Who is the king of the castle?

I am quite keen to recognise individually the wool-carder bees in my garden, especially the males. I think I will be able to understand better what is going on if I can tell who is who. Individuals appear to show quite a lot of variability in the yellow and black markings in the face and abdomen, so that looked promising. In their normal behaviour, the bees are quite fast and unlikely to pose for a frontal shot! However, in colder weather, or at the end of the day the bees are more restive, and often cling to flowers with their jaws. Today I had a chance to take a few portraits of the Wool-Carder bees. It was overcast most of the day and the temperature was around 16-16.5 oC. There was some storms yesterday and the male in charge was looking quite miserable with his hair soaking wet, clinging to the top of a Stachys spike.  Bombus terrestris and B. pascuorum bumblebees were happily feeding around him in the Stachys as if he wasn't there.

Bombus terrestris feeding close to cold male Wool Carder bee

B. pascuorum about to land on the same spike of flowers where the male is resting 

He shook his wings every now and then but was very still. I took quite a few close ups, of his face and abdominal markings. Later on I noticed there were also two females resting - or waiting for warmer weather - nearby. In the middle of the day they all seemed to arouse themselves a ilttle and they started to walk up and down the Stachys spikes feeding, but seemingly unable to fly.
 From the shots (comparing today's with individuals from previous years) it appears that the females have browner faces, and that it is possible that I will be able to see if the top male is overtaken by another later in the summer, most likely through the more visible and variable abdominal markings.

Male abdominal patterns. On the right is this year's male.

Female facial patterns

Male facial patterns. On the left our cold and wet friend