Being stuck under a tree in the rain has its compensations. Sheltering from a heavy shower on Buck Hill, I watched a Mistle Thrush poking around in the grass.

Suddenly there was the mechanical whirring sound of a flock of Mistle Thrushes, and two dozen of them passed overhead. The single bird flew up to join them.

It started to rain hard again as I went past the Serpentine Gallery, and I took refuge under another tree. This time the entertainment was a large band of House Martins, about 80 of them, more than I have ever seen in the park at one time. They whirled around twittering at treetop height. Perhaps they were the colony from Rossmore House at the southwest corner of Regent's Park joining the local birds from the Kuwaiti embassy to begin the long journey to Africa. I tried unsuccessfully to photograph them in the rain.

Several flocks of Long-Tailed Tits went past in various parts of the park, looking like exclamation marks flying dot first on their erratic course from tree to tree. Their numbers are increasing, a welcome development as the sight and sound of these tiny birds lifts the spirits on the dreariest day.

The Cormorant whose odd behaviour with a leafy twig I noted a few days ago has taken up a permanent station on the fallen horse chestnut tree on the Long Water.

 A red maple leaf announces the arrival of autumn.