One adult Tawny Owl and one owlet were visible today -- but not to me. Des found them with his usual skill. I blundered around the Flower Walk twice and I am sure I was within a few feet of them, but couldn't see a feather. So it goes.

There were several House Martins over the Serpentine. I had seen three martins on the Round Pond yesterday, but too briefly to be able to identify them as House Martins. You have to see the white patch on their rump when they bank in a tight curve to be sure. With mild weather coming, plenty of flies to eat, and lots of mud for nest building, they should be well set up to start nesting on the French and Kuwaiti embassies in Knightsbridge.

Two pairs of Mute Swans are also building nests. Those on the Serpentine are probably the ones who had seven cygnets at the Lido last year -- they have rings, put on when they were sent on a compulsory holiday during the Olympics. They are building near last year's site at the Lido. The pair on the Long Water, after much deliberation, seem to have decided on a reed bed next to the Italian Garden, and were busy ripping out reeds to make their nest.

There are only two swans on the Long Water. The number on the Serpentine is falling as they fight each other and the losers are dismissed to the Round Pond.

There is also another Great Crested Grebes' nest on the Long Water, visible directly across the lake from the Peter Pan statue. In this picture they have been mating. There is only one way off for the top bird, over the mate's head and into the water with a splash.

Wonderfully graceful on water, grebes are hopelessly clumsy on the ground.

A pair of Wood Pigeons were billing and cooing on a branch near the Italian Gardens. There will be another large family trundling around on the grass soon.

Nearby a Greenfinch was singing his peculiar song, alternately twittering and wheezing.

No other bird has a song anything like this. For some years I couldn't work out where this extraordinary noise was coming from, as the birds usually sit near the tops of trees and are difficult to spot. This one was unusually low, in one of the small hawthorn trees between Peter Pan and the Italian Gardens.