It was about 3 in the morning that I heard the otter go by, bumpity swish along the side nearest the bank, as they do when they're hunting the fish whose escape route is limited by the boat hull.
So I got my head torch and went out, in time to hear a great kerfuffle up by the swingbridge; a badger's furious yickering.
I wandered up there, and over on the other side two dark forms separated and went in opposite directions. One turned to look at me and showed its distinctive black and white face, before disappearing under the bridge.
So it seemed like a good incident to recreate in this picture, though I've set it at dawn, so there's more to see.