The Ring-Necked Parakeets have returned from their summer holiday in the fields, and are as keen as ever for peanuts. Unlike other birds, they seem to prefer peanuts to the more expensive kinds. Perhaps they find shelling them amusing.

The Mute Swans from the Lido came to the shore next to the Peter Pan statue to be fed. The lone male swan who lives on the Long Water, who lost his mate and his nest, probably to a fox, resented this intrusion. Here he is approaching in the background, and the male of the pair, on the right with wings half raised in threat, is heading out to confront him.

They had a long bout of circling each other threatingly, but did not come to blows. Meanwhile, a Grey Heron thought it would fun to buzz them.

Eventually the dispute was settled. The Lido swans now rule the territory on the right side of the line of posts, and the lone swan has the territory on the left. But any crossing of the line will bring trouble.

I saw two Reed Warblers at the patch of reeds on the Long Water next to the bridge. One flew down from a tree and vanished into the reeds, and then I heard faint calls in what sounded like a Reed Warbler's scratchy voice from the tree. It could have been a young Great Tit calling for food; I was not sure. So I looked up into the branches, and got a momentary but clear glimpse of a Reed Warbler moving around in the twigs, I suppose looking for insects.

A pair of Coots has built a nest inside the outflow of the Serpentine. There is a large filter bed behind the balustrade, under the path. I heard young Coots calling plaintively from inside, while a pair of adults stood on the weir, over which water was flowing briskly.

I hope the young birds can get out. In previous years a Coots' nest here has failed, and a Moorhen's nest has succeeded; but young Moorhens are more agile than Coots and better able to jump up the weir.

Roy Sanderson has looked at the picture of the ring on the leg of a Black-Headed Gull that I put on the blog on the 18th. He has changed his mind about it, and think it may be one of his. He writes:

'It is a British ring. The "NW" is actually part of www , the web site address of the BTO [British Trust for Ornithology]. In quite small letters above that is part of "museum", the address to send the ring number to. The ring number is possibly EX 6369x, the x being a missing number; EX is a guess. That series of ten EX numbers was used by me in December 2011, all in Hyde Park. 63693 was seen in Bushy Park and 63694 in Regent's Park before they left for their breeding sites, probably in the Netherlands or Scandinavia.'

It shows how much information you can get from a ring, even when it's a guess at a partial number.

The Great Crested Grebes nesting on the Long Water were calling excitedly to each other and displaying their crests. I could see no reason for this, but it is possible that their eggs are beginning to hatch. It's a pity that this spectacle happens at such a distance, which makes a good photograph impossible.

The grebe family on the Serpentine were also rushing around, and both chicks were being fed by their father. He was catching a small fish every time he dived, about twice a minute, so there is now no shortage of food for the young. He was clearly getting bored with his solitary labour, and stopped from time to time to call his mate, with the 'aaaAAAaaa' call that in the language of Great Crested Grebes means 'Come here.' But she was nowhere to be seen.

On the Long Water, one of the male Red Crested Pochards in eclipse came over with his mate. As you can see, they now have almost exactly the same plumage, and you can only tell the male by his bright red bill. He will be regrowing his usual showy plumage quite soon.

Opposite the Peter Pan statue, a Grey Heron stood indifferently in a line of Black-Headed Gulls, some of which were playing their usual game of knocking each other off the fence posts. I don't know whether this is caused by high-ranking birds pushing the lower-ranking ones away, or whether it is just a general display of aggression.

The young Egyptian Geese at the Round Pond are trying their new wings, flapping across the water trying to get airborne. None of them managed it while I was there. It is a poignant moment, because seven of the ten will be able to fly and three, which suffer from the 'angel wing' deformity, will not, and don't have much of a life to look forward to. Here one of the unlucky ones thrashes desperately to no avail.

I went up to the place where the sighting of the Red-Breasted Flycatcher was reported. No result, but it is an interesting area. There are more Blackbirds here than anywhere else in Kensington Gardens, where the population has fallen severely in recent years. They are mostly at the extreme northern edge of the park by the Bayswater Road, where the park is bounded by a holly hedge that they like -- they don't seem to be disturbed by the traffic only feet awat. I think they roost and nest in the gardens of the houses in the side streets, and fly into the park by day to find worms in the grass. There was a young Blackbird among them, with speckled juvenile plumage, following its mother and calling for food.

The avenue of lime trees parallel to the edge of the park is a good place to see Long-Tailed Tits, which move along it in flocks looking for aphids.

(If you park your car under a lime tree, the aphids will cover it with their sticky secretions, which are hard to remove.)

On the Long Water, some of the Mallard ducklings have reached a fair size.

The posts are now covered with returning Black-Headed Gulls, gradually losing the chocolate brown head feathers of their breeding plumage. In winter they will have white heads with a dark spot around the ear.

Here a Green Darner dragonfly rests on the tarmac at the edge of the Serpentine. It was remarkably calm about being photographed, and this shot was taken at a distance of six inches.

Another fruitless search for the Red-Breasted Flycatcher. Roy Sanderson came up from Sussex in the hope of finding it, and we wandered around the area without seeing or hearing anything. It may well have moved on. The fleeting glimpses on Sunday and Monday are, sadly, not enough to claim it as a definite sighting, so it can't be added to the list of 194 species seen in the park given in the right column here. Well, you can't expect birds to turn up to order.

On a showery day, there was nothing unusual to be seen. The familiar families were in their places and, at the Vista where people were feeding the waterfowl, there were seven Mute Swan cygnets being circled warily by two broods of Mallard ducklings, and a few young Coots and Moorhens, all accompanied by their parents. For the smaller birds, getting too close to a swan can be dangerous. But there are also squabbles among families of the same species: here some Mallard ducklings are chased away by the mother of another brood.

On the Serpentine, an almost fully grown young Moorhen made an appearance from somewhere. You can never quite tell what is going on with these modest and secretive birds.

Andrew Williamson sent me this fine picture of a Black-Headed Gull screaming in derision at something, as they do.

On the original large photograph, you can read the near side of its ring.

The top row, too small to see here, is the ringer's address. The middle row has three letters: [illegible], N?, W. The bottom row has four digits of a number; since it begins at the join in the ring, visible on the right, it is 9????636. I showed this information to Roy, who said that it reveals enough to show that the bird was not ringed in Britain. English rings have markings starting with E and another letter; it started with EA and is now up to EY.

If you manage to see a ring number, especially on a gull and especially if you can read all or most of it, Roy would be most interested and may be able to tell you where the ring is from. Just put a comment on this blog.

Another frustrating search for the Red-Breasted Flycatcher. It is not an easy place to see, since the trees in which it was found are surrounded by bushes, and it is very close to the noisy Bayswater Road. I though I heard a snatch of song through the roar of the traffic, and waited for more, but that was the last I heard. Will keep trying.

Returning to more ordinary birds, the male ducks of several species are in full eclipse, and can only be told from females by the colour of their bills. Here is a male Mandarin,

and a male Red Crested Pochard, whose striking red bill stands out sharply from his drab beige plumage. Sorry about the poor photograph, but it would not come near enough for a good shot.

This Mallard drake, the mate of the black and white duck illustrated a while ago, has also become almost monochrome himself. Here he preens his wings, where you can see the new primary and secondary feathers growing.

It is going to be a better year for Mallards than previous years. Several broods are now grown to the point where they are reasonably safe from Lesser Black-Backed Gulls, and have only the ordinary dangers to face on their way to adulthood. It is remarkable how the big gulls are staying on the Serpentine and hardly going to the Long Water at all.

This young Robin has just grown his first red feather.

Yes, we do have a Red-Breasted Flycatcher. My friends Malcolm and Ko, who had seen the mysterious bird yesterday, listened to recordings of its song and went back to the same place this morning to make sure of the identification. It was a little to the west of where they had found it yesterday, still near the Bayswater Road but opposite the Lancasters, that newly done-up Victorian terrace.

I went there a bit later and the bird had gone back to the Forsyth memorial, and was singing intermittently in the dense bushes. I didn't manage to see it, but the song is unmistakable. Here is a YouTube clip showing a Red-Breasted Flycatcher singing. What a pleasing bird to find at a slow time of year.

The Great Crested Grebes from the Serpentine island had brought their chicks out to near the Bluebird boat hire jetty, and were busy feeding them, finding quite a lot of fish of a suitable size.

One of the chicks got too pushy, and was chased off.

But of course its parent relented and carried on catching food for it. The young birds have reached the stage where they look underwater and dive to follow their parents. They will follow them more and more closely on their fishing expeditions, and in this way will learn to hunt themselves.

A pair of Coots have built a nest on the east side of the Vista, using a fallen branch as a support. Here one of the parents carefully turns over the eggs to make sure that they are kept evenly warmed.

Beside the Serpentine, one of the blond Greylag Geese was carefully preening its elegantly pale new wing feathers.

Some park friends of mine were excited at seeing a mysterious small bird which they couldn't identify. It was in the memorial to the naturalist William Forsyth on the north edge of Kensington Gardens, where clumps of forsythia (named after him) are planted. They said it was the size of a flycatcher -- that is, about the same size as a Great Tit -- and dark brown with an orange patch high up on its breast, almost like a collar, and that it was singing loudly and volubly almost like a Nightingale.

There is a Red-Breasted Flycatcher that fits the physical description, but its song is too quiet and short to fit the one they heard. Another possibility is a Common Redstart, whose song is more similar, but this has a red tail and they were pretty sure that this bird didn't. So, at least for the time being, it remains a mystery.

I went up there and heard a Wren singing,

and saw a flash of brown and orange in the grass but it was just an unusually ginger female Blackbird.

Will keep looking.

The Moorhens nesting in the Italian Garden have four eggs. This is not a secure nest site, but we are all hoping for the best.

The Great Crested Grebes in the absurdly sited nest on the tip of a fallen poplar tree also have eggs, as I saw one of the birds standing on the edge of the nest in that awkward posture they have, and carefully turning the eggs over with its beak. The nest is much too far away to see what is in it, even with binoculars.