Alan Dalton post's birding diaries and original artwork from Sweden. Established in 2006, this now long running blog is now a complete overview of my birding experiences. As an artist I greatly enjoy sketching birds in the field and you will find a wide selection of that work here, from fieldwork to finished paintings. I am very passionate about my artwork and try to depict birds in their natural habitat, as I see them in the wild. My artwork is for sale and can be viewed at http://www.alandalton.net/
As regards to my photography, since 2008 I have used a Nikon D90 DSLR camera coupled with a Sigma 150-500mm OS lens for since March 2012 for bird photography, all previous images being digiscoped. Regarding sound recording, I have been usung a Telinga Stereo Dat Mic and parabol to record birds in the field, coupled to a Marrantz 661 digital recorder, a superb piece of kit. Interest in butterflies, dragonflies and damselflies has recently seen the accquisition of a Sigma 150mm macro lens. I hope you enjoy the blog and please feel free to leave comments or contact me at alandltn@gmail.com

Monday, August 08, 2011

Lesser Black-backed Gull, race graellsii/intermedius/heuglini? Skeppsbron; 8th August 2011

 First impressions of a larger, heavier bird than nearby Baltic Gulls, with an obviously paler overall tone to the upperparts. Less attenuated rear end and pot bellied apearance.


 The bird in front of me, note the dark, slate grey upperpart tone. Above a detail of the folded primaries.Note also the old worn primaries(p7-p10) with small, but distinct mirrors. p6/5 appear to have been dropped, exposing a white tongue on the inner web of p7. A large mirror is apparent on p10. Rather large billed, note the red gonydeal spot is confined to the lower mandible. The bill is fairly long and paralell sided, the gonys not very angular. Legs pale yellowish. Moult is apparent on the haed and gives the bird a slightly ragged appearance in profile...




 Direct comparison with Baltic Gull. Head larger, with slightly less rounded head with slightly flatter crown.. A generally bulkier bird with less attenuated rear and more pot bellied appearance. Note the lack of white on the longest scapulars and the small mirrors on the primaries...




 A decent shot of the bird at rest. A good view here of the primaries, note the whitish tongue on the inner web of p6. In many ways the birds build reminded on of Herring Gull rather than Baltic Gull.




Direct comparison with Baltic Gull, very obviously not as dark on the back as nearby Baltic Gulls...


Shots here of a Lesser Black-backed Gull, of as yet indetermined race, from this morning at Skeppsbron.

Edit; Spent the early part of yesterday looking at Baltic Gull(Larus fuscus fuscus) at the same site, in particular primary moult and any sign of it. A total of just 8 adults were seen sufficently well to assess primary moult, which admittedly is not a large sample of birds and may not allow for variation. On average these birds showed old, worn outer primaries intact and unmoulted. On closer inspection some birds showed new primary P1, on one bird both P1 and P2 were new. Dropped primaries were seen as far as P4 at most. So it seems these birds are later to moult in general than the bird here, which has dropped primaries P6 inwards, though yet shows no sign on the folded wing of new primaries...
In addition. of the majority off Baltic Gulls viewed on the deck, about twenty individuals, showed rather uniformly blackish primaries, often with a prominent white tip to P7 only. Just two birds showed very small white dots on the tip of P7-P10. None showed even, larger white tips such as those on this bird. Wear on the outer primaries was also noticably less in Baltic than observed on this bird, which when all is taken into account tells me this bird is of one of the lighter manteld races within the Lesser Black-backed(fuscus) group, the question is which one?
Coming from Ireland I can say that, on reflection, I have never seen such a dark mantled Graellsii. A suspected graellsii at this sight last year was much lighter toned. I am not familiar with intermedius or heuglini, but would add that any race other than Baltic gull is rare in Stockholm. Anyone help shed some light on primary moult of intermedius/graellsii in august? Having spent time observing thses birds over the past few days I find myself intrigued, if even more confused, any pointers would be welcome, even if seperation of say intermedius/hueglini is deemed impossible on current understanding.
With regard to range I would consider Stockholm would be more loikely to receive intermedius than heuglini, however given the amount of heuglini suspected in Finland over the past few years Stockholm could well be receiving this race in small numbers, perhaps on or two at least anually. Given the difficulty in detecting these birds at all it is probably conceivable that they are regular on the baltic coast of Sweden?
Wishful thinking perhaps, but these are the thoughts running through my head as I look through these birds over the past few days

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