mich?

[lou bertalan]

from the last set of cristian's pics, 9.12.2010 bucharest:

http://www.birdforum.net/showpost.php?p ... count=1602

and a 2cy micha: http://www.birdforum.net/attachment.php ... 1292082281 (note large pale tips to p3 and p4!)

i'd like to have your opinions about this 1cy:

http://www.birdforum.net/attachment.php ... 1292003892

http://www.birdforum.net/attachment.php ... 1292013853

it has a rel. pale underwing, a hint of a pale base to p10, hint of a collar and large pale inner webs to primaries - all caspian traits. bill can fit both sp. i think, there are caspians with such bulbous tips but usually it fits better a mich. base of bill gets slightly paler, nothing too uncommon in michahellis but again better for cach. tail band doesn't seem to taper in the corners but again there seem to be no thin additional subterminal bands like in most/many cachs.

i'm swaying between mich and cach because on first impression it seemed to be a michahellis but many things point to cach... for me a not so straightfort bird. so what's your impression?

cheers,

lou

[adriaens]

I lean more towards Caspian Gull, Lou.
In addition to the features you have already mentioned, the pattern of the greater coverts fits Caspian better, and on the head I would expect to see more of a dark 'mask' around the eye.
Also, I know it is subjective, but I think jizz of this bird is spot-on for Caspian Gull: long wings, long neck, and long flat forehead creating a 'snout'. I sometimes think that, due to their long-necked appearance, Caspian Gulls may give a rather goose-like impression in flight.

[lou bertalan]

I lean more towards Caspian Gull, Lou.
In addition to the features you have already mentioned, the pattern of the greater coverts fits Caspian better, and on the head I would expect to see more of a dark 'mask' around the eye.
Also, I know it is subjective, but I think jizz of this bird is spot-on for Caspian Gull: long wings, long neck, and long flat forehead creating a 'snout'. I sometimes think that, due to their long-necked appearance, Caspian Gulls may give a rather goose-like impression in flight.

thanks peter. i got to say that i have difficulties in judging jizz in pics of flying gulls if not very obvious. cach and mich are pretty close regarding wing proportions (unlike herring gull) but the flat belly with 2 bumps in caspian often is of help. not so in this case where i don't really see the goose like appearance versus shorter necked michahellis.
inner primaries with larger pale portions in caspian is an unreliable thing too imo since it varies a lot in both sp., well tendentially caspians have a clearer 'window'. GC pattern - well if there were clear pale tips to them...but a plain pattern is found in both sp.
bill length actually drew me more towards caspian and that the base is not as high as in most michs. one more pontic with "blown up" bill tip?
now, after looking at many details including tail, upper scaps, 2nd gen. coverts and underwing MC pattern i got more or less satisfied with the ID as cachinnans

merci

lou

[JanJ]

It just goes to show how complicated some of this species pair is to identify, both from certain pic. and in real life. We see only two views in two angles -where upperparts isn´t viewed. However, from the two pic I´m in the Caspian camp if any, and for the reasoms mentioned. I know that Caspian (males) can show unexpectedly large bills with an obvious pronaunced gonys angle, so that leaves no imediate problematics as to the identity regarding this gull, I can however, understand if it does for some others.
Peter mention the greater coverts as being a better fit for Caspian, however, imo they are likely to be more typical of YLG, being uniformly coloured throughout their whole lenght - like this individual:
http://www.helsinki.fi/~rauste/juvmic/y ... 67346.html

as opposed to the more typical of Caspian:
http://www.pbase.com/slisch/image/128276503

Pattern of greater coverts is, as you all know, quite variable in both these sp.
The pale axillaries and undewing parts visible - are further more good indications for Caspian - although there are the eventual YLG with a similar pattern I think it is a better case for Caspian.

The more wellmarked YLG:
http://www.birdforum.net/attachment.php ... 1292003857

How I would like to see n upperparts viewing of thei gull. What do you say Cristian?

Jan

[michal rycak]

Hi gents!
In subject of large billed Caspian males please take a look at these two pictures:

http://forum.przyroda.org/download.htm?id=53622

http://forum.przyroda.org/download.htm?id=53621

both birds are from breeding colony in SE Poland.

[Cristian Mihai]

Sorry Jan, I don't have more pics with this bird...