29 July, 2010

I'm not sure what to say....


Since my last post, some stuff's happened that has left me feeling.. well, I can't even put a proper word to it. I've not blogged since, as every time I've started running through a new post in my head, it goes wandering off to places unpostable...

Before I get onto that, I'd better update my doings; Not a lot! I've been pursuing jobs diligently, and bashing the patch and interrogating the local Herrings until they say 'Uncle!'. I got singed by the sun yesterday. Er.... Oh yeah, the rubber rainhood on my li'l scope's expired [it was a fancier one, and lasted almost a whole year... Grr] so I've found a metal one - its a bit short but after I added my custom armouring* it should do the job. Got it second hand from the wonderful Mifsuds [they deserve a plug] for 1/9 the retail [as new condition]. Next time you're in Brixham, pop in and have a browse - check out all the proper cameras they have...

*Li'l scopes, being made of plastic, and quite thin plastic at that, may split in two if dropped [though apparently if you stick them back together they still work fine - the prisms are held securely]. Being paranoid I've applied homemade armouring to the prism housing - layers of packing foam, duct tape and black electrical tape - though due to wanting to keep using the Grippa Case, I've not been able to cover all of it, so when on the shoulderpod it looks really weird...

Right then.

So, there was this gull. When I saw it on Saturday, everyone was happy with it. I suffered a touch of paranoia about the gonys, but on getting home I checked the bill morphology and saw that, yes, it was fine. Job's a good 'un, right?

Only people [who will remain nameless] had taken photos, and on looking at them saw something different to what was seen at the time. Could this be in fact a Yellow-legged? Photos were posted online, and people who hadn't seen the actual bird, and only had said photos to go on, said indeed it definitely was. By this time the bird had done a bunk, and I was left cursing not having taken more notes than I did - but back then the ID was secure and I had a teen-lister who wanted feeding [deary me..]

A very kind [and very nameless] gull expert of the proper scientific kind has sent me a paper on Caspians, which is very long and detailed and if I remember rightly says that you can only 100% ID them [ie. juvenile Caspians] by call and threat display. This is unfortunately of no use when the gull is resting, bathing and preening in a quarry and thus staying silent and not threatening anybody... From what I learn, it seems every other juvenile Caspian feature can be shown by Yellow-legged. Yes, even the white in the underwing. Possibly the blotchy boa too, though they were a bit vague about that one. I find this very inconvenient, and would like to know to whom I can complain! ;)

What I didn't learn is if any Yellow-legged can show ALL of the potentially shared features....

[[After all, Herrings can show all of the Yellow-legged Gull features, {I've seen three this week alone with more than one each} but never all of them at once]]

I am thus requesting that all of you who are reading this, ESPECIALLY if you saw the gull, to please comment and tell me why exactly this is a Yellow-legged and not a Caspian.
I am genuinely very curious about this - you cannot seriously ID a bird by jizz alone, there have to be criteria - thus there has to be something I'm missing.

2 comments:

  1. Hi Tom. Perhaps you don't subscribe to BB, but you may be interested to know that an excellent Casp ID paper (by Chris Gibbins, Brian Small and John Sweeney) was published in March this year. Or perhaps this was the article that was sent to you? Anyway, it was 'part 1' - dealing with 'typical' birds. Part 2 is due for future publication, and will deal with the ID of less typical individuals and hybrids.

    For what it's worth, my own experience with big gulls is that they can mislead you horribly. I would guess that a bird which shows ALL the features of Caspian Gull can only be a Caspian Gull. The further away from 'ALL' you get, the less likely it's a Casp. Though (up to a point) it still could be...

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  2. Hi Gavin. Thanks for your comments! :)
    Yup, the BB article was indeed sent to me by 'Very Kind Expert Who Shall Not Have His Reputation Sullied By Appearing On My Blog'..

    I'm right there with you on the sneakiness of big gulls. The thing that's driving me a little nuts is that the features which have been touted as 'pro-Yellow-legged' in this bird have all been shown on birds identified by, er, 'Various Nameless Experts' as Caspian.. Doesn't prove the bird was Caspian, but does knock a hole in the Yellow-legged ID. :-/

    After a lot of thinking and research, I've decided to de-tick it and put it Under Question until I can decide exactly what makes a Caspian Gull. Unless anyone has any thoughts?

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