The weather was overcast with a cool breeze today, but no threat of rain. It certainly felt autumnal, a feeling emphasised by the fireworks over the last few nights, celebrating Guy Fawkes infamous attempt at mass murder.
In the late morning Monty and I headed off down to the Gravel Pits, to see whether the waterfowl were concentrating inland yet in preparation for the hard weather. There were a lot of dog-walkers and other people out enjoying the countryside on the way down to the River at East Lock, but not everybody crosses the river and gets as far as the pits themselves, and the ducks and gulls seemed fairly undisturbed when I arrived. Monty had done a lot of running about by then, and I felt justified in putting him on a lead when I got to the causeway, in order to prevent him jumping into the peaceful quiet ditch and the shallow gravel pit and scaring the birds.
The waterfowl is building up very nicely on the two large pits that I can look at!
The first photo is of a fairly close mute swan, Cygnus olor, which came out quite well, using ISO 2000 to give a very quick exposure of 1/1250th of a second which reduces camera shake and at an aperture of f11 to give a good depth of exposure. The resulting noise from the high ISO doesn't matter too much at this limited degree of cropping!
This mallard duck, Anas platyrynchos, is right on the far side of the first gravel pit, and the picture has been cropped much more heavily than the picture of the swan, so it is much more at risk of noise from the high ISO, which can be seen. I did need this ISO, as even with this I was only getting 1/640th (just above spec. for the lens used to keep shake under control) at f8, just sufficient for the depth of field required. Using the telescope on the tripod to steady the camera did help to reduce the risk of camera shake, and overall I was very pleased with this attempt.
This Little Grebe, Tachybaptus ruficollis, is at a closer distance than the Mallard, but the picture has been more heavily cropped, and shows the downside of noise and perhaps some camera shake. The picture is here to compare sizes of the grebe and coot (although the grebe is further away) but also because the coot is waggling something about in its bill - it seemed to do this for some time. Again I was quite pleased with picture overall. The ISO 2000 gave me a 1/1000th exposure with an f8 aperture, although the depth of field might perhaps have been a bit poor, with the centre of the focus being on the grebe, leaving the coot slightly out of focus.
There was a small flock of chaffinches, Fringilla coelebs, feeding off the seed heads on the causeway, and this female returned to the fence fairly close by and stayed long enough for me to get a reasonable shot. Again I think the high ISO helped, giving 1/640th at f8, although it could be easy to overdo it.
This juvenile swan has been diving after vegetation and water is still dripping from his beak. The picture is helped by the rapid exposure of 1/800th, again forced by the high ISO.
After checking out the first pit, I collected Monty and we moved on to the second pit, where I think we disturbed the Greylag Geese from the central gull roost. By the time I got the camera out, the geese had gone off to join the others on the far bank. The gulls on the roost were undisturbed and were almost entirely black-headed gulls, Chroicocephalus ridibundus, but noticeable by their size, there were a couple of adult and juvenile herring gulls, Larus argentatus, mixed into the crowd.
I've been looking for a Common Gull, Larus canus, for some time now, in amongst the others. One reason for my failure has perhaps been my lack of concentration on the identification features of the different stages and plumages. One characteristic of the winter plumage which hadn't really occurred to me is that Common Gulls have a greyish hood at this time of year.
While looking at this character in the book that evening, I realised that I had seen a similar hooded bird in the photos I had taken today. I have always in this past assumed this to be the rather similar hood of the developing black head of the black headed gull, but I looked through the photos again, and found several of the same grey hooded bird in flight. They were completely ambiguous about the identity of the gull - it could equally well have been black-headed, or common, or another gull altogether.
And then - Eureka!! I got a picture of the same bird still in flight, still showing the slight hood, but this time clearly showing the significant bright white "mirrors" embedded in the black wing tips on the upper side of the wings - on a bird this size these are fairly diagnostic of my FIRST definitely identified Common Gull! What a lucky shot!
All this progress is down to doing this blog, and going carefully over the material for it - its definitely improving my identification of all sorts of organisms. what a great picture, even if its cropped to very fuzzy limits.
Now that I've got my eye in, I'm sure there were other common gulls there. Here is a possible, perched on this front post, in front of a black headed gull scratching itself in the first picture. Common Gulls (38 - 43 cm) are larger than the black-headed (35 - 38), but smaller than the herring gulls (53 - 59), although sizes can be tricky to judge. The first picture was at ISO 250, the next at ISO 2000, and the last at ISO 6500. I can't say they were comparable because of variable vegetation blocking the view in the forefront, but on the other hand I can't see that the ultra-high ISO value is causing me such problems that I cannot identify the bird. In all three shots I used the telescope to steady the camera.
The next three photos of a black-headed gull are very heavy crops at ISOs 2000 (1/800th), 6500 (1/1600th) and 200 (1/250th), the last showing movement - this is why it is so necessary to avoid these slower exposures at longer distances. Using a sufficient ISO to give an exposure of 1/500th to 1/1000th seems sensible, without any need to over-egg the pudding further.
Walking along the causeway of the second pit I was delighted to see some Hawkweed Oxtongue, Picris hieracioides, still in flower, amongst the declining Bristly Oxtongue.
Here is a Black-Headed gull in flight, to compare the upper wing pattern with that of the Common Gull
and to show the dark under wing
On the way back to the car and home, there were still loads of things to look out for and think about. These look like Horse Mushrooms, Agaricus sp. in the middle of the germinating wheat crop
The Ivy, Hedera helix, flowers in the hedgerows are now nearly all gone, and berrying up for the winter. I'm not sure if they are popular with the birds
On the other hand I do know how popular the Hawthorn, Crataegus monogyna, berries are!
One tired, and very serious looking, but satisfied dog, at the end of a good walk! What an excellent job he has done today, as always, exploring the countryside, checking it out, leading and guarding me - and he takes these responsibilities very seriously indeed!
The Pedunculate Oak trees, Quercus robur, are still holding their leaves in the autumnal landscape
I'm still not sure why this field has been sown in two separate halves, but it may become clearer at harvest next summer
Total estimates of bird numbers for the day were
6 (plus 1 juvenile) mute swans, 3 cormorants, 90+ coot, c. 200 greylag geese, 5 tufted ducks, 40+ gadwall, 16+ shoveller, 5 mallard, 3 great crested grebes, 9 little grebes, 80 black-headed gulls, 3 herring gulls, 1 green woodpecker, 9 fieldfares.
In the late morning Monty and I headed off down to the Gravel Pits, to see whether the waterfowl were concentrating inland yet in preparation for the hard weather. There were a lot of dog-walkers and other people out enjoying the countryside on the way down to the River at East Lock, but not everybody crosses the river and gets as far as the pits themselves, and the ducks and gulls seemed fairly undisturbed when I arrived. Monty had done a lot of running about by then, and I felt justified in putting him on a lead when I got to the causeway, in order to prevent him jumping into the peaceful quiet ditch and the shallow gravel pit and scaring the birds.
The first photo is of a fairly close mute swan, Cygnus olor, which came out quite well, using ISO 2000 to give a very quick exposure of 1/1250th of a second which reduces camera shake and at an aperture of f11 to give a good depth of exposure. The resulting noise from the high ISO doesn't matter too much at this limited degree of cropping!
While looking at this character in the book that evening, I realised that I had seen a similar hooded bird in the photos I had taken today. I have always in this past assumed this to be the rather similar hood of the developing black head of the black headed gull, but I looked through the photos again, and found several of the same grey hooded bird in flight. They were completely ambiguous about the identity of the gull - it could equally well have been black-headed, or common, or another gull altogether.
And then - Eureka!! I got a picture of the same bird still in flight, still showing the slight hood, but this time clearly showing the significant bright white "mirrors" embedded in the black wing tips on the upper side of the wings - on a bird this size these are fairly diagnostic of my FIRST definitely identified Common Gull! What a lucky shot!
All this progress is down to doing this blog, and going carefully over the material for it - its definitely improving my identification of all sorts of organisms. what a great picture, even if its cropped to very fuzzy limits.
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