Black-headed Gull in Ground Effect

More movement in large ("L").

I managed to escape from town for a moment this afternoon. I ambled around Christ Church Meadow to see what I could see: it was cold and grey and I found no geese (alas), but I did find mallards, black-headed gulls, and lots of fungi!
I found myself drawn to this one, presumably because I've been hypnotised by my project and this is relevant... This gull is flying in ground effect (within a wingspan of a surface), which is one of the things that I am writing about (and have measured) for my project.

I've uploaded other shots from my walk to Flickr (right from this scratching mallard).
Highlights:
Juvenile black-headed gull squawking (in flight)
Painted mallard
Prankster black-headed gull (surprising a conspecific): 1 and 2
Misty dreaming spires [= blip alternative]
Fungi: bracket, little mushroom, large mushrooms
Mallard (m) and pretty ripples