There are times when you think a bird might be in trouble, but you don't know. This Great Crested Grebe on the Long Water, on the west side of the Vista, was in a small patch of water 10 ft square, surrounded by ice, about 100 yards from the nearest open water by the bridge.

It couldn't fly out, because these grebes need a long takeoff run to get airborne. But it was able to catch fish where it was. And although grebes are extremely bad at walking on their highly adapted legs, I have seen one actually running for an equal distance across ice to reach clear water. But did this bird remember that there was clear water nearby? And was it too desperate to take sensible action? Tonight's frost would reduce the size of its clear patch. When I saw it swimming up and down restlessly, I rang Malcolm the Royal Parks Wildlife Officer, and left it to him to decide if it needed rescuing. It would be well nigh impossible to catch, but he could ask the people at Bluebird boats to send up one of their motor boats tomorrow to break a clear passage through the ice and allow it to escape. They already do icebreaking duty on the Serpentine.

Here, at the Serpentine island, is a pair of Great Crested Grebes one of whom is in summer breeding plumage, and the other still in monochrome winter plumage.

Despite (or perhaps because of) being increasingly hemmed in by ice, they were having a lively territorial dispute with the pair next door. This area between the island and the shore always remains clear in freezing weather, because it gets full of geese and ducks that keep the water moving.

The Bearded Tits are still in their reed bed. The human excitement has died down a bit, and when I came past in mid-afternoon there was no one watching them except me. I felt that I was having a privileged private view of these beautiful little birds.

The pair of Moorhens who roost and nest in the willow tree near the bridge were undisturbed by their tree being covered with snow, and were strolling nonchalantly down the sloping trunk to forage for food on the shore.