www.gull-research.org

these pics where published on birdforum by dimtris (who photogr. the bird) tonight. slightly embarassing, i initially thought it was a really sensational 1cy YLG with almost replaced primaries! it's a late moulter - p10 are still juvenile, taken last week in athens. can we conclude it is a 2cy northern or northeastern male herring gull? structurally this bird on first view looked absolute in line with michehellis.

http://www.birdforum.net/attachment.php ... 1262468276

http://www.birdforum.net/attachment.php ... 1262468301

http://www.birdforum.net/attachment.php ... 1262468325

lou

It still does look good for a ylg or gbbg.
The highly contrasting coverts look bad for a Herring.
The moult suggest a very advanced first winter or very slow 2nd winter.
I would not be surprised if this is a 2nd winter, gbbg can be very late.
The p10 looks pretty worn for a first winter, except when its a ill bird.
Any flight pics? Or more details on the tail?

Theo

did you encounter such birds already? p10 are the only juvenile feathers i can see! renewed primaries in postjuvenile moult? i didn't know that. surely pattern on 2nd gen. feathers and structure says YLG but i thought it "impossible". renewed all coverts, tertials and rectrices i knew, but also primaries??

Just goes to show how simlar some michahellis and some marinus can be. As Theo mentioned, argentatus/argenteus is not a good candidate.
However, a 1cy michahellis with such an advanced moult in Dec. is quite possible. There´s just one problem for such a bird at this time of year, or any 1cy LWHG at this latitude - the active primary moult.

What would you call the darker gull in the middle in pic 8 (also in pic. 9) here:

http://www.mallorcaweb.net/gavines/atipiques.htm

Jan

obviously the primary moult isn't impossible. to me the athens bird doesn't look like a gbbg. head and bill, large eyes, more elegant body - i don't see a female marinus nor do i in the dark bird #8 and #9 at "plomatges atipics". dimitris posted another bird today which is similarly developed (but no new primaries) showing active moult in rectrices, 2nd pic:

http://www.birdforum.net/attachment.php ... 1262541815
http://www.birdforum.net/attachment.php ... 1262541827
http://www.birdforum.net/attachment.php ... 1262541840

maybe this bird also has some resemblance with them:

http://www.birdforum.net/showpost.php?p ... tcount=659
http://www.birdforum.net/showpost.php?p ... tcount=660 (the pale bird i think is another YLG, not pontic as initially thought).

all this thread would have been good to be included in this forum: viewforum.php?f=5
not in the herring gull section i have put it by my personal mistake.