First two weeks of February

Birding over the last couple weeks has been largely the same as January. Storms Dennis and Ciara have made birding impossible on some days, but at least the floods have been topped up again. The first oystercatcher of the year arrived on 8th February, and several ruff, dunlin and redshank have been seen with the lapwing flock, along with some large counts of golden plover. Still no black tailed godwits, however, which is something to look out for in the coming weeks. A rather uneventful WeBS count on 12th February revealed little hidden amongst the wildfowl, although I had a peak count of eight shelduck.

On the gulling front I've had a couple more Caspian gulls and a few Yellow legged gulls but not much else. On 10th February I had good views of a first winter bird that I had previously seen distantly in December and a couple times subsequently. Initially I had called it as a Caspian gull, then downgraded it to a hybrid when I saw it distantly in flight, as it had dark underwings. This was the first opportunity I had to study it up close and it proved to be a very informative bird. There are a few features on this bird that are a bit "herring-y" - dark underwings, faint streaking on the head, and a rather average looking bill.  Using the Gibbins et al 2011 trait scoring system, which aims to remove some subjectivity from Caspian gull identification, I scored this bird as 22. This is within range of a pure Caspian gull (12-25) but also in range of a hybrid Herring x Caspian (22-32) - the authors state that the upper limit for safe identification as a pure Caspian is 21. Therefore, based on this study it is impossible to say whether this individual is an ugly looking pure Caspian or a hybrid.




However, I decided to put some images of this bird on Twitter, and received some positive comments from London birders who have the opportunity to study large numbers of Caspian gulls up close on the Thames estuary. They see lots of birds from mixed colonies in Germany, which can often be identified from yellow X colour rings. They said that this bird would make the grade as a Caspian in the South East - interestingly, it seems that the westward expansion of Caspian gulls into Germany since the Gibbins paper was published means that more and more "not so classic" individuals are being seen in Britain. It seems silly to ignore such birds when many are just slightly "impure", with some herring genes somewhere down the line, rather than a first generation or even second generation hybrid. Based on this feedback I'm happy to count it - I've certainly seen worse hybrids on the Meadow this winter. Before long I think we will have to start recording them as "Caspian-type" gulls anyway.

On 12th February I had an exceptional count of four different Caspian gulls in the roost - an absolutely beautiful second winter bird with massive p10 mirrors, "Graham" (nice to see it back in the roost after a week's absence), the other regular first winter and the bird above. In addition there were at least five Yellow-legged gulls - one of the best roosts I have ever seen on the meadow, with huge numbers of gulls floating close in on the water in very calm conditions.


Still no white wingers however which is disappointing - we can't possibility go a second year in a row without one on the Meadow! Another bird to look out for are storm-driven kittiwakes, which are a real possibility after the recent weather.

Thomas

Caspian gulls so far

Over the past few weeks birding has been excellent on the meadow, with extensive floods leading to large numbers of gulls roosting each night. Searching through these gulls has revealed the presence of Yellow-legged gulls and Caspian gulls, with the latter being particularly sought after.

I generally find that numbers of Caspian gulls on the meadow tend to peak in January and February - indeed, I did not record any Caspian gulls before the new year, despite individuals being reported at other sites in Oxfordshire. Since finding my first bird of the winter season at the start of January, Caspian gulls have roosted on the meadow almost daily - indeed, I now regard it as a bad day when I fail to see one in the roost!

One of the joys of gull watching is not only the identification of Caspian gulls, but also being able to recognise individual birds - is this first winter Casp in the roost a new bird, or a familiar face? This is easy when individuals are of different ages, and careful examination of feather patterning, extent of moult and overall structure/expression (aided by a photographic record of all individuals seen) enables individuals of the same age to be differentiated.

I have been able to determine that at least eight, probably nine different Caspian gulls have visited the Port Meadow roost this season - an exceptional number, already breaking last year's total of seven and with previous years only averaging 3-5 birds. Below, I will give an account of the various birds seen so far. Hopefully, this will allow these birds to be recognised at different locations in the county and further afield.

Bird 1 - "Graham"

Graham, rather like myself, has been a regular at the Port Meadow roost over the last few weeks. Given how reliable it has been, I thought it deserved a name. First seen on 12th January, it has roosted several times a week since then. It is a rather dainty bird,  with its underparts and flanks being at the darker end of the spectrum, but with otherwise classic features.





Bird 2

Bird 2 is a large third winter with a thick bill, so far only seen once, on 15th January with Will Langdon. It retains a neck shawl and some dark centred tertials, enabling it to be distinguished from the other third winters.



Bird 3

Bird 3, an adult, was first seen on 20th January and has since roosted twice more. A classic bird, probably female given its thin bill and overall structure.





Bird 4

This second winter bird on 23rd January was extremely distant but showed all of the classic features one might expect in a Caspian gull of this age. I think I can even make out a p10 mirror in a few of the frames, although this might be a bit optimistic given the distances involved!



Bird 5

A new first winter bird arrived in the roost well after sunset on 24th January. I was left dissatisfied with my views and even less happy with the images of the bird - in fact, I was barely able to differentiate it from Graham (which was also roosting that night), and only realised it was a second bird when I noticed Graham on a different part of the flood. Thankfully, it has since roosted twice more, and with much better views has revealed itself to be a very different bird. It is quite large, and its bill is rather thick with a prominent gonys, indicating that it is probably a male. It can be differentiated from Graham by its more advanced covert moult, with several replaced median coverts and one obvious replaced inner greater covert. It is also whiter overall than Graham.




Bird 6

This third winter bird roosted on 28th January. It looks extremely similar to a bird I saw at Appleford gravel pit on 24th January in terms of its jizz, bill pattern and most plumage traits. However, it lacks a neck shawl, which was definitely present on the Appleford bird - either it has moulted these feathers in the days between sightings, or there are two very similar third winters in the county. It is also differentiated from bird 2 by its adult-type tertials and white tips to primaries.



Bird 7

Another first winter bird roosted on 1st February, with subtly different scapular patterning and slight notching on some of the inner greater coverts.





Bird 8

Bird 8 was found by Adam on 1st February - an absolutely classic third winter. Certainly different to the previous two birds, with its combination of neck shawl, some retained brown median coverts and white-tipped primaries. It is also different to the Appleford bird (if we assume that bird 6 is not the Appleford bird) on basis of primary pattern.


Comparison between the primary pattern of bird 8 (left) and the Appleford bird (right). The Appleford bird's p9 and p10 mirrors are smaller than bird 8, in particular, the p9 mirror in the Appleford bird is just a speck.

Bird 9 - probably!

On 23rd January I saw a possible third winter Caspian gull. I judged the bird to be dark eyed, have a white head, a long, pale coloured bill with black markings and a slightly darker mantle than the surrounding herring gulls. However, due to the distances involved (several hundred metres) and the fact that it was slightly obscured, making it difficult to assess structure, I left it as a possible and panned to the right, immediately picking out a second winter Casp, bird 4, that I began to video through my scope. After this I then failed to relocate the third winter bird.

Upon reviewing the video of bird 4 I was surprised to see the third winter walk in from the left of the frame, give a long call in a classic albatross pose typical of cachinnans. The video also reveals some faint streaking to the back of the neck, and shows how long the bird's legs are - the overall jizz is perfect. Note also the reaction it elicits from the second winter Caspian gull! Despite this I feel that it would be very hard to rule out a hybrid with herring gull, especially as I did not spend very long actually looking at it in the field. Therefore leaving it as a probable for now - I hope that it roosts again!



So there we have it - 3 first winters, a second winter, 3/4 third winters and an adult so far. With most of February still to come, and the floods still attracting a large numbers of gulls, I'm hoping that we'll get a few more Caspian gulls choosing to roost - there are certainly other individuals photographed at other locations in the county that haven't yet made it to Port Meadow. Looking forward, there is also the possibility of Iceland and Glaucous gulls dropping in - we failed to get any white wingers on the meadow last year, so fingers crossed for the next few weeks.

Thomas

January Round-up

I just thought I'd do a round-up of what's been going on in January in order to bring readers up to speed on the present situation on the Meadow. Largely it's been the usual birds that one might expect for the time of year but there have been one or two points of particular interest.

As always at this time of year the quality of birding tracks the ebb and flow of the floods themselves. We had some very wet weather this month which did lead to the river bursting its banks at one stage and which lead to some superb conditions on the floods and birds absolutely everywhere you looked. The BARNACLE GEESE have been regular visitors to the floods at this time of year with their distinctive calls as they fly in (always from the north) drawing attention to their arrival. We also had an EGYPTIAN GOOSE this month, a bit less than annual visitor to the floods. On the wader front as well as the usual REDSHANK and DUNLIN we've also had a flock of up to six RUFF in amongst the Lapwing. Whilst in winters gone by this would be completely normal, sadly over the last few years Ruff has stopped being so regular and they are now less than annual. We've also being getting some sporadic Golden Plover flocks of a few hundred: not like the old days but they all seem to be at Otmoor where there are thousands at present. During the peak flood period we did have a flock of several hundred Lapwing, which is quite a good count for the Meadow. Other notable sightings include a PERGERINE flying low over Walton Street (yes, I'm counting that) and a RAVEN in Burgess Field.

But it's been the gulling which has really been where all the action is. Thanks to Thomas Miller's enthusiasm there have now been 8 different CASPIAN GULLS that he's identified over the course of the month. For regular visitors to the roost he's even been given them names. During a rare free afternoon I joined him for some grilling of the roost where in freezing conditions we managed between us to find two new birds as well as one returner, so three Caspians in the roost - quite amazing! Thomas is going to do a review of all the different gulls that he's found so far so expect more gull-heavy posts over the coming weeks.

A new 3rd winter Caspian Gull, photo courtesy of Thomas Miller
Finally I should mention the Trap Grounds blog which is being updated regularly and which is always worth a read. I remember sometime back writing in my Gnome's Birding Diary blog that should I ever find myself twitching a Slime Mould that someone should shoot me on the spot. Well today I did just that, paying homage to the rare Badhamia utricularis that Nicola Devine had found on a log. It starts out yellow (see here) before turning a deep purple as you can see from my photo below.

Badhamia utricularis - a Slime Mould

Adam