Herring Gull, Warsaw, Poland, 19 Feb (1 Viewer)

[01101001]

I've appraised the primary pattern based on the chart for adult (this bird appears to have some slight brownish hue at the end of the tongues on the outer primaries, though) gulls from https://www.researchgate.net/public...lity_and_the_field_characteristics_of_hybrids and, to my eye, it maxes out the score for primary structure (at least 13 out of 20), so I know it's not a Caspian Gull (4-12), but how can I tick a Herring Gull in Central Europe (even if I had good views on the eye, bill and legs of this gull) given the complete overlap between pure Herring Gulls (12-20) and Caspian Gull x Herring Gull hybrids (9-20)?

EDIT: The two remaining photos may be of this bird or another similar one close to it.

 

[01101001]

Perhaps a combination of a yellow eyering and no black on P5 would make the cut (from the table on page 12)?

I'm not saying the above is fine for a pure Herring Gull (or that the photo is good enough to judge), only asking a more general ID question.

 

[lou salomon]

it's a Common Gull.

 

[01101001]

Thanks a lot; part of my question still stands, though--is it possible to safely ID a pure Herring Gull?

 

[lou salomon]

you can ID pure Herring Gulls even in Central Europe. Overlap of all features doesn't mean that a combination of many typical treats summed up together don't reveal the identity of a more or less typical argentatus: pale irides, lack of a solid p5 mark, diagonal shaped white ventral p10 tongue together with large mirrors plus stocky structure, shortish legs, "triangular" head, short and strong legs, short primary projection.

 

[01101001]

16 April, same location

traits scored as per the paper are in the attachment

possible hurdles (from the post above): the P10 to tongue on the underside seems greyish, not white; hard to assess the pp--maybe a hybrid, then?

 

[Alexander Stöhr]

Hello,
like you I hope for Lou and others to jump in.
And when your bird had a clear pale iris , nearly without any dark marks (cant judge this on the pictures and my screen), than I think of an Herring x Caspian Gull hybrid, too.

Please note, that your bird has a narrow, but complete black band on p5, at least on the right wing (but this is also present in some Herring Gulls).

But better wait for others. Thanks from me too!

 

[lou salomon]

looks like a normal Herring Gull. just with a long p10 tongue, but that's not unusual in nominate argentatus.

 

[01101001]

a black band on P5 would significantly lower the score?

 

[lou salomon]

not really. there are plenty of HG with complete black subterminal marks to p5 out there.

 

[01101001]

Here's an argentatus Herring Gull that I found in the Collins Guide (pardon the language), having no black subterminal band on P10. Also, both individuals shown here have a thicker or thinner conplete black band on P5.

I think I'm slowly getting the hang of it--yesterday, I observed a good candidate for a Caspian Gull through bins: longish bill, elongated body, much white in wingtips, outer upperwing much paler than mantle.

 

[01101001]

I'm afraid I can't see a diagonal ventral tongue in my pictures from April: rather, it looks like the ventral tongue occupies only the inner web of P10. On the other hand, there is a diagonal dorsal tongue, but I don't think it counts?

 

[lou salomon]

it's a rectangular tongue end and yes, ventral tongues are always on the inner web only. dorsal tongues count, they are indicative of cachinnans if seen well (wing tip must be spread).

 

[01101001]

dorsal tongues count, they are indicative of cachinnans if seen well (wing tip must be spread).

whitish (rectangular?) dorsal P10 tongue in the case of cachinnans?

 

[lou salomon]

Usually yes. this must be seen in the context of other traits, though since a few HG and YLG also have a rectangular tongue. your bird from 16 april has a very pale iris and an apparently stubby bill (if it's the same as in the last two pics from yesterday), that's why I opted for HG, but the primary pattern is more of a Caspian Gull, so, being in Warsaw it could well be a hybrid cachinnans x argentatus. To identify a hybrid with certainty you'd need accurate pics of the spread wing, though. Hybrids tend to have shorter and grey instead of white dorsal tongues, and shorter ventral tongues.

 

[01101001]

Thanks a lot