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

Hi All,

I'll skip any commentary on the harrier/buteo whatever for the moment, but I simply wanted to state that Birdforum is a place for birders of all levels. It is a community of birders, and it is not a place reserved for the experts. The diversity of opinion and experience is its strength, not its weakness. As contributers, we should make every effort to be inclusive rather than exclusive. Birdforum is a great learning place for any birder self confident enough to post photos or descriptions of mystery birds, and for others self confident enough to chime in with what they feel a particular bird is. Sometimes it is knee-jerk "Jedi" birding. So what? Someone generally comes along and offers up another possibility if the knee-jerk seems misplaced. If no one does, take initiative and set everyone straight, but in a constructive, tactful manner. I suspect that one stands just about as good a chance of getting an ID worked out here at Birdforum than in just about any other cyber forum, though the process might work a bit differently.

One thing I would like to see more of on this forum would be for contributers to more consistently explain their positions. It is not always necessary, but if someone posts a picture of Bird X wondering if it is X,Y, or Z, they are probably also searching for the reason why.

And lastly, even if you feel the person you're in disagreement with is out-of-touch with reality, try your best to keep those thoughts to yourself. It really serves no one for that sort of vitriol to get slung around. Many birders get easily put off when their opinions and expressions are dismissed in a callous manner.

Chris

Grosser,

While you undoubtedly are no slouch when it comes to ID I feel that the 'suspended moult' argument is wrong in the case of this bird. Yes, suspended moult does occur and yes, some species complete the moult in the winter quarters. Indeed, some moult almost entirely in the winter quarters. However, suspended moult cannot leave a bird with all of it's remiges of the same generation. Suspended moult should be evident in the remiges. S1, S5, S11 and P1 at least should be newer feathers. I still believe that the last moult this bird had was complete, hence all of the remiges/rectrices being of the same generation. The fact that all of the flight feathers are of one generation still, I think, causes problems with ageing this bird as anything other than a juvenile.

I sent a link to this thread to a few friends/colleagues with a vast amount of raptor experience.

Here are the replies I've received so far;

1) From a raptor worker in Britain (not a BF member, and I'm not going to reveal his identity)

"Just had a quick look at the bird I see your dilemma. I think that it's an odd juv marsh harrier. It's plumage does look all one generation with no moult, its
got that very dark chocolate coloured plumage...........its tail shape looks a bit short but is this just the photo? ............plus, on the first look, my gut reaction was a harrier but I could be wrong !!!!!!"


2) From Mattias Ullman in Sweden

"The bird is a marsh harrier and most certainly a juvenile bird.
As you say, feathers are all of the same generation, secondaries and
primaries are blackish (an older female would have more brownish remiges)
and the bird has white tips (of the same generation) on the tail.

I have seen juv marsh harriers with "strange white areas" at least twice
before in Sweden (on the belly and the head), although not as extensive as
on this bird (and not on the remiges either).
Obviously this is some kind of partial leucism.

Once or twice every year you also see juvenile birds with totally dark head
(i.e. missing the yellow on the crown)."


I'm still waiting on the reply from a Danish raptor expert, which I'll post here when I receive it.

Do you have a reply from Dick Forsmann yet?

cheers
martin

I was going to post that there was no apparent moult to be suspended too Martin but thought better of it this morning, the way things were going. Delayed / Postponed but not suspended. Minor point, maybe.

good to see people getting on a bit better...

Tim

Andy,
Yes I agree with what you say.
Have just read Chris's comments above so won't go over it again...as usual he hits the nail on the head.
Its not my way to have no evidence ! Its the evidence that I/we learn from. Long may it continue.
But lets leave room for everyone without alienating those who could be upset/put off by the sniping.
You said you would be sacked if you produced reports like some here (I paraphrase from memory) I hope you can see that I come from an environment where I would be sacked if I responded to others the way you can do sometimes!!
Look forward to the next difficult thread with you - promise I too will give as much evidence as I can muster if it is needed.
All the best - Halftwo.

As much as I agree with the said here about the 'Mr himself', but also what he is refering to as the need to find more evidence to support opinions, or as Chris puts it, consistently explain ones position (which I my self not always do, sometimes due to lack of time, sometimes due to lack of relevant knowledge), this will soon develop into a thread about Andy and his misbehaveing

So, how to deal with that? Do what he wants, and if you can´t slap him, but gently and remember that 'no human behaviour is strange to you'

I´ll B to that, and all contributers to this forum!

JanJ

Ill drink to the rehabilitation of Cameron and some other birders living on a lump in the ocean

cheers people

gently this pint B

I recieved this today......

Thanks for your email - I think there is a real possibility we could have seen the same Marsh Harrier, based on the second image. I first saw the bird several weeks ago at Titchwell, then again more recently which you presumably saw on my sightings page. The upperwing pattern recalls juv Spotted Eagle, with uniform white tipping on the wing coverts and flight feathers. I don't recall any white on the body, though all my sightings have been rather distant - it was at Holkham freshmarsh on Mon 2nd October.

..........I wonder what happened to the other two from this year's brood!

As a self-declared non expert, I have to say that to me this still looks really odd for marsh harrier...

But I can say that. This thread wasn't started by someone making a claim to some great rarity which warrants intensive scrutiny and weight of evidence to prove a claim - it was simply a request for help with an ID.

Some people in this discussion seem to have lost track of that fact...

I think Halftwo has been trying to make a similar point.

I must admit to being amazed as to how this thread has developed over the time since it was initially posted. The amount of effort that has gone into attempting to get a good (and unanimous) ID is impressive. Looking through the last couple of pages of replies I was stopped in my tracks when I saw the photo of the bird taken at Minsmere posted by Jane. This to my eyes has the closest resemblence to the bird that I photographed at Benacre.
Thanks again for all your efforts. <M>

As an interesting addition to this, i recieved the following reply from Adam Rowlands at Minsmere.

"Hi Paul,

Not sure when these photos were taken, and therefore how relevant the feather wear is, but I would agree with your ID. I'd imagine the white tips wear faster than the normally pigmented feathers, hence the greater than expected feather wear. The following link has images of the 2005 Minsmere partially leucistic young (although you may need a Birdguides login to view them??):

http://www.birdguides.com/birdnews/...Month=0&endYear=0&notes=&contname=Mike+Parker

There were five young in this brood, which varied from as strikingly marked as the photographed birds to normal plumage. We had another brood this year, at least one of which showed a white belly like your photo'd bird.

Hope this helps!"

So circumstantial evidence (and i agree its not definitive) would suggest this bird was actually born at Minsmere to a pair of Marsh Harriers regularly producing partially leucistic young.

I should add that Adam is also a member of BBRC

Chris Benesh said:

I don't know Dick Forsman personally (nor have access to his email address), but I did send along the pictures to another raptor expert who I do know personally, Bill Clark, who has done a fair bit of work with European Raptors and is cited in Forsman as authoring or coauthoring two articles pertaining to Marsh Harrier identification. I will certainly inform this thread if I hear back from him.

Click to expand...

Hi All,

Sorry to resurrect this thread, but as promised, here is the response that I just got back from Bill Clark who had been travelling recently. It corroborates what seems to be the majority opinion.

Chris

Bill Clark said:

Hi Chris,

This is definitely a juvenile female Western Marsh Harrier, /Circus
aeruginosus/. It is, as Frenchy suggested, a dark-morph that is also a
partial albino. Steve Waite, Harry Hussey, and Simonph were in agreement
as well. It is definitely not a Harris's Hawk nor a Swainson's Hawk.

Thanks for sharing this with me. Please feel free to post this on the
web site.

Cheers, Bill

Click to expand...

Hi all,

I have now had a reply from Dick Forsman and he is certain that this is a juvenile Marsh Harrier.

Whilst I am still not 100% convinced, I must admit that the wealth and weight of opinion is overwhelming and I would say that the only logical solution is that this bird can only be a juvenile Marsh Harrier. Martin Kitching's comments concerning moult are also very persuasive and the fact that this bird was photographed at a site where a pair of adult birds regularly produce partially albinistic young pretty much proves the ID.

I still haven't caught up with Lesser Canada Goose and I'll be heading up to Caerlaverock some time in the winter. I'll be watching the bird in fancy dress. I'll post the pictures here.

Cheers,

Andy.

Good on you mate!

Oh - seeing the update here has just jogged my memory...

Whilst in North Norfolk last weekend, there was at least one juv Marsh Harrier showing broad off-white feather fringes over the freshmarsh at Holkham - extremely striking, and very similar to the birds photographed at Minsmere. Presumably this was a local bird, so I guess it adds weight to the theory that there are a number of partially leucistic MHs floating around in East Anglia.

Looking forward to those photos...

Me too! Nice-one Grosser!

dbradnum said:

Looking forward to those photos...

Click to expand...

no ones considered that it may be a dark phase buteo lagopus?

motacilla oenenthe said:

no ones considered that it may be a dark phase buteo lagopus?

Click to expand...

If you read all x amount of posts on this thread, you'll see that most of the worlds raptors and hybrids have been mooted at some point. Dark phase B. lagopus are unknown outside of North America, as far as i know, so we can rule that out. As well as the fact that it looks just like a Marsh Harrier with white bits, we know there are leucistic birds being born within 5 miles of where the bird was photographed, and two of the worlds leading raptor experts have agreed with the fact that its a Marsh Harrier!

Anyway, we've been here for a long while now, so i vote the mods stick 4 stars on this thread, and we all look forwards to the fancy dress photos

You can stick the stars on it, Frenchy - top right of the screen, there's a "Rate this thread" button. I'll leave it to you to decide just how good this one's been!

Well, every day's a school day!

Always wandered what the criteria were for "starring" a thread, and now i know. Cheers!