6th November 2011
Well done to the guys at Landguard Bird Observatory for adding to the ongoing data on vagrant Siberian Chiffchaffs. Will Brame sent the photos and info on the bird below. It was trapped on 6th November 2011 at the observatory in Suffolk. Nigel Odin then passed on some material for analysis to Dr Martin Collinson who was able to report back as follows:
“The cytochrome b sequence came back. There isn’t a lot of comparative tristis cytb sequence in the database (actually only 1 sequence), but this bird is almost identical to that one (1010/1012 bases the same): a tristis collected at the Mirnoye Biological Station on the banks of the R. Yenisei, Siberia. So your bird is definitely tristis and consistent with an origin in the core range of the taxon. In comparison, albietinus, nominate collybita, and the southern stuff e.g. brevirostris, menzibieri, Mountain Chiffchaffs and Canary Island Chiffchaffs are all at least 10-40 bp different, so it confirms it’s none of them. As far as we know, this is the first genetically confirmed tristis in Britain, though several have been done previously in Sweden (thanks to Magnus Hellström for information on that point). At least it reaffirms that the criteria used to identify birds on call and plumage are OK. ” [Thanks Martin!]
It was reported to give classic tristis ‘peep’ call, once upon release.
Its not necessarily exactly from here, but it’s DNA matches most closely with a Siberian Chiffchaff from here- precisely where the green arrow points– go on and zoom in…:
Siberian Chiffchaff, ‘tristis’. Landguard Bird Observatory, Suffolk, 6th Nov. 2011. All photos Will Brame. The first record from Britain to be confirmed by DNA analysis (AFAIK).
It looks the business (beware I am going to use the word buff/buffy several times ‘cos I can’t think of better colour description, though I am sure there must be one!)
Lovely brownish upperparts, dull olivey green only on wings in profile (scarcely on tail in pics). BIG buffy supercilium, reducing the appearance of the white eye crescents especially upperside one, lovely buffy wash over face, breast sides, flanks and vent. A real corker! Notice though that the bill isn’t all black– and that’s O.K!
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Interesting, especially as I found one on Blakeney Point last autumn (Oct) and at the time I noticed my bird also had similar yellow base to the soles/feet. I worried a bit that it did not fit the ‘all black’ bare parts that I thought most had. It appears this feature is also quite normal for tristis.
This is intriguing! Of the 113 Chiifchaffs I caught in Jan/Feb at three Cornish sewage works, at least 13 looked like this, showing various greeny-olive hues to the upperparts. There were then a further 8 looking much more like what you’d expect a tristis to look like, with little or no green tones at all on the upperparts. Many (but certainly not all) of these called like a tristis as well…
Like Sacha, I found one at Spurn last Autumn which looked identical to this bird and did the classic peep call, but i was a bit worried about the bill colour and Martin said then that this is ok – so well done you Languard boys. We did catch a second bird but no feathers fell off!
I was under the impression from Svensson that these birds that show a yellow/green wing panel and grey upperparts that is kind of Bonelli’s Warbler like in appearance were of the race fulvescens rather than tristis. Isn’t tristis wholly pale brown with jet black bill and legs or have they changed the criteria again?? They are all Siberain Chiffchaffs, but there still seems to be confusion about what actually constitutes a tristis. Can someone clarify this please?
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