Tony

I think first one is Yellow-legged Gull but the second one does not appear as Black-tailed Gull to me.
The bill is quite short in the photo and the colour of the 1st winter Black-tailed looks browner than this one.
http://orientalbirdimages.org/se ... _ID=&pagesize=1
Would it be a Mew Gull instead?
http://www.hkbws.org.hk/BBS/viewthread.php?tid=10979

Will wait for expert for confirmation.