I only recently learned about the Swan Upping Ceremony when I was looking on the internet for something both British and silly that could somehow cause Lord Nelson to lose an arm.
There are lots of traditions involving royalty eating swans and claiming all unmarked mute swans for their dinners. Somehow, the Vintners and Dyers got in on it as well and now, every year, a swan census is taken.
Apparently there are non-ceremonial positions, like the Queen’s Swan Marker, that are responsible for swan awareness and clearing the swans off of the Thames for regattas.
I hope the jaunty cap with the swan feather in it is part of his official uniform.
–Geoff