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Sunday 24 January 2021

Lovely 2w Caspian Gull

Over recent weeks the Axe has been blessed with good numbers of gulls, both big and small.  But no quality within them, even though every time I have gone through them I've been fully expecting to jam into a white-winged gull of one flavour or the other.  

Well still no white-winger, but a lovely, and I do mean truly lovely Caspian Gull, that spent the best part of 45 minutes outside my office window late this afternoon...

Hunched up but striking as always

The above was my first view of it.  Well actually I suppose technically it wasn't, because about thirty minutes earlier I was convinced a 1w/2w Casp flew past my office window heading upriver, but as it was a naked eye only view I couldn't be sure.  

Flight view aside, it was 15:30 when I scanned through the small gathering of gulls on the lower Estuary (about forty birds) and this beady eye on a clean white head stopped me mid-scan.  After a minute or so of studying I noted light brown flank spots and chevron markings, a darker grey mantle than surrounding Herrings, plain greater coverts, narrow bill (albeit not at all long) and after a quick flap a lovely white uppertail with broad black tail band and ice white underwings.  The Axe's first Casp of 2021 - but what age?

My immediate thought was second-winter with that pale bill, but the upperparts weren't as advanced as you'd expect (not that much grey and much more brown) for a second-winter Casp in January.  So I started veering towards first-winter, but an open wing shot clinched it.  A second-winter bird (3cy) it was thanks to the single white mirrors on P10 of each wing...

Horribly over exposed, but see the little white dot just down from the tip of the outermost primary feather on each wing

Here's a few more shots of it, some taken in flat dull light others with a hint of sun on them...

Love those chevron type markings on the lower flank, and look at that tiny dark eye

Best shot I got of the tail

Bill still looking unremarkable but see how white headed it is compared to every other gull in shot!

And to the bill, it may not be long but it is narrow and parallel.  Check out the goyns angle on that ad/near-adult Herring (the angle along the lower edge of the beak where the red spot is) and how curved the bottom edge of the lower mandible is. Compare with the Casp behind.

Despite it's fairly delicate/reserved structure for a Casp, now and then when it became aggressive or was excited by something, its neck would shoot up like a giraffe and strike a very typical Casp-pose!  You'd be forgiven for thinking this was a different bird!

I can't reiterate enough just how distinctive (I'd almost say unique)  that grey-brown necklace is for a young Casp. Extends around the back of the head and part way down the neck sides, contrasting so strikingly with the white head and breast. Sometimes it can form a complete necklace but most often it doesn't meet in the middle.

At about 16:20 part of the flock took flight, and although some landed again sadly the Casp didn't.  Hopefully it will hang around though, I for one would love to see it again, such an interesting example of a second-winter Casp.  

This is mine and the Axe's fifth second-winter Casp, I've been lucky enough to have found them all.  I am still waiting for an older bird though - and with all the adult Herrings now developing clean white heads as we head towards spring, I feel that's become a bit trickier this winter.  

From my records this is the Axe's 23rd Caspian Gull, my 14th.  For anyone interested, maybe there's one or two of you, here's my Axe Casp spreadsheet showing all Axe records. For long-staying birds the month listed is the month it was first seen...



I wonder what 2021's final tally will be? Will it be greater than four? 

2 comments:

  1. A lovely Casp, that one Steve. And good to see the spreadsheet too. The Axe has been well blessed with those excellent gulls. 😊 👍

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    1. Thanks Gavo! Really was, a real chameleon in terms of structure too, sometimes looking small and delicate but then looking so tall and just oh so Casp!

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