I think it may be but not 100% certain. Looking at my RSPB Handbook it could be a 1st Winter bird.
David I'm afraid I can't help you with this - you may be lucky and it will be spotted by one of the renowned national experts that occasionally visit our forum or alternatively post it straight to the 'Identify This' forum where you will be answered almost immediately in my experience (see my next post)
Sorry, Birdie Wild I should have closed this as I did what John suggested and put it on the "identify This" forum. It has not been definitely identified but the the experts believe it is "more likely to be a small first year Herring Gull.