Gull ID - Belfast, Ireland (1 Viewer)

[martyrynin]

Hey,

I saw this gull this evening.

It stood out to me because of the blue-grey saddle.

I thought initially it was just a sub-adult Lesser black-backed gull which explained the lighter saddle colour.
Now I'm not sure. I've included photos of it beside both Argenteus and Graellsii for comparison.

Around May last year a Yellow legged gull was spotted in this area, so it seems possible.
It does appear to be a sub-adult gull either way.

 

[Alexander Stöhr]

Hello Leif,

interesting bird, tfs!

First gut feeling is a 4cy Lesser Black backed Gull by steep rounded forehead and quite slender bill, resulting in a strong built (male-type???) LBBG jizz.

And I thought subadult Yellow legged Gulls should have a large white mirror on p10.
But gull-research told me otherwise Gull Research Organisation

Please compare to this Yellow-legged Gull (Rheinauer See, SW-Germany, 25.12.2017)

https://flic.kr/p/EZhQna

https://flic.kr/p/24Donb4

But I am unsure and hope for more comments. Lou and all, please!

edit: your Gulls seems to lack any darker area on the inner primaries and visible secondaries. Yes, its sonetimes not that obvious on LBBGs, but here they seems so pale, better for a YLG?

 

[martyrynin]

Hello Leif,

interesting bird, tfs!

First gut feeling is a 4cy Lesser Black backed Gull by steep rounded forehead and quite slender bill, resulting in a strong built (male-type???) LBBG jizz.

And I thought subadult Yellow legged Gulls should have a large white mirror on p10.
But gull-research told me otherwise Gull Research Organisation

Please compare to this Yellow-legged Gull (Rheinauer See, SW-Germany, 25.12.2017)

https://flic.kr/p/EZhQna

https://flic.kr/p/24Donb4

But I am unsure and hope for more comments. Lou and all, please!

edit: your Gulls seems to lack any darker area on the inner primaries and visible secondaries. Yes, its sonetimes not that obvious on LBBGs, but here they seems so pale, better for a YLG?

Thank you for your response Alexander!

I'm finding this one really tricky, but am slightly leaning towards Yellow-legged. Happy to be corrected of course.

So the primaries unfortunately seem to be very similar between YLG and LBB, although one thing I have noticed is that the black on p10 - p8 of an LBB have quite a similar amount of black before dropping down at p7.
E.g. Lesser Black-backed Gull - graellsii & intermedius

YLG on the otherhand has more of a gradient of reducing black from p10 - p8.

Also when I use a colour picker on the saddle, blue is the most significant colour in the RGB scale, so the apparent blue tone is there.
In the other Graellsii the red component is largest (slightly brownish in the evening light).

Could you explain a bit about what you mean by "visible secondaries" please?

Edit: Another point too is the amount of white on the primary tips (moons) seems like a lot for LBB, particularly sub-adult.

 

[Alexander Stöhr]

Hello Leif,

sorry I wasnt clear: I meant the underside of the wing. Normally adult and subadult LBBG have darker secondaries (and inner primaries) on the underwing, sometimes forming a darker rear band.
This could well be visible, if present, in your 5. picture.

Looking at this picture again, I am not so sure: you are right, the relevant area seems pale smokygrey and not contrasting. Taking light and angle into account, this could fit both LBBG and YLG.

 

[martyrynin]

Hello Leif,

sorry I wasnt clear: I meant the underside of the wing. Normally adult and subadult LBBG have darker secondaries (and inner primaries) on the underwing, sometimes forming a darker rear band.
This could well be visible, if present, in your 5. picture.

Looking at this picture again, I am not so sure: you are right, the relevant area seems pale smokygrey and not contrasting. Taking light and angle into account, this could fit both LBBG and YLG.

Thank you so much Alexander. The underwing was key to solving this one.

It is a Yellow-legged gull

See attached some clearer photos of the underwing, which has some modest grey, but I've included the underwing of a LBB to show how striking the difference is.

Also the head looks fat, and not pear shaped like the other LBB.