The Great Crested Grebes' nest on the Serpentine isalnd is hatching out again. It's very hard to see what's going on through binoculars, and well nigh impossible to photograph. Let's hope these birds have better luck this time. There are fewer Grey Herons than there were when they lost their first brood, and the heron nest close to theirs has been abandoned.

Andrew reports that he heard one of the Little Owls calling yesterday, from the chestnut trees where they were in April. He couldn't see it, hardly surprising as he was looking for a small, perfectly camouflaged bird in dense foliage.

Speaking of perfect camouflage, spot the Treecreeper in this picture.

A Mallard on the Long Water has five ducklings. She was keeping them well into the side of the lake under the bushes as a Lesser Black-Backed Gull flew up the lake.

The Magpies near Rudolf Steiner's bench overlooking the Long Water from Buck Hill are constantly chased by two noisy youngsters clamouring for food.

I met Roy Sanderson negotiating the enormous detour around the Olympic building site. He had been counting House Martins' nests on the French and Kuwaiti embassies, and brought the welcome news that the birds have started recolonising the French embassy. He saw five pairs of birds attending nests, two on the French embassy, three on the Kuwaiti building. I went there later and saw four nests being attended to on the Kuwaiti side, and one on the French side. It is very difficult counting active nests, as a pair of birds may go away and hunt over the lake for a while, and not be counted. There are six nests on the Kuwaiti embassy, but they were built in previous years and may not all be occupied.

Here a Canada Goose flaps its very tatty wings, but you can see the blue wrappings of its emerging primary feathers.