Here you see the white facial hair. I expect all the hairs help it to keep warm while it's waiting around.
This one is checking a nest hole in the wall.
This one is investigating a nail hole in a post in the kitchen garden which definitely doesn't contain female bees.
As well as patrolling the garden looking for females they have to feed themselves. These two are taking nectar from broccoli flowers. You can see they are carrying a few mites.
This one has quite a lot of Chaetodactylus mites on his back. I read on Ed Phillips' Flickr page that the mites do no direct harm to the bee but jumped onto his back as he emerged and are hitching a ride to the bee's nest where they will lay their own eggs.
This guy is having a good scratch with his middle leg - I expect the mites are itchy.
This little beast has also been lying in wait for the female mason bees. It is Cacoxenus indagator, a parasitic fly that plans to lay its own eggs in the mason bee nest where they will hatch and eat the food intended for the bee larvae. Its motto is "Why do something yourself when you can get someone else to do it for you?".
The female red mason bees should be out any day now. I'll post some pictures when they are.