The Great Crested Grebes nesting in the poplar tree on the Long Water have left their nest. They were carrying their chicks about on the open water yesterday, and have now disappeared entirely and are probably lurking under the safety of a bush. Today the nest has been taken over by Coots, and already has that solid twiggy look that Coots' nests have.

It is not unusual for grebes to leave an exposed nest site as soon as they can. In 2004 a pair nested in an even less suitable place, on the chain crossing the Serpentine next to the bridge. Their first nest was washed away by a storm -- this was the same storm that flooded the Diana memorial fountain almost as soon as it opened. So the grebes built again in the same place, in mid-July, and laid five eggs. It was a very hot summer, and they were uncomfortable; they changed places on the nest every ten minutes instead of half-hourly as usual. Within hours of the last egg hatching the birds packed their babies on their backs and went to shelter under the bridge. All five chicks survived and fledged.

The Cormorants are slowly returning. Sometimes you see as many as four together in a fishing gang, diving in their peculiarly inelegant way.

The fish they catch are only 3 inches long at the most, smaller than they would like, but now numerous enough to retain their interest.

There is a constant noise of scolding from Jays and Blackbirds in the leaf yard. I think it is because the Little Owls have taken up residence there, but it is impossible to see anything. The place is now a complete jungle of 8 ft high nettles interspersed with thistles, whose purple flowers make an attractive contrast with the yellow of the oilseed rape that is also beginning to establish itself.

There are also a lot of young Blackbirds all over the park. Roy Sanderson's survey of Blackbirds carried out last spring showed only 18 territories in Kensington Gardens, but numbers were boosted by the arrival of a lot of adults the following winter, and they have stayed and bred. It would be interesting to carry out the same survey next spring, but I don't think there are enough regular bird counters left to do it; there were never many and one has given up.

Near the southwest corner of the 'Bird Sanctuary' (the shrubbery around the Hyde Park greenhouses) there is a large family of Wrens, easily visible in the open scrub and, as usual, very noisy.

The deserted landing stage of Bluebird Boats, shut down for the duration of the Olympics, has become a place for Grey Herons to stand.