Yet another three cygnets on the lake, from the Mute Swans' nest at the west end of the Serpentine island. That makes 18 in all, a record. The various broods are being taken round the edge of the lake at a safe distance from each other, and I didn't see any fighting. However, the father of the first brood of seven was taking a hard line with some teenage Egyptian geese that had strayed into his zone of influence.

The eight young Egyptian geese are still in good order. Here is the family eating algae in the middle of the increasingly scummy Serpentine.

The House Martins have now started building nests in the cornice of the French embassy, their original preferred place, as well as in the Kuwaiti embassy. I saw twelve birds attending to six nests, three in each building. They also fly over the bottom end of the Serpentine hunting for insects.

The female Tawny Owl could be seen with difficulty at the top of the nest tree.

Andrew Williamson, a professional photographer who spends a lot of time in the park, has kindly sent me some superb pictures to use on the blog. Here are two of young Long-Tailed Tits waiting for their parents to feed them. When a parent approaches, their eyelids, which are usually orange, flush red. I don't know whether this is because of excitement or a stimulus to their parents to give them food; it could be both at once.