Reported that a pair of Greylag Geese on the Serpentine have five goslings. I couldn't find them myself, so a photograph will have to wait. Meanwhile, here are three hybrid geese -- Canada fathers, greylag mothers -- who have been going around in a little group. Although these hybrids' markings differ quite a lot, they always have grey feet, unlike either of their parents.

The female Mute Swan on the nest near the Lido was shuffling restlessly on her nest, with her mate in attendance. This may be a sign that the eggs are about to hatch. There seem to be three swans' nests on the island; certainly two are in full swing. Two males were threatening each other nearby. This has not been seen before; until a few years a single pair of swans ruled the whole lake, and chased off any swans that had the temerity to come down from the Round Pond.

I met some men ferrying bundles of brushwood across to the island. It is to be laid in the water to encourage the growth of microorganisms that are supposed to purify the water and discourage the growth of algae. The park authorities, having recklessly agreed to the Olympic triathlon being held in a totally unsuitable, shallow,  algae-prone lake at the worst possible time of year, are now in full panic. They have already dumped tons of a chemical substance called Phoslock in the water, which is supposed to mop up excess phosphates. But their work has probably been in vain, because the large grassy expanse of the Vista was foolishly spread with leafmould to fertilise the grass, and during the recent heavy rain when the land drains overflowed, water cascaded down directly into the lake carrying huge amounts of nutrients that will suit the algae just fine. Well, we shall see what happens.

There was no sign of any of the Tawny Owls, but a brief glimpse of the Little Owl in the sweet chestnut tree where I photographed him yesterday. While I was up at the owl tree I dropped a plastic bag of bird food and it was promptly carried off by a crow.

All round the lake there is loud song, especially from Blackcaps, with several Song Thrushes adding their voices as well as the usual Robins and Blackbirds, and Chaffinches and a few Greenfinches and Goldfinches. Great, Blue and Coal Tits are all flirting and chasing each other through the bushes. I saw a pair of Coal Tits courting, performing that curious wing vibration that I have seen larger tits doing but had never seen with this species.

At least 50 Swifts over the Serpentine, but only a handful of House Martins, and there was no sign of the latter in their usual nesting place at the French Embassy.