I thought that the young Grey Wagtails had returned to their main colony at the old coal wharf near Chelsea Bridge, but there was one today beside the little pool at the top of the Dell waterfall.

The male Little Owl was in the nest tree.

A Carrion Crow perched on the enormous horse's head of the Physical Energy statue.

Another had a dogfight with a young Herring Gull on the Long Water.

A young Herring Gull, front, and a young Lesser Black-Backed Gull. At this age it's hard to tell them apart, but Lesser Black-Backs are slightly smaller and more delicate and usually darker. The only reliable way is when they spread their wings and you can see the paler inner primaries of the Herring Gull, whereas the flight feathers of a Lesser Black-Back are dark all along.

The fourth pigeon-killing gull on the lake is one of three Lesser Black-Backs of whom the first is the notorious gull who has been at it for years. The other killer is a Herring Gull.

All three young Grey Herons from the third nest on the island are now climbing around in the trees.

The two chicks of the Great Crested Grebes at the west end of the island are growing larger daily.

So is the single Coot chick in the Italian Garden.

A Pochard seemed to have temporarily evicted a Coot from its nest on the Long Water.

A Red-Crested Pochard drake in eclipse browsed on the algae. In this state his plumage is exactly like that of a female but, unlike her, he has a red bill and eyes. Females have brown eyes and a brownish beak with a tinge of pink at the edges.

It would have been interesting to see how this snail managed to climb from the vertical bar of the railings around the angle to the horizontal strip.

A Common Drone Fly, Eristalis tenax, perched on a rose leaf. Like the Honeybee it mimics, the species has light and dark forms.

Mark Williams sent three good pictures. A Painted Lady butterfly, now a bit tattered, posed on a Meadowsweet flower head in Kensington Gardens.

Willow Emerald damselflies mated in St James's Park.

And there were plenty of Chiffchaffs at the Welsh Harp reservoir, which he reports is an excellent place for seeing many kinds of warbler.