A pair of Great Tits are nesting an a box on the north side of the Vista nest to the Henry Moore sculpture, giving a good view of their activities. Both parents are bringing food to the nestlings, and leaving the nest carrying a 'faecal sac' -- the young birds produce their excrement conveniently wrapped in a membrane, which keeps the nest clean. Here one of the parents arrives holding a caterpillar. Although this picture was taken at 1/1600 second, the wings are still blurred, which shows how fast they move.

And here is an odd shot. Small birds such as tits fly with what is known as 'bounding flight', in which they fold their wings completely for a moment and just shoot through the air like a bullet. Despite the height they lose at this time, apparently it is a more energy-saving method than flapping continuously. This tit is approaching the box where it will have to deploy wings and tail at full stretch sideways on to brake, but it still has a moment for a complete fold.

The Starlings nesting in the plane trees next to the small boathouses -- there are at least three nests here -- were also bringing food to their nestlings. Again, both parents were fetching food. Here one of them arrives at the nest hole with a worm.

Starlings don't use bounding flight. They glide between bouts of flapping, neatly and efficiently. I think they are the smallest birds that are able to glide -- perhaps not surprisingly, considering that they are the most skilled flyers among birds of this small-to-medium size.

And I don't know what this bird is.

It was sitting on the railings on the edge of the play area of the Lido, and when I took this hasty shot I thought it was a Dunnock, because this is a favourite perch for the pair that live here. But when I got home and looked at the pictures, it had none of the characteristic streaky plumage, and looked more like some kind of warbler. The colour of its plumage is bleached out by direct sunlight, so it is hard to see the markings. It doesn't seem to be a Chiffchaff, because they have dark legs, or a Willow Warbler, because they have brownish legs, or a Sedge Warbler (although they have pink legs) because its markings are too pale, or a Reed Warbler because its beak is too short. Can any reader identify it? This is the clearest of the few shots I was able to take before it flew away, so it's all the evidence I can provide.

There were still a reasonable number of Swifts and some House Martins, bit I saw just one Swallow over the Serpentine.

The Great Crested Grebe's nest outside the net to the west of the Lido, which had been deserted, seems to be occupied again, and the male was sitting on it in a determined way which suggested that there were eggs in it. It is in a dreadfully vulnerable place, exposed to the oars of careless rowers. But nests have survived in worse places, so there is always hope.