Again there was a big crowd of House Martins over Kensington Gardens. They must be massing before migration, but they seem to be doing it quite gradually.

The Mute Swans on the Serpentine, having nothing better to do on a quiet afternoon, were enjoying a territorial fight. Several of them chased each other the full length of the lake. Here one of the parents of the seven cygnets repels an intruder.

The victim is being driven not on to the open lake, but into a corner at the end of the bridge, whose shadow can be seen at the top of the picture. This is a popular tactic, because if the swan can be pushed out of the water on to the shore and through the pedestrian tunnel under the bridge, it will be stuck on the land, as there are only two places on the Long Water where a swan can get down to the water and they are both a long way from the bridge. A few months ago Malcolm the wildlife officer had to come and rescue a swan that had been beached in this way.

The gulls were also bickering in their usual style. Here a Lesser Black-Backed Gull swoops nimbly into the water between two Black-Headed Gulls to seize a bit of bread that someone was throwing to a swan.

Here is an adolescent Wood Pigeon just beginning to grow its white collar. The white wing bars that distinguish one of these birds in flight were also beginning to show, but at this stage the mixture of new white and old grey feathers just registers as a slightly lighter grey stripe.

At first glance this is a very routine picture of a Grey Heron standing patient and motionless waiting for a fish to come into sight. But look what it is standing on, a thin cord.

It had absolutely no difficulty staying apparently stock still, though I am sure that its legs were making little motions of adjustment the whole time. Like many birds, it can sleep standing on one leg, but when a tall thin heron does this trick it looks particularly impressive.