Thursday, 29 December 2011

Leucistic Common Gull at Alnwickhill

Well I thought that I was going to draw a blank at Alnwickhill today. The highlights had been a pair of Goldeneye, the 5 Canada Geese just over the wall (pic below) and the unprecedented sighting of another birder at the site (nice to meet you Billy). Even the latter didn't seem to be enough to tempt any white-winged gulls into view. Or was it? As I got ready to leave, I had one last scan and this is what I saw in among a small group of Common Gulls.

Through binoculars the paler mantle and apparently abraded coverts reminded me of a Ring-billed Gull similar to this one (right) photographed in California in April 2010.

Through the scope it was clear that the wing coverts of today's bird were not abraded but simply lacking in pigment. This leucism was presumably responsible for the paler mantle shade. So, a partially leucistic Common Gull - not unheard of, but certainly not common. After a short time bathing this rather unusual looking leucistic gull took off and joined the stream of gulls heading for the coast during the late afternoon.

Wednesday, 28 December 2011

Iceland Gull returns to Alnwickhill

I had given up on the 1st winter Iceland Gull returning to Alnwickhill, but it was there again today at lunchtime. A quick visit coincided with some very unpleasant weather and I was in two minds whether to bother getting out of the car. I'm glad I did as the Iceland Gull was one of the few birds on the filter beds and it did not seem in the least perturbed by the conditions. It generally sat tight in comparison to the Herring Gulls which were arriving to bathe. Once again the coarse markings of the Iceland Gull were apparent. Head-on, in particular, it could be the darkest gull in the group.

 I thought the weather was about to improve...
 ... but no...
Sadly, the weather beat me eventually - look at that spray! Iceland Gull in foreground
I was hoping that it was going to fly around a little, but a single wing-flap was all it managed... Think I'll pop back later when the rain has stopped...

Argentatus Herring Gulls at Alnwickhill

It has all been happening at Alnwickhill over the festive period. The lack of workmen on site has tempted back a flock of 90 Lapwing along with a variety of wildfowl including Canada Geese, Mute Swans and 7 Goosander. After a couple of days of gales, when the best I could manage was a colour-ringed Herring Gull (green-white-green on right leg - maybe from a Glasgow project?), today's calm conditions brought the gulls down in droves to bathe. A very brief visit this morning gave views of a 2CY Common Gull with dark markings on the tail and tertials - an uncommon plumage type that I don't think I have seen before.

This afternoon I had a little more time and was treated to squadrons of Herring Gulls dropping in to bathe in the nearest pool - not something they do very often and I think it is possibly related to wind direction. In amongst these I managed to pick out a couple of individuals showing the thayeri pattern on P9 as well as a couple of darker individuals with much white in the primaries - presumably northern argentatus Herring Gulls. In addition there were plenty of Common Gulls and Black-headed Gulls, as well as single Great Black-backed and Lesser Black-backed Gulls.

Biggest puzzler was the following bird which resembled a hybrid Herring Gull x Lesser Black-backed Gull but on reflection must be a subadult northern argentatus Herring Gull. One difficulty with its identification is that these northern Herring Gulls normally have a restricted amount of black in the primaries but this bird has black markings extending to P5. Of course this may be normal for birds of this age. It may, of course, be a darker than normal southern argentatus.

Obviously it is the upper bird in the first photo, which shows a pale mantled argenteus Herring Gull in front. The second picture shows the spread wingtip pattern.

The underwing can be seen in the shot below and this is followed by another shot of the bird on the water bathing with a Herring Gull.

Finally, some shots of the bird perched with argenteus Herring Gulls. Notice that the contrast between them and the argentatus appears less. In the last shot the difference between the two gulls does seem to be appropriate for northern argentatus and local argenteus.

Thanks to feedback from Stephen W and Andy (tittletattler) on BirdForum on this bird.

Here are some other pictures taken at Alnwickhill today:

Lesser Black-backed Gull (note the Black-headed Gull advancing into breeding plumage in the foreground - not the full hood it looks like from this angle but half-way there)

adult northern argentatus Herring Gull (much white on wingtips and darker upper parts than bird to its right)

thayeri-pattern Herring Gulls - two different individuals both with thayeri pattern on P9 (not quite visible in upperwing shot)


 Goosander (left of centre) and preening Great Black-backed Gull (far right, honest!)

 Grey Heron, Mute Swans and Canada Geese

Not a bad haul for Alnwickhill!

Saturday, 24 December 2011

White Christmas: adult Med Gull at Alnwickhill

Another quick trip up to Alnwickhill pays off with an unringed adult winter Mediterranean Gull dropping in to bathe and loaf around with around 100 Black-headed Gulls. Fantastically white winged in flight, the Med Gull has to rank as one of my favourite species; watching it float around in the blustery wind after bathing was particularly enjoyable - particularly as this was the trip to try out the Opticron HDF eyepiece with the Kowa TSN4 scope body. A stunning optical improvement just in time for a stunning gull.

Other Alnwickhill news is that the 5 Canada Geese and 1 hybrid Canada x Greylag Goose have been replaced overnight by 7 Greylag Geese!

Tuesday, 20 December 2011

Hartlaub's Gull at Robben Island

I was trawling through some pictures from a 2007 trip to South Africa and found a picture of this Hartlaub's Gull taken on Robben Island off Cape Town. I had forgotten that I had kept a shot of this species as gulls are clearly not the main focus of attention of any visit to Robben Island - the tour from a former inmate was an unforgettably moving experience and the shot below captures some of the grim reality for those imprisoned on the island.

On return to Cape Town, these sealions provided much needed light relief after an intense day focusing on human resilience in the face of oppression.

Sunday, 18 December 2011

Another first winter Iceland Gull at Alnwickhill

I was grilling the Common Gulls at Alnwickhill this morning trying to re-find yesterday's rosy individual when a 'white-winger' caught my eye. Well, I have never managed to see very many Iceland Gulls, so I was really delighted when the white shape turned into the second 1st winter Iceland Gull for Alnwickhill this year.

Today's bird was distinctly darker and greyer than the March bird. In particular its flight feathers seemed to have a greyish wash across them and dark subterminal markings. I could not detect any real contrast between the outer primaries and the inner primaries so I do not think that Kumlien's Gull is a real possibility, but nevertheless it is not the most straightforward glaucoides Iceland Gull either. That said, the strong light this morning was playing havoc with both my camera's and my eyes' abilities to resolve subtle shades. Not that I am complaining that the sun is out in December of course...