The female Tawny Owl was in a horse chestnut tree just north of the Flower Walk, opposite the familiar California bay tree. She was not in a good place for a photograph when I saw her, and I couldn't find her mate or any of the owlets.

However, the Little Owl had come out on his usual tree to sunbathe, and was looking very fine.

We are hoping to see some little Little Owls quite soon, but no one knows when they started nesting, so we just have to keep watching.

A male Blackcap unexpectedly became visible in a bush on the path beside the Long Water near the fallen horse chestnut tree. He was leaping about briskly in the branches, uttering sharp chippy calls, and I was lucky to get a clear shot.

There are still a lot of recently arrived Great Crested Grebes in the middle of the Serpentine between the bridge and the island, but they are now splitting up into couples and challenging each other. This grebe was performing an unusual display.

Apart from their normal dance, grebes have a routine called the 'cat dance', in which one of the pair raises his or her wings to appear larger than usual, and the other stands up in the water and pirouettes in front of him or her. It is possible that the first bird is mimicking carrying a large load of chicks on his or her back, obviously an attractive display.

But in this case the grebe's partner was 50 yards away, and rapidly approaching. This posture, with wings raised much more than in the normal 'cat' posture, looks like a 'super cat' intended to be visible from a distance. I have never seen this before.

When the grebes came together, they went into their usual display ritual and did the usual dance -- though 'usual' is not the word for this wonderful spectacle.