Monday, September 21, 2009

19th September 2009: Teluk Air Tawar, Penang

I went back today in the hope of getting better pictures of the juvenile Little Stint seen yesterday, but I couldn't see that bird today. Instead there were at least two adult Little Stints, now largely in non-breeding plumage.




















I'm not suggesting the bird is identifiable on this view! The lesser coverts, two scapulars, the primaries and rump feathers are all old and worn, and the tertials are missing altogether. With a bird in this kind of intermediate plumage, it is really important to try to get a good view of both sides of the bird, as the odd unmoulted feather on one side or the other may be the key to resolving its identity.




















In this case, there are no tell-tale chestnut fringes on any of the old feathers on the left side. However, the bill is long and finely-tipped, and the head looks small, both good features of Little, as is the upright stance. The dark-centred non-breeding scapulars look good for Little, although this is no more than a supporting feature. On average, Little has darker-centred scapulars than Red-necked in non-breeding plumage, but there is so much individual variation in both species that this can't be considered a useful diagnostic feature.
























This blurry picture shows the typical upright 'jizz' of a Little Stint. The legs on this bird don't look particularly long, though this may be partly the effect of the bird fluffing out its belly feathers.

One of the problems with trying to identify birds from still photos is that it's a completely different process from identifying birds in the field. With a photo you can go through a checklist of discrete features, count the primary tips, measure the bill, etc, but in the field I find that almost all of my identifications are based on a kind of instant recognition borne of familiarity. A possible illustration is the difference between recognising my daughter when she comes out of school dressed in an identical uniform to hundreds of other students (field id), and trying to describe her features from a photograph. All this to say that, if telling a Little Stint from a Red-necked from photos seems difficult, go out and spend many hours watching Red-neckeds and it should be easier in the field!






















The central rump feathers are old breeding feathers, still showing quite bright straw-coloured fringes. Grant and Jonsson's classic paper on stint identification mentions rufous fringes to the rump feathers as being diagnostic of Little. Pics of some breeding plumaged Red-necked Stints here , here and here indicate how little colour is found on the rump feathers of Red-necked in breeding plumage.


















This second bird was easier because it retained more old breeding plumaged feathers - a complete set of brightly chestnut-fringed lesser coverts on the right hand side (no photo sadly!), and, less obviously, on the left too, and some old greater coverts and tertials, both with traces of bright chestnut fringes. Chestnut-fringed tertials aren't particularly helpful, as breeding Red-neckeds often have one or two, and, exceptionally some chestnut fringing on the inner greater coverts too (see here), but mid-position greater coverts with chestnut fringes should be a good indication of Little.




















Another glimpse of bright-edged rump feathers.






















Where did those bright mantle feathers come from?! It was quite surprising how, when the bird was relaxed and the feathers fluffed out, suddenly more of the old breeding feathers on the mantle and breast sides became visible. Both these birds had a nice long primary projection beyond the tail tip.



















For comparison, here's a Red-necked Stint at a similar stage of moult. Note the complete lack of colour on the coverts, the lone old lower scapular, 'tiger-striped' orange and black, and the short legs.



















Another adult Red-necked in crisp fresh non-breeding plumage. The primary tips on this bird fall short of the tail (though this isn't invariably the case).













Five adults with a juvenile. The bird on the right is a longer-winged individual.





















































A few different juvenile-1st winter Red-neckeds, showing some of the considerable plumage variation. Compare the last, strongly-marked individual, with yesterday's juvenile Little Stint.


















This one lacks any gingery or brown tones. I do wonder how easy it would be to pick out a Semipalmated Sandpiper amongst this lot!
























It's worth clicking on this one to enjoy the detail in the larger image! This is the same individual as the first of the four juvs shown above.


















I got my daily dose of Broad-bills! A juv moulting into first winter plumage...




















...and an adult. Interesting how the more recently moulted greater coverts and tertials were noticeably paler than the scapulars and mantle feathers.



A juv.

















Showing that distinctive blackish leading edge to the wing.





































A couple of similar but not identical juv Curlew Sandpipers.



One more. The gunshot sound in the background was a firecracker celebrating the end of fasting month. They went off regularly throughout the day, which is probably why the birds were so laid back about it! Keep your eye on the sand plover just to the left of the Curlew Sandpiper...!




















And a much more richly coloured bird, with a surprise juvenile Sanderling two birds in front.




















There are still a few adults about with some breeding plumage.






















But most have already moulted into non-breeding plumage by now.
















In addition to the stints, there were some interesting sand plovers around today, including this Greater (right) with some remnants of breeding plumage remaining.






















But it was the Lessers that were really interesting. Check the length of the bill on this one! And it had yellowish legs too! Nevertheless, the bill shape makes me sure it was a Lesser - not deep-based and with a culmenary bulge on only the final third of the bill (cf the Greater above). It would be very unusual for a Greater to show this much breeding plumage at this time of year, and very typical for a Lesser.



























Another shot of the same bird, with a more typical Lesser in front, and an undoubted Greater behind facing the camera.
























Compare the bill of that bird with this one! Two extremes or different races?





















Another longer-billed bird.






















And a shorter-billed one. This bill is rather parallel-sided and has a narrow base.





















Whereas this juv has a more tapering, deeper-based bill.








































As does this adult. Despite the variety of lengths and thicknesses, the final third culmenary bulge seems to be a constant feature of all.























A lucky shot - fairly sharp and without other birds around it.



















Another variation of both Greater and Lesser Sand Plovers is that you get the odd bird with a more or less complete white collar, never as clearcut as on a Kentish, but certainly enough to make you wonder, especially as it shouldn't be there, according to the books!.

















The reason I didn't get better shots of some of the birds today was that there was lots of disturbance. A couple of House Crows regularly bombed the birds, and the construction site workers came to set up a crude trap to try to catch some of the birds (unsuccessful, happily). Most amusing of all was the sight of a goat cantering through the flock, followed by an increasing number of workers in hot pursuit. The goat vanished into the long grass behind the roost site, and the workers seemed to be unsuccessful in resecuring what was undoubtedly intended to be the main ingredient of their Aidilfitri meal to celebrate the end of the fasting month tomorrow! Too bad that incident also put paid to the wader roost for the day!























A quick detour to Kubang Semang got me brief but close views of a 'non-Common' snipe - either Pintail or Swinhoe's. The uniformly fresh plumage indicates that the bird must be a juvenile, but which one?






















Fortunately, the bird stretched its wing and tail, enabling me to glimpse some of the outer tail feathers. Unfortunately, the position of the spread wing obscured the diagnostic outermost feathers. According to the photos in Paul Leader and Geoff Carey's paper on snipe identification in British Birds, Swinhoe's outer tail feathers start to get progressively narrower from about the third pair out from the central feathers, whereas on Pintail, the central four pairs are evenly broad, and then the rest outside of those are abruptly pinlike, with no gradation between the two. I think what I can see on this pic is a gradual narrowing of the outer feathers, which would make this a Swinhoe's Snipe.














































Other features supportive but not diagnostic of Swinhoe's are the position of the eye, well back in the head, and the wingtips falling well short of the tail-tip.

I'd appreciate any comments on the ids of sand plovers, stints and snipes in this entry!

3 comments:

Terence Ang said...

Dave,

I was at this site at high tide but I've got zero wader. Not too say I almost got stuck. Didn't really thought the road will be that bad though I've been warn by you. Will try again next week.

Gyorgy Szimuly (Szimi) said...

Hi Have,

I have created the account for you but not sure where to send. Please, provide me your e-mail address.

Szimi

Anonymous said...

Hi Dave,
Liked your photos, particularly the Swinhoe's Snipe. Regarding the ID of Pintail & Swinhoe's, the literature doesn't back up my field experience. Swinhoe's to my eyes are paler & yellower than Pintailed (which is a very dark bird & can be confused with Common Snipe on the ground)& when flushed call, a distinctive, crap! Pintailed when flushed, calls a bit like a Marsh Tern. Both very different calls. Plenty of experience birders say these species are very hard, if not impossible to tell apart in the field. I am confused by their views, as I find them to be different!
Cheers
Steve James