Two Willow Warblers were chasing each other through the trees on the east side of the Long Water. When they paused in the chase, or perched after catching an insect, only one of them was singing, so evidently they are a pair and not rivals. This is the male.

On the edge of the Serpentine a pair -- I think there is only one pair -- of Grey Wagtails were also running after each other, also picking up bugs on the way.

They are slightly less shy than Pied Wagtails (with the notable exception of the completely tame Pied Wagtail in Queensway, which will now come to some people's hand to be fed). If you are careful you can get quite close to them. When they are running along the lake edge, the trick is to get ahead of them, hold up the camera so that they don't get disturbed by the movement of your arm, and wait for them to arrive.

To complete the spring flirtation, a couple of Goldcrests were chasing each other through the bushes at the southeast corner of the bridge, where there is a yew tree that they like.

A flock of Goldfinches passed over the Serpentine Gallery, chattering loudly. You can hear a flock long before you see the birds thronging through the trees.

There are also Greenfinches singing all round the Long Water, as well as a few Chiffchaffs and a Blackcap.

The Egyptian Geese near Bluebird Boats still have their four young, but the pair on the Round Pond have lost one of theirs and are down to two. This is not a good place and they would have done much better on the Serpentine.

A few days ago, a reader asked me whether the male Great Crested Grebe on the nest under the willow tree near the bridge is the very dark one with almost no white on his face. The answer is yes. However, their nesting seems to have been interrupted. Someone had seen eggs in the nest and now there are none, the result of some raid. But they are staying near the nest and will start again when they have built up their energy. The grebes who nested a few yards away from them seem to have abandoned that nest, which was too close for the comfort of these territorial birds, and they have built another nest a bit farther away.

The Tawny Owl family was still visible in the usual two evergreen trees in the Flower Walk. Here is a bundle of three owlets well hidden in the leaves.