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NEW Acrocephalus puzzle in Leyte (Philippines) (1 Viewer)

Valéry Schollaert

Respect animals, don't eat or wear their body or s
For those interested, I had a problem with large reed warblers recently discussed here.

The same species are probably involved but not the same individuals. Unfortunately, the "magic" place where I had seen several reed-warblers was cut to make rice plantation. Bitterns, painted-snipes and rails are still there, joined with Barred Buttonquail, but no reed warblers anymore.

Well, near my house there is a little stand of very high reeds where I hear Clamorous Reed-Warbler (Acrocephalus stentoreus harterti, sometimes grouped with Australasian Reed Warbler, split from Clamorous) every morning; I'm now very familiar with its song.

I can't usually take photos because we just have the sun in the face at this time. However, I tried this morning while the sun was still very low (hence noisy photos).

Haterti was singing as usual, and I believed to see it on top of reeds, and got the first photo here attached. A minute later, I saw a reed warbler closer to me and shoot, without taking more attention (thinking it was the same bird); that's the second photo.

It is only now, sorting the photos, I realized it is NOT AT ALL the same bird!

The second bird has a beak at least twice bigger, and much longer pp, and different colour although I wouldn't rely on that with the terrible light conditions.

So is my first bird harteri? Can it has such a tiny bill????

Is second bird a typical Oriental Reed Warbler or I missed something???

!! THANKS !!
 

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As I see I'm not alone to find it difficult, I spent 3 hours yesterday in a little banana plantation with much undergrowth where harterti has a territory. I heard them singing, calling (so different from Oriental Reed-Warbler) and... finally... got decent shots! I've got more than 40 pix of this quality, what a relief! :)

Hope this photo can help a bit.
 

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The second pic in post #1 and bird in #2 are Oriental Reed alright. But the first bird looks different somehow like a smaller Acro. Bill very slender and also shape of head not right for one of the large species. From what can be seen it does look too plain for Streaked Reed Warbler but the other Acro on the Philippinian list is Black-browed Reed which is a rarity (or overlooked?). Wouldn't ID it as Black-browed Reed from this pic but maybe worth to try to search for it again...
 
The second pic in post #1 and bird in #2 are Oriental Reed alright. But the first bird looks different somehow like a smaller Acro. Bill very slender and also shape of head not right for one of the large species. From what can be seen it does look too plain for Streaked Reed Warbler but the other Acro on the Philippinian list is Black-browed Reed which is a rarity (or overlooked?). Wouldn't ID it as Black-browed Reed from this pic but maybe worth to try to search for it again...

Thanks, yes it looks like a small Acro.

In second post, however, it is definitely a breeding local harterti, this was for comparison. Song, call and breeding locally all excluded Oriental R.W.
 
This is another photo of the small Acro. You can see the short pp and plain mantle. Is there any other option that Black-browed suggested by Carery or can we reasonably think it is the one?

Very exciting! The place is at 30m from home, I will try my best to get better shots.
 

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It's not a Black-browed, which would have a broader supercilium extending well behind the eye, which should be visible on these photos. I'd also expect the black brow to be visible here. The structure also doesn't look quite right IMO, plus BbRW is usually a really skulking species in winter - not like these photos.

I actually think this is a large Acro despite the first photo seeming a bit misleading. I think this may be due to a slight degree of foreshortening from the head being angled away from the camera. It doesn't look right for Oriental and I think it may be Clamorous, but don't have a lot of experience of that.
 
It's not a Black-browed, which would have a broader supercilium extending well behind the eye, which should be visible on these photos. I'd also expect the black brow to be visible here. The structure also doesn't look quite right IMO, plus BbRW is usually a really skulking species in winter - not like these photos.

I actually think this is a large Acro despite the first photo seeming a bit misleading. I think this may be due to a slight degree of foreshortening from the head being angled away from the camera. It doesn't look right for Oriental and I think it may be Clamorous, but don't have a lot of experience of that.

Agree with John...the very short pp points to harterti IMO.

Grahame
 
I found it impossible to see some features other than structur on the first photo. On the second photo, however, it is clearly not BbRW. I would also say here it looks like Clamorous/Australasian RW.

Valéry, I'm a little confused about your ID of the larger Acros - also in the previous thread you linked in post #1. Did I get you right, you take the birds in this thread as CRW and those very short-wing bird in the other thread as ORW? According to all sources I checked it should be the other way round. Moreover, you talk about vocalisation. It would be very helpful to upload some recording you made yourself from the birds in question. This can easily be done via smartphone or your camera in video mode. You would just need to be as close as possible on a windless...
 
I found it impossible to see some features other than structur on the first photo. On the second photo, however, it is clearly not BbRW. I would also say here it looks like Clamorous/Australasian RW.

Valéry, I'm a little confused about your ID of the larger Acros - also in the previous thread you linked in post #1. Did I get you right, you take the birds in this thread as CRW and those very short-wing bird in the other thread as ORW? According to all sources I checked it should be the other way round. Moreover, you talk about vocalisation. It would be very helpful to upload some recording you made yourself from the birds in question. This can easily be done via smartphone or your camera in video mode. You would just need to be as close as possible on a windless...

Actually, there is just a problem with the way you see the pp on the first bird of my first threat. Harterti shows a much shorter pp than Oriental, as shown on the photos I published here. It seems to be more obvious than I expected.

As you confirmed, bird on my first post here is Oriental R. W., so no I don't ""take the birds in this thread as CRW"


As Harterti is not that well known and few confirmed images taken in the field are available. It is important to know what we compare with. So I gave you a photo here (second post) of a 100% confirmed Harterti showing all needed details.

You can see also the shorter pp compared to the first bird of my first threat, now confirmed Oriental, so no "those very short-wing bird in the other thread as ORW", the ORW is the longer wing bird on the first post, then later on I posted a photo of harterti taken in the same place.
 
Thank you very much for your answer! I think now I get you...

Meanwhile, what really puzzles me is the second bird you photographed (post #1, pic 1). It looks so different from all the other, much larger billed Acros in both threads. It seems warmer brown coloured, size and shape of bill obviously different, longer tailed...

I was basing my IDs mainly on the lenght of the primary projection. Just now it struck me that I completely forgot about moult (which I suppose would take place about now in Great Reed Warbler). What if ALL the large billed birds are infact ORWs but with oddly short wings due to missing feathers? Could moult affect the pp that much? This would explain why now, about a month later, they are much more straightforward to ID. Only I would have expected that the fringes would look somewhat fresher, hmmm.

At the moment I actually consider that the only CRW harterti you have posted so far might be the bird shown in post #1 (pic1) and post #5. What do you think? Others?
 
Thank you very much for your answer! I think now I get you...

Meanwhile, what really puzzles me is the second bird you photographed (post #1, pic 1). It looks so different from all the other, much larger billed Acros in both threads. It seems warmer brown coloured, size and shape of bill obviously different, longer tailed...

I was basing my IDs mainly on the lenght of the primary projection. Just now it struck me that I completely forgot about moult (which I suppose would take place about now in Great Reed Warbler). What if ALL the large billed birds are infact ORWs but with oddly short wings due to missing feathers? Could moult affect the pp that much? This would explain why now, about a month later, they are much more straightforward to ID. Only I would have expected that the fringes would look somewhat fresher, hmmm.

At the moment I actually consider that the only CRW harterti you have posted so far might be the bird shown in post #1 (pic1) and post #5. What do you think? Others?

Well, there are many birds I added on Leyte list already compared to Kennedy book and HBW, but still literature can help. The local specialist, Desmond Allen, too, although he didn't comment the very last photos yet.

According to books, only harterti is recorded on Leyte, and my photo or ORW is a new bird for the island. This is also why I submitted it (first thread), I wanted to double check.

According to Desmond who is very familiar with both, they are extremely similar, even not identifiable, visually. Well, I know reed warblers are terrible, but we have, fortunately, the sound. If this is true, the smallish one suggesting Black-browed wouldn't be harteri though...

Also according to Desmond, ORW warbler usually don't sing in the Philippines, and there is no breeding record.

Well, I heard the first bird of first threat singing (the only ORW I heard singing on Leyte) once, and it was much Great Reed Warbler like (former sub-species); the call is strong and clear-cut. But I was new here, and both were still little known for me.

Since then, I became familiar with the very different song of harterti, a very common but elusive bird. Somehow, it is more like Striated Grassbird than ORW. The call is much softer and not at all similar to ORW.

Well, still trying to find the best visual features. As the books and internet don't really illustrate harterti properly, I found a territory with a breeding couple of that taxon and made the photo I shared on post 2, as well as plenty more. I costed me a lot of time, but it was worth it.

The male defends the territory daily with harterti song, both have the softer call compared to ORW, and ORW doesn't breed in the country. My photo was added as harterti in the catalogue of Wild Bird Photographers of the Philippines. That you can challenge that identification alone based on one picture seems surprising, although it is always interesting to defend a conclusion, it is how we learn to have better arguments. So please keep on.


I'm now totally sure of 2 birds on this thread, the ORW in post 1 and of course harterti in post 2, but not yet convinced by the smaller bird. Hope to see it again of have more comments...
 
Thank you very much for your answer! I think now I get you...

Meanwhile, what really puzzles me is the second bird you photographed (post #1, pic 1). It looks so different from all the other, much larger billed Acros in both threads. It seems warmer brown coloured, size and shape of bill obviously different, longer tailed...

I was basing my IDs mainly on the lenght of the primary projection. Just now it struck me that I completely forgot about moult (which I suppose would take place about now in Great Reed Warbler). What if ALL the large billed birds are infact ORWs but with oddly short wings due to missing feathers? Could moult affect the pp that much? This would explain why now, about a month later, they are much more straightforward to ID. Only I would have expected that the fringes would look somewhat fresher, hmmm.

At the moment I actually consider that the only CRW harterti you have posted so far might be the bird shown in post #1 (pic1) and post #5. What do you think? Others?

Roland/Valery

Regarding moult of ORW this extract from Kennerley et al (2010)..
'Unusually amongst Palearctic Acrocephalus, adults and young birds have a complete moult on the breeding grounds that is complete prior to autumn migration. In adults , this commences in mid July and is usually finished by early to mid September. Young birds begin their complete post-juvenile moult after fledging in late July , but some late-fledged second broods may not complete until mid or even late October. Juveniles take approximately 40 days to complete moult but the period for adults is unknown. Most migrants on passage through Hong Kong have fresh or slightly worn rectrices. Some young birds in Hong Kong in late August and early September are still growing their remiges and rectrices . As Oriental Reed Warbler does not breed in Hong Kong or neighbouring Guangdong province, these birds are perhaps involved in local coastal dispersal movements from elsewhere in southern China, rather than migrants from the northern part of the range, which would be expected to arrive later.

During winter, both adults and first-winter birds have a partial moult involving the body feathering. The timing of this moults appears to differ between populations. For example, Medway and Wells recorded heavy body moult in Malaysia during March and April . In Hong Kong. however, April passage migrants have completed moult and show a combination of old and worn primaries, rectrices and usually the tertials, which contrast with the usually fresh body plumage.


Grahame
 
First of all I want to apologise. To my defense I only can say it was 1 a.m. when the moult-idea struck me. I don't know why I didn't sleep over it and check some facts before posting. Sometimes it definitely is better to take a breath. Good to have Grahae who has the propper literature at hand ;). In fact it is in my library as well but for some senile reasons wasn't consulted beforehand. I surely complicated the matter, sorry.

So at this time of the year, it can't be the moult that influences the pp this much - at least not in ORW... Still I've learnt something. From Kennerly et al. I learnt that timing of moult in some CRW ssp. may vary depending on local rainfall. It may well take place now. Looking at the CRW in the link in post #12 and focussing on birds from late spring or summer when no ORW should be around reveals that harterti normally is indeed not as obviously shorter-winged than ORW as it seemed in the Reed Warblers in Valérys December thread. This can be explained by the fact that they were active wing-moult thus being harterti but not ORW I made my ID-assumptions basing on what I believed the normal pp of harterti would be.

Bearing that in mind I do not know anymore if the bird on pic 2 post #1 is an ORW. Is the pp really long enough? Other features like overall colour, bill shape and length I find difficult to use here. It does look greyer than I would have expected for a CRW though... but this seems to be variable

To come back to who started my mind carrousel (the bird on pic 1 post #1): After having watched photos of harterti I can't believe that this could be a CRW. To me the bill and face pattern (what can be seen) seems all wrong. Also the legs look too thin and with the wrong colour. But I may be wrong and it is almost midnight again. Perhaps I should leave it be...

BTW, I would love to listen to recordings from the Acros you have there!
 
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First of all I want to apologise. To my defense I only can say it was 1 a.m. when the moult-idea struck me. I don't know why I didn't sleep over it and check some facts before posting. Sometimes it definitely is better to take a breath. Good to have Grahae who has the propper literature at hand ;). In fact it is in my library as well but for some senile reasons wasn't consulted beforehand. I surely complicated the matter, sorry.

So at this time of the year, it can't be the moult that influences the pp this much - at least not in ORW... Still I've learnt something. From Kennerly et al. I learnt that timing of moult in some CRW ssp. may vary depending on local rainfall. It may well take place now. Looking at the CRW in the link in post #12 and focussing on birds from late spring or summer when no ORW should be around reveals that harterti normally is indeed not as obviously shorter-winged than ORW as it seemed in the Reed Warblers in Valérys December thread. This can be explained by the fact that they were active wing-moult thus being harterti but not ORW I made my ID-assumptions basing on what I believed the normal pp of harterti would be.

Bearing that in mind I do not know anymore if the bird on pic 2 post #1 is an ORW. Is the pp really long enough? Other features like overall colour, bill shape and length I find difficult to use here. It does look greyer than I would have expected for a CRW though... but this seems to be variable

To come back to who started my mind carrousel (the bird on pic 1 post #1): After having watched photos of harterti I can't believe that this could be a CRW. To me the bill and face pattern (what can be seen) seems all wrong. Also the legs look too thin and with the wrong colour. But I may be wrong and it is almost midnight again. Perhaps I should leave it be...

BTW, I would love to listen to recordings from the Acros you have there!

I've a new camera that makes great videos, I should try to use... I didn't try yet. No idea how it will record the sounds though.

I found a new pair of CRW in mangroves today, got both the males singing and female (photos - I will post if decent)... the most important for me is to learn about those really tough little jobs.
 
Usually cameras that can record videos have internal mics that are quite OK to record song or calls. Only there is no protection against wind and they are omidirectional (not focussed like e.g. a shotgun mic). That's why you would ideally try sound recording close by under circumstances as windstill as possible. There is freeware that can extract the sound from video or you just might upload a video on youtube. No need to actually see the bird even though I would complain of course ;)
 
Hi Roland and others,

Today I finally got mp4 of one bird singing. Poor view but we hear the sound. I've still to learn how to share: I've a limited 800mb internet per day and the file is 131mb; BF wouldn't upload such a big one anyway.

I'm sure I'll find the solution, in the meantime I share a photo of the bird I filmed so you can think of its identification. I write it clearly: it is NOT an ID request, that bird is positively identified already and I've got the song recorded.

Just hope you find the search of best features interesting.
 

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It seems after many attempts I managed; I hope the compression has not spoiled the sound quality (here it is excellent, except for the noise of the road). We can hear the typical sound of harterti. One can believe it is just a part of the song with only a few notes, but it is actually how it does all the time. Very far from the long an rhythmical song of Oriental Reed Wabler.
 

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It indeed sounds pretty much like A. stentoreus which were recorded in Phillipines exclusively; https://www.xeno-canto.org/235988, https://www.xeno-canto.org/321146. The higher frequency phrases are noticeably sharper than those typical song of A. orientalis. I would say with positivity that the individual is A.s.harterti.

Yes it is, I'm not sure if you read my message.
I write it clearly: it is NOT an ID request, that bird is positively identified already and I've got the song recorded.

I'm just trying to please Roland who asked me:
BTW, I would love to listen to recordings from the Acros you have there!

This is a first one...

By the way, I'm pretty sure harterti should be split from Clamorous (already split by HBW/Birdlife but grouped with Australasian).

Cheers B :)
 
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