Yet another Great Crested Grebe nest has appeared on the Long Water, on the east side a few yards from the bridge. This brings the total of nests currently occupied on both lakes up to seven, an unprecedented state of affairs for mid-August, and caused by the cold spring which made the fish spawn later and caused a food shortage for months. The new nest is too far away for a photograph, so here is a picture of the middle nest of the three closely spaced ones on the island.

The new Moorhen chicks on the Italian Garden pond were being fed both by their parents and by their older siblings.

When no one is trying to feed them they seem to be able to eat the plentiful algae themselves. But feeding them gives the rest of the family a bit of gratification.

The four young Mandarins are growing up, and are already beginning to look like their mother -- which they will for some time, even the males among them.

They were roaming carelessly around a wide area of the Serpentine neat the bridge, mixing with families of Coots, Mute Swans and Egyptian Geese. They seem to lead a charmed life.

I hadn't seen a Little Grebe for some time, and felt the lack of them. So I walked over to Regent's Park and found several swimming around the island. They bred here this year, but I didn't see any chicks. Little Grebes only bred on the Long Water once, in 2011, and soon lost their chicks to gulls, but for some reason Regent's Park is a much better habitat for them. I also saw a Tufted duckling here; there have not been any of those in our park for many years. But we do have more Great Crested Grebes than there are in Regent's Park, and their breeding success is greater.

There were quite a few House Martins over the Serpentine, more than I have seen for a while. I don't think they will yet be massing before migration, so it was probably their fledged young from the nests on the embassies that had increased their number. There were also plenty of House Martins in Regent's Park. These nest in the wooden eaves of the bay windows of Rossmore House, a tall 1930s block of flats on the corner of Park Road and Rossmore Road. Here is one of their nests.

This is a conventional cup-shaped nest, not like the nests in the plaster roses of the Knightsbridge embassies, which require much less mud to make. I have been told that Rossmore House was redecorated not long ago and the decorators removed the nests, but there are at least half a dozen in visible places, so the birds must have been busy rebuilding them.