A dismal chilly day with occasional flakes of snow didn't stop the Great Crested Grebes near the bridge from dancing.
At the east end of the Serpentine, the pair which had built a nest were not having good luck, as the site had been claimed by Coots.
You can see from the large twigs that the most recent work here has been done by them. The grebes are hanging around, and are quite capable of driving the invaders away, but they will return again and again and usually win these disputes. The grebes would be best advised to make another nest a bit farther along the reed bed when the weather gets milder.
One of the Peregrines was circling high over Kensington Gardens, too far away either to see which one it was -- females are considerably bigger than males -- or to photograph it.
There was a small flock of Greenfinches in a tree near the Diana memorial, but they would not come out for a picture either. They tend to perch high in trees, which is not much use when you are underneath trying to see through the branches.
The family of Moorhens from last year's nest in the Italian Garden pond has stayed in residence all winter. Here is one of last year's young, just developing adult colours with the beginnings of a red bill and yellow-green feet.
And here is a very faded Carrion Crow, one of a number of crows in the park with greyish feathers.
They are not typical leucistic birds with white patches, and I am not sure what has produced these pale feathers. It is always the wings that are affected, while the rest of the bird is a normal glossy black.
In your experience how much longer would you expect to see the grebes 'dancing', and do they tend to do this at particular times of the day eg. early or late?
ReplyDeleteGrebes don't have a fixed breeding season. They will court and dance and nest at any time they have enough to eat and the weather isn't actually freezing. The pair at the east end of the Serpentine, whose nest has just been taken by a Coot, nested in September last year and fledged one chick -- the latest in the year I have ever seen.
ReplyDeleteCould be progressive greying rather than leucism (with leucism, one would expect at least some white on the bird's head).
ReplyDeleteI was wondering about that too. It affects quite a lot of birds in the colony north of the Round Pond, and seems to affect only wings. Maybe all the birds with this oddity are related. Maybe it's something to do with the fast growth rate of remiges, the largest feathers on the bird, and melanin not being laid down fast enough.
DeleteIt's definitely heritable but I think it's more to do with the loss of
ReplyDeletepigment cells as the bird is ageing (although, oddly enough, this process can start when the bird is still a juvenile). I actually think these birds look rather attractive... I saw this jackdaw in West Sussex earlier this year: http://www.finepetportraits.co.uk/birdphotos/1jackdaw2013.jpg
Fascinating! :)
Yes, that's the kind of pattern that is normally associated with progressive greying: the effect is seen over most of the bird's feathers. It's the very limited nature of the greying in the park crows that I find puzzling.
DeleteIt seems that the Carrion crows (Corvus corone) may be cross breeding with their relatives, Hooded crows (Corvus cornix), producing color variations not normally seen in the wild.
ReplyDeletehttp://www.fotolibra.com/gallery/320877/carrion-crow-hooded-crow-hybrid/
I have now seen individual Carrion Crows which have had white patches on their wings in their first year become completely black the following year, so I'm pretty sure it's nutritional deficiency that is stopping the black pigment from being laid down fast enough when the young birds are growing. It's most noticeable in the park because the crows are living on junk food.
Delete