2cy mich or arg?

[ENG]

Hello all!

This is my first entry to this forum, and maybe I reveal myself as a very little competent "guller" by posting this entry, but so be it...
2cy gulls are among the most difficult I can imagine, since the variation is seemingly unfathomable...The last 6 years, I have scratched my head bloody, trying to get to grips with this age-group (as if 1cy birds are easy...). Often, when I've had suspicions about 2cy mich's, they've turned out to be 3cy arg's when the inner primaries have become visible.

Yesterday, I found this gull in Fredrikstad, southeastern Norway that I really struggle to identify. It shows features that I do not normally see in 2cy's in our local argentatus (more often in 3cy's actually). It is really contrasting and advanced compared to the average arg with predominantly medium grey mantle/scapulars, a scattering of pure grey greater, median and lesser coverts, new 4th(?) generation upper tertials, almost pure white head/under-body, predominantly white underwing, a contrasting black tapering tailband and mostly dark bill. In addition to these plumage-characters, it shows a nice compact (athletic) build with protruding breast. Until now, I guess I have made a description of a typical 2cy michahellis, and I would have claimed the bird as such if it hadn't been for the head/bill - shape. I like my YLGulls to be text book cases, since the species is rare in Norway (about 20 records in Norway, about 10 from Fredrikstad). I therefore have chosen to ask you experts for help on this one. I don't need to be told that "the variation is enormous" etc, since I know that allready...I like to "close" my cases (don't like "hung" cases), so I would appreciate any help to identify this bird - if possible - from the photographs.

What I would like you to note in the photographs are:
- Moult stage: new grey coverts among greater, median and lesser coverts. Note that the sole picture of the left side shows more new grey coverts than on the right side. New upper tertials of 4th gen type?
- Tail band, compatible with arg?
- White under wing
- Structure compared to herring gulls - it sure looks athletic and mich-like to me...
- haed and bill - is it possible for a YLG to look like this?

Also note that the bird had been wading in dirt, so the leg colour is very misleading. Above the heel, you can discern the true leg colour. In the field it looked colourless/pale.

Thanks in advance!

-Stein-

[ENG]

Forgot the picture from the left hand side showing more advanced moult in the (especially) median coverts. Well, here it is..

[Theo Muusse]

I understand that you hesitate.
It does look like a small female 2cy (inner wing) michahellis, judging all the pictures.
I must say that I am far from sure, since details are just be bit too hard to see.
The inner primaries give an argentatus feeling..

Theo Muusse

[JanJ]

Although I understand Stein arguing against argentatus from an plumage/age and time point of view, I´m preapared to almost accept his gull as a 2cy michahellis. In some pic. structure seems alright - with high breast and slender look. Headshape might confuse but that´s not a major problem, which would be common knowledge for the people involved.
The coverts, excluding greater, seems to lack any large dark-centered feathers - more untidy Herring like.
Some more suggestions would be nice.

Jan

[lou bertalan]

hi,

definitely not an easy bird. tertials look strange for micha. also, i'm used to see some grey MC by this time in michas but this isn't a real problem of course.
colour shape of head and bill aren't conclusive, though generally speaking such a pale head and dark bill are more likely in YLG.
what i don't like are the rel. short wings (esp. female michas usually have longer ones!) and the covert pattern for micha. i'm tending towards an advanced argentatus although i have no extensive experience with this taxon.

best,

[ENG]

Hi all!

Thank you for the replies. I just returned from a week in Spain and it didn't really prepare me for dismissal of this bird as a mich by the grounds stated. Even though the number of closely studied 2cy's were rather moderate (about 50 individuals), I had few problems finding birds with similar tertials, coverts or wing-lenghts. I have no problems, however, putting this gull into the "not-safely-identified" bag. I've checked about 5000 argentatus the last 2 days after similar birds without luck, so it really is a bit special - at least up here...

Best wishes

Stein