It's spring time which means bees often swarm. They do this for a few reasons including because they've run out of room in their hive, their hive isn't doing well, or it's a bumper season and the conditions are great for them to set up a new home and colony.
If a bee swarm lands in your yard, on a tree or bush, or sets up on a post near your office or other area don't worry as they will probably move on in a day or so when they find proper shelter and a great new home to set up in.
Normally, honey bees in a swarm will not be aggressive as they are still looking for a home, rather than trying to defend one. So yes, they will probably move on in a few hours or days. If not, you can call a beekeeper to collect them. Our bee team are often out and about with our own bees so we don't offer this service, but if you call your local Amateur Beekeeping Association, you will get some great advice and hopefully find a local contact to come and collect them.
Here's the NSW Amateur Beekeeping Association's information and advice on what to do with swarms as well as contact details for local beekeeping clubs.
Hope that's of help so you know what to do next time you are lucky to have a swarm come for a visit.
PS: This picture is of Daryl with a recent huge swarm he caught.