Siberian Chiffchaff – The Edges of I.D.

Call and Plumage Variation

by Martin

A quick post by way of advance notice and apology. I have been working on a piece about Siberian and Common Chiffchaffs. I posted it ‘privately’ to facilitate excellent input from others, expecting to publish soon after. Then I got distracted.

Even greater variation in calls

In the course of reviewing material I revisited a fascinating Siberian-type Chiffchaff recording in Shetland in October 2010. This bird gave an amazing range of calls from rather typical tristis -like ‘peep’ to ‘swee-oo’ and ‘hweet’ calls just like western Common Chiffchaffs (nominate collybita). It looked like a tristis. Turns out I am not the only one to have recorded such a confusing (and enlightening) range of calls emanating from the same bird.

tristis 4presumed Siberian Chiffchaff, Halligarth, Unst, Shetland, October 2010. The range of calls uttered by this bird engendered new questions and new information, alongside other call variants recorded in both Common and Siberian Chiffchaffs.

Even greater variation in plumage

Meanwhile a paper, published in Dutch Birding this week (vol 34 -2012- no.6) brings further revelation and may answer the questions I have had about birds like this:

valyie Chiff 10 Oct 2012possible Siberian Chiffchaff, Valyie, Unst, Shetland, October 2012. This elusive bird was a most striking Chiffchaff. Very grey above, with big flaring supercilium, and bright lemon yellow patch above the eye. I mooted that, had it called, it would sound ‘Siberian’ but it never obliged.

The just-out Dutch Birding paper covers DNA research on 41 Chiffchaffs trapped in the Netherlands in autumns of  2009-11. Most of these 41 were birds identified in the hand as not typical nominate collybita– some being identified as tristis and others as abietinus.

Critically all birds identified as abietinus (using the kind of characters most of us might similarly apply) were found to be tristis based on DNA (as well as all the obvious tristis). This will dramatically change the understanding of Siberian Chiffchaff occurrence in the Netherlands.

Such new understandings of call and plumage variation will surely catalyse fresh debate on the kinds of characters which can be used to identity Siberian Chiffchaffs in W. Europe. Keeps us humble and learning.

Lots more to come including full range of sound files, sonagrams and photos in forthcoming post, once I make sufficient sense of it myself!

8 thoughts on “Siberian Chiffchaff – The Edges of I.D.

  1. Mike Pennington

    Hi Martin, you won’t be surprised to learn that these confusing birds have been around in Shetland for many years. Consequently, Shetland birders’ perception of what a Siberian Chiffchaff is has swayed back and forth for quite a while. The first time that there were suggestions that Sibechiff was a potential BB,,back in the late 90s, I wrote to BW to point out that they were far too regular in Shetland to be BBs, just basing my opinion on obvious calling or very dull birds. For a while we got quite confident with ID, then there was an autumn (2006 I think) when there were all sorts of birds around – obvious tristis giving collybita calls, even collybita giving odd calls (but maybe, on reflection not true tristis). I couldn’t ID most of the birds that autumn as they just could not be pigeonholed. I then got very cautious again, but have been edging back from the hardline (no green, no yellow except in the wing edges and a good call) partly through involvement with the Alan Dean/Lars Svensson study making me realise that at least some faint olive tones were possible in tristis. Interestingly, this autumn, there were loads of very obvious tristis (most not calling) on Unst from late October – possibly as many as 10 a day in Baltasound alone.

    Reply
  2. puffinbillyunst

    I suppose one point I’m trying to make is that Shetland birders have long known that our Chiffchaffs (and our Lesser Whitethroats) are unusual and worthy of study. This is not something new that we’ve missed, but when it was new to our eyes we had neither DNA analysis to unravel things, nor the internet to speculate on.

    Reply
  3. Sean Cole

    Hi

    It will be interesting to see the rationale on the genetics, and how tristis is circumscribable, given it is part of a cline.

    Is this described in the paper? For me, this is as important an element as the associated results.

    Sean

    Reply
  4. Graham Gordon

    A word from Scilly. For years I followed the Alan Dean ultra cautious approach to Sibe Chiff ID and I wasn’t happy I’d seen the absolute genuine article until two winters ago when I had the pleasure of two superb individuals that wintered in my St Agnes garden and which I was able to keep tabs on more or less daily from early Dec 2010 right through to March moult and song. Perfect in every way, no collybita/abietinus calls whatsoever. At the same time I was taken on a walk one day in December through Lower Moors by Kris ‘Spider’ Webb who was postulating up to half-a-dozen Sibes. Every single one that called peep had lovely rusty cheeks and an almost pinky suffusion on the flanks and looked consistently different from any abietinus. A bird watched with ARDean (who waited seven hours with his flask and sandwiches just to hear it call once!) in October the same year, only seemed to enhance the consistency of brown-buff birds and peep calls. This autumn, however, I’ve already seen several birds in Lower Moors that to me just don’t look like ‘classic’ Sibe Chiffs (i.e. slightly yellow suffusion to rump, more grey-brown than brown-grey) but are singing like perfect tristis! As I write, on my lawn on St Agnes I have three ultra-tame Chiffs that could be described as lacking yellow tones, indeed look very similar to the Lower Moors singing Sibe, yet they just don’t cut the mustard as being as unequivocal as the 2010/2011 birds. Indeed I have heard occasional collybita-type calls coming from the garden (and twice a tristis peep) without having been able to attach the caller to a sighting. There’s no sign of any brown-buff birds calling incontrovertibly. So what’s going on! I’m finding myself beginning to drift away from my safe, happy assertion from two years ago that collybita/abietinus and tristis were quite easily diagnosable and potentially very different species, to wondering whether or not we are deceiving ourselves if we think that we are going to come up with a definite answer, i.e. did an influx of Sibe Chiffs two years ago lead to widespread interbreeding with other races somewhere in Western Europe leading to numerous mixed character birds for several years to come? As a quick aside I’ve met at least three biologists around the World who have warned me not to be too quick to jump on the DNA-provides-all-the-correct-answers assumption.

    Reply
    1. Sean Cole

      Hi Graham

      I strongly agree with your last comment over genetic species circumscriptions, hence my previous post on here.

      I have had quite a lot of involvement in this subject over the last five years, admittedly in Orchids, but the rules are essentially the same.

      In the Bee and Marsh orchids, where hybridisation is rife, and in developing genera like Epipactis, the genetic differences are so small that definition or assessment of species status is a purely subjective matter.

      Although newer genetic techniques are being used now, even with combinations of analyses, there can in some cases be no unequivocal answer. I suspect that to be the case with Chiffchaffs.

      My suspicion is that ultimately, huge amounts of time spent trying to work this one out will be wasted, as you and others have discovered.

      Sean

      Reply
  5. Pingback: Siberian Chiffchaff and Common Chiffchaff: Part 1 | Birding Frontiers

  6. Sean Minns

    We saw both the birds on Unst last October.

    We found the Valyie bird a few days before your tour group turned up and it had us divided. Alas we never heard it call and in my limited experence I’ve never heard them call.

    One of our group who has ringed a lot of Chiffchaffs in Cornwall in the winter felt it was similar in plumage to a lot of birds they class as bright ‘abietinus’ as when they call it is no different to ‘collybita’.

    I’ve seen several similarly bright birds on the East coast over the last 20 years. They remained silent

    Before the research of recent years such birds would have been considered ‘tristis’ , but once it had been established that the buffier birds with their distinctive calls were in fact ‘tristris’ it blew that theory out of the water.

    The Haligarth bird fitted most of the plumage features one would expect for ‘ Trisitis’ in the 21st century.

    As Mike says the critera for what constitutes a ‘Tristis’ has vacilitated back and forth.

    The Dutch Birding paper once again throws the debate wide open again for what if at all possible are the definite features of ‘trisitis’.

    Reply

Leave a Reply