Robin climbing a tree

A Robin was climbing up the trunk of a tree near the bridge, not something you often see them doing. But it was clear what the attraction was when it pulled a beetle out of a crack in the bark.

A Long-Tailed Tit perched for a moment in a treetop beside the Long Water.

A Rose-Ringed Parakeet was eating unripe arbutus fruit from a tree in the Dell. They are messy and wasteful feeders and drop more than they actually eat, which often results in a tree being completely stripped to no good purpose.

They are particularly font of catalpa beans, which they strip out of the long pods.

The female Little Owl at the Round Pond was in her usual place in the horse chestnut tree.

But of course when you think they've got a fixed habit they suddenly change it, which is what the owls at the Serpentine Gallery did and I can't find them now.

However, the Peregrines have been using the barracks tower for years, always as a day perch for eating pigeons, and they spend nights somewhere else. They have a second day station on the tower of the Metropole Hilton hotel in the Edgware Road and, to judge from early morning reports by Des McKenzie, they must roost somewhere in this area.

A Lesser Black-Backed Gull with unusual pinkish-grey feet was finishing the remains of one of the famous gull's pigeons.

The killer had had enough to eat and was resting on the Dell restaurant roof. He couldn't be bothered to fly down and chase it away, but he called irritably.

Black-Headed Gulls hovered beside the Serpentine hoping to catch a bit of bread thrown up in the air.

A Grey Heron on the shore had also received a donation, a large fish head. It flew off and I didn't see whether it managed to swallow this awkward lump.

The two Great Crested Grebe chicks from the island were fishing busily at the Lido but not yet catching much, if anything. Their parents are still dutifully feeding them.

The single chick from the east end of the island is much younger and still quite small.

A Greylag Goose at the Lido held a conker. I don't think it could have eaten it.

A Common Carder Bee emerged from a bindweed flower near the bridge.

At the back of the loggia in the Italian Garden there are three curious stone humps in the ground.

If you go to the other side of the wall you can see that they are the tops of vaults leading to the three arches where the Westbourne river used to flow into the Serpentine before the Italian Garden was built in 1860 and the smelly river diverted to avoid fouling the lake.

This is what it looked like in the mid-19th century. The arches are unnecessarily large for such a little river, but no doubt they were designed for a grand effect when the Long Water and Serpentine were created between 1727 and 1731 by damming the river. A neo-Gothic style was chosen, with knapped flint walls to create a rustic effect.

The fountain could not possibly have been driven by the Westbourne, never more than a small stream and flowing in a ventilated gully so there was no opportunity to build up a head of water. However, there is a spring on Buck Hill with quite a powerful flow -- you can still see this through a vent some way up the hill -- and I think this was enclosed in a pipe from below the vent so that the water came in with enough pressure to drive the fountain.