The male Tawny Owl was also rain-spotted, but his plumage doesn't get wet in anything less than a hailstorm.
A pair of Great Crested Grebes were exploring a possible nest site under the willow tree on the Long Water near the bridge. But a young Mute Swan barged straight through the middle of the place and started eating algae off a submerged branch, so they had to wait till it had gone.
The spot that the grebes were eyeing was the bundle of thin twigs curving out of the water just this side of the swan. A floating nest could actually be founded on them, but it would not be a strong site. It was here that a pair built a nest last year and laid eggs, but then the nest was destroyed by the waves kicked up by a strong east wind blowing under the bridge. They would be wise to look elsewhere.
A young Herring Gull was playing with a plastic cup on the edge of the Serpentine. First it dragged it out of the water ...
... then it carried it up the sloping edge and dropped it, so that it rolled back into the lake.
The gull repeated this several times before it got bored and wandered off.