The Great Crested Grebes nesting at the east end of the island do indeed have chicks. It is very hard to see what is going on in the darkness under the bushes, but here you can just see the stripy head and neck of a chick as it reaches up to take some food from a parent, I think its mother. The father can dimly be seen on the left with his wings raised, no doubt sheltering more chicks.
The nest on the east side of the Vista has four eggs in it. Here a parent is turning them over to keep them evenly warmed.
There seemed to be only one Common Tern on the lake. It perched on one of the posts at Peter Pan. All the other posts were occupied by various gulls and a couple of Cormorants. A Black-Headed Gull wanted a perch and thought it would be easy to knock a smaller bird off it, but the Tern wouldn't be moved and pecked at the gull as it hovered.
After several tries the gull gave up and flew away.
The male Little Owl was in his usual place on the chestnut tree.
There seemed to be some hope of finding a Tawny Owl, because a Great Spotted Woodpecker was perched on a tree next to the chestnut where the young owls generally go, and was scolding loudly.
But no one could find the owl. Maybe the woodpecker could see it, but we couldn't.
An odd squeaking call from inside one of the small boathouses turned out to be from a young Feral Pigeon sitting on a beam.
A shoal of small fish were swimming around in the Long Water near the Italian Garden. I was photographing them when suddenly there was a big splash and they scattered, some of them leaping into the air. I had no idea what had happened until I got home and looked at this picture, which shows a large fish snapping at them.
The details are not at all clear, but I think it must be a pike.
There is a clump of deadnettles (Lamium album) in the reed bed at the east end of the Serpentine -- plants that look very like stinging nettles but are harmless. Their small white flowers didn't attract many insects, but eventually a honeybee arrived and gave them an unenthusiastic once-over.