Friday, January 14, 2011

ID hell, episode four - another SNR Gull, December 2010

Another one from the local patch (Stoke Newington Reservoirs), from a couple of weeks ago, on 28th December 2010; found amongst a large build-up of the commoner gull species on the ice of the East Reservoir, quite late in the day and in overcast, dull (and very cold) conditions.

At some distance (the short films here are with the scope at 60x and a hand-held pocket digital camera at full zoom), the bird still stood out conspicuously. Confusing features included:

overall size and shape - slightly smaller than nearby Lesser Black-backed Gulls, with a lower carriage; probably also slightly sleeker and less bulky than e.g. graellsii;

head - relatively small and fairly rounded, with a gentle hind-crown peak; dark streaking intense immediately around (esp. just behind) the eyes, but otherwise light and inconspicuous

legs - pink; appeared quite short

eye - pale, perhaps yellowish, iris; quite 'mean-looking' despite apparently diminutive features

bill - also appeared quite short, almost blunt, with little gonydeal angle; yellow with large red gonys spot

Upperparts - mid/dark grey, darker than e.g. argentatus and michahellis (and slightly darker than Common Gull); clearly paler than graellsii

wing detail - the most striking feature in the first instance and throughout - very extensive white primary tips, which formed an almost unbroken white line along closed primaries from a distance; large white tip to p10, seperated from large white mirror by a small dark band; extensive white trailing edges to remiges; large, extensively white tertial step

After a bit of research on and offline, I'm still unable to find anything like a worthy mast to pin its colours to. Comments, as usual, welcome.