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Raptor with white bits, Benacre, Suffolk (1 Viewer)

This is what the Forum is all about to me. All this in-depth discussion is fascinating. Thanks to all the above posters. I don't care if this bird isn't identified. The process is so interesting. You are a clever lot!

Sandra
:clap:
 
Jane, I judged the wing formula from pic2 and I honestly don´t thing that there´s a 1st primary so well hidden that we can´t see it from there. In your close up of the wing tip it looks like some fraying of p1. The broader fingers mentioned by Andy is a good point:

http://www.netfugl.dk/pictures.php?id=showpicture&picture_id=11615

http://www.netfugl.dk/pictures.php?id=showpicture&picture_id=1940

but can look diferent in another pose: (looking at images)

http://www.netfugl.dk/pictures.php?id=showpicture&picture_id=1939

JanJ
 
Real Grosser on my list said:
OK. Now try matching a Marsh harrier to the first shot of the Benacre bird!
Cheers,

Andy.


I love a challenge! This is the best I have found so far.
 

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Jane Turner said:
I love a challenge! This is the best I have found so far.

Yeah, that's not bad. But then that isn't the first pic!

Logic would suggest that this bird is a Marsh Harrier but there is so much wrong with this bird that it makes it difficult to accept it as such. It requires some huge leaps to get to that conclusion.

I don't think I can add anymore to this debate.

Thanks to Jane and Janj aongst others for their useful comments. Nice pics Megaquetzal - what's your set up?

Cheers,

Andy.

ps - For ***** ****, It is NOT a juv! (nasty Grosser)
 
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I don't know if this helps or not..... but I can only see 9 primaries on the right wing of this bird. The first secondary is marked.
 

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Real Grosser on my list said:
Yeah, that's not bad. But then that isn't the first pic!

Good grief - you don't want much do you. :eek:)

This is my best yet. Its not exactly the same pose, since its banking at a slightly different angle, but I'd argue that if you wanted to rule the Benacre bird out on wing shape/primary then you'd be arguing that the lower bird wasn't a marsh harrier too.
 

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Jane Turner said:
I don't know if this helps or not..... but I can only see 9 primaries on the right wing of this bird. The first secondary is marked.

Yes Jane, in 1st pic it looks like it, but the same wing in pic2 clearly shows 10 primaries, counting from outwards. It seems to be two more primaries (shapewise) after the one with a white mark inside the white tip as far as I can see.

JanJ
 
Jane Turner said:
Good grief - you don't want much do you. :eek:)

This is my best yet. Its not exactly the same pose, since its banking at a slightly different angle, but I'd argue that if you wanted to rule the Benacre bird out on wing shape/primary then you'd be arguing that the lower bird wasn't a marsh harrier too.

...out of retirement......

Yeah, that's good. But the comparison shows that the Benacre bird has the head of a buteo and not Harrier!
 
Sandra (Taylor) said:
This is what the Forum is all about to me. All this in-depth discussion is fascinating. Thanks to all the above posters. I don't care if this bird isn't identified. The process is so interesting. You are a clever lot!

Sandra
:clap:


I'll second that! Thanks for all your efforts. I hope someone else gets good views of the bird in the field and can come up with some better diagnostic photos.
 
Real Grosser on my list said:
Yeah, that's not bad. But then that isn't the first pic!

Logic would suggest that this bird is a Marsh Harrier but there is so much wrong with this bird that it makes it difficult to accept it as such. It requires some huge leaps to get to that conclusion.

I don't think I can add anymore to this debate.

Thanks to Jane and Janj aongst others for their useful comments. Nice pics Megaquetzal - what's your set up?

Cheers,

Andy.



ps - For ***** ****, It is NOT a juv! (nasty Grosser)

Canon 350D, Sigma 170-500 and shakey hands!
 
Real Grosser on my list said:
...out of retirement......

Yeah, that's good. But the comparison shows that the Benacre bird has the head of a buteo and not Harrier!


Would that be the sound of moving goal posts?

Agreed its look Buteo-ish on the first pic - Its why I didn't jump on the Marsh Harrier bandwagon straight away. It does however look perfectly OK for a Marsh Harrier in the second set of pics. I suspect if they had been the first picts posted there wouldn't have been much of an argument.
 
Hi All,

Yikes! What an interesting bird. Now I can see why there were so many posts and views on this thread. I am really weak on my Marsh Harrier identification, but was wondering about a few points that have come up along the way.

With the caveat that I still get myself tripped up with ageing birds on a regular basis, I am thus far finding myself in the camp that feels this is a first cycle bird (thus a juvenile) rather than one in a later cycle. I don't see any active molt centers and I'm not picking up on any feathers that are of an obviously newer generation. Why not a bird that was hatched in May-June that is now some 3-4 months old? I agree that this bird looks really frayed, but I wonder how much it really is. As with a few other parts of the bird, the remiges have quite an unusual pattern to them, with white tips to many, but with narrow dark streaks extending out to the tips in some cases. There is some fraying for sure, but some of it may be an illusion created by the pigment distribution itself. Since the frayed areas seem restricted to the white patches, it seems reasonable that they could be fraying prematurely due to pigmentation deficiency as others have suggested.

JanJ and Grosser have mentioned the thickness of the primaries being off for a Marsh Harrier. Assuming for a second that it was a juvenile, would that go some way toward explaining the narrower shape to the primaries? It seems like Megaquetzal and Joe's comparative shots show similarly shaped primaries.

As far as potential North American Buteo and Parabuteo go, I think that Harris's Hawk has been reasonably axed. While the bird has some real similarities to Swainson's, there are some real odd features to this bird that I've never seen on Swainson's. First off, Swainson's Hawks frequently exhibit white uppertail coverts, which this bird does not despite having a good deal of white elsewhere. Also the tail lacks any dark tail-barring, which I believe is a feature of all ages of Swainson's. It would be really unusual to see a Swainson's where the wing linings were not noticeably paler than the remiges, and I believe that the remiges should always be barred in that species as well. So anyway, it doesn't add up easily for a Swainson's.

There are a few features that seem reminiscent of Marsh Harrier to me, at least superficially. The general tone of the plumage is plain and dark, without any barring to remiges or rectrices (as with juv. Marsh Harrier), and the uppertail coverts seem to have a tawny cast to them, contrasting with the darker, browner, but tawny tipped rectrices. This also seems to be a really good fit for a juvenile Marsh Harrier (cf. plate 181 Forsman's Raptors of Europe and Middle East). Joe's image in Post #20 shows this somewhat too. Also, is there any import to the shape of the tail? It has slightly concave sides and narrow base when fanned, and seems a good match for at least some of the Marsh Harrier images I've looked at.

Also, there is the nagging behavioral comments from Megaquetzal that the bird looked and behaved like a Marsh Harrier, and it was not until he looked at his images that he was struck by the unusual patterning.

This is a definite head-scratcher, and I'll leave it to those with more experience to work out what it is. But I can still imagine it working out to be a rather weird juvenile Marsh Harrier.

Chris
 
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Chris Benesh said:
Hi All,
I am thus far finding myself in the camp that feels this is a first cycle bird (thus a juvenile) rather than one in a later cycle. I don't see any active molt centers and I'm not picking up on any feathers that are of an obviously newer generation.
Chris

If you look at the close up shot posted earlier, you can see that the wear is extensive throughout all the secondaries and the inner primaries.

You MUST find other examples which show that wear of this nature can occur in a fresh juvenile. Go look at shots on Surfbirds and even posted here of juv Marsh and you'll see how fresh they all look. Without backing up this claim with examples, reference to text or other birds seen in the field it becomes worthless. Sorry.

My thinking is that this is an escaped bird which explains why it hasn't begun remex moult. I can provide many examples of birds in mid-late summer in remex moult if necessary that back this up. Revisit the Monties Harrier thread in Northern Ireland where plenty of pics of moulting birds were posted.

Have a look at the Red Foot shot I posted on this tread earlier which shows the effects of long term wear similar to that of the Benacre BOP.

the second set of shots are not as good as the first and add little to the debate.

I do, however, note Megaquetzals comments about the way it fed.

Someone send this to Forsman........
 
Real Grosser on my list said:
You MUST find other examples which show that wear of this nature can occur in a fresh juvenile. Without backing up this claim with examples, reference to text or other birds seen in the field it becomes worthless. Sorry.

Hi Grosser,

You will get a proper response from me in short order, but in the meantime, check the nasty Grosser at the door please!

Chris
 
My gut reaction when seeing the photos was a MH. Having read through all the posts I (still) haven't seen anything that would make me change my mind, even if it certainly is a strange looking individual.

And I'd have to agree with Jane in terms of using wear as a reliable tool for juding age in albinistic/leucistic birds. It has been known for quite some time that melanin is associated with strenght, although the exact circumstances on how this is achieved are somewhat questionable at this point (some have theorized that it actually is the melanin in the keratin that results in increased strength, others that it is caused by structural differences that only indirectly are linked to melanin... and a few other theories). Anyway, regardless of the exact details one thing is clear: Using wear as an indicator of age in albinistic/leucistic individuals is highly unreliable.
 
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Jane Turner said:
As I said before I don't think its safe to make age/wear judgements on leucistic/albino birds.

In this case I think we may be able to; if the bird was 2cy (1st summer) or older then surely at this time of year there should be some evidence of moult. Anyone who is in an area with Marsh Harriers (sadly lacking up here) could check this out but I expect that the only birds with all feathers of the same generation, and no sign of active moult, in mid-September will be juvs. If the bird is an aberrant juv MH then it could be feasible that the remiges are so worn because of the friability of pale feather tips. It does look pretty knackered though - like it's been battering it's wings against the bars of a cage maybe?

martin
 
Rasmus Boegh said:
My gut reaction when seeing the photos was a MH. Having read through all the posts I (still) haven't seen anything that would make me change my mind, even if it certainly is a strange looking individual.

And I'd have to agree with Jane in terms of using wear as a reliable tool for juding age in albinistic/leucistic birds. It has been known for quite some time that melanin is associated with strenght, although the exact circumstances on how this is achieved are somewhat questionable at this point (some have theorized that it actually is the melanin in the keratin that results in increased strength, others that it is caused by structural differences that only indirectly are linked to melanin... and a few other theories). Anyway, regardless of the exact details one thing is clear: Using wear as an indicator of age in albinistic/leucistic individuals is highly unreliable.

Strangely, in another life, I have worked on the X-ray diffraction of keratin (in human hair), specifically looking for the degree of crystallinity. In fact the very thought of this is bringing back throat clogging smells of developing fluids and the memory of night after night of inadequate sleep and the incessant bleeping of the interlocks at the Synchrotron facility at Daresbury!

Off to ponder!
 
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