Chiffchaff ssp, Kent, Oct 29

[JCL]

Chris Collins, Dave Gandy and I saw a rather odd Chiffchaff in the moat at Dungeness, Kent, UK, on 29 Oct.

Some record shots attached. The grey-brownness of the plumage was
notable, but the apparent dark lateral crown sides (almost cap-like)and whopping supercilium even more so. CC and DG thought they saw the bird call (like a collybita) but, as the bird had its bill permanently half-open and as two collybita Chiffs in the same tree were calling away, I don't feel happy relying on it being our odd individual making the un-odd noise.

And it gets stranger... Jizz was oddly stocky and heavy, quite unlike the two weedy collybita. Behaviour was wacky too: it basically plopped from branch to branch like a vireo or Hippolais, and nowt like a Phyllosc. Yet a Phyllosc it certainly is, and, indeed, a Chiffy it certainly is. But - and here's my question - from where and what ssp?

In e-discussion with Alex Lees (when in doubt, turn to a punkbirder), we've discounted abietinus (too brown) and tristis (plenty of reasons). Alex (and I hope he won't mind me noting this) mooted Mountain Chiff because of the brown-capped appearance, a species that DG tentatively suggested at the time. (He lives in Thailand so he can be so bold.) But the yellow in the supercilium surely discounts that.

So we're back with a Chiffy and back with that question - from where and what ssp?

James

[KenM]

Interesting images.....primary projection appears to be half the tertial length!

[MichaelF]

Unless the image tones here are well off what the birds appeared to be, I'd not say that the "grey-brownness of the plumage was notable" for these - in that aspect, they're no different to run-of-the-mill breeding Chiffs up here in Northumbs. If anything, I'd say the pics are actually slightly yellower/greener than my local birds.

[norfolkbirder]

The amount of yellow and the length of the supercilium is nothing like i've seen in the UK at this time of year. The "heavy" behaviour you described immediately reminded me of ibericus but this is probably a bit farfetched considering i'm simply interpreting your description!

Will

[JCL]

Unless the image tones here are well off what the birds appeared to be, I'd not say that the "grey-brownness of the plumage was notable" for these - in that aspect, they're no different to run-of-the-mill breeding Chiffs up here in Northumbs. If anything, I'd say the pics are actually slightly yellower/greener than my local birds.

The bird WAS notably grey-brown in overall tone; quite distinct from the standard collybita present albeit not as cold as the single tristis I've seen. The 'warmness' of two images is most likely an artefact of (camera) white balance, ie the bird was in a shady tree. The image of the bird against the sky gives the clearest impression of tone as it appeared in the field.

Behaviour-wise, I omitted to mention that it was tail-dipping. But I guess all Chiff ssp do that. Given Will's post, does ibericus?

[bjm]

If this bird was unwell it may explain its permanently half open bill and its more lethargic movements. It would also possibly explain its more bulky jizz compared to the accompanying Chiffchaffs. Perhaps it was having difficulty maintaining its body temperature and therefore adopted a more fluffed out plumage in a bid to stay warm.

Based on the photos i would identify this as either a collybita or poss an abietinus Chiffchaff. To be honest i usually find the reliable seperation of these two forms to be far from easy due to the huge degree of individual variation shown by both.

[forktail]

Mountain Chiff wouldn't have those green tones, would be shorter-winged than a Chiff and would lack the green-olive edges to the remiges shown on this bird. The supercilium too, should be much paler and lack the yellow shown in this bird. It doesn't look much different from Chiffs I've seen this year and actually has rather more green and yellow tones than a few I've seen later in the year. I agree with Ben where he mentions the variation in Chiffchaff forms and the difficulty in deciding what birds are in the field. There is a brownish tone to the head that doesn't seem to be just due to raised feathers, and it looks wingy so it doesn't fit neatly into any particular box. Re ibericus, I think you'd need a lot more evidence to get any further than is available in these pics.

F.

[jamesg]

How about yakutensis Willow Warbler? I know it doesn't scream Willow, but it would explain the big wing, long pp, long bill and bulky vireo-like jizz...

yakutensis can have a strong brown wash on the upperparts, capped appearence with bold super and sullied underparts (hence the potential for confusion with Dusky for individuals that lack yellow tones), and apparently they also often have dark legs/feet.

Not 100% sure, but it seems like a good fit...?

[Brian S]

Unless my eyes deceive me, this has four emarginations so Willow Warbler is out. Is it also my eyes (or computer), but is the crown quite rufous - brown-hatted chiffchaff?

Brian S

[Alex Lees]

How about yakutensis Willow Warbler? I know it doesn't scream Willow, but it would explain the big wing, long pp, long bill and bulky vireo-like jizz...

yakutensis can have a strong brown wash on the upperparts, capped appearence with bold super and sullied underparts (hence the potential for confusion with Dusky for individuals that lack yellow tones), and apparently they also often have dark legs/feet.

Not 100% sure, but it seems like a good fit...?

some pics of pres. yakutensis:

http://www.tarsiger.com/gallery/index.php?pic_id=petro1233579976&lang=eng

http://www.netfugl.dk/pictures.php?id=showpicture&picture_id=259

http://orientalbirdimages.org/search.php?action=searchresult&Bird_ID=1820&Bird_Image_ID=15796&Bird_Family_ID=&p=3

[mafting]

Just a quick two penn'orth;

If it had a half-open bill all the time and was heavily moving from branch to branch, that suggests that it might not have been too healthy or happy. In that context, I'd be wary of inferring anything from jizz - posture, behaviour and everything else would be affected.

A bird with a gaping bill isn't a fit one.

[norfolkbirder]

Have to admit I didn't pay too much attention to the open bill part of the description. The idea that the bird is unwell would certainly explain lethargic movement. In my previous post I wasn't suggesting this bird was ibericus but simply that the description of the jizz reminded me of the species. Has anyone else noticed a slightly heavy, almost hippolais like behaviour in ibericus or am i going mad?
Plumage wise I find races of Chiffchaffs a nightmare having seen a couple of birds declared tristis types that look no different to regular collybita. Adding ibericus (a species that must be more regular than is thought given it's range and proven migration) and other subspecies (+ the potential for hybrids :puzzled:) to the equation means I'm happy to call any Chiffchaff a Chiffchaff unless its voice is obviously different.

Will

[jamesg]

Unless my eyes deceive me, this has four emarginations so Willow Warbler is out.


Good point Brian! If I was desperate I could argue that the fourth might be a pixellation artefact, but the three obvious emarginations are too far up the wing for Willow anyway. That is assuming that yakutensis has the same wing formula as trochilus (which it seems to in photos).

Re. suspect health - you can actually see that it has its hackles raised in all the pics, which would explain the dumpy appearence. Maybe it has a cold?

I'd go with poorly nominate Chiffchaff.

[Colin Key]

Hello James,

We are currently "awash" with Chiffys down here due to the exceptionally mild weather and super-abundance of insects - probably the commonest passerine at the moment. The variation in colour from lemon yellow through greenish-yellow to nondescript grey is quite amazing. There will be a mixture of collybita and ibericus but separating them at this time of year when they are not calling/singing is difficult to impossible.

I have had ibericus pointed out to me in the field, in spring (on call and song), but have to be honest and say that I could not have identified it on plumage alone.

Colin

[JCL]

Good point Brian! If I was desperate I could argue that the fourth might be a pixellation artefact, but the three obvious emarginations are too far up the wing for Willow anyway. That is assuming that yakutensis has the same wing formula as trochilus (which it seems to in photos).


Just to eliminate the ambiguity, I attach another pic which should put the emargination issue to rest.

[/QUOTE]
Re. suspect health - you can actually see that it has its hackles raised in all the pics, which would explain the dumpy appearence. Maybe it has a cold?

I'd go with poorly nominate Chiffchaff.[/QUOTE]

I had surmised that the open bill indicated ill health (it wasn't hot, so the bird wasn't losing heat...), but hadn't made the link to dumpy jizz and lethargic behaviour. This does seem rather logical. Particularly if it had flown further than 50 miles...

But I sense that Will and others are right. Thanks all for comments. Having moved back to the UK only last month, after three years in South America, it's time to relearn.