This is the only video footage I managed to get without any background conversation.Well it is pretty much now confirmed that this is no longer a probable but "an as good as it can get" definate Slaty Backed Gull. What a find ! "Inner Thames"& London it is almost getting to the stage where the Thames complex from Pitsea-Rainham-Beddington is getting first class Vagrant Gulls and is becoming more of a reliability than the west coast of Ireland. For more better quality images go to:
Also Adrian Webb got some good shots proving good flight views on surfbirds:
And lastly well done to Dominic Mitchell for this high class find!!