Gull ID please...

[Marko Matesic]

I am not sure which gull this is if anyone can help.... please be kind and help :)
Photo is taken at delta of Mirna river in Croatia(europe)
http://img146.imageshack.us/img146/115/mg2632pm2.jpg
thx for looking and help!

[Jeff Wear]

ring-billed gull that would be my shot at the ID

[Marko Matesic]

Thx Jeff if that is correct this would be third time that they are seen in Croatia they are very very rare here ....last one is seen in 2005...

[Dave Brown]

Hey,

First off, do you have any more pics- anything that shows the upperparts perhaps. Gull identification can be very tricky and sometimes multiple angles are needed. Given the rare status of Ring-billed Gull in Croatia I'm certainly not prepared to identify this bird yet. I would like to get more of your thoughts on the bird. What do you think it is?, Why?, how big was it compared to Herring Gulls etc.This information would be most helpful. I do have some further ideas on an identification but i'll save those for now.

Dave Brown

[Dan Brown]

Hi Marko. After consulting my copy of "Gulls of North America, Europe and Asia" by Klaus Malling Olsen and Hans Larsson, I think that this is a third winter Lesser Black-backed Gull, Larus fuscus. The ring on the bill is present in LBB in the third year. Also the single white spot on the outer primary, the under wing pattern, nape markings, eye color, and leg color look good for LBB.
Lets see what others with more experience than I think:D

[Dave Brown]

Hi,

Based on the small visible portion of the birds far wing, the bird appears far too pale for even the lightest mantled LBBG (Graellsi). Larus fuscus fuscus is the darkest form of LBBG, pretty much matching Great Black-backed Gull in mantle shade. Still waiting for further details. Before we even attempt to identify this bird we should first age it- an important first step in gull identification. Ideas anyone?? More from me later...

Dave

[Dan Brown]

Hi,

Based on the small visible portion of the birds far wing, the bird appears far too pale for even the lightest mantled LBBG (Graellsi). Larus fuscus fuscus is the darkest form of LBBG, pretty much matching Great Black-backed Gull in mantle shade. Still waiting for further details. Before we even attempt to identify this bird we should first age it- an important first step in gull identification. Ideas anyone?? More from me later...

Dave

Good point Dave. For what it's worth, I am looking at the plate in my above mentioned guide and it is showing me that the upper wing tone of the third winter LBB graellsi is very close to the small visible portion of Marko's bird IMO:confused:

[Marko Matesic]

Hi and thx to all :)
@ Dave...sorry this is my only photo from that session.....I cropped more that you can see more details...
I send it to my friend ornithologist and he thinks that is Yellow-legged Gull in the third year(very common in Croatia) but hi is not sure 100% ...he also needs more pictures that I don`t have :(
Size approximately matches Yellow-legged Gull maybe little smaller I think...but it is hard to see while in flight....and I noticed that hi is different when I see picture on monitor!?!
here is bigger crop...maybe with more details
http://img171.imageshack.us/img171/9272/mg2632cropedvv9.jpg
thx for help!

[John Chardine]

For reference, here is a Ring-bill (top) and young Herring Gull (bottom) created a couple of weeks ago on Cape Breton Island. I'll let people mull this over for a while. Like Dave I have an idea too, and maybe these images give it away!

Fun isn't it!

[john jackson]

Hi Marko

Despite the striking superficial resemblance to Ring-billed Gull, I have to agree with your friend and say your bird is a Yellow-legged Gull. The wing tip matches that species, and the grey underside to the primaries and secondaries discount Herring Gull.

John: nice to see some American Herring Gulls as this form has been split recently from 'our' Herring Gull. UK birders are still fumbling around on how to identify birds older than first year.

Cheers

John

[Richard Stern]

Hi,

If it were a Ring-billed it would have to be an adult, from the plumage - and therefore should have yellow legs. It doesn't - the legs are pink. Also the bill looks too heavy for a Ring-bill. What time of year was the image taken? By this time of year most Ring-bills will have heavy streaking on the head, while Y-L often don't. I think the mantle is too light even for a graelsii LBBG. So I'll go along with 3rd c. Yellow-legged.

Interesting bird!

Richard

[Wayne Richardson]

Hi Marko

A very interesting post.

We need to consider what large gulls you would expect to see at the location where your image was obtained. Croatia is outside the ‘normal’ winter range for Lesser-black Back Gull, i.e. SSP intermedius or graellsii & a considerable distance away from European Herring Gull haunts. On the other hand, the country is almost centrally placed within the range of the resident Yellow-legged Gull & also within the ‘post-breeding’ dispersal range of Caspian Gull.

Size/plumage details would rule out Ring-billed Gull & it has been pointed out that many sub-adult gull species have a ‘ringed’ bill.

Mantle shade is important & the Kodak Grey Scale for the species mentioned here & in other posts follows in ascending order:


Caspian Gull 4 to 6.5;
European Herring Gull 4 to 8 with Northern birds being the darkest;
Yellow-legged Gull 5 to 7;
Lesser Black-back Gull graellsii 8 to 11 ;
Lesser Black-back Gull intermedius 11 to 13

Other important ID features are the under-wing pattern, head streaking, eye colour & leg colour. The bird appears to exhibit both 2nd & 3rd calendar year features, although it isn’t unusual given immature gulls are notorious for their individuality. However, there doesn’t appear to be any dark feathers in the tail which is an adult characteristic. I therefore don’t think this bird’s identity is quite as straightforward as some appear to imply from their comments. ;)


NB The taxonomic status of the Herring/Lesser Black-backed/Yellow-legged complex has recently been revised by several European bird committees & I’ll post a summary on a separate thread.

[john jackson]

As Wayne states, the 'in-range' options for large white-headed and pale-mantled gulls in Croatia are limited to Yellow-legged and Caspian Gulls. By this age, Caspian would, I think, show fingers of grey reaching into the black wing tip. Also, the bill looks a little heavy and the eye large and pale for Caspian.

[Dave Brown]

Lets start by aging this thing. Based on the lack of dark smudging or streaking on the underparts, underwing coverts, tail, as well, the the paleness of the eye, I think we can safely say this bird is at least 3 years old.This complicates some due to the inherrent variation in immature gulls.

Before I answer I will say that I have no experience with Michahellis Yellow-legged Gull( if YLGU this would have to be Michahellis based on mantle shade). I do have experience with atlantis YLGU,which is annual in St.John's each winter( 1-2 birds). I feel entirely confident saything this is not a RBGU for reasons asready mentioned. Based on the lack of white "tongues" in the primaries and single window on P10 I think we can eliminate Herring Gull. I agree that the two real candidates here are Caspian and Michahellis Yellow-legged Gull. I feel the primary pattern is fine for Yellow-legged gull, Black primaries form P10- P6 and anice thick band on P 5 is good- lack of black marking on P4 is also good. The pale eye is good it seems to me (although I've never seen one in life) that even most adult Caspian Gulls would not show an eye this pale. The bill appears to be blunt and thick, really good for YLGU, whereas I would expect Caspian Gull to have a somewhat pointier tip. The black marking are totally fine considering the age. Something to note is that it appears that the outermost primary is still growing on this bird. I haven't consulted the OLser- Larssen guide but there are possibly differences in moult timing between YLGU and CAGU. The only thing that really bothers me about this bird is the lack of and position of the head streaking. CAGU are well known for having collard head streaking as displayed by this bird, while YLGU head streaking tends to be restricted mainly to the head, but again this is an immature gull and that of course can vary.

So I guess I'm leaning very much towards the YLGU camp but I am not 100% in this id. If you want to be positive you could post a link to the ID Frontiers newsgroup that can be found at www.birdingonthe.net (http://www.birdingonthe.net) . There are a number of European gull enthusiasts that could perhaps nail an id for you.

Dave Brown

[Marko Matesic]

Thx to everyone....
I did`not think that this post will be interesting for everybody......
In the meanwhile I received another vote for YLGU from another friend (also ornithologist)....so probably YLGU it is...
it is great to be here on the forum. It is very educational and I learn a lot from you guys....thx for sharing your knowledge

[John Chardine]

Gull ID is always interesting Marko!!

[Wayne Richardson]

Hi Marko

I’m posting this image of a 3<SUP>rd</SUP> calendar Yellow-legged Gull in advance of some further comments on your bird. My image was obtained early September 2005 less than a mile from my place of work. It was initially spotted as a juvenile/1<SUP>st</SUP> winter & returned this August for its 6<SUP>th</SUP> year. Although YLG has bred irregularly in the UK since 1995, the origins of this individual are not known. The species remains a scare, but steadily increasing, visitor to NE England.

I do have some flight images taken at the same time, so I will locate these & post any that may help the ID process.

Cheers: Wayne

[Wayne Richardson]

This is a ‘bill to tail’ summary of my take on Marko’s Gull with particular emphasis on ID features of the likely candidates, i.e. Caspian Gull (CG) or Yellow-legged Gull (YLG) &, where necessary, comparison with Lesser Black-backed Gull (LBBG) & European Herring Gull (EHG). In addition, I will also refer to my images as YLG UK, but note this is 2nd summer bird moulting to 3rd winter. Extracts etc from Gulls of Europe, Asia & North America by Olsen & Larsson will be shown as GEANA.

The overall jizz of gull looks like a YLG, i.e. large headed with a powerful bill & is more muscular than the small headed, weak billed & rather slim CG. It must always be stressed that male & female gulls of the same species can look quite different. I believe the YLG UK is a male & Marko's is a female.

It is the colour of the bill which I considered a 2nd calendar year feature, as it is quite yellow on YLG UK, plus the illustrations & images in GEANA. Bill colour is closer to GEANA’s illustration of 3rd winter CG, but even that is dull yellow rather than pale pink.

The eyes are pale & even adult CG often have dark eyes.

The lightly streaked nape is normal for 3rd winter CG, with YLG usually more hooded in appearance. However, the YLG UK shows no streaking at all even by early Sep.

The mantle colour is considered a shade or 2 paler than the palest graellsii LBBG. It is spot on for YLG, but too dark for CG. Far less brown coverts etc visible than on YLG UK, but I consider Marko’s bird is further advanced in its moult, i.e. only primary 10 is not fully developed. The YLG UK has primary 7 still growing, but retains 2nd year primaries 8 to10. I've assumed, perhaps incorrectly, Marko's image was obtained in Oct. GEANA indicates 3rd winter plumage attained with a complete moult & begins earlier than adults. It states even by late Jun some bird had replaced up to primary 6, some coverts & part of tail.

Underwing pattern is a paler version of that shown by LBBG, so again a characteristic that fits YLG, but not CG or EHG.

Legs are definitely pink & this feature is giving me the most concern, as they look very much like you would find on EHG. These should be dull yellow or fleshy at best on YLG & even paler/greyer on CG.

Tail should still have some dark barring although the extent is very variable between individuals of same age.

My personal experience of YLG is that they look like those illustrated in GEANA, so I have not come across any that have legs with no obvious yellowish tinge.

As with any large gull that doesn’t fit the bill, you have to consider hybrids. It appears YLG has paired with both EHG & LBBG in NW Europe & there are unsubstantiated claims of hybrid YLG & CG from Poland. Generally, YLG does not hybridise freely when compared with other species.

So I'm still in the YLG camp, but with a couple of reservations.

Cheers: Wayne