Intermedius vs fuscus (1 Viewer)

With recent reports of fuscus from Cley I was just hoping for someone to give me a refresher course on ID

I photographed this adult bird at Cley today (on right). Sorry only phone photo so not great

It struck me as very dark and very little white in primaries. It can be seen to be as dark as the GBBG next to it

Does the fact that it is in primary moult rule out fuscus straight away ?

PS There were lots of LBBgulls there today - most normal looking but there was one other dark bird ... though not as striking as this bird

:t:Not too sure about that,but as they are another northern European brd I would have thought moult was little different from others ,and if anything would start earlier the further north you go as summers(breeding season)B are shorter

Thanks. From the details I have found online it sounds as though a combination of features and more importantly, a big white plastic ring! Is the clincher