Marsh Warbler? (1 Viewer)

[HH75]

Oh! And hand on heart?

Who can say they have had the luxury of checking this detail in the field?

"such as the (approximate) position of the emargination on the third primary, are not visible, at least not with any certainty, and some features seem to look better for Marsh in some pics than in others..."

That seems to have made its way into field guides from Ringing Manuals? It is NOT a viable field -character IMHO. Of no use, unless one has mist-netted the subject, and has had the luxury of checking feather tracts, etc. in minutiae!

2nd Collins is guilty of promoting this as a viable field character!

In photos this is difficult to assess also. Unless they show a wing-spread in a ringer's hand!

Ah, but this is NOT a bird in the field, this is a series of pics! I have often noted the position of the emargination of the third primary in good, sharp shots of birds in profile, and usually other characters have been clearly visible that backed up the identification suggested by the emargination.

I remain in the Marsh camp. With description of song fuelling my opinion.

That is your prerogative, but I put to you, as others have done, the following:
-unusually mimetic Reed Warblers can, and do, occur relatively regularly. Mimicry is not rare in Acrocephalus, and it seems that, as Marsh is such a renowned mimic, that a misconception now exists that any unstreaked Acro indulging in mimicry must be a Marsh. Without hearing the actual structure or tone of the song of the bird in question, I simply cannot form a firm opinion based on what the original poster has described with regard to the song: it could fit Reed or Marsh for me.
-to my eyes at least, on Marsh, and more so on Blyth's Reed, the supercilium, particularly the area in front of the eye (the supraloral), dominates the facial pattern, whereas, on Reed, the eye-ring is far more obvious than on the other two species. Now, in some pics of the discussion bird, the head pattern appears quite like that of Marsh (or Blyth's Reed), but, in the one that I linked to, the head pattern does remind me strongly of a Reed Warbler. I appreciate the subtle nature of this feature, and I may be guilty of forming an impression which differs from that of other people, but it does really suggest Reed to me over Marsh.
-as Hannu said, the longest tertial does not seem to be longer than the secondaries, as is usually the case on Marsh: this would fit Reed better.
-while leg colour is not foolproof, the brownish colour suggested on these pics would arguably fit Reed better.
-the claws seem as though they may have been long.
-the bill doesn't strike me as being as 'stubby' as on at least some Marsh.
-there are no obvious pale tips to the primaries.

Against all that, I think I am within my rights to await any further evidence before swaying toward the Marsh camp. You, of course, are perfectly entitled to feel otherwise.
Regards,
Harry

 

[phil baber]

Some great input from the Reed Camp! I guess mixed messages are coming from these photos. And as Harry said earlier? It is doubtful that a positive ID may be reached from these images alone? Yes, a recording of its song and more detailed photos would help. Thanks to all for some great breakdowns, analysis and informative links.

 

[jeff]

Many thanks for all your input and great links

I'll listen to Reed Warblers a little more from now on.

Details will soon be released, so guess someone with experience will catch up with it.

 

[hannu]

Some great input from the Reed Camp! I guess mixed messages are coming from these photos. And as Harry said earlier? It is doubtful that a positive ID may be reached from these images alone? Yes, a recording of its song and more detailed photos would help. Thanks to all for some great breakdowns, analysis and informative links.

I think that bird is possible to id in these pics 100%. We don't need description of song at all to be convinced on this species. By the way, I have never mix together songs of these two-three species, because songs really are so dissimilar in reality. Sometimes I have suspect some Blyth's Reed in the ligth of song, but after the catching they have been only Blyth's Reed. Harry made great collage of features, which should lead everyone to one conclusion.:t:

 

[gropperwinch]

I may well be wrong on this, but does Reed have such a steep sloping forehead? but having said that, wind can blow feathers back and change the shape of the head quite easily. Also olivey brown coluration makes me think more Marsh than Reed, as does eyering, but since a few of the features I'd like to see to make anything like a confident ID, rather than Jizz-based assumptions, are obscured/out of view a lot of the time (e.g the flanks), I'll admit probability plus the excellent points made by others, especially Harry, most likely make this a Reed, and I'll sit back, let anyone else voice their view and see if anyone from the Marsh camp can come up with something against the Reed camp's excellent fieldwork! :t:

 

[Periwinkle]

I went to see the bird this evening and I strongly believe the bird to be a Reed Warbler. It is indeed a great mimic (10+ species heard) and will spend periods just mimicing, other times it sang like a normal Reed Warbler and sometimes a mixture of both mimicing and reed. It gave occasional 'Marsh' bursts but never in a prolonged fashion. It seemed more inclined to typical Reed when other reeds were singing.

 

[gropperwinch]

That probably settles the case for me then, unless someone comes in with a late breakthrough to put us all to shame, I now think it is a Reed Warbler.

 

[jeff]

I went to see the bird this evening and I strongly believe the bird to be a Reed Warbler. It is indeed a great mimic (10+ species heard) and will spend periods just mimicing, other times it sang like a normal Reed Warbler and sometimes a mixture of both mimicing and reed. It gave occasional 'Marsh' bursts but never in a prolonged fashion. It seemed more inclined to typical Reed when other reeds were singing.

Many thanks, guess I wont be ticking it then if there's any doubt over it, but then again you told me there were no Marsh Tits at Ladywalk

 

[phil baber]

Get some better photos and a good recording of song Jeff. Then we'll start over again!

PS The bulging of the throat, while singing, is another plus point in favour of Marsh for me. That "bearded" effect has not been broached.
But then, I'm outnumbered here. I stick to my guns, and stay in the Marsh Camp. Based solely on the photo evidence.

 

[phil baber]

I think that bird is possible to id in these pics 100%. We don't need description of song at all to be convinced on this species.

Hmmmn?

100% Hannu?

Can you honestly say that this is a Reed, as opposed to a Marsh with the evidence available in the photos? 100%?

It seems, often, in these threads that overall ID is focused purely on "small details", yet the "bigger picture" of the bird, as a whole "suite of features" is often sparingly addressed.

I could, hand on heart, not claim that the bird in the photos is 100% Reed or Marsh. Blyth's obviously ruled out. But it is 100% in that species pair IMHO.

The fact that I feel it is a Marsh, from points I have raised, is based on my overall feelings about the photos, and the evidence I am personally seeing. But 100% is something I could not claim for either species in these images.

I wish you respect. But do not think this is resolved as yet. B

 

[hannu]

Hmmmn?

100% Hannu?

Can you honestly say that this is a Reed, as opposed to a Marsh with the evidence available in the photos? 100%?

It seems, often, in these threads that overall ID is focused purely on "small details", yet the "bigger picture" of the bird, as a whole "suite of features" is often sparingly addressed.

I could, hand on heart, not claim that the bird in the photos is 100% Reed or Marsh. Blyth's obviously ruled out. But it is 100% in that species pair IMHO.

The fact that I feel it is a Marsh, from points I have raised, is based on my overall feelings about the photos, and the evidence I am personally seeing. But 100% is something I could not claim for either species in these images.

I wish you respect. But do not think this is resolved as yet. B

Yes, I can honestly say, it’s Reed 100%. These pics are enough good to get sure id. I based my opinion on known differences in these species. Although we need some experience to catch them.

The bird should be darker primaries, if the bird would be Marsh Warbler. Marsh Warbler has blackish primaries, Reed Warbler has dark greyish brown primaries.

Because plumage of most Marsh Warblers is comparatively fresh in this time of year, I supposed to see some contrasting white tips in primaries too.

If this bird would be Marsh Warbler, I suppose to see some hint of yellowish buff colouration on the underparts ( throat, flanks, supercilium in these pics).

Also the overall colour of upperparts looks to me warmer (brown / weak rufous as in Reed Warbler) than greenish-olive tinge (as in Marsh Warbler).

The colour of distinct pale tertial edges doesn’t fit to the Marsh Warbler either.

The longest tertial does not reach beyond the secondaries either.

The greyish wash in head leads me to think that this bird is +2cy worn adult, very similar as in many worn adult Blyth’s Reed.

Such feature as head shape overlaps too much in these species and a rather useful feature as leg and claw colour is too difficult to estimate in these pics.

So I really don’t know what kind of evidences you will need to get most likely and (I would say) only conclusion in this case.

 

[Archie Archer]

I went to see the bird this evening and I strongly believe the bird to be a Reed Warbler. It is indeed a great mimic (10+ species heard) and will spend periods just mimicing, other times it sang like a normal Reed Warbler and sometimes a mixture of both mimicing and reed. It gave occasional 'Marsh' bursts but never in a prolonged fashion. It seemed more inclined to typical Reed when other reeds were singing.

It pains me to do it but I would have to agree with 'Pessimist Perrins' on this one. After a quick snatch of mimicry and initial views of the bird skulking around at the base of a willow the bird seemed pretty good for Marsh Warbler however I managed some very good views of it late on as it sang fully exposed and I would have to concur with Hannu's conclusion regarding a worn adult Reed Warbler.

As for the song I recorded the bird for nearly 20 minutes in total last night. An analysis of it's rendition concluded that just under 85% of it's song was typical Reed Warbler. Mimicry included Swift, Blackbird, Song Thrush, Marsh Warbler?, Sedge Warbler, Blackcap, Blue Tit, Great Tit, Goldfinch & Greenfinch.

So it looked like a Reed Warbler, it sounded like a Reed Warbler and it sang from a reedbed so I'd be pretty sure that the bird in question is not a Marsh Warbler.

Interestingly the bird seemed to have an influence on two definite Reed Warblers nearby that also chipped in with the odd bit of mimicry, maybe as way of 'keeping up with the Jones's'.

 

[jeff]

Many thanks for all the info. I'll pass this onto the country park staff so they can decide whether to close the area off again as I'm guessing there will be little interest now it's a reed warbler

Cheers

Jeff

 

[phil baber]

Maybe best not to post it on an open forum Jeff.

Get help locally, or from experienced "Marsh People". Trusted and reliable.

Sometimes a "potential" needs delicate treatment. And I know you have been careful!

But, we all must be mindfull that those who read these posts are not all people with the "best intentions."

I wish you very happy and lucky birding!

With best regards,

phil

 

[jeff]

Maybe best not to post it on an open forum Jeff.

Get help locally, or from experienced "Marsh People". Trusted and reliable.

Sometimes a "potential" needs delicate treatment. And I know you have been careful!

But, we all must be mindfull that those who read these posts are not all people with the "best intentions."

I wish you very happy and lucky birding!

With best regards,

phil

Can't see the problem with posting in a open forum, at no point was the location of the bird mentioned.
As you say I've been careful and respected the wishes of the landowner. It was only through the replies in the thread that answers have gained and we're all a little wiser now

Thank you to all those who did go and see the bird and gave their thoughts, but there were a lot of quiet experts out there

 

[Southern Frogmouth]

I am surprised that no one mentioned fuscus Reed Warbler to explain the plumage, but maybe that isn't considered necessary. In 2002 I think it was there was a bird at Little Paxton GPs that was originally IDed as Marsh. It was certainly pale and lacked rufous tone and I seem to remember very convincingly mimicked Common Tern and Redshank amongst others. I think that fuscus might be even more difficult to separate from Marsh - other than by song and structure, but I am not terribly experienced with this taxon.

 

[Jane Turner]

I think there is a trend for late arriving worn (hence non-rufous looking) Reed Warblers that are struggling to hold preferred territories, to compensate by upping the stakes in the singing dept. As far as i am aware, and recall, fuscus is no more mimetic than nominate.

 

[Southern Frogmouth]

Jane, you are correct. I can't remember where the reference is off-hand, but late arriving Reed Warblers are less rufous and seem to indulge in greater mimicry. It was the fact that fuscus is closer to Marsh Warbler in appearance than scirpaceus is that made me throw it into the mix as a possibility. Certainly a number of fuscus Reed Warbler have also been claimed recently in the UK, but this is probably due to the possibility of a split making people more aware of slight "differences", which actually are just part of the normal variation within a taxon rather than something more exotic.

 

[Southern Frogmouth]

P.S. I think it was BWP that actually mentioned the greater mimicry of late-arriving Reed Warblers.

 

[Archie Archer]

P.S. I think it was BWP that actually mentioned the greater mimicry of late-arriving Reed Warblers.

Just to let folks know that a mimicking Reed Warbler was trapped & identified at the location today. We are now entering the realms of the old 'two bird theory' unfortunately.