Yellow Legged Gull, Switzerland (1 Viewer)

Hello,
I found this first year (If I'm not wrong) gull and was just wandering how to differentiate a potential Lesser Black-backed Gull. The size seem quite smaller and the greater cover very black. What should I be looking at ?
thanks,

Here is a link to better photo: https://goo.gl/photos/uMsk5UT7mHeHbPDe9

Doesn't seem different from a LBBG to me though I'm no expert.

they are very similar. still, this looks to be a small female michahellis of the plain type (no strong pattern in greater coverts). leg length is a small hint, paler head than fuscus types (and not as uniform dark, but two toned). in flight you should note the narrower and contrasting tail band and paler inner primaries (pale inner webs).

Hi,
Thank for your replies.
I am a bit confuse, look at this LBBG: http://www.gull-research.org/lbbgaugsep/1cyaug02.html

Very white head, long leg, some diffuse gradient in the Greater cover. What make it LBBG then ?

you can go on and pick out 1000s of pics, wondering why it is this and not the other. it needs some experience. in this case: small head, very long wings with hardly any pale crescents at tips of primaries, inner greater covert pattern not as regular as in the average michahellis. but variation is huge! best is to see tail and inner wing in these two, when juvenile. by the end of august (22.08. of your linked LBBG) there is another important difference: YLG usually is much more worn, i.e. fringes of coverts get abraded. and scapular moult is more advanced in the early breeding southern taxon michahellis while LBBG usually still looks fresh well into early autumn, with just few scaps replaced. in september/end of august some michahellis already have replaced even some inner lesser and median coverts, while LBBG replaces just scapulars and in a slower pace. usually

cheers

Thank you Lou,
You're right, I need more experience. I've my whole life to gain it. Hopefully, I'll improve. If you have any advice on how to gain it, it would be very well welcome!