy I called them.

Yes! call the bee keepers in your area. The bees are swarming and have no where to go. Somewhere on the bush is the queen and the rest are just staying near her to protect her.

Sounds like a good idea to contact your county agent. At the very least they can probably give you the name of a local beekeeper who can answer this question and/or provide them with a new home/hive.

Thanks for the replies.

I'll try to find a beekeeper, however I have to ask seeing as they are not in the house structure or causing a nuisance (other than eating my roses) why wild bees would otherwise need relocating? There are plenty bee friendly plants around here, we have many Vitex so are used to bees, and plenty trees with a couple of vacant bird boxes and bushes. I've just never seen this behavior before.

There's only about half the bees today and there's very few petals left.

It might be too late now when mostly are gone, most likely, queen has left too, the ones you see are still there because of the queens pheromone. Most of the damage on your flower was done when the large swarm landed there,..they weren't after your flower, ..just a place to rest, scout bees searching the area for suitable indoor cavity, ..could be inside a wall, large birdhouse, like a duck house etc. but most likely this swarm was too small to settle somewhere on their own, a bee keeper could have saved them.

When they first converged on the bush 6 days ago I thought it might be because a storm was heading our way, strong winds and thunder etc. but when they were still there the next day.....
Didn't have much luck yesterday finding a bee keeper so I put an empty bird box next to the bud the bees are on and they appear to have moved in. I'll give them a day or two to see if they actually settle in there then I'll put a temporary cork in the entrance hole and relocate the box to a tree out back away from human traffic.
If they do well or become too large a swarm I shall call a professional service to move them.

Bees we like, wasps and hornets on the other hand.......

They will die. If that is a swarm it would be the smallest most pathetic thing I have ever seen. Just let them dwindle down. If u wanted to collect that they wouldn't last. Who knows somebody may have moved a domestic hive during the day and some forgets were left behind with no home. The remaining will stay clustered like that. Highly doubtful a queen is in the er e.

Foragers*

Swarms only stick around for 1-3 days. Scout bees will be looking for a permanent home in the meantime.