I went to photo the Kumlien’s Gull lunch time and found there was a second bird there that also seems to be a Kumlien’s Gull. This second bird has a distinct pale base to the bill unlike the other which has an all dark bill and appears in recently published photos. Both birds were present for comparison.
Glamorgan Bird Club 
Hi Wayne, help me here what makes this Kumlien’s and not 1cy Iceland gull. Mike
Id of the two Kumliens Gulls is explored on the Glamorgan Rarities Committee blog.
Thanks Wayne I have just had a look at the site and comments on the gulls. Mike