Yellow legged Herring Gull and Common Redpoll

A pair of bright yellow legs stood out at Seafield this morning. Not the mythical Yellow-legged Gull but a Yellow-legged Herring Gull - probably from the Baltic population of Herring Gulls that often show these custard yellow legs. A nice bird and the most custard-like one I have seen yet. The wing formula is not easy to interpret but P6 has a solid band and P5 just a couple of isolated spots.

Also a brownish Common Redpoll at Figgate Park today. A rarity in Lothian requiring a description but I can't get excited about this bird as it is so subtle and as they should be lumped with Lessers anyway! So why is it not a Lesser - well in my opinion its white covert bars, pale rump and slightly greyish brown tone point to Common. In life it appeared at the large end of the scale for a redpoll and seemed to have a pretty extensive primary projection. The reality is who knows... I'm sure plenty of folk would consider it on the Lesser-Mealy borderline.

Hybrid Herring x Lesser Black-backed Gull in Edinburgh

Probably the best shot showing the ring on the right leg - palish yellow legs and mid-toned grey uppers

Hybrid gulls... By looking closely at the gulls of Edinburgh and Lothian over the last couple of years I've seen quite a few probable Herring x LBB Gulls without yet connecting with a YLG or Caspo. I was seriously considering making 2014 a hybrid-gull-free year by taking a beak from the search for southern European larids in and around Edinburgh. Well, what do you know, a hybrid argentatus x fuscus seems to have taken a shine to the grassy pitch outside my office window in Merchiston. It has been there for the last two mornings, but has disappeared before the light has been good enough for decent photographs. Even with my DSLR on hand this morning the shots are poor. Both days I have seen it in direct comparison with Herring Gulls and a single Lesser Black-backed Gull. Its mid-tone mantle and upperwing plus yellow legs are distinctive. Excitingly the bird is ringed on its right leg - although it will take a miracle to get close enough for a ring read I would imagine.

Hybrid HerringxLBB Gull on right with Herring Gull

A poor shot in the low light levels - but the wing-tip pattern can just about be discerned - a narrow band on P5 and typical pattern for hybrid

Sub-adult hybrid Herring x LBB Gull, Skateraw, 15 December 2013

 

 

I had only commented on Twitter yesterday that I had been unable to find a hybrid gull in Edinburgh for a few months (despite looking hard) when I picked one out at Skateraw Landfill site East Lothian today. Viewing is distant and the images poor. Aging these subadults is hard as I am pretty sure they follow their own rules in terms of plumage. This individual has white underparts and tail and a clear trailing edge on the open wing but signs of immaturity in the coverts and tertials.

Steel grey Scandinavian Herring Gull

I can't be sure without a colour ring, but I think that this Herring Gull has crossed the North Sea for its winter break in Musselburgh. The steel-like grey upperpart tone combined with reduced black in their outer primaries are pointers to the identification of Scandinavian Herring Gulls. Another bird at Seafield this morning was darker grey and had thayeri-like wingtip pattern - that's a classic combination for a northern argentatus. This one is slightly trickier on both counts, so maybe its origins are slightly less far north?

Scandinavian HerringGull (subspecies argentatus) at Seafield

It has been an extremely quiet autumn for me bird-wise - lots of looking but not much finding. I have not once managed to time a trip to the East coast that coincides with decent conditions for grounded migrants. Other than a few brief views of YBWs, a very brief Sardinian Warbler and another self found Ring-billed Gull (in Dublin, of course), decent birds have been conspicuous by their absence.



Today I managed to squeeze in an hour or so at Seafield and the best I could manage was my first Scandinavian Herring Gull of this coming winter season. This bird had very little black in its wing-tip compared to our breeding birds and an upperpart shade that is darker. In the shot of it on the shore it can be seen that it is obviously darker than the accompanying Black-headed Gulls. Note that P10 is still growing on this bird and that P9 shows no back extending to the web - ie a thayeri pattern. More often, in my experience, these northern gulls keep their distance and seeing these details can be tricky. This one today treated me to a nice flypast.

Scandinavian Herring Gull standing in water to right of roosting BhGs

LBB x Herring Gull hybrid, Musselburgh, 8 Aug 2013

Lesser Black-backed Gull, hybrid LBBxHerring Gull, Herring Gull (top–bottom)

I popped along to Musselburgh mid-afternoon to check the gulls. Loafing among the gulls along the river was one of the hybrid LBB x Herring Gulls that I found earlier in the week. I managed a better mantle comparison shot for this bird (Bird 2) than I managed earlier in the week. The (feral/formerly injured) Pink-footed Goose was back in the area - I haven't seen it for quite a few months.

Another mantle shade comparison but this time with a Common Gull with an apricot or rosy hue to its breast and underparts (centre). The hue is stronger in life than is captured by the camera.

Also of note was the first juvenile Common Gull that I have seen this season. It was alongside some adults that were hidden in among the Kittiwakes at the roost. One of the adult Common Gulls had the apricot (or rosy) tint to its white plumage. This seems to be very unusual - I think it is only the third individual that I have seen with this tint in the last three years (for one bird see here and here). It could, of course, be that I have seen the same individual three times. I have photographed this plumage tint before - although it seems that (like the rosy tint in other small gulls) the human retina is better at seeing it than the digital sensor in a camera.

Two more Herring x LBB Gull hybrids - this time at Musselburgh

Comparison shot showing different mantle tones of argenteus Herring Gull (left), graellsii Lesser Black-backed Gull (right) and Herring x LBBG hybrid (centre). This is Bird 1 of 2.

A extremely good morning of gulling at Musselburgh with Little Gull, Kittiwake and juvenile Mediterranean Gull (another!) at the Esk mouth and two hybrid Herring x Lesser Black-backed Gulls along the grassy banks of the Esk. All those Lothian year-tick waders on the scrapes (Wood Sandpipers et al.) will have to wait for another time...  Never mind, grilling these two argentatus x fuscus hybrids at close range made up for all the distant views I have had over the last few months. These hybrids closely resemble Yellow-legged Gulls, which are so rare in Lothian that every candidate has to scrutinised closely – in my experience every candidate so far has turned out to be a hybrid (see here, here, here, here and here). In addition, I now believe that this bird that I photographed at Musselburgh in 2010 and was the subject of this BirdForum thread was also a Herring x Lesser Black-backed Gull hybrid.

Here is today's first bird a sub-adult advanced third summer type plumage, perhaps, or retarded fourth summer...

Hybrid Herring x LBBG at Musselburgh 4 Aug 2013 (Bird 1): note mid grey upper tone and greyish pink leg colour. Primary projection is exaggerated by excessive wear of white margin on tertials - extent of wear can be seen by exposed rachis on furthest wing. Note band across P5 on nearest wing - narrow particularly on inner margin. Eye ring red.

Hybrid Herring x LBBG at Musselburgh 4 Aug 2013 (Bird 1): mid grey upper tone and greyish pink leg colour. Extensive black on underside of P10. Note excessive wear of what would have been a broad white margin on secondaries and tertials - extent of wear can be seen by exposed rachis. Eye ring red.

Hybrid Herring x LBBG at Musselburgh 4 Aug 2013 (Bird 1):  newly grown P1–3 show fresher colour but still overall mid grey tone. Greater signs of immaturity than expected when wings spread. P10–P5 on left wing show extent of black in outer primaries - this presumably will reduce as this moult continues and bird ages. Note band across P5 on nearest wing - narrow particularly on inner margin. Note excessive wear of white margin on inner secondaries and tertials.

Hybrid Herring x LBBG at Musselburgh 4 Aug 2013 (Bird 1): a view of the pattern of black on underside of primaries

Here is today's second bird, a sub-adult third summer type plumage, perhaps... Note that this bird is identical (apart from a slight difference to bill tip coloration) to the third cycle hybrid of known Lesser Black-backed x Herring parentage shown in plates 307–309 of Adriaens et al. (2012) Hybrid gulls in Belgium – an update British Birds 105, 530–542, which is quite easy to find online.

Hybrid Herring x LBBG at Musselburgh 4 Aug 2013 (Bird 2): note mid grey upper tone and pinkish leg colour.  Note band across P5 on nearest wing - narrow particularly on inner margin. Eye ring reddish.

Hybrid Herring x LBBG at Musselburgh 4 Aug 2013 (Bird 2): note mid grey upper tone and pinkish leg colour.  Although the bird is missing P6–7 on both wings the subterminal band pattern on both P5 can be made out here and it is complete but narrow on the inner margin.Note also the extent of black in the tail.

Hybrid Herring x LBBG at Musselburgh 4 Aug 2013 (Bird 2): P6 is growing on left wing. Extensive black/brown in the tail and extensive brown secondaries.

Hybrid Herring x LBBG at Musselburgh 4 Aug 2013 (Bird 2): Not only is this bird almost identical to the one in Adriaens et al (2012) but it is almost identical to the one I photographed nearby in 2010 and was discussed in BirdForum here.

Finally, here are both birds together, with a Herring Gull. As I was photographing the second bird the first flew up river and checked me out to see if there was any more croissant going!...

White-winged gulls in Orkney and Edinburgh, May 2013

Some great gulling last month with three different white-wingers...

Adult summer Glaucous Gull (on right), Egilsay, 16 May 2013 (with 3cy Herring Gull)

Third calendar year Iceland Gull (on right), Westray, 22 May 2013 (with adult Great Black-backed Gull, Hooded Crow and adult Herring Gull)

Adult type feathers in the back of this 3CY Iceland Gull more obvious in this shot

Isabel dilution mutant Herring Gull (centre), Seafield, Edinburgh, 29 May 2013 (with Herring Gulls)

Isabel: dilution mutant Herring Gull at Seafield again

I spent a couple of hours checking the gulls at Seafield today. While it was the Lesser Black-backed Gulls that predominated on St Margaret's Loch en route, at Seafield it was almost entirely Herring Gulls at the recycling centre. The isabel dilution mutant was the clear highlight in among the latter. It showed on three occasions and posed well on the ground as well as in flight. Very nice, thank you - I had hoped for better views and was not disappointed.

Interesting that it appears to already have dropped a couple of innermost primaries. Could this early moult may be a result of the fragility of the unpigmented feathers?

2 hybrid Herring x Lesser Black-backed Gulls at Seafield, Edinburgh

Both Herring x Lesser Black-backed Gull hybrids* were in among the gulls at Seafield today. Though it took quite a number of hours before the sub-adult (above) appeared on one of the factory roofs. This bird has a particularly broad band on P5, which would be a pro-YLG characteristic. As a sub-adult though we might expect a little more black on the wing of the hybrid as well. Through the scope the dark eye and dark marks on the primary coverts were clear - the latter are obscured in these shots, although the third (blurry) iphone-scope pic shows the width of the band.

*I am assuming that these two birds are both hybrids, rather than Yellow-legged Gulls...

Here are some shots of the adult bird from today. Seen on rooftops and in flight.

Introducing Isabel - a dilution mutation Herring Gull at Seafield

Herring Gull (centre) with dilution mutation (isabel) showing much reduced eumelanin across plumage

Seeing a white-winged gull is usually the highlight of any day's birding for me. Sunday was no exception and this time the bird was a Herring Gull, albeit one with a dilution mutation (as defined by van Grouw in the January edition of British Birds). This mutation results in a quantitative reduction of melanin - and since gulls only have one form of melanin (eumelanin) it is impossible to say whether this mutation is "pastel" (the reduction in both forms of melanin) or "isabel" (the reduction of eumelanin only).

At rest most of the plumage appeared to be snow white. Bare part colouration appeared to be normal.

This gull - let's call her Isabel, perhaps - has been reported at Seafield already this winter, but this is the first time I have seen her. Why her? Well, many of these conditions are sex-linked in birds, and since in birds the heterogametic sex is females rather than males (unlike mammals, where males only have one copy of the X chromosome), so I am guessing that it might be more likely that this bird is a female.

Massive crop, but gives a good idea of the bird in the field

I'm looking forward to closer views of Isabel at some point in the future... Here are some more flight shots - the normal grey upperparts are white and the black wingtip a nice faded grey.

The dark smudge on the underwing in this shot is a shadow of another gull.

Again, a shadow is unhelpful but the white plumage with grey on P8-10