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        Discussion Area 討論區 >> Bird Identification 鳥類辨識 >>  Chinese Bush Warbler(?)
        
(Message started by: Griffin on Oct 22^nd, 2003, 10:20pm)

Title: Chinese Bush Warbler(?)
Post by Griffin on Oct 22^nd, 2003, 10:20pm

Subject: Chinese Bush Warbler(?) Female(?) Cettia canturians
Location: KFBG
Date: October-18-2003.
EOS 10D, EF300mm f/2.8 L USM, EF2x II TC, f/8, ISO400.

We encountered this hungry little bird on our way down. It was too busy feeding itself so we can get some what "close". Nonetheless, the photographs below are cropped >50% and are definitely of no artistic value.

Thanks for viewing.

http://www.pbase.com/image/22554727.jpg
http://www.pbase.com/image/22554728.jpg

Griffin.

Title: Re: Chinese Bush Warbler(?)
Post by Albatross on Oct 23^rd, 2003, 8:47pm

Hi Griffin,

Would you mind to tell why you suggested they are Manchurian (Chinese) Bush Warblers?

AB

Title: Re: Chinese Bush Warbler(?)
Post by Griffin on Oct 23^rd, 2003, 9:05pm

Just wild guess. :D That is why I leave a question mark. I would be grateful if you could give me an idea.

TIA.

Griffin.

Title: Re: Chinese Bush Warbler(?)
Post by miket on Oct 24^th, 2003, 9:01am

This is a not Manchurian/Chinese Bush Warbler Cettia canturians (officially referred to in HK as Japanese Bush Warbler Cettia diphone), on the basis of general coloration, amongst other things - richer brown in JBW, with a distinctly browner crown, usually.

What it is, I think, is a phylloscopus warbler of the Dusky/Radde's/Yellow-streaked group. Since we record hundreds or thousands of Duskies for every Radde's recorded and about 100 times that for every Yellow-streaked, and since there has been massive passage of Duskies through HK in the last ten days or so, you have to look for something to suggest they are not Duskies.

Actually, what we can see of supercilium shape (broad + diffuse in front of the eye, fine and well-defined behind the eye) + bill depth + impression of greener tone to plumage (classic features), + duskiness below, suggestion of pale panel in wing (things I've frequently observed) suggest this may well be a Radde's Warbler P. schwarzi. Legs look strong too, but you'd expect to see rusty-buff undertail coverts, which this bird doesn't seem to have.

Did you note a call? This is crucial.

Having said all that and looked again at picture 2 it has occurred to me that it just could be a very worn Arctic Warbler, but it seems very unlikely from Pic 1 - I assume they are the same bird.

Mike Turnbull

Title: Re: Chinese Bush Warbler(?)
Post by Griffin on Oct 24^th, 2003, 2:50pm

Thank you for your kind help.

Both pictures represent the same bird as we are tracking it all along.  I need some more time to "develope" more photographs of this one which, in a hope, to provide more information which leads to generation of a positive identification.

BTW, IIRC, there was no call.

It would be great if other members of that trip to KFBG could contribute more information.

Regards,
Griffin.

Title: Re: Chinese Bush Warbler(?)
Post by miket on Oct 24^th, 2003, 7:06pm

Subsequent to my earlier posting, I was able to remind myself very well indeed of what exactly Radde's Warbler looks like when I had superb views of one at Mt. Austin this morning, and as a result I'd tend to say the photos are not of a Radde's - the super behind the eye is longer and finer, I don't think they usually show this pale throat effect, and the buff undertail coverts would be visible. My feeling now is that this is a Dusky, but I look forward to seeing more photos.

Title: Re: Chinese Bush Warbler(?)
Post by Griffin on Oct 25^th, 2003, 8:46pm

Here are two more (sorry, they are not in HKBWS dimension)

http://www.pbase.com/image/22628754.jpg
http://www.pbase.com/image/22628755.jpg

Again, they are not clear enough (especially colour) for I did not use any flash at all.

Griffin.

Title: Re: Chinese Bush Warbler(?)
Post by Mike Turnbull on Oct 26^th, 2003, 8:31pm

Yesterday, Saturday, I saw two more Radde's (calling all the time) at Sha Lo Tung, which sort of reminded me how exceptionally fresh and "yellow/green" the bird I saw at Mt Austin on Friday was. I've also taken the opportunity to look particularly closely at the Dusky's which have been hopping around on my lawn during this peak passage period. As a result, I'd go to back favouring Radde's, on supecilium shape in the first photo, and maybe super. length in the second, and on apparent "jizz" in the second. I'm afraid the additional shots don't seem to add much.

Personally I'd suggest you submit as a Radde's attaching the first two photos.

Mike Turnbull

Title: Re: Chinese Bush Warbler(?)
Post by Mike Kilburn on Oct 26^th, 2003, 10:05pm

Dear Griffin and Mike

Just make matters more confusing I have to say taht I agree with Mikes initial assessment that this is a Dusky Warbler.

Why?

a) The overall tone of the bird looks rather grey-brown instead of yellow-green.

b) The shape of the bill - in your second photo is looks short but on the others it looks longer. However on neither pic does it look as if the upper mandible is srongly curved, as Radde's often shows.

c) In the last picture especially the legs look rather skinny to me

d) The undertail coverts look rather pale

Its also worth remembering that most species (including some phylloscopus warblers - aiya!) do show lots of variation or abnormality and can be just about impossible!! Best is to keep looking at them, accept that some will escape from a firm idenification and and after a few years of practice more and more look typical and the odd ones and different species really stand out!

Please note that I add my comments in the hope that we an all learn something - it would be great to get more comments.

Cheers
Mike K