At the Tawny Owls' nest site, a Wren was yelling defiantly at a Magpie that had come near its nest.

In another Wrens' nest -- or probably several, because male Wrens have several mates -- on the path to the east of the Italian Garden, just level with the parapet, you can hear the cries of young birds and see the parents dashing around the bushes.

The Mute Swans from the Lido nest were on the south side of the Serpentine with their seven youngsters, who have grown noticeably in the past two weeks. Here their father sees off a pigeon that had come too close.

The seven young Egyptian Geese are also doing well and growing rapidly. But most of the north shore of the Serpentine, all the way from the bridge to the far end of the island, is now blocked off for the Olympics, and is a noisy wasteland of trucks and scaffolding. Huge concrete blocks are being laid around the area to exclude us, the public who are paying millions for the upkeep of the park and billions for this ugly political show.

The lake is now abnormally full of algae considering the relatively early time of year and the lowish average temperature. I am very worried that the Olympic management will panic and dump chlorine in it, smashing the ecosystem and sending the lake back to the barren state it was in when I first started coming to the park before 1950. Here a Grey Heron peers through the slime hoping to catch a glimpse of a fish.