A pair of Jackdaws are nesting in a hole in an oak tree 20 yards from the southeast corner of the leaf yard.
I had thought they were up to something here, but this is the first time I have seen one carrying twigs into the hole.
The Great Crested Grebes' nest at the east end of the island has been occupied continuously for several days, and it looks as if they are serious about it.
A Grey Heron was also sitting, rather than standing, in the lowest of the nests on the island.
But their on-off nesting behaviour makes it hard to tell whether this nest is a going concern. I did see two herons in it recently, an encouraging sign.
Coots have also begun to nest. But this lot on the Serpentine were just fighting.
The Black Swan came sailing over to be given a biscuit. His girlfriend wasn't with him.
He looked peaceful and innocent, but I had previously met Marie Gill, who told me that he had charged a couple of Mute Swans doing their courtship display and blasted right through between them. It is not the first time he has objected to this display.
You don't see many Herring Gulls with rings, as most gull ringers concentrate on Black-Headed Gulls, which are easy to catch and very long lived, and have interesting migration habits. I looked up this ring, X3TT, and it's only from somewhere on the Thames, and the gull is less than a year old, so it hasn't travelled far.
The Redwings were at the top of Buck Hill again. They are much easier to photograph here than on the Parade Ground.
The male Little Owl in the chestnut tree near the leaf yard came out in the warm sunshine.
So did one of the owls in the lime tree on Buck Hill.
We don't know which of these owls is which, but this one looks quite big and is probably female -- with owls, as with hawks and falcons, the female is larger.
A Wren on the grass beside the Henry Moore sculpture had caught a midge.
At the far side of the grassy square a squirrel startled a rabbit by running behind it.