Thursday, 7 April 2011

Gull sp RSPB Conwy

Any one got any opinions on this gull photo taken at RSPB Conwy on Tuesday over the high tide.

























Alan and Ruth


www.thebiggesttwitch.com updated today with blog about ydays Purple Heron - still present this evening.

11 comments:

  1. Interesting Gull Alan. Looks like a 2cy Yellow legged Gull to me. However, certain features don't quite fit but even these could well be within the norm for michahelis.
    Pro-points include the thick all dark bill with a deep gape angle, dark smudge around the eye, long legged appearance, pointy looking primaries, general bulky look, moulted grey mantle feather colour and general white headed appearance.
    On the negative side the peaked look on the second photo is strange (almost Caspian), but does look completely different on the first photo. Secondly the tertials look very white edged for 'michahelis', but are presumably very worn.
    Interesting bird - wish I'd seen it.
    Where's Pete Kinsella when you need him.......?

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  2. Hello Alan and Ruth, good to see that the gulls are getting scrutinised in North Wales!It`s quite a striking bird this isn`t it? with several seemingly conflicting features which makes ageing( always the first step) tricky.It has a virtually all dark bill like a first year, but on closer inspection seems to have a pale iris of a second year.The mantle has a mixture of lead grey second year feathers and brownish first year feathers.the wing coverts however don`t seem to have any new, grey second feathers admixted with the worn, faded , first year feathers.So it`s either an advanced " first summer" or a retarded " second winter", probably the latter.
    The darkness of the grey on the mantle suggests its not an argenteus Herring Gull, but either a Lesser Black-backed Gull, a Yellow-legged Gull or a Scandinavian Herring Gull.I would dismiss the latter because of the extensive black on the tail and rather long-legged, long-winged jizz.The extensive black on the tail, although difficult to discern and the dark based, white tipped tertials could fit both LBB or YLG.The head shape, sleek and rather snouty would point towards LBB, it lacking the bulbous forehead of YLG.But this head shape could be affected by the birds mood.
    The birds size looks different in the two pics, big in the close up and smaller and sleeker in the more distant shot, so maybe this is a case of "size illusion".So all-in-all a tricky bird and probably one that looked less confusing in the field( analysing pics is fraught with danger!!), but I would say its a Lesser Black-backed Gull,
    cheers, Pete.

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  3. Cheers Pete.
    Always learning....... :-)

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  4. Hi Marc, it`s a really interesting bird this( for anoraks like me anyway) and my opinion is of course just that, as I said analysing pics is tough sometimes and often one person`s perception of an image differs massively from another viewer`s.The bird in question could be a YLG, the jizz in the two pics looks very different ,don`t you think? Sometimes you have to go on a gut instinct, I`m sure you`ll agree when you`re catching glimpses of fast moving migrants up on the Orme! Mine is for a LBB, but more pics would be good, especially any open winged shots.
    cheers, Pete.

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  5. Having had a look at this on a camera and then an Iphone, I felt that it showed features of YLG. These still appear to be there, namely the size & bulk of the bird, the shade of grey on the upper mantle, the leg length (in one of the photos but not the other!), spiky primaries and the bill shape. The odd feature is clearly the head shape, with a Casp-like feel in one of the shots, less so in the other (I don’t think it’s a Casp btw). This head shape is probably within the potential variation in YLG, but there is something about the head shape in the shot where it’s behind 2 other gulls which is very LBB-esque; something to do with the chin area I think, between the bill and throat. I must admit that when looking at the photos on the camera, I thought about the possibility of LBB, but dismissed it due to its’ size, jizz, posture and the mantle colour. If it is a LBB, it’s a monster; I’d be interested in comments as to whether the adult mantle feathers are or aren’t too pale for LBB?
    I discussed with CJ whether it was a first- or second-winter, as it seemed to have a lot of adult feathers for a FW, and not enough for a SW! I think I plumped for SW, but I can see how it could be a FW, esp if it were a YLG as they do moult early; could this be a pro- YLG feature on this bird? If it’s a LBBG, would that make it a SW?
    B interesting to hear from AD what his field impressions were, particularly the shade of the adult mantle feathers, as this is very hard to assess in the pic without having a LBBG standing next to it. As I’ve said before, photos can be very misleading!
    I wonder if the bird is still there…
    Cheers, Michael James Duckham.

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  6. Very sure the same bird was there this morning. Got more pix but can't post until later.

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  7. Interesting stuff. I've looked closely at LBBG's today and can see your point about the head shape (and chin area)- the colour of the adult type mantle feathers still intruige me though. Mike and Pete, your gull knowledge is certainly inspiring and makes me realise my inadequacies in this area - keep it up.


    Next winter, I'm certainly up for a North Wales birders foray into the North west or further afield for some gulling. As Mike said in the pub last night - it would be great to be able to bounce ideas off each other and discuss features while watching real birds rather than looking at photographs. Perhaps Pete could join us and be our gull guru for the day?

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  8. That's a great idea Marc. TBH i'd love a sesh at Seaforth, not been there for a v long time, and they've got civilised things like hides!!
    Wonder if Pete could get us a day pass....

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  9. Hi all,
    First off, any shots showing the spread wing and tail? These could be really helpful, even if of relatively poor quality.
    With regard to ageing, I would lean towards 3cy: the tertials really don't look ideal for retained juvenile feathers, with respect to their pattern, even allowing for wear. The apparently pale iris also supports 3cy. As such, the general whiteness of the head and body feathers would not necessarily support michahellis, though, of course, it would not rule against it either.
    I do recall that the first 'adult-like' grey mantle/scapular feathers on graellsii LBBG can often come through paler than the equivalent feathers on older birds, so I wouldn't let the apparent tones of these feathers here lead me to exclude that species. The lack of grey coverts, or adult-type innermost tertials, would be (slightly?) atypical for YLGU in April...most 2nd-winters that we had here when Youghal dump was more productive had adult-type innermost tertials by January, and had probably moulted these in some time in the previous autumn. I'm not as confident about excluding argentatus on (apparent) structure just based on these two images, but I do agree that the most likely solution is a 3cy graellsii LBBG, presumably a male on bulk. A shot of the open wing could decide this...

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  10. Hi, well I`m sure access to Seaforth could be arranged but gull-wise it wouldn`t be that good.THE place to go gulling in the NW is Richmond Bank, near Sankey in Cheshire.Over the last three winters ,I ,along with others, have checked out the gulls here ( often 20,000+).Over 20 Caspian Gulls have been recorded in that period along with c20 Icelands and c10 Glaucous Gulls.Two Ring-billeds, a Kumlien`s and many Yellow-leggeds have also been recorded.We don`t start checking again until the end of November( too many other birds to see during the rest of the year!) and the best period is normally February-March.Feel free to contact me next winter when visits up onto the tip will hopefully also take place.

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  11. Yep i'd agree, RB is deffo the best place for gulling; i've been going there since the mid-90's, but haven't been to Seaforth for absolutely yonks!

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