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An odd 1w Common Gull (1 Viewer)

Dean Nicholson

Cloacal Protuberant.
Whilst grilling the Gullage near Skegness on Friday I bumped into this small and dusky 1w and honestly convinced myself i was looking at a brachyrhynchus(!)
After sleeping on it i have since lost a bit of faith and think that a dark canus could actually look like this but there are a couple of things that would still seem a bit odd for that..... firstly the size of the thing - It was only present about 2 minutes so i couldn't snap it alongside any other Common Gulls but you can compare it in size to the BHG in the first shot to get an impression - it was about the same size as a BHG and looked tiny next to Herring Gulls, It wasn't only the small size that was eye-catching either, even on a 'normal' sized CG the dark markings on the head and underparts were striking.... far darker than any other 1w canus present.... the last shot i fluked as the bird flew off (never to be seen again) shows a very dark/messy underwing with a dirty grey ground colour which is obviously darker than the uppertail covs, this is quite different to the pale/whitish looking underwing usually seen on canus? also the brown stretches right down past the legs/lower belly which i also think is unusual in canus? and the final thing that niggles is that even on dark and well streaked 1w canus they usually show an unmarked whitish throat/chin area.....
The upper and undertail coverts are certainly streaked but enough for brachyrhynchus? there are certainly some birds on GRO and other sites from America which show a similar amount of streaking but it's not too difficult to find dark end canus with similar either.... and i can't really see enough of the tail to comment.
I also think the finely fringed upper tertials are also a better fit for brachyrhynchus and i won't even go into that oddly small head and bill...
Throughout the rest of the session i payed particular attention to other 1w birds present and struggled to find any with obvious streaking to under-tail coverts or even with any underpart streaking below the upper breast sides, the underwings in flight also appeared much whiter than the subject bird too, often appearing similar to a 1w Casp.

Comments more than welcome if only to tell me i'm looking too hard!

Cheers
Dean
 

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Hi Dean,

this is safely a canus.
The underwing is far too extensively white for brachyrhynchus, the upper and undertail coverts appear too prominently white, white tertial fringes are extensive and the underparts appear scalloped rather than smoothly washed brown. The clean grey upperparts are a good feature of 1w nominate canus too.


A dark 1w canus for comparison:

https://waarnemingen.be/waarneming/view/63231656
 
Thanks Peter.... I did lean canus way in the end but thought i'd get it out there as it seemed strange to be both oddly dark and oddly small....if it was just the one anomaly i probably wouldn't have gone for a second opinion.

Your attached bird is cracker and not too far off the Skegness bird in the looks department - and i thought that tail looked vaguely familiar!... second row down (3rd along) in the DB paper on page 39 :t:
 
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