Tuesday 20 November 2012

Both families of Great Crested Grebes have left the Long Water in the last few days, and I think the childless couple went with them. All their young had long been able to fly. Maybe they left because the Cormorants had eaten their way through most of the medium-sized fish. Maybe they sensed that the weather was getting colder, and left to avoid being frozen in -- this can be a bad problem for Great Crested Grebes with their need for a 50 yard take-off run, and they are wary of the threat of ice. They don't migrate, they just move around to what they consider suitable places.

It is not clear where they go when they leave the lake, but I think it is probably the Thames somewhere upstream of Chiswick, where the current prevents the water from freezing and there are plenty of weedy backwaters where they can hang around without having to constantly swim against the strong current. In very severe weather they have been known to go to sea, where they can live perfectly well. Their ability to live in salt water explains why Great Crested Grebes are found all over the temperate zone of the Old World; they have even reached New Zealand.

The Little Grebe, a less seaworthy bird, is found only as far as 'Wallace's Line', the big gap in the East Indies to the east of Borneo that divides Asian and Australasian species. East of the line it is replaced by a near relative, the Australasian Grebe Tachybaptus novaehollandiae, which looks very similar but has yellow eyes.

Anyway, the Great Crested Grebes have given us a fine show this year, and there are still some on the Serpentine.

Speaking of birds looking ruffled, here is a female Egyptian Goose who was caught by a sudden gust while preening herself.

A Wood Pigeon struggles to keep its balance while reaching for a berry.

They flap heavily in and out of the bushes, constantly beating their wings against the twigs. It is surprising that their feathers aren't in shreds.

And here is a Grey Wagtail coming down to the water's edge in its perennial search for small insects.

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