Colour leg rings unlock migration mysteries

Some birders and photographers view coloured bands on birds’ legs as an unwelcome piece of extra ‘bling’ which can spoil a good photo, or perhaps even interfere with the bird’s well-being.

This negative perception is unfortunate, as birders and photographers have a vital role to play in ensuring that those bands provide invaluable information about the birds and the habitats and sites they utilise, by reporting them whenever they see them.

Here’s a case in point. During my visits to a few sites in southern Ireland in  August and September, I saw an unusually high number of ‘colour-ringed’ birds. I made a point of photographing them as best I could (digiscoping is a huge help), and then looked around for who to report them to.

I was alerted to the website European Colour Ring Birding, and from that link, got to know Pete Potts, who was a huge help in tracking down the origins of my colour-ringed birds. Here’s what I’ve learned so far, and it’s been quite an eye-opener.

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Blue star = Roscarberry Bay, Co Cork; Red star = Tacumshin and Bannow Bay, Co Wexford; yellow spot = original ringing site; blue line = link between site of origin and site of my observations

  1. on map
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Eurasian Oystercatcher, Roscarberry, 5 Sep 2017.

Ringed as an adult while incubating on 31 May 2017 at Auðsholt, Ölfus, south-west Iceland (see rough route on the map above).

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2. on map

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Little Egret, Roscarberry, 5 Sep 2017.

Little Egret ‘DB’ was ringed as a nestling at a colony in Ardfry, Galway, Ireland on 29 May 2009, one of three ringed in a brood of three by John Lusby and Chris Benson. Despite the fact that this bird is now over 8 years old, this is the first reported sighting of this bird since it was ringed.

3. on map

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Juvenile Lesser Black-backed Gull, Roscarberry, 5 Sep 2017

23E:C was ringed as a chick  on Horse Isle, Ardrossan, Ayrshire, Scotland, on 26 June 17. This is the first report since ringing.
4. on map
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Eurasian Curlew, Roscarberry, 5 Sep 2017.

I received the following helpful data on this bird from Robin Ward. The bird, an adult male (born prior to 2015), was one of 20 ringed on 16th January 2016 on Wensley Ings, Wensleydale, North Yorkshire (SE0888).  Eighteen of these birds were re-sighted during last winter in Wensleydale.  ‘NO RW’  (Niger over Orange, Red over White) is one of the two birds that wasn’t until now re-sighted after marking, presumably because it has wintered in Ireland.

A large proportion of Curlew that breed in the Pennines winter in Ireland.  Autumn and wintering populations in northern Britain, originate from breeding grounds in Scandinavia (mostly Finland and Sweden), although some local breeders are involved.  Two of the Curlew colour-ringed in winter at Wensleydale I have subsequently seen during autumn passage on the Tees Estuary (2016) to then be seen back in Wenlseydale that winter (December 2016).

5. on map

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Adult Mediterranean Gulls 2XE5 and 2XE6, Roscarberry, 5 Sep 2017.

Ringed by Alyn Walsh at Lady’s Island, Co Wexford, Ireland. I’m still awaiting the details of the age of these birds.

Even though we know when we watch migrants that they travel great distances from all sorts of places, somehow it makes it seem more ‘real’ and extraordinary when you can say for certain exactly where a bird has travelled from. The idea of those birds all converging in one place on one day definitely added value to the visit for me.

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Bannow Bay, near Wellingtonbridge, Co Wexford.

6. on map

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Common Greenshank, Bannow Bay, 28 Aug 2017

Ringed as a juvenile on the Ythan Estuary in North-east Scotland on 18 Aug 2016, so the bird is just a year old. Screen Shot 2017-10-28 at 10.21.40 PM8. on mapleg-flag-Eurasian-Curlew_DSC01138

Tony Cross supplied the history of Eurasian Curlew ‘CV’. It was ringed (FJ10581) at a pre-breeding communal roost on the River Severn between Newtown and Welshpool, Wales on the 8th March 2016. It is also one of the 14 individuals subsequently traced to precise breeding territories. This one nests on a mosaic of sheep pasture and hay meadows  on the Shropshire/Powys border.

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Tacumshin Lake, Co Wexford.

7. on map

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Juvenile Common Ringed Plover, Tacumshin Lake, 31 Aug 2017.

Dominic Cimiotti kindly sent me the details of this bird: Your bird was ringed by me as a chick at nature reserve Beltringharder Koog (54.542550 N, 8.912648 E) in northern Germany at 9th of July 2017. It later fledged together with two siblings. Interestingly, it was the second successful brood of this breeding pair in that breeding season. We found the second nest, from which your bird originated, while we were catching the big chicks of the first brood!

Some of the German birds spend the winter in the British Isles. We already have two other re-sightings from the Wexford region in our data base: one bird was observed at Carne harbour in December 2015 and one bird was observed at Duncannon beach in August 2017.

It seems incredible to think that this bird was still in an egg in Germany two months before I saw it in Ireland!

Finally, one of a pair of juvenile Peregrines (the male) at this site was wearing a blue leg ring. Unfortunately, without being able to see the code on the ring, it is impossible to say where the bird comes from.

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Juvenile Peregrines (upper bird with blue leg flag), Tacumshin Lake, Co Wexford, 29 Aug 2017.

Some people may find colour leg rings or flags aesthetically unpleasing, but I think the potential knowledge to be gained by marking birds so that they can identified in the field individually far outweighs any perceived disadvantages, particularly when the information harvested can be fed into conservation outcomes. And, I must admit, on days when there seems to be nothing ‘good’ about, looking for colour-rings gives me extra motivation to pay careful attention to what I see, even when they are so-called ‘common’ species.

A final plug for anyone who sees a colour-ringed or flagged shorebird in Aisa; please do report it at this site http://awsg.org.au/wp-content/themes/AWSG/reportform.php. By doing so, you will be contributing to the conservation of these species and the sites they use, as well as finding out more about the marvels of migration for yourself!

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Finally, Singapore’s first Little Stints!

In Peninsular Malaysia, Little Stint has been shown to be a scarce but annual passage migrant and non-breeding visitor, with more than 140 records between the late 1980s and the present, most in the last 12 years (See Table 1).

Little Stint in Pen Malaysia

Table 1: Little Stint records in Peninsular Malaysia, 1988 – 2017 (eBird)

So, it’s a species which is long overdue in Singapore. The main obstacles to the addition of Little Stint to Singapore’s list of avifauna have, in the past, been lack of awareness of identification criteria to differentiate it from Red-necked Stint, and, in  recent years, lack of accessible and suitable areas of stint-friendly habitat.

Nevertheless, people have been looking, probably none more so than David Li, from whom I received a series of photos in September, asking me what I thought. With his permission, I reproduce my thoughts below, together with his photos.

Comments on putative Little Stints at Check Jawa, Pulau Ubin, Singapore, on 21 Sep 2017

Background

David sent me several images of a small group of waders he photographed on 21 Sep 2017, asking my opinion on the specific identity of two of the birds. He suspected that one or both may be Little Stints.

 

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Plate 1: The image shows a juvenile Red-necked Stint (left) and a juvenile Curlew Sandpiper (rear centre) with the two stints in question – an adult in post-breeding moult (front centre) and a juvenile (right).

The fortuitous presence of an undisputed juvenile Red-necked Stint with which to compare the two other stints is of great help in assessing these birds.

My View

Having studied the photos sent to me by David, I am confident that both the birds in question are Little Stints. I will attempt to provide a rationale for this opinion below by examining the shape/structure and plumage of these birds in some detail.

SHAPE AND STRUCTURE

I have written couple of blog posts on the structural differences between Red-necked and Little Stint (https://digdeep1962.wordpress.com/2013/09/14/sungei-buloh-stint-a-little-odd-or-an-odd-little/ and https://digdeep1962.wordpress.com/2013/03/07/identification-of-an-odd-juv-stint-at-pak-thale-thailand/) , from which I have lifted the following summary.

Structure of Little Stint compared with Red-necked Stint

  • Longer legs, both tibia and tarsus
  • More finely-tipped bill, not as deep-based. Often subtly down-curved and longer.
  • Smaller, rounder head which peaks at the forecrown, and slimmer neck
  • Body shape rounder, less attenuated, with rounder ‘shoulders’ when feeding, and head seems to sit on top of the body, rather than in front
  • Generally more upright posture
  • Less ‘deep-chested’ (not so much in front of the legs)
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Plate 2: Juvenile Red-necked Stint (cropped from the same image as Plate 3)

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Plate 3: Putative juvenile and adult Little Stints. Note the obviously longer legs, both tarsus and exposed tibia compared to the Red-necked in Plate 2, and the subtly different bill shape.

Plates 2 and 3 clearly show a marked difference in leg length, with both the tarsi and the exposed tibia being longer on both birds in Plate 3 than the Red-necked in Plate 2. Where comparisons are available in the other photos, this difference is consistent.

The bill profile of the birds in Plate 3 shows a more tapered bill, with a finer tip, with a subtle decurve along the lower edge of the bill of both birds, compared to the rather thick, short, straight, thick-tipped bill of the Red-necked Stint in Plate 2.

As the birds are relaxed and hunched up, the head and neck shape is not as clear on these photos as on some others. Nevertheless, the birds in Plate 3 give the impression of having a smaller head than the Red-necked in Plate 2.

The rugby ball shape of the Red-necked body differs subtly from the rounder, football-shaped body of the birds in Plate 3, and the way the head connects to the body is distinctively different – on the Red-necked, the head seems to sit at the front of the body whereas, on the birds in Plate 3, it sits on top of the body. Little Stints often seem more ‘bosomy’ than Red-necked, and this difference can be seen here.

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Plate 4: Red-necked Stint (left) and two putative Little Stints. The upright stance and rotund body shape of the two right hand birds contrasts with the more horizontal and slender Red-necked Stint.

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Plate 5: The head seems to sit on top of the body of the right hand two birds, but at the front of the body of the Red-necked

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Plate 6: The leg length difference is very clear in this photo. Note the flat back profile of the Red-necked compared to the more curvy shape of the two right hand birds.

The differences described above can be seen in Plates 4-6. It is worth noting that the adult bird is missing a couple of tertials, which makes the rear end look longer and slimmer than it would otherwise appear. The upright posture of both birds is typical of Little Stint and not often seen in Red-necked.

Plate 6 shows the typical ‘round-shouldered’ posture of Little Stint on the adult bird. A Red-necked in similar posture would have a much flatter-backed profile (See Plate 7).

Plate-7

Plate 7: Red-necked Stints, Penang, 9 September 2008 (Cek Jawa adult inserted). The difference in back profiles, and the ‘round-shouldered’ shape of the adult in the insert, are visible here.

The structural differences described above are subtle, and possibly not diagnostic when taken separately. However, taken together, they present a distinctive appearance which readily separates Little from Red-necked Stint. In every respect, the two birds show structural features consistent with Little Stint and at odds with Red-necked Stint.

 PLUMAGE

  1. The Juvenile

The following summary of plumage differences is taken from the same blog post referenced above:

Plumage of juv Little Stint compared with juv Red-necked Stint

  • Scapulars and coverts evenly dark-centred, pale-fringed . Red-necked lower scapulars tend to have a dark subterminal spot with pale base, and rather bland, grey-centred, pale fringed coverts.
  • Mantle often strikingly dark due to darker feather centres. 
  • Well-streaked breast sides. Red-necked has indistinct streaking and usually a greyish wash which extends across the breast.
  • Well-marked head, with dark ear coverts and central crown and white ‘double supercilium’. Central crown of Red-necked not strikingly dark, and sides blend paler towards supercilium, offering little contrast with it.

Plate-11-a

Plate-11b

Plate 8a and b: Juvenile Red-necked Stint (top) and juvenile putative Little Stint (below) cropped from a single photograph. The Red-necked has already replaced a few lower scapulars which are in fresh non-breeding plumage. The putative Little has dropped one or two lower scapulars but these have not yet been replaced. The lower juvenile scapulars are arrowed in red. The inner greater coverts are arrowed blue.

Of the five rows of scapulars, the lower two are of critical importance in distinguishing Red-necked from Little Stint. On Red-necked, these are basally pale, with a dark sub-terminal spot around the shaft. On Little, they are more extensively black-centred, with any pale at the base covered by feathers above them. The differences can be seen in the Plates 9 and 10 below (from https://www.britishbirds.co.uk/wp-content/uploads/article_files/V77/V77_N07/V77_N07_P293_315_A085.pdf). The lower scapulars are marked with red arrows.

Plate-9

Plate 9: Juv Red-necked Stint, Lars Jonsson. Lower scapulars are indicated by red arrow and inner greater coverts by blue arrow

Plate-10

Plate 10: Juv Little Stint, Lars Jonsson.  Lower scapulars are indicated by red arrow and inner greater coverts by blue arrow

The distinctive pattern of Red-necked Stint lower scapulars can be seen on the left bird in Plate 8, and that of Little Stint on the right hand bird.

A similar difference is seen in the pattern of wing coverts on Red-necked (a darker shaft streak, with the centres shading paler toward the edges, offering little contrast with the fringes) and Little (evenly dark centres contrasting quite strongly with paler fringes. This can be seen most clearly on the largest coverts, the inner greater coverts (marked by blue arrows in Plates 9 and 10).

On Plate 8, the Red-necked Stint shows darker and more contrasting coverts than on Jonsson’s painting. Nevertheless, the pattern of dark shaft streak, and centres shading paler toward the edges is apparent. On the right hand bird, the centres are solidly dark – blackish, with no paler gradation toward the edges, a pattern typical of Little Stint but not Red-necked.

The mantle of the right hand bird in Plate 8 is strikingly darker than that of the Red-necked on the left, which is typical of Little Stint.

The streaking on the breast sides is more distinct on the right hand bird in Plate 8, and this difference is visible, together with the richer, less grey colouration, in other photos as well.

The head pattern of the two species in juvenile plumage is strongly distinctive. Unfortunately there are no head-on shots of the Red-necked Stint, but there are several of the juvenile putative Little Stint (e.g. Plates 11 and 12), and all show the strongly contrasting dark crown and ‘split supercilium’ which are indicative of Little Stint.

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Plate 11: Juvenile putative Little Stint showing head pattern. Note dark crown and well-defined split supercilium.

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Plate 12: Juvenile putative Little Stint. In addition to the head pattern, note the fine-tipped bill structure

Thus, in all respects, both in structure and in plumage details, this bird is typical of juvenile Little Stint.

  1. The Adult
Plate-13_DSCO_43908

Plate 13: Adult putative Little Stint

As is the case in juvenile plumage, the critical feather groups to look at include the scapulars, coverts and tertials and head.

This particular bird is in post-breeding moult, with most of the mantle and scapulars already in non-breeding plumage (two breeding plumage lower scapulars remain on the left hand side), the coverts are almost entirely cloaked by these new scapulars (one or two are visible in Plate 14), the tertials have been mostly dropped, with the remaining one being so worn as to show no fringing. The head and breast still retain a good proportion of breeding plumage feathers. Thus, most of the distinctive features one would look for in an adult breeding plumaged bird are missing, making it extremely challenging to identify on the basis of plumage alone.

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Plate 14: Adult putative Little Stint

The pattern of the old breeding plumage scapulars and coverts are suggestive of Little Stint but not strongly diagnostic. Similarly, the rather obvious dark shading around the shafts of the non-breeding plumage scapulars favours Little (on Red-necked, non-breeding scapulars tend to be paler, with dark restricted to the feather shaft) but falls short of being diagnostic.

The head and body plumage offer the best clues to the bird’s identity. A bird retaining this much breeding plumage around the head and breast would also show at least a few pink feathers in the throat area, as well as some darker smudgy marks on the front and rear flanks if this were a Red-necked Stint (see Plates 7 and 15). The fact that the throat and flanks are clear unmarked white on this bird strongly favours Little Stint.

Plate-15

Plate 15: Adult Red-necked Stint (left) and Little Stint (right), Penang, Malaysia, 20 Sep 2007. Note the pink or brick coloured feathers on the Red-necked Stint’s breast and smudges on the flanks, compared to the cleaner appearance of the Little Stint in these areas.

As with juveniles, the central crown is darker and more clearly defined on adult Little Stint than on adult Red-necked (in all plumages) and there is a clearer split supercilium. This can be seen well in Plates 16-18.

Plate-16

Plates 16,17 and 18: Adult putative Little Stint, showing breastband, crown and underparts

Although the upperparts do not provide enough to arrive at a definite conclusion, the head and underparts, coupled with strong structural evidence, make the identification of this bird as a Little Stint certain, in my view.

Conclusion

As I have studied the photos supplied by David in greater detail, I have become 100% certain that he recorded two Little Stints at Cek Jawa, and I recommend that this record be accepted by the Records Committee.

 

Notes on a Vagrant Blyth’s Pipit in Malaysia. Part 2 – Moult

The opportunity to observe and photograph a known individual bird over a long period gives a unique opportunity to observe the progression of moult and the effects of feather wear. Examples of such opportunities regionally in recent years have been a first year Siberian Blue Robin in Malaysia (Suara Enggang Vol 20, No 3:3-5) and a similarly aged Firethroat at Nam Khan in northern Thailand.

Now we’ve had the chance to do the same with a Blyth’s Pipit!

Establishing that the bird was in ‘first-winter’ plumage when it was first seen on 2 Jan 2017 (see Part 1), the next moult it was due to undergo was Pre-breeding moult. A quick review from Alström and Mild:

Pre-breeding moult: In the late winter or early spring of the second calendar year, i.e. when the bird is 9–10 months old, most pipits and wagtails go through a partial pre-breeding moult to obtain first-summer plumage. In most pipit species most of the head and body is moulted (a few feathers, particularly on the scapulars and rump, are often retained) as well as some to all median coverts, a few inner greater coverts (second innermost, 9th, usually replaced first), one to all tertials, and often the central two rectrices.

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Blyth’s Pipit. 2 Jan 2017. © Amar Singh HSS

On 2 January, the bird was in first-winter plumage. The median and greater coverts  seem moderately worn (‘frayed’ edges), and the innermost two greater coverts and upper two tertials have paler edges than the others, probably as a result of bleaching by the sun. There is one unmoulted juvenile outer median covert visible.

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Blyth’s Pipit. 28 Jan 2017.

Taking into account the effects of different light, almost a month later, the plumage looks largely unchanged, though the tertials are looking more worn.

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Blyth’s Pipit. 6 Feb 2017. © Ooi Beng Yean

Ten days later, and we can see the first sign of the pre-breeding moult. The middle tertial is in the process of being shed, and the underparts look different, though it’s hard to say if this is because of new feathers, or old feathers becoming more worn.

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Blyth’s Pipit. 8 Feb 2017. © Ooi Beng Yean.

Two days later, the middle tertial has dropped out. Also we can now see some flank feathers have dropped out (the grey patch below the wing). The greater prominence of peach-coloured feathers on the underparts might also be a result of overlaying feathers having been dropped.

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Blyth’s Pipit. 8 Feb 2017. © Ooi Beng Yean.

A view from the rear on the same day shows that the central tertial on both sides has dropped, and that the longest tertial on the right side is broken. There appear to be two age classes of mantle feathers, with the lower ones having noticeably more gingery fringes. I’m not sure if either of these are fresh feathers or whether this contrast is a result of the previous post-juvenile moult.

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Blyth’s Pipit. 8 Feb 2017. © Ooi Beng Yean.

This spread wing shot shows the difference caused by bleaching. The outer median coverts are protected by the scapulars (and are also newer), so retain buff-coloured fringes, compared to the white fringes of the rest. The same difference can be seen in the outer  and inner greater coverts and the outer and inner primaries. The more exposed feathers have paler (whiter) edges than the ones which are usually covered by other feathers.

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Blyth’s Pipit. 12 Feb 2017. © Lean Yen Long.

Nothing much has changed four days later, but this photo shows the worn state of the back, rump and upper tail coverts.

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Blyth’s Pipit. 18 Feb 2017. © Zhongying Koay

Six days on and some of the median coverts have dropped out. We can just see a new tertial, which has already grown to about half the length of the longest tertial.

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Blyth’s Pipit. 20 Feb 2017.

Two days later, not much change, but we can see that the fringe of the new tertial is a rich gingery colour. We can also see that the outermost tail feather on this side is a new one, not yet full grown.

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Blyth’s Pipit. 20 Feb 2017.

A close-up of the head shows that the head feathers are very worn. Some of the eye-ring feathers have dropped out. One gingery-fringed mantle feather appears to be a new one.

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Blyth’s Pipit.24 Feb 2017 © Mike Kan

Four days on and the new tertial has had quite a growth spurt. Earlier, I had assumed it was a replacement of the middle tertial, but now it looks too long for that. The shortest tertial on this photo is confusing. It seems to have a far broader buff fringe than in the photo two pics up. But close examination reveals that it is in fact the same feather, looking very different in the shade compared to in strong sunlight.

One new inner median covert is now visible. It is gingery-fringed, not white.

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Blyth’s Pipit. 27 Feb 2017.

Just three days later and things are really changing fast. That new tertial is now so long it can only be a new lower tertial. The shorter one we saw on 24 Feb has now all but disintegrated. The innermost greater covert is new, and we can now see at least three new inner median coverts with their broad gingery fringes. The mostly white outermost tail feather is now almost full grown, and we can now see that the central pair are new as well, and almost full grown.

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Blyth’s Pipit. 27 Feb 2017.

Compared with the back-on shot taken on 8 Feb, we can see that nothing has changed in the mantle area, so those brighter lower feathers are probably not freshly moulted. Interestingly, the old longest tertial on the left wing is still present beneath the new one. We can see that moult of the left and right wing is taking place more or less in synchrony.

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Blyth’s Pipit. 6 Mar 2017.

Considering the rapid changes which occurred in the last week of February, things seem to have slowed down a week later.

A new tertial is just emerging next to the innermost greater covert.

The replacement of median coverts is progressing outwards from the innermost, with 4 new ones now visible. The tail feathers known as T5 (i.e. the second outermost pair) are newly growing. These should only have white outer webs and a small wedge of white on the inner web.

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Blyth’s Pipit. 7 Mar 2017. © Zhongying Koay

This fantastic shot just the next day shows us much more detail than we can see on the closed wing. Now we can get a clear look at the lesser coverts. Interestingly, the outermost (buff-tipped) seems to have been replaced, then there’s a gap where old feathers have dropped but new ones have not yet grown out, then another new feather, and the inner three or four are unmoulted old ones. Alström and Mild say that, in post-breeding moult, “the median and lesser coverts are generally moulted rather irregularly”, so perhaps the same applies also when they are moulted in pre-breeding moult.

The four innermost median coverts are new, and the rest are not visible (the old have dropped out and the new have not grown into view yet).

The alula and primary coverts, most of the greater coverts and the primaries and secondaries are unmoulted and still look in remarkably fresh condition (with the exception of the inner secondaries, which are moderately worn).

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Blyth’s Pipit. 7 Feb 2017. © Zhongying Koay

In just 24 hours, the upper tertial seems to have now advanced in length past the innermost greater covert!

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Blyth’s Pipit. 12 Mar 2017. © Chan Kai Soon

Five days later the new tertial has almost reached its full length and the new tail feather is now half grown. There are now 5 new median coverts. The head and body moult seem not to have started.

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Blyth’s Pipit. 2 April 2017. © Zhongying Koay

Into its fourth month on the site, and what a transformation! In the three weeks since it was last photographed, the bird has completed head and body moult. The gingery tone is wearing away from the median coverts, and the bird looks brand new! Unfortunately the morning dew has made the tail bedraggled so we can’t see what’s going on there.

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Blyth’s Pipit. 7 April 2017.

 

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Blyth’s Pipit. 7 April 2017

The second outermost tail feather appears to have much more white on it than the old corresponding feather (see here). I’m not sure if this is age-related.

This is the last date I saw the bird. I don’t know if anyone has seen it since then (nothing on eBird). It is possible that the bird may still be there, as the bulk of overwinterers in India do not leave till late April/early May .

However, the pre-breeding moult seems to have been completed by the first week of April, with all three tertials, the innermost greater covert, all the median coverts, the central and outermost two pairs of tail feathers, and head and body feathers replaced. We can already see the effects of wear on the median coverts, as their fringes are bleaching from ginger to buff. Soon they’ll be white again.

The extended stay of this individual gave many Malaysian birders their first experience of this species, and awakened a new interest in pipits, which will hopefully mean that in future, more Blyth’s will be found. Being able to watch it at such close quarters as it underwent its pre-breeding moult was a rare privilege, and one I will long remember!

My thanks to all the photographers (credited above) for sharing their photos with me and allowing me to use them on this blog.

Notes on a Vagrant Blyth’s Pipit in Malaysia. Part 1 – Behaviour and Ageing

Background

A Blyth’s Pipit was identified at MalimNawar, Perak, on 28th January 2017. Subsequently, it was discovered to have been present from at least 2nd January, when it was photographed by Amar Singh HSS. At the time of writing, the bird is still present (most recently seen on 7th April). This is only the second record of the species for Malaysia.

Throughout its long stay, the bird has been remarkably faithful to one small area of roadside grass, and it has been rather tolerant toward the many photographers and birders who have come to see it. Throughout much of its stay it has been in pre-breeding moult, providing a rare opportunity to document the progress of moult in a single bird.

Behaviour and Habitat

Blyth's-habitat

Blyth’s Pipit habitat. The bird feeds in the longer stalky grass on the far side of the track, as well as in the shorter grass on the near side. © Ooi Beng Yean.

The bird has faithfully frequented a small area of roadside grass verge either side of a dirt track which runs through an area of mining ponds. The track is infrequently used by fish-farm workers and recreational fishermen and birders using motorbikes, cars and SUVs.

The Blyth’s Pipit appears to prefer foraging in grass populated by sparse low vegetation and taller stalks. Its common foraging technique in this habitat is to locate small prey items such as spiders and small bugs by eye and then catch them, often by jumping upwards to pluck them off tall stalks. Paddyfield Pipits and Eastern Yellow Wagtails have also been noted using this foraging method occasionally, but nowhere near as frequently and regularly as the Blyth’s Pipit.

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Blyth’s Pipit foraging. 20 Feb 2017 (left and centre). 24 Feb 2017 (right). © Mike Kan

In shorter grass devoid of taller vegetation it feeds much like other pipits and wagtails. It often forages on or near water buffalo dung, and has been seen to take flies and small maggots from these.

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Blyth’s Pipit with fly sp. 27 Feb 2017.

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Blyth’s Pipit with earwig sp. 8 Feb 2017. © Ooi Beng Yean.

The bird uses the dirt track for dust-bathing (see this short video), and this also seems to represent a territorial boundary for a resident pair of Paddyfield Pipits. At the beginning of the Blyth’s Pipit’s stay, its presence was tolerated by the Paddyfield Pipit pair, but recently, skirmishes have been more frequent.

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Blyth’s Pipit (rear) with a local Paddyfield Pipit. 20 Feb 2017.

The Blyth’s Pipit rarely calls unless in an altercation with a Paddyfield Pipit. Normally when flushed by people or dogs it flies off silently, flying a short distance, and then circling back to its preferred area shortly after the perceived threat has passed. When flushed it occasionally perches on telegraph wires or a fence post. It does not habitually bob the tail up and down like a wagtail, but occasionally flicks the tail downward rather deliberately.

What age?

Determining the age of pipits can be difficult! It all depends on the fine details of plumage and moult, particularly in the wings and tail.

There is a detailed summary of moult in pipits and wagtails in Alström and Mild’s Pipits and Wagtails of Europe, Asia and North America, which is available online as a pdf here (scroll down to page 24ff). It bears reading in full, but I will attempt a précis of the salient points here.

Juvenile plumage: The first proper plumage succeeding natal down. The feathers develop simultaneously so are uniformly fresh or worn.

Post juvenile moult: Begins 2-5 months after fledging. In all pipits except some Paddyfield Pipits, this is a partial moult. It includes the head and body feathers and a variable number of secondary coverts and tertials, sometimes also the central pair of tail feathers. Most lesser coverts, none to all median coverts, none to a few inner greater coverts and none to all tertials are renewed during the post-juvenile moult. Once post-juvenile moult is complete, the bird is in first winter plumage.

Pre-breeding moult: In the late winter or early spring of the second calendar year, i.e. when the bird is 9–10 months old, most pipits and wagtails go through a partial pre-breeding moult to obtain first-summer plumage. In most pipit species most of the head and body is moulted (a few feathers, particularly on the scapulars and rump, are often retained) as well as some to all median coverts, a few inner greater coverts (second innermost, 9th, usually replaced first), one to all tertials, and often the central two rectrices.

Post-breeding moult: At the age of a little over a year, after breeding, the first-summer  bird goes through a complete post-breeding moult, resulting in adult plumage, i.e. the final plumage.

The moults in adults follow the schedule and type of the young bird after the post-juvenile moult, i.e. a partial pre-breeding moult in late winter to early spring and a complete post-breeding moult which starts shortly after breeding. (The way I remember this is “Some in Spring; All in Autumn!”). The post-breeding moult usually commences either with the innermost primary or with some feathers on the head and body, often mantle feathers. The primaries are moulted descendantly (from the innermost outward), and the primary coverts are usually moulted in phase with their corresponding primaries. Soon after the moult of primaries has begun, that of rectrices and tertials begins. The tail moult commences with the central pair and normally continues centrifugally. The central tertial is usually shed first, approximately at the same time as the third primary, then usually the shortest and finally the longest. The secondary moult usually begins at about the same time as the sixth primary is shed, and proceeds ascendantly, starting with the innermost. However, the greater coverts tend to moult from the body outwards—thus not renewing in phase with their corresponding secondaries—but the sequence is often irregular, and sometimes most of them are renewed at much the same time. The median and lesser coverts are generally moulted rather irregularly, and most or all of the medians are often renewed simultaneously. The alula is generally replaced after the secondary coverts, usually in an irregular sequence. The outermost primary and innermost secondary get fully grown at approximately the same time, the latter often marginally later. The primaries, primary coverts and secondaries (but not necessarily the secondary coverts, tertials and alula) are as a rule moulted symmetrically across the wings. The head and body moult is usually completed around the same time as, or slightly before, the moult of the flight feathers, the head on average slightly later than the body.

The moult usually lasts 1–2 months, and is completed before the autumn migration.

Ageing

Most first-winter pipits show two generations of secondary coverts, often also tertials. Retained juvenile secondary coverts and tertials are more worn and, owing to bleaching, show paler tips/edges and marginally paler centres than newly moulted ones. Unmoulted juvenile secondary coverts are also usually slightly shorter than adjacent newly moulted ones. In several species (particularly the ‘large’ pipits) unmoulted juvenile secondary coverts and tertials are also differently patterned compared to newly moulted adult-type feathers. The resulting moult contrast (moult limit) is diagnostic for first-winter birds, as adults in the autumn show only one generation of secondary coverts and tertials (but see below).

It should, however, be noted that wear and bleaching is not uniform across the wing feathers, and this may result in the appearance of moult contrast. The inner primaries and outer secondaries are less exposed than the outer primaries and inner secondaries, and therefore less subject to wear and bleaching. The inner greater coverts, notably the 9th (second innermost) although not the usually concealed 10th, are more prone to wear and bleaching than the outer ones, and hence the outer greater coverts sometimes appear to be newer than the inners. The outermost three or so median coverts are less subject to bleaching and wear than the rest, and frequently look fresher than adjacent median coverts even when the same age. The tertials may become more worn than the secondary coverts.

It might be useful to do a quick review of the topography of the wing, courtesy of Beng Yean’s perfectly-timed photo below.

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Blyth’s Pipit. 6 Feb 2017. © Ooi Beng Yean.

  1. Marginal (secondary) coverts (sometimes lumped together with the lessers)
  2. Lesser (secondary) coverts
  3. Median (secondary) coverts
  4. Greater (secondary) coverts
  5. Alula
  6. Primary coverts
  7. Primaries
  8. Secondaries
  9. Tertials

The most important group of feathers in determining the age of this bird are the median coverts, as juvenile feathers are differently patterned from first winter and adult feathers (in Blyth’s Pipit).  In juveniles, the black centres of the median coverts follow the shape of the feather, whereas on first winters and older, they are more square-cut, as these are. See here for a juvenile. Juvenile-patterned median coverts can apparently be retained until ‘midwinter’ (see these pics taken on 30 December).

But is the bird in its first winter or is it older?

If this bird is a first winter, one would expect to see 1. Evenly aged remiges (primaries and secondaries) and 2. Possibly (though not always) some evidence of moult contrast due to their being two ages of e.g. coverts. 3. Possibly (though not always) the central pair of rectrices (tail feathers) being newer than the rest.

If it is an adult, one would expect to see 1. No moult contrast, though possibly some unevenness of bleaching, with the outer greater coverts and the outer median coverts being less bleached than the rest of the feathers in their respective feather tracts. 2. Perhaps some unevenness of wear in the remiges (with inner secondaries and inner primaries being more worn than the rest, because they were moulted earlier in the complete post-breeding moult). 3. The tail feathers being evenly aged.

In the photo above, we can see:

1 The primaries and secondaries appear uniformly aged.

2. No obvious moult contrast in the coverts.

So, honestly, I cannot age the bird from this photo!

Fortunately, the first photos taken of this bird were on 2 Jan – much earlier than this photo. Here’s one:

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Blyth’s Pipit. 2 Jan 2017. © Amar Singh HSS.

A close look at the median coverts reveals something interesting!

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Blyth’s Pipit. 2 Jan 2017. © Amar Singh HSS

The question is – is this differently-patterned feather a median covert or a lesser covert? Comparing it with the lesser coverts on the numbered photo, it seems more worn and to have a narrower pale fringe than those feathers, so I think it’s a median covert. Here’s another view:

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Blyth’s Pipit. 2 Jan 2017. © Amar Singh HSS

I think the feather labelled 1. is a median covert, and the other labelled 2. is a lesser covert (with a buffier, broader fringe).

If I’m correct, and it is a median covert, then it is a juvenile covert, which ages this bird as a first winter (hatched in 2016). By the time Beng Yean’s photo was taken on 6 Feb, this feather had dropped out and been replaced by an adult-patterned covert.

I might be wrong – in which case, please let me know what you think. I did say that ageing pipits can be difficult!

In the next post, I will look in more detail at the progress of the pre-breeding moult in this bird.

My thanks to Amar Singh HSS, Mike Kan and Ooi Beng Yean for allowing me to reproduce their photos in this post.

Identification of Paddyfield, Richard’s and Blyth’s Pipits in Malaysia

There are six pipits (Anthus spp.) on the Malaysian list. Of these, only Paddyfield Pipit is resident. The others are either more or less regular but localised non-breeding visitors (Olive-backed Pipit and Red-throated Pipit), scarce migrants (Pechora Pipit – Bornean Malaysia only – and Richard’s Pipit) or vagrants (Blyth’s Pipit – Peninsular Malaysia only).

The pipits can be fairly reliably grouped according to their preferred habitat in Malaysia: Paddyfield, Richard’s, Blyth’s and Red-throated are lowland open country birds; Olive-backed occurs mostly at montane and submontane altitudes and in more forested habitats; and Pechora has a predominantly coastal distribution in northern Borneo, preferring coastal scrub.

red-throated-pipit

Red-throated Pipits usually show at least some pinkish colouration on the throat. Even when they lack this, they differ from the larger pipits by the heavier streaking on the underparts which extends all the way down the flanks, and by the more heavily streaked upperparts.

In this article, I will focus on differentiating the three ‘larger’ species – Paddyfield, Richard’s and Blyth’s (in fact, size differences are small, and there is overlap in length with the so-called ‘smaller pipit’species, but ‘larger pipits’ differ in having proportionally longer legs and a stockier structure).

STATUS

Paddyfield Pipit is the default pipit species in Malaysia, being extremely common in a range of open country habitats.

Richard’s Pipit is at best a scarce non-breeding visitor. Because the resident Paddyfield Pipit was formerly lumped with Richard’s Pipit, the historical status of the species is unclear. In Peninsular Malaysia, the first acceptable record was at Chuping, Perlis, as recently as 2013. Since then, it has been recorded annually at the site between Nov and Feb, but nowhere else in the Peninsula. On Borneo, it is probably a scarce migrant, but well-documented records are few and far between.

Blyth’s Pipit  has been recorded just twice; once at Chuping, Perlis, in Jan 2010, and once at Malim Nawar, in Jan/Feb 2017.

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Malaysia’s first Blyth’s Pipit, recorded at Chuping, Perlis, on 7 Jan 2010.

HABITAT PREFERENCE

Paddyfield Pipits frequent open grass fields, roadside verges and sandy tracks, and cleared ground with little or no vegetation.

Richard’s Pipits at Chuping prefer much longer grass and more overgrown fallow fields than Paddyfield Pipits. They are rarely flushed from the roadsides there, and are very difficult to see on the ground because of the thicker ground cover they frequent.

Both Blyth’s Pipits  were originally observed on sandy tracks, and subsequently fed on short grassy verges, frequently associating with Paddyfield Pipits, and apparently sharing their preferred habitat.

CALLS

It may seem strange to talk about what the larger pipits sound like before what they look like, but, more often than not, it is the call which gives the first clue that we are dealing with something other than a Paddyfield Pipit.

Pipits are generally rather vocal, particularly when  flushed or in flight. It is also true that the larger pipits use more than one type of vocalisation, so it is well worth paying attention to the full range of calls made.

As is so often the case, the key to finding a rare species is to make every effort to become familiar with the common ones. Recording and noting down the various calls uttered by Paddyfield Pipits is essential foundational work for anyone with an interest in locating Richard’s or Blyth’s Pipits. Xeno-Canto Asia has an excellent library of bird sounds where you can gen up on the vocalisations of all three species.

Paddyfield Pipits utter a variety of short, sharp calls, many of which sound like “chup” orchip” to my ears (listen to this and this).

Richard’s Pipits commonly utter an explosive “schreep“(listen here), which is very different from any Paddyfield Pipit call (be careful not to confuse it with the softer, thinner “tseep” of Eastern Yellow Wagtail). I’ve quite often seen Richard’s Pipits near dusk at Chuping as they’ve flown overhead going to roost, calling loudly.

Both Malaysian Blyth’s Pipits  were initially located by call. Neither time did I recognise the call as Blyth’s, but both times I knew it was something different and worth investigating. It sounds more buzzy and ‘jangly’ than Paddyfield or Richard’s. Listen here. However, some of the calls sound more Paddyfield-like (such as this one), so don’t be too quick to discount a funny pipit which sounds like a Paddyfield!

PLUMAGE AND STRUCTURE

Paddyfield Pipit

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Paddyfield Pipit in alert posture. Paddyfield Pipits typically look 1) short-tailed 2)show dark lores and 3) richly-coloured ear coverts which are obviously darker than the area surrounding them, creating the impression of a cheek patch. 4) The upper parts and crown are not distinctly streaked.5) The head seems proportionally rather large and wedge-shaped, with a flattish crown.

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Colour tones may vary according to the light, background colour, and extent of feather wear. Nevertheless, the features mentioned above usually hold true. Some birds show light streaking on the rear flanks (centre photo), while others have unstreaked rear flanks. 6) The bill appears long and relatively thin. 7) The median coverts usually show  broad buff edges and dark brown centres when fresh. When worn, they are medium brown with slightly paler edges.

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Typically, Paddyfield Pipits show 8) quite heavy breast streaks, and 9) there is usually some contrast between the buffier background colour of the breast and flanks, and the paler lower breast and belly. 

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Usually the belly is whitish, but some birds show more uniform buff below, more like Blyth’s Pipit.

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Once in a while, variations show up. This bird had pale lores and looked paler overall. However, the bill and head look right for Paddyfield Pipit.

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This fresh-plumaged bird appeared much buffier overall than typical Paddyfield Pipits. It appears quite strong-billed, has strongly-patterned median and greater coverts and a dark lateral crown stripe. Some of these features fit Richard’s Pipit. Nevertheless, the overall structure (short-looking tail, not especially long legs) and head pattern (dark lores and ear coverts) seem to fit Paddyfield Pipit best. 

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Another pale-lored Paddyfield Pipit. 

Some of these trickier individuals show that identification is not always straightforward, based purely on plumage features. It is always worth taking time to make a thorough appraisal of atypical birds, getting as many photos as possible, and recording the call if this is possible.

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Juvenile Paddyfield Pipits are more distinctly-marked than adults, but their markings do not closely resemble any other species. Besides, there’s usually an adult or two around!

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In flight, Paddyfield Pipits look short-tailed. They usually call frequently when in flight. Some books mention that Richard’s Pipits characteristically dangle their feet in flight, and hover before landing. As these habits are commonly observed in Paddyfield Pipits, I don’t think they are of any value for identification.

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paddyfield-labelled

Richard’s Pipit

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Richard’s Pipits are 1) larger than the other two species, sometimes markedly so. Structurally, they are 2) the longest-tailed and -legged of the three. 3) The overall colour is warmer and buffier than is typical of Paddyfield Pipits.

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4) The bill is strong with an evenly-curved culmen. 5) The lores are typically pale, as are the lower ear coverts, which result in a more ‘open’ facial expression than Paddyfield. Their preference for long grass can make them difficult to observe on the ground.

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6) The crown is rounder (the head is less wedge-shaped) than Paddyfield, and 7) is typically more distinctly-streaked.8) The breast-streaking is less dense than on most Paddyfield Pipits.

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9)The long tail seems rather loosely attached to the body  when the bird is walking

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The plain-faced appearance, caused by pale lores and lower ear coverts, is striking on this bird. This individual has moulted out its median coverts. The rear flanks are lightly streaked.

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In flight, they look a much stockier, bigger bird than Paddyfield Pipit, and the difference in tail length is obvious. The heavy bill and extremely long hind-claw are also evident in these pictures.

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Blyth’s Pipit 

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From a distance, 1) the pale buff plumage, 2) well streaked  mantle and crown, and 3) blackish-centred, whitish-tipped median coverts stand out. 4) The bill looks short and 5)  the head seems small and rounded.

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6) The pale lores coupled with 7) the relatively weak face pattern (pointed supercilium, pale ear coverts and indistinct moustachial stripe) create an ‘open-faced’ expression.

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8) Structurally, Blyth’s Pipit looks slender and well-proportioned. The tail is longer than Paddyfield, but shorter than Richard’s.

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At certain angles, there is a greyish triangular smudge on the lores.

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9) The breast streaking is lighter than on typical Paddyfield, and 10) there is little or no contrast  between the colour of the breast and belly. Photo credit: Ooi Beng Yean

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11) The crown is finely and distinctly streaked

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At times, the ear coverts look slightly darker than the surrounding area, but are not nearly so dark and contrasting as on Paddyfield Pipit. The flanks have a distinctly peach-coloured wash and are unstreaked. Photo credit: Ooi Beng Yean

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The pattern of the median coverts is distinctive. The central dark area is diamond-shaped, rather than triangular (as on Paddyfield and Richard’s), and the whitish edges are very clearly demarcated from the dark centres (on Paddyfield and Richard’s they blend into each other more smoothly, especially on the edges). Photo credit: Ooi Beng Yean

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When feeding, Blyth’s Pipit adopts a horizontal, wagtail-like stance, but stands erect when alert.

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Conclusion

There’s lots more to learn about plumage variation in the larger pipits, so this is certainly not the last word on the matter, particularly as for the latter two species, my observations are limited to a small number of individuals.

Nevertheless, I hope this article will encourage you to take a closer look at pipits next time you have the opportunity to observe them, and that it will give you some idea of what you should be looking and listening out for.

A final plea – when you do positively identify pipits (or any other birds for that matter) – please do submit your observations to eBird Malaysia; doing so regularly will be of immense benefit in adding to our understanding of the true status of Malaysia’s beautiful birds.

larger-pipits

Chinese Egrets in Malaysia – Where, when and how to find them

[This article was first published on the eBird Malaysia website].

White egrets are notoriously confusing for the novice and experienced birder alike, with their lack of obvious plumage features and variable ‘bare part’ (legs, bill and lores) colouration. Identifying them correctly largely depends on an appreciation of subtle differences in structure and shape, as well as a knowledge of their habitat preferences.

This article focuses on identifying Chinese Egret (Egretta eulophotes), a globally Vulnerable species with an estimated world population of fewer than 10,000 (BirdLife International 2017), and in particular, differentiating it from the main confusion species – Little Egret (Egretta garzetta) and white morph Pacific Reef-Heron (Egretta sacra).

Where and when to look for Chinese Egrets

The bar chart for the species on eBird shows that it is most frequently observed between September and early May, with just a very few ‘oversummering’ records. Little Egret and Pacific Reef-Heron, on the other hand, can be seen all year round.

In Peninsular Malaysia, small numbers are seen at a few localities along the west coast, such as the Klang Islands (Selangor), Parit Jawa (Johor) and the Teluk Air Tawar-Kuala Muda coast IBA (Pulau Pinang). Numbers are much larger in Bornean Malaysia, with Bako-Buntal Bay IBA (Sarawak) recording counts of almost 100 birds. A survey of the entire Sarawak coastline in 2010-2012 recorded a total of 637 Chinese Egrets (Bakewell, D. et al. 2017). In Sabah, Chinese Egrets can be regularly seen along the coast west and east of Kota Kinabalu, and around Sandakan Bay. A species map for Chinese Egret on eBird shows the distribution of records in Malaysia.

Chinese Egrets are largely restricted to intertidal areas on the coast, though they may gather to roost and occasionally feed in coastal aquaculture ponds in Sarawak. They do not habitually frequent rice paddies or freshwater habitats.

Little Egrets are equally at home in saltwater and freshwater habitats, and frequently occur in loose flocks of 100 and more in Malaysia. They also breed colonially locally.

Pacific Reef-Herons tend to occur alone or in pairs (often a dark morph bird is paired with a white morph individual). They prefer rocky and sandy shorelines rather than intertidal mud, and offshore islets and rocky outcrops. They do not occur in freshwater habitats.

How to find a Chinese Egret

The first step is to go to a place where they are likely to be found and at the right time of year (see above). Once you’ve done that, the key is learning how to tell them apart from the main confusion species, Little Egret and white morph Pacific Reef-Heron.

In breeding plumage (from late April), Chinese Egrets are relatively straightforward to identify, as they are the only egret to show a combination of yellow bill and black legs with yellow feet. They also have distinctive fan-shaped head-plumes, which are unlike the twin filament plumes of Little (Pacific Reef-Heron also has two short filament-like head-plumes).

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Chinese Egret coming into breeding plumage, Sg Seria, Brunei, 28 April 2010

 

In non-breeding plumage, identification is more tricky.

Key things to focus on are:

  • Bill shape and colour, loral skin and head-plumes
  • Leg length and colour
  • Overall structure
  1. Bill shape and colour, loral skin and head-plumes

KONICA MINOLTA DIGITAL CAMERAChinese Egret’s bill is dagger-shaped. The lower mandible is yellow for more than half its length, and the base of the cutting edge of the upper mandible is yellow.

The upper line of the loral skin (the skin between the eye and the bill base) kinks downward in front of the eye. This creates a distinctive expression even at a distance. The loral skin is grey-blue, becoming brighter blue in breeding plumage.

What’s left of the head-plumes are ragged and shaggy.

little-egret-headLittle Egret’s bill is thinner and more parallel-sided, more pencil-shaped. The base of the lower mandible is frequently pale (this is seldom illustrated in books), but is pinkish or whitish, not strongly yellow. The upper mandible is all dark (this bird’s is covered in mud, so looks pale).

The upper line of the loral skin is more or less straight, creating a ‘bland’ expression.

Vestigial head-plumes are filamentous – one or two long, thin feathers.

pacific-reef-heron-headPacific Reef-Heron’s bill is heavier than and not as sharp as Chinese or Little. It is variable in colour, and can show the same rich yellow as Chinese. However, the yellow tends to be more ‘smudgy’ and less clearcut than on Chinese, and often the bill tip is yellow, which is not the case with non-breeding Chinese.

The loral line is more or less straight and the skin appears to go over the bill base.

The vestigial head plumes are typically two short filaments.

2. Leg length and colour

chinese-egret_legs_150110_img_0221Chinese Egrets have mostly greenish-yellow legs in non-breeding plumage; they begin to become black in the early months of the northern spring.

little-egret-nhkLittle Egrets usually have black legs and yellow toes, but juveniles can show greenish or yellowish legs (the left hand bird in this picture), which are a potential trap for the unwary. Photo credit: Neoh Hor Kee.

pacific-reef-egret-legs_191008_img_8777_edited-1Pacific Reef-Herons’ legs are variable in colour. They are noticeably shorter than those of Chinese Egrets, especially the tibia. The legs also appear thicker than Chinese, especially the tibio-tarsal joint.

 3. Overall structure

pacific-reef-heron-structurechinese-egret_structure_150110_dscn8082Pacific Reef-Heron (top photo) looks shorter-necked and legged and generally stockier than Chinese and Little. Chinese Egrets (bottom photo) are skinny-looking, more like Little Egret in overall proportions.

 A Final Word

As with other species which are difficult to identify, the key to solving this puzzle is to base identification on as many features as possible, not just on one. These include habitat, time of year, numbers present and a combination of structural and bare part details. Photos are always helpful, especially in judging subjective details like leg length, and finer points like the shape of the loral skin.

Happy hunting!

 References:

BirdLife International (2017) Species factsheet: Egretta eulophotes. Downloaded from http://www.birdlife.org on 20/01/2017.

Bakewell, D., Wong, A., Kong, D. & Au, R. 2017. Waterbird Surveys of the Sarawak Coast (2010-2012). [A Report by the Malaysian Nature Society-Bird Conservation Council (MNS-BCC) Waterbirds Group in partnership with the Sarawak Forestry Corporation]. Kuala Lumpur:

Chestnut-necklaced Partridge – one species or two?

One of the many highlights of 2015 for me was the opportunity to observe Chestnut-necklaced Partridges in Sabah and Peninsular Malaysia within a few weeks of each other.

The Clements and IOC checklists treat these two forms as subspecies – Arborophila charltonii charltonii (range: S Thailand to S Myanmar and Malay Peninsula) and A.c. graydoni (range: N Borneo (Sabah)). A third subspecies is A.c. atjenensis (range: N Sumatra (Aceh province)). However, Birdlife International and HBW split charltonii and atjenensis from graydoni as Chestnut-necklaced Partridge and Sabah Partridge respectively.

HBW describes the ways in which graydoni differs from charltonii  as follows:

“Formerly treated as a subspecies of A. charltonii, but differs in its plain dirty white vs plain tawny-buff ear-coverts (2); absence of a distinct black upper necklace from the lower throat around below the ear-coverts (2); much darker, richer chestnut on upper breast with black vs greyish-brown lower breast feathers, more narrowly, evenly and distinctly barred with buff (3); belly with darker rufous and rufous-chestnut coloration (ns[1]); and darker upperparts (ns[1]).”

Whereas Sabah Partridge has a Red List threat classification of Least Concern (LC), Chestnut-necklaced is considered Vulnerable (VU).

I had the chance to watch and photograph a single graydoni from a boat on the Kinabatangan River, as it strutted and called along the bank of the river just feet away, for over an hour.

Sabah-Partridge_IMG_5129

Aborophila (charltonii) graydoni. Compare this with the points outlined in the HBW description above.

Not long afterwards, I had a memorable encounter with charltonii in Peninsular Malaysia, while sitting in a hide. The bird spent over two and half hours in front of me, down to about 5 feet away, seemingly oblivious to my presence!

Chestnut-necklaced-Partridge_IMG_7490

Charltonii. Both these images are uncropped.

Here are a couple of short videos of the bird calling.


<p><a href=”https://vimeo.com/150893762″>MVI_7245 Chestnut-necklaced Partridge</a> from <a href=”https://vimeo.com/user23184508″>Dave B</a> on <a href=”https://vimeo.com”>Vimeo</a&gt;.</p>


<p><a href=”https://vimeo.com/150896550″>MVI_7358</a&gt; from <a href=”https://vimeo.com/user23184508″>Dave B</a> on <a href=”https://vimeo.com”>Vimeo</a&gt;.</p>

These are best viewed fullscreen and with the resolution pumped up to 720p (click on the HD symbol at the bottom right of the screen)

Having so recently seen the Sabah version, I was pretty surprised to see how different the Peninsula form looked. I made a few composite montages to make comparison easier. The Sabah version is always on the left in the pictures below. In making the following observations I realise that I am drawing on a sample size of one in each case, too small to make generalisations. Nevertheless, differences are suggestive.

Graysoni-and-charltonii2

The most obvious difference at first sight, apart from the ear covert patch, is the difference in the colour of the bill base and eyering – nondescript dark brownish-grey in the Sabah example and vibrant reddish-pink in the Peninsula bird. Wells mentions some variation in this feature on charltonii:

“Periorbital skin reddish-orange; bill black in four specimens, black with a reddish base and yellow-green tip to lower mandible in one, all olive-green in one, all brown in one and all yellow-brown in one – variation that is not yet understood.”

The throat feathering on charltonii seems to have much less black on the feather tips compared to graydoni.

Graysoni-and-charltonii1

When seen in detail, the head patterns are fairly different from each other. The Sabah example differs in having:

  • a darker, grey-brown crown
  • whiter, less-streaked supercilium
  • a white loral spot
  • the whitish-grey ear coverts bissected by a dark vertical line
  • more evenly dark-tipped throat feathers, lacking a distinct lower necklace

Other differences are:

  • darker, greyer-brown breastband with thinner, paler transverse barring
  • Belly and flanks dark, rich chestnut, being similar to the colour of the lower neck (much paler peach on the Peninsula bird)

Graysoni-and-charltonii3

Although the Sabah bird is in shade and the Peninsula one in bright sunlight, the upper parts of the Sabah example do seem to be darker, greyer, and more thinly barred.

Structurally, the Sabah bird seems longer-bodied, longer-necked and larger-headed.

Graysoni-and-charltonii4The flanks are distinctly different – plain on the Sabah form and heavily barred on the Peninsula bird.

Graysoni-and-charltonii5The profile view seems to add weight to the structural differences suggested above. The Sabah bird looks longer and ‘rangier’ compared to the dumpy and rotund Peninsula one.

Graysoni-and-charltonii6

Lastly, a close-up of the head in profile shows that the bills are not only different in colouration but also in shape, with the Sabah bird having a longer, more tapered bill compared to the thick, almost bulbous bill of the Peninsula individual.

The Peninsula bird was only ever heard to make the single-noted repetitive crooning trill which can be heard in the videos, and never the rising and falling see-saw shriek which Sabah birds make when in full cry. However, that may be explained by the fact that the bird was alone, rather than part of a pair. The louder calls are more usually heard from antiphonally duetting pairs of graydoni.

Whether or not the two forms represent two full species or not, it was certainly a privilege to be able to observe both at such close range within such a short time. I’ll finish with a few more shots of the bird on the Peninsula, which came too close to focus on at times.

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Chestnut-necklaced-Partridge_IMG_7431

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