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[Switzerland] Yellow-legged Gull vs Lesser Black-backed Gull (1 Viewer)
- Thread starter rafnuss
- Start date
CARERY
Well-known member
I'm answering mainly to put this threat up for Lou to find it. I'm never completely confident when it comes to ID immature gulls but IMO this can't be a LBBG just because the bill is too strong. The inner primaries seem all dark but I think it's OK for YLG - a rather dark one though?
SteveClifton
Well-known member
Agree with the above. Also the greater covert bar isn't so well-developed as most darker 1cy LBBGs and the extensively replaced median and lesser coverts surely favour YLG over LBBG.
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Thank you both for you help,
Just to make sure I understand, can you confirm, developed means replaced by new or old feather?
Is my drawing correct?
To be honest, I really don't see the difference with such a bird: http://www.gull-research.org/lbbg1cy/1cyoct021.html
How are they more or less developed?
Thanks again for helping me!
Just to make sure I understand, can you confirm, developed means replaced by new or old feather?
Is my drawing correct?
To be honest, I really don't see the difference with such a bird: http://www.gull-research.org/lbbg1cy/1cyoct021.html
How are they more or less developed?
Thanks again for helping me!
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lou salomon
the birdonist
hi,
roland and steve are right, this is a 1cy YLG, the well marked head has been achieved during postjuvenile moult, now being much darker than by the end of august, beginning of september. the strong bill, venetian blind pattern (dark-pale inner hand) with paler inner webs than in LBBG, but especially the large amount of replaced (moulted, 2nd gen.) lesser coverts makes it a YLG. the inner GC you have marked as "developed" are still juvenile btw., they just are more patterned than the outers.
cheers
roland and steve are right, this is a 1cy YLG, the well marked head has been achieved during postjuvenile moult, now being much darker than by the end of august, beginning of september. the strong bill, venetian blind pattern (dark-pale inner hand) with paler inner webs than in LBBG, but especially the large amount of replaced (moulted, 2nd gen.) lesser coverts makes it a YLG. the inner GC you have marked as "developed" are still juvenile btw., they just are more patterned than the outers.
cheers
SteveClifton
Well-known member
Hope this helps
Re the greater covert-bar: by 'developed' I meant well-marked though IMO the intensity can change with viewing angle. It's often (on average) more obvious on LBBGs but you are correct in that many YLG have very similarly marked 'bar' there so perhaps a less useful feature than moult stage, hence please ignore my reference to it :smoke:
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