Cliffe warming up and urban flora lecture

A fair walk through the middle of Cliffe to the viewpoint at Flamingo was enjoyable for both Monty and myself at lunchtime, which was followed by a trip up to Birkbeck for a lecture on the wonders of the urban flora to feed the mind, to make another great day!

Common Gulls. On the bridge "over the Kwai", there were two Common Gulls, Larus canus, and two black-headed gulls, Chroicocephalus ridibundus. The two Common Gulls were nicely showing the bright white on the trailing edge of the wings, and the white tertial crescent, as well as the white mirror segments on the black wingtips.

The Common Gull to the right has a darker head, and less clear white spotting on the black wing tips. If it might be possible to persuade myself that there are dark marks on the wings themselves, then perhaps it could be a second year winter bird?

Black-Headed Gulls. The settled bird of the two Black-Headed Gulls here is turning dark on the head as it develops its breeding plumage, nicely showing the white eyelids more visible to the rear of the eye. The flying bird, about to land and decelerating sharply, does not appear to be so well advanced, but does show the wing patterns quite well, the dark "shadow" on the underside, the black-tipped primaries, the bright white triangle and front edge to the wings. There is also a dark mark at the front of the upper wing that might indicate a second winter bird as opposed to an adult bird.

And these other two birds seems to be mutually displaying to the other. According to BWP this could perhaps be "The Forward Posture", bird flat with spread scapulars, neck kinked and head held forward (although difficult to tell if the tail is flattened), generally a symbol of aggression often alternately shown by the two opponents, more commonly on the water (e.g. swimming towards opponent) than on land. A web source from a Dutch "larophile" says that it may also be part of courtship if the birds are parallel to each other, which doesn't seem to be the case here. This display itself may therefore be nothing to do with the season!

In his book The Animal in Its World, Niko Tinbergen characterizes this type of behavior as a ‘spacing-out’ display or ‘threat’ display, directed at opponents with the aim to move them away or to stop their advance.
The last picture also seems to involve mutual ritualistic postures, with spread scapulars retained, a little more like "The Upright Posture" or "The Oblique Posture", although I can't identify it exactly. One thing I can't sort out is that it doesn't look aggressive, and the birds are close together in this last shot.

However that may be, I also think that the birds' beaks are losing their red colour and becoming darker, almost black at a distance. In addition at least one of the bird's head is beginning to darken. Spring, I think, is still on the way!

Urban flora lecture. The wall bedstraw, Galium parisiense, was found in a front garden just by Gloucester Road tube station, and is a rare plant of poor ground and urban as well as rural areas.

Oare marshes in the iron grip

This drake shoveller shows the wing pattern quite well!

Access trail

Nothing much to report today, and no photos, but a really nice walk around the access trail. Better light than yesterday, and it was still light after five as well. Great tits, blue tits, long-tailed tits, blackbirds, robins, fieldfare, chaffinch. The Great tits and the Blue tits were singing as the sun set.

Snowy Hadlow

Down at the sewage farm the black-headed gulls were making their usual racket. Once again the quickfix button was required to get the muddiness out of the photos. This is an adult-plumaged bird in flight, with a first (or second - see below??) winter bird at rest behind it:

Here you can see a clearly first winter bird on the right, an adult bird on the left, and an intermediate in between. This intermediate plumage bird could just possibly be a second winter bird, 5% of which are supposed to have gained their grey wings but still have some brown patches on the tertials, although these do seem rather large brown patches, compared to the books!

Here is an adult-plumaged bird checking out the filter bed:

A good view of the "adult" underwing pattern:

And here are two yellow wagtails, only just visible as blurs as they are put up by the gulls, but clearly recognisable all the same. One of the birds can be seen at rest on a rail in a couple of other photos, more or less in the same place.

Lower Temperatures at Lower Halstow

As the temperature dropped to near freezing before the first serious threat of snowfall this winter I went back to the Lower Halstow walk I did with Geoff Orton of the the Kent Wildlife Trust back in the late autumn of 2011. There were many dog-walkers, but still plenty of birds out on the mud, with quite a few Dunlin, Calidris alpina, fairly close in.

The use of quick fix enhancement really raises the contrast on these pictures, which look very muddy without it! You can see the eye stripe on some of the Dunlin, but perhaps not so easily in this enhanced picture.

Whetsted Gravel Pits

Chaffinches, Blackbirds, Goldfinches on the way by Victoria Road and Kelchers, 3 Great Tits, 1 Blue Tit, 1 Green Woodpecker, 5 Mute Swans on the field. 120+ Greylag geese, including 3+ several farmyard hybrids, 1 Great Crested Grebe, 2 + 5 Black-headed Gulls, 2+ Blackbirds, 3 Blue Tits, 1 Great Tit, 1 Woodpigeon, 1 headbobbing drake + 1 duck Mallard, 2 + 2 Tufted Duck, 2 + 10 Pochard, 52 Coot, some necksliding, 6+ Little Grebe, 2 Cormorant, 2 Grey Heron, 9 Greylag geese, 2 Great Crested Grebe, 1 developing breeding plumage, 5 + 76 Black-headed Gulls, 7 + 11 Tufted Duck, 62 Coot, 18 Cormorant developing breeding plumages, 19 + 16 Gadwall, 1 drake Goosander, 3 Common Gulls, 1 Herring Gull, 4 adult + 3 juvenile Swans.

Green Sandpiper at Cliffe

A good all the way round walk of just over four miles certainly tired Monty out, and my knees felt it as well.
The new camera lens worked excellently and gave me as good detail at long distance as I think I could have hoped for. I tried to do a count of some of the waterbirds, and got good numbers of coot, tufted, mallard, teal, shoveller and some pintail duck, and a good group of greylag geeses, together with lapwing and godwits, at least some of which (probably all) were black-tailed. although the RSPB website claims high numbers of Dunlin can be seen at the reserve I have only seen the occasional handful.

On the far side of the radar pool, a gull was beating up the coots on the water, and then I got a long-distance snap of it as it wheeled away:

It is a Common Gull, but I am pretty sure it is a second winter bird, because of the dark brown patches at the front and back of the upper wing just to the inside of the black wing tip patches, and also the reduced white mirrors at the very tips of the wings.

Other gulls were wheeling around and they might also have been common gulls at a guess, young ones mainly. I got one shot at the precise moment that an adult wheeled close to the surface of the water, its wingtip apparently only an inch or two from cutting into the surface:

I missed most of the ships coming in and out of the Thames but here is a shot of the relatively small dredger "Marieke" coming up river across the Marsh, and then another shot, closer to.

As we went around the Mead wall I shouted at Monty rolling in some muck by the side of the path and thereby put up a smallish dark wader with a very distinct white rump. According to the sightings board, Green Sandpipers have been around for several weeks, so it was probably a Green Sandpiper, Tringa ochropus, my first ever properly identified -  However I am now quite certain that I had misidentified the two waders I saw in the autumn which I had called Curlew Sandpipers on the basis of their white rumps alone - in my ignorance - they were almost certainly my first Green Sandpipers. So what made me think the bird today was definitely a Green Sandpiper on the spot this time? It was the very dark colouring to the upperparts, the very distinct white rump, the sandpiper-like look to the bird in flight, the sandpiper call just like the Green Sandpiper on Xeno-Canto (a three note whistle), and of course the fact that the Sightings Board predicted that Green Sandpiper was there!

This is from the Itchen birds website (I hope they don't mind!

The Green Sandpiper actually nests in old nests of other species of birds, such as a Fieldfare (Turdus pilaris) or a woodpigeon (Columba palumbus) or a squirrel (Sciurus) drey in trees (!), or on stumps or mounds where trees are unavailable. Separate nesting and feeding territories are thought to be held. little extra nesting material will be added to the existing structure, although some may be re-arranged. This nesting style is rather like the related Solitary Sandpiper in North America and the two together are thought to be quite close to the ancestral Tringa type.

The Green Sandpiper lays 2–4 cream with brown or purplish blotches eggs in a clutch, which take about three weeks to hatch. Incubation is by both parents, starting with the last egg, and hatching is synchronous. The young are precocial and nidifugous.

The species is generally said to be one of the darkest on the upper-side in its group, and in non-breeding plumage, there are none of the myriad small light spots that grace the breeding plumage. Although the upperparts are therefore darker, in contrast the underparts are whiter at this time of the year.

The birds breed in areas such as the Sweden and Finland. The range is quite wide, and extends through the Sub-Artic region North to the Low Artic, and through the Boreal region South to the Temperate, with a montane outlier in Transcaucasia. Females tend to leave the breeding grounds first, perhaps before the young are fledged, followed later by the juveniles and the males.

They winter in Western Europe (a few), around the Mediterranean, in Africa or across Asia, to avoid the snow and ice that would cause them to starve on their breeding grounds. In Britain most over-wintering birds are found in Southern Britain.

Feeding is relatively secretive, regularly entering ditches, stream beds and enclosed ponds, shunning wide horizons and open coastal habitats. In such habitats the only waders likely to be seen are Snipe, Common Sandpiper and Green Sandpiper. The only one of these with a bright white rump is the Green Sandpiper. Food is small invertebrate items picked off the mud (it isn't a great "prober") as the bird works steadily around the edges of its chosen pond. The picture below shows the somewhat sheltered ditch that my particular bird was seen at - doesn't seem to exactly fit.

As the light faded, I tried to see the gulls behind a large ship going out, but failed to get much detail. Possibilities of a couple in the crowd, where the dark wings and whitish tail were caught by the sun, included Black-Backed Gulls, either Lesser or Greater. Others could have been Herring Gulls.

As I looked, a large cloud of waders (at least 150) flew rapidly upriver, too fast and small for curlews. The beaks I thought looked relatively small, so my best guess would be Grey or Golden Plovers, but they could have been a lot of other things as well.