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Unusual Cormorant, London UK (1 Viewer)

Clarke Robinson

Well-known member
Hi Everyone

After coming back to London after Christmas, the weather picked up today and we went for a walk round our local patch in Kensington Gardens. I'm still definitely in the novice category with birds, but found this cormorant unusual. Is it an adult in full breeding head-gear for want of better words? Or a juvenile of some sort? Or an old bird turning grey? lol

Any info appreciated.

P.S. This is the best picture I got, I was disappointed with the quality but got some nice Robins later so made up for it somewhat.

;)
 

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You need a close up of the gular angle to be certain - but plumage wise this looks like an adult of the race sinensis, which is happily establishing itself at inland locations in the UK.
 
A very nice spot for a "novice"! Congratulations!

Steven (or anyone), how common have these become in the UK? I've not seen one up this way yet but are we talking about an invasion of Med Gull or Little Egret proportions now?
 
Hi Graham

I saw a couple in Sussex last March and we had one up here in the Spring last year too

D
 
bitterntwisted said:
A very nice spot for a "novice"! Congratulations!

Steven (or anyone), how common have these become in the UK? I've not seen one up this way yet but are we talking about an invasion of Med Gull or Little Egret proportions now?

Here is the knowledge you seek


ID and status
http://www.paxton-pits.org.uk/cormorant/id/

More high brow stuff on status of sinensis
http://www.jncc.gov.uk/pdf/UKSPA/UKSPA-A6-11A.pdf
http://www.ncbi.nlm.nih.gov/entrez/...ve&db=PubMed&list_uids=11298814&dopt=Abstract
 
Fascinating. A Continental Cormorant. Here's another pic I took, hope this doesn't confuse matters as the white head doesn't appear just as strong on this one, even though it is the same bird. Hope this helps...
 

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Thanks for the links, Jane. This seems like another one where things are much more complex than "common knowledge" and my assumptions indicated. In the good old days our birds had black heads and the funny foreign ones had white heads. Not any more!

If I've got this right, white-headed birds may be more likely to be "continental" (sinensis) than "british" (carbo) but this is not a good criterion because of variable amount of white in both subspecies, with both subsepcies only showing the feature up until egg-laying. And in fact to be sure of ID you need a protractor and an understanding of the "gular pouch angle" - that diagram is rubbish - anyone else explain exactly what's being measured?

Clarke, sorry if my congratulations were premature. The more you learn with this shenanigans, the less you find you know!

Graham
 
No need for apologies, I find this very interesting indeed. My only regret now is that tomorrow's Monday, and with work I won't get another opportunity to see if this bird hangs around for some better pictures. Will it still be there next weekend? Will the sun shine? The joys of shooting birds (erm....with a camera, not a rifle!) lol. Thanks again to everybody for all the insights!
 
Agree with jane looks more carbo maybe. Also agree with Graham things are never simple these days in birding, bring back the good old simple days I say. ;)

Interesting bird non the less, also its whetted my appetite, there is cormorant roost on my local patch that I usually only view through bins, must take my scope next time and give them a grilling.
 
This is how I do it.... no need for a protractor. On sinensis - which is also smaller to the point of being confusable with Shag, if you drop a line from the gape line down the back edge of the gular patch it goes nearly vertically. On carbo, the line slopes back towards the bill tip. This bird is the centre one - sinensis on left and carbo on right.

You only need to be able to imagine that the bird has its bill held horizontally!
 

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The bird looks exactly like a Great Cormorant from Abberton Reservoir (in Essex) that has been returning to the southeastern Netherlands for years: gular pouch like carbo, but a white head more expected for sinensis.
Although that bird has now been accepted as carbo (based on its pouch shape), I just found some old e-mails in which one of the researchers at Abberton Reservoir states that a hybrid origin cannot be excluded. And that might be the case with this one as well!
 
Jane Turner said:
you drop a line from the gape line down the back edge of the gular patch it goes nearly vertically.

Fantastic, Jane! Really useful montage. This is going up in my bird club hide in place of the diagram you linked to. I asked other members about that diagram a few months ago. They said "you don't wanna know".
 
Jane Turner said:
This is how I do it.... no need for a protractor. On sinensis - which is also smaller to the point of being confusable with Shag, if you drop a line from the gape line down the back edge of the gular patch it goes nearly vertically. On carbo, the line slopes back towards the bill tip. This bird is the centre one - sinensis on left and carbo on right.

You only need to be able to imagine that the bird has its bill held horizontally!

Thanks very much for this. I read one of those articles a year or so ago when I made a similar query about a white-headed cormorant and had no idea what they were on about. I now understand! Thank you, Jane.

Helen
 
Jane Turner said:
Those are sinensis Graham

Thanks Jane. Just looked in my guide and it says the entire Baltic population are probably sinensis. Is there a lot of variation in the amount of white on the heads of breeding adults. I haven't seen many that white. Or have I just been unobservant?
Edit: I see Graham's already answered this question.
Graham
 
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Here is a clearer version of the diagram with the gular patch highlighted in orange - the human eye is great at spotting the near 90° of sinensis
 

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