This page provides the details of a mystery Warbler observed
by David Raju, a naturalist in Central India, from a
bamboo thicket near
Summary: A confusing Warbler which was observed
through out April near
David has added some critical behavioural information of this species which could well be used to pop up more individuals. The key observations are
“sticks to the upper canopy and rarely coming down to feed”,
“fans its tail very often much similar to Fantail or Monarch flycatcher”
and seems to have a “preference to mango trees and bamboo clumps”
The first photo made during the first week of April 2008 by
David was sent to me (Praveen) for confirmation labeled as
Certainly the picture is not good enough to id 100% but the supercilium
looks too obvious behind the eye for a
However, David Raju, who is familiar with Clamarous Reed Warbler (from Vembanad Wetlands, Kerala) was sure of the size and he maintained that it was not a Clamarous. He also informed me (via phone) the following information.
à Calls of the bird are somewhat similar to
à He could see a structure in the clumps, what he believes, is the nest of this bird.
à Meanwhile, he got hold of the sanctuary magazine with the observations of Large-billed Reed Warbler from Kolkota (by Sumit.K.Sen) and he seems to have observed in his bird “pointed tail feathers” and “fanning of the tail behaviour”.
By then, Mike has already brought in Bill Harvey, Philip D Round and Sumit K Sen in the loop and we were all waiting for the next set of photographs from David ; who is strung up in a far corner of Kanha N.P without a proper cell phone range and broadband/dial-up connectivity.
When the next set of three pictures arrived….
…with the following information passed via phone
à There are about 5 individuals
present in a set of bamboo clumps owned by the tour company for which David
works (he is a naturalist). He believes all are of same species (Note: Each
photo could have been
of a different individual).
à Apart from
à He saw on several occasions when the bird fanned its tail.
à Species seems to skulk in the clumps and photography seems to be difficult, according to him (photos made with Nikon D80 + Sigma 300mm lens).
à He has seen a structure among the bamboo clumps which he believes is a nest. He has seen the bird enter the bamboo clumps during the dusk and come out of the clumps at dawn (5:50 AM). It has not been possible to check if the bird has laid eggs (clumps are thick and it is not possible to check it without disturbing the likely nest) - however, he has not seen the bird brooding during any time of the day.He has also not seen "nest-building" per-se. There are several other structures in the bamboo clumps, smaller ones, which are also likely nests - perhaps of the more common Plain Prinias.
à The bird is most active till 9AM and then active at dusk. He also saw the bird chasing away Brown Shrike & Plain Prinia near the structure which seemingly he believes is a nest
However, at least one of the photos (last one), clearly showed a Syke’s Warbler (!).
these are Sykes's Warblers. 'Better' proportioned than
The tail fanning is interesting: not something I've heard of before but it could well be documented for other acro/hippo species. The nesting behaviour sounds much more like roosting than nesting. The song sounds like a bit of subsong which is to be expected at this time of year (I heard one this morning.)
Very interested in other people's opinions though. “
“Agree with Mike. Structure doesn’t fit Large-billed or Clamorous. There doesn't seem to be any firm evidence that the "nest" is theirs. A group of migrant warblers singing will also often display. Indeed they may be pairing up.”
David Raju, though disappointed, was still not very convinced. He kept going after the bird as it was found quite near to where he was put up. Around third week of April, he sent me the following pictures…
…along with, I also collected some information from him over phone.
à One of the visiting birders (Jonathan from
à In the earlier photographs, it is likely that he (David) muddled up the birds with Syke’s Warblers.
à Jonathan felt that this particular bird was Large-billed Reed Warbler
“I must say that to me these pics look much more convincing. They clearly show an acrop with a long bill, very short wings and large claws. These pics are very similar to the Kolkata ones last year.
As Large-billed has hardly ever been seen live in the wild could you ask David to provide much more detail on behaviour and calls. I assume he is no longer claiming it is nesting.”
“I find the bird very similar - however, I must mention that I have never seen the Large-billed with tail folded – every time we have seen it and every image obtained has the tail fanned out (sometimes a little - sometimes fully) - in fact when we saw it briefly this year that was the 1st thing we noticed - tail fanned out as it moved about. Does David have an image with an open/spread tail - that would perhaps, strike a stronger chord with my field views?”
Sumit K Sen
Tail-fanning behaviour of this Warbler
more interesting and more convincingly an acro rather
than a hippo having seen the most recent photos. (Clearly the earlier photos
did not all show the same bird.) Overall I'd say that it doesn't look quite as
large-billed as the photos of Phil and Sumit but
nevertheless does not really have either a
The tail fanning behaviour seems extraordinary - I don't know whether this is regularly recorded for other similar species or not but if it is as distinctive for LBRW as suggested (e.g. Sumit saying "I have never seen the Large-billed with tail folded") then it is particularly odd that the bird hasn't been recorded much more often.
Not sure when the first sighting was but the first email I received was on 7 April so it (or others?!) has clearly been there nearly a month, which would be particularly odd for a spring migrant.
I'd be interested to see some input from any acro experts.”
In another mail, David described the behaviour thus
“Its a high canopy feeder and rarely come down to feed. Anyway i will try to get more observations and photographs. Its behaviour like a leaf warbler. I saw the same species 30km away from my place and the same habitat & same tree (mango).They need good cover (canopy) to feed ,so i think if we search more in these area i will get more number. Anyway iam planning search similar habitat coming days. Iam making field notes which will help to know more about the birds’ habit.
He also sent across another six photographs taken along with the previous three.
“Indeed these are looking much more encouraging. The very latest six shots from David show well fanned tails and long claws.”
Some more extra information I received from David by phone which I circulated.
to be three birds in and around the property of his resort. The other sighting
which he mentioned (30km away) was the only other sighting. I quizzed on how he
is sure the birds are the same species - these
are the features he had based his identifications on..
à Fanned tail most times
à Pointed tail feathers
à Larger bill with entirely pale lower mandbile
à Similar behaviour - sticking to upper/middle canopy.”
Philip D Round, who was away, finally replied to the mailing thread with the following information.
“Thank you for kindly keeping me copied on the correspondence and for sending me the pictures. Sorry not to have played a larger role. I am probably not the person to make any judgment
of these since I have not seen Large-billed Reed Warbler in the field- only in the hand! Also, I am often reluctant to make definitive judgments from photos, even of birds that are much easier to identify than Acrocephalus. However, I think these later pictures seem highly plausible for A. orinus. What else could they be?
It is encouraging that David is getting such good observations on them in the field and is collecting behavioural information. Is the habitat just too tricky to net them in, or is there nobody close at hand with mist-nets and handling skills? It would be ideal if one could be examined in the hand and a tail feather collected for DNA.
One wonders what the seasonal status of the birds is. After two caught in late March, plus the observations from early April in Kolkata last year, I was working on the assumption that LBRW is an early spring migrant, suggesting that it breeds in the N Tropics or subtropics rather than in the Palearctic. So, why haven't these birds left already? Kanha is quite a way south, yes? Is there any possibility they might breed locally around Kanha?
I look forward to hearing more of this story as it unfolds.”
Philip D. Round
Thank you for sending this document and photographs to me for comment.
Based upon what is visible in the photographs, the bird is clearly an
Acrocephalus; the long undertail-coverts and rounded tail shape rule out
Sykes's and all other Hippolais species. I must stress that I have no
experience of LBRW so my comments must be read in this context. However, I
agree with that when everything else is eliminated, the only option
remaining is Large-billed Reed Warbler.
The points made on tail-fanning behaviour and apparent preference for bamboo
are interesting, and these may give valuable clues to finding them in the
I would agree with comments made that the early morning/evening behaviour
observed suggest a roosting bird rather than a breeding bird, and if
breeding, it would be likely that one or both adults would have been seen
bringing food to the bamboo clump now, since it is 6-7 weeks since the first
observations were made. Do you think it is possible that it could be a wet
season breeder, spending the drier months in central/southern
north - the two Tring specimen come from Rampoor, Himachal Pradesh on 13
November 1867 and Mussoorie, Uttar Pradesh, in October 1869.
What seems certain is that these recent records from
widespread than we could have imagined even 5 years ago. With observers
alerted to their appearance and behaviour, more records are likely and it
cannot be long until the breeding sites are discovered.
I wish you and your colleagues success in tracking down these elusive
In conclusion, the current status of this Warbler indicates
Large-billed Reed Warbler; however we might need more definite evidence before
the same can be confirmed. Meanwhile, these pages will hopefully trigger other
Many thanks to Mike Prince for having started the email thread for identification and providing several comments on its identification. Special thanks to Bill Harvey and Philip D Round who kept the enthusiasm on and provided key insights into the identification of this bird – and for encouraging David to provide further field observations and photographs which lead to the current conclusion - despite having received photographs of the wrong bird in between. It was quite useful to have Sumit K Sen comment on the behaviour of the bird - he being the only person in the world to have seen one in the wild. Peter Kennerley was able to comment on the bird after seeing this page – many thanks to him.
Text by Praveen J
Pictures by David Raju